sewardj | de4a1d0 | 2002-03-22 01:27:54 +0000 | [diff] [blame] | 1 | |
| 2 | /*--------------------------------------------------------------------*/ |
| 3 | /*--- Implementation of POSIX signals. ---*/ |
| 4 | /*--- vg_signals.c ---*/ |
| 5 | /*--------------------------------------------------------------------*/ |
| 6 | |
| 7 | /* |
njn | c953984 | 2002-10-02 13:26:35 +0000 | [diff] [blame] | 8 | This file is part of Valgrind, an extensible x86 protected-mode |
| 9 | emulator for monitoring program execution on x86-Unixes. |
sewardj | de4a1d0 | 2002-03-22 01:27:54 +0000 | [diff] [blame] | 10 | |
njn | 0e1b514 | 2003-04-15 14:58:06 +0000 | [diff] [blame] | 11 | Copyright (C) 2000-2003 Julian Seward |
sewardj | de4a1d0 | 2002-03-22 01:27:54 +0000 | [diff] [blame] | 12 | jseward@acm.org |
sewardj | de4a1d0 | 2002-03-22 01:27:54 +0000 | [diff] [blame] | 13 | |
| 14 | This program is free software; you can redistribute it and/or |
| 15 | modify it under the terms of the GNU General Public License as |
| 16 | published by the Free Software Foundation; either version 2 of the |
| 17 | License, or (at your option) any later version. |
| 18 | |
| 19 | This program is distributed in the hope that it will be useful, but |
| 20 | WITHOUT ANY WARRANTY; without even the implied warranty of |
| 21 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 22 | General Public License for more details. |
| 23 | |
| 24 | You should have received a copy of the GNU General Public License |
| 25 | along with this program; if not, write to the Free Software |
| 26 | Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA |
| 27 | 02111-1307, USA. |
| 28 | |
njn25 | e49d8e7 | 2002-09-23 09:36:25 +0000 | [diff] [blame] | 29 | The GNU General Public License is contained in the file COPYING. |
sewardj | de4a1d0 | 2002-03-22 01:27:54 +0000 | [diff] [blame] | 30 | */ |
| 31 | |
jsgf | 855d93d | 2003-10-13 22:26:55 +0000 | [diff] [blame] | 32 | /* |
| 33 | New signal handling. |
| 34 | |
| 35 | Now that all threads have a ProxyLWP to deal with signals for them, |
| 36 | we can use the kernel to do a lot more work for us. The kernel |
| 37 | will deal with blocking signals, pending blocked signals, queues |
| 38 | and thread selection. We just need to deal with setting a signal |
| 39 | handler and signal delivery. |
| 40 | |
| 41 | In order to match the proper kernel signal semantics, the proxy LWP |
| 42 | which recieves a signal goes through an exchange of messages with |
| 43 | the scheduler LWP. When the proxy first gets a signal, it |
| 44 | immediately blocks all signals and sends a message back to the |
| 45 | scheduler LWP. It then enters a SigACK state, in which requests to |
| 46 | run system calls are ignored, and all signals remain blocked. When |
| 47 | the scheduler gets the signal message, it sets up the thread to |
| 48 | enter its signal handler, and sends a SigACK message back to the |
| 49 | proxy, which includes the signal mask to be applied while running |
| 50 | the handler. On recieving SigACK, the proxy sets the new signal |
| 51 | mask and reverts to its normal mode of operation. (All this is |
| 52 | implemented in vg_syscalls.c) |
| 53 | |
| 54 | This protocol allows the application thread to take delivery of the |
| 55 | signal at some arbitary time after the signal was sent to the |
| 56 | process, while still getting proper signal delivery semantics (most |
| 57 | notably, getting the signal block sets right while running the |
| 58 | signal handler, and not allowing recursion where there wouldn't |
| 59 | have been normally). |
| 60 | |
| 61 | Important point: the main LWP *always* has all signals blocked |
| 62 | except for SIGSEGV, SIGBUS, SIGFPE and SIGILL (ie, signals which |
| 63 | are synchronously changed . If the kernel supports thread groups |
| 64 | with shared signal state (Linux 2.5+, RedHat's 2.4), then these are |
| 65 | the only signals it needs to handle. |
| 66 | |
| 67 | If we get a synchronous signal, the details are placed into |
| 68 | VG_(unresumable_siginfo) and we longjmp back into the scheduler, |
| 69 | since we can't resume executing the client code. The scheduler |
| 70 | immediately starts signal delivery to the thread which generated |
| 71 | the signal. |
| 72 | |
| 73 | On older kernels without thread-groups, we need to poll the pending |
| 74 | signal with sigtimedwait() and farm any signals off to the |
| 75 | appropriate proxy LWP. |
| 76 | */ |
sewardj | de4a1d0 | 2002-03-22 01:27:54 +0000 | [diff] [blame] | 77 | |
| 78 | #include "vg_include.h" |
jsgf | 855d93d | 2003-10-13 22:26:55 +0000 | [diff] [blame] | 79 | #include <stddef.h> /* OK, no library dependencies */ |
sewardj | de4a1d0 | 2002-03-22 01:27:54 +0000 | [diff] [blame] | 80 | |
sewardj | 018f762 | 2002-05-15 21:13:39 +0000 | [diff] [blame] | 81 | /* Define to give more sanity checking for signals. */ |
| 82 | #define DEBUG_SIGNALS |
| 83 | |
| 84 | |
jsgf | 855d93d | 2003-10-13 22:26:55 +0000 | [diff] [blame] | 85 | /* |
sewardj | fa35651 | 2002-05-24 00:00:59 +0000 | [diff] [blame] | 86 | - The following causes an infinite loop: start Hugs, Feb 2001 |
| 87 | version, and do Control-C at the prompt. There is an infinite |
| 88 | series of sigints delivered (to the client); but also seemingly |
| 89 | to valgrind, which is very strange. I don't know why. |
| 90 | |
jsgf | 855d93d | 2003-10-13 22:26:55 +0000 | [diff] [blame] | 91 | [I haven't re-tested this, but this is likely fixed - JSGF] |
sewardj | fa35651 | 2002-05-24 00:00:59 +0000 | [diff] [blame] | 92 | */ |
| 93 | |
| 94 | |
sewardj | 018f762 | 2002-05-15 21:13:39 +0000 | [diff] [blame] | 95 | /* --------------------------------------------------------------------- |
| 96 | Forwards decls. |
| 97 | ------------------------------------------------------------------ */ |
| 98 | |
jsgf | 855d93d | 2003-10-13 22:26:55 +0000 | [diff] [blame] | 99 | static void vg_sync_signalhandler ( Int sigNo, vki_ksiginfo_t *info, struct vki_ucontext * ); |
| 100 | static void vg_async_signalhandler ( Int sigNo, vki_ksiginfo_t *info, struct vki_ucontext * ); |
| 101 | static void vg_babyeater ( Int sigNo, vki_ksiginfo_t *info, struct vki_ucontext * ); |
| 102 | static void proxy_sigvg_handler ( Int sigNo, vki_ksiginfo_t *info, struct vki_ucontext * ); |
sewardj | 018f762 | 2002-05-15 21:13:39 +0000 | [diff] [blame] | 103 | |
jsgf | 855d93d | 2003-10-13 22:26:55 +0000 | [diff] [blame] | 104 | static Bool is_correct_sigmask(void); |
| 105 | static const Char *signame(Int sigNo); |
sewardj | 018f762 | 2002-05-15 21:13:39 +0000 | [diff] [blame] | 106 | |
| 107 | /* --------------------------------------------------------------------- |
| 108 | HIGH LEVEL STUFF TO DO WITH SIGNALS: POLICY (MOSTLY) |
| 109 | ------------------------------------------------------------------ */ |
| 110 | |
jsgf | 855d93d | 2003-10-13 22:26:55 +0000 | [diff] [blame] | 111 | /* If set to true, the currently running kernel doesn't do the right |
| 112 | thing with signals and LWPs, so we need to do our own. */ |
| 113 | Bool VG_(do_signal_routing) = False; |
| 114 | |
fitzhardinge | e1c06d8 | 2003-10-30 07:21:44 +0000 | [diff] [blame] | 115 | /* Set of signal which are pending for the whole process. This is |
| 116 | only used when we're doing signal routing, and this is a place to |
| 117 | remember pending signals which we can't keep actually pending for |
| 118 | some reason. */ |
| 119 | static vki_ksigset_t proc_pending; /* process-wide pending signals */ |
| 120 | |
jsgf | 855d93d | 2003-10-13 22:26:55 +0000 | [diff] [blame] | 121 | /* Since we use a couple of RT signals, we need to handle allocating |
| 122 | the rest for application use. */ |
| 123 | Int VG_(sig_rtmin) = VKI_SIGRTUSERMIN; |
| 124 | Int VG_(sig_rtmax) = VKI_SIGRTMAX; |
| 125 | |
| 126 | Int VG_(sig_alloc_rtsig)(Int high) |
| 127 | { |
| 128 | Int ret; |
| 129 | |
| 130 | if (VG_(sig_rtmin) >= VG_(sig_rtmax)) |
| 131 | ret = -1; |
| 132 | else |
| 133 | ret = high ? VG_(sig_rtmin)++ : VG_(sig_rtmax)--; |
| 134 | |
| 135 | vg_assert(ret >= VKI_SIGRTUSERMIN); |
| 136 | |
| 137 | return ret; |
| 138 | } |
| 139 | |
sewardj | de4a1d0 | 2002-03-22 01:27:54 +0000 | [diff] [blame] | 140 | /* --------------------------------------------------------------------- |
sewardj | de4a1d0 | 2002-03-22 01:27:54 +0000 | [diff] [blame] | 141 | Signal state for this process. |
| 142 | ------------------------------------------------------------------ */ |
| 143 | |
sewardj | 018f762 | 2002-05-15 21:13:39 +0000 | [diff] [blame] | 144 | |
sewardj | b48e500 | 2002-05-13 00:16:03 +0000 | [diff] [blame] | 145 | /* Base-ment of these arrays[VKI_KNSIG]. |
| 146 | |
| 147 | Valid signal numbers are 1 .. VKI_KNSIG inclusive. |
| 148 | Rather than subtracting 1 for indexing these arrays, which |
| 149 | is tedious and error-prone, they are simply dimensioned 1 larger, |
| 150 | and entry [0] is not used. |
| 151 | */ |
| 152 | |
sewardj | b48e500 | 2002-05-13 00:16:03 +0000 | [diff] [blame] | 153 | |
sewardj | 018f762 | 2002-05-15 21:13:39 +0000 | [diff] [blame] | 154 | /* ----------------------------------------------------- |
| 155 | Static client signal state (SCSS). This is the state |
| 156 | that the client thinks it has the kernel in. |
| 157 | SCSS records verbatim the client's settings. These |
| 158 | are mashed around only when SKSS is calculated from it. |
| 159 | -------------------------------------------------- */ |
sewardj | b48e500 | 2002-05-13 00:16:03 +0000 | [diff] [blame] | 160 | |
sewardj | 018f762 | 2002-05-15 21:13:39 +0000 | [diff] [blame] | 161 | typedef |
| 162 | struct { |
| 163 | void* scss_handler; /* VKI_SIG_DFL or VKI_SIG_IGN or ptr to |
| 164 | client's handler */ |
| 165 | UInt scss_flags; |
| 166 | vki_ksigset_t scss_mask; |
| 167 | void* scss_restorer; /* god knows; we ignore it. */ |
| 168 | } |
| 169 | SCSS_Per_Signal; |
sewardj | b48e500 | 2002-05-13 00:16:03 +0000 | [diff] [blame] | 170 | |
sewardj | 018f762 | 2002-05-15 21:13:39 +0000 | [diff] [blame] | 171 | typedef |
| 172 | struct { |
sewardj | 2342c97 | 2002-05-22 23:34:20 +0000 | [diff] [blame] | 173 | /* per-signal info */ |
sewardj | 018f762 | 2002-05-15 21:13:39 +0000 | [diff] [blame] | 174 | SCSS_Per_Signal scss_per_sig[1+VKI_KNSIG]; |
sewardj | 2342c97 | 2002-05-22 23:34:20 +0000 | [diff] [blame] | 175 | |
| 176 | /* Signal delivery stack, if any. */ |
| 177 | vki_kstack_t altstack; |
| 178 | |
sewardj | 018f762 | 2002-05-15 21:13:39 +0000 | [diff] [blame] | 179 | /* Additional elements to SCSS not stored here: |
| 180 | - for each thread, the thread's blocking mask |
| 181 | - for each thread in WaitSIG, the set of waited-on sigs |
| 182 | */ |
| 183 | } |
| 184 | SCSS; |
sewardj | b48e500 | 2002-05-13 00:16:03 +0000 | [diff] [blame] | 185 | |
sewardj | 018f762 | 2002-05-15 21:13:39 +0000 | [diff] [blame] | 186 | static SCSS vg_scss; |
| 187 | |
| 188 | |
| 189 | /* ----------------------------------------------------- |
| 190 | Static kernel signal state (SKSS). This is the state |
| 191 | that we have the kernel in. It is computed from SCSS. |
| 192 | -------------------------------------------------- */ |
| 193 | |
| 194 | /* Let's do: |
| 195 | sigprocmask assigns to all thread masks |
| 196 | so that at least everything is always consistent |
| 197 | Flags: |
jsgf | 855d93d | 2003-10-13 22:26:55 +0000 | [diff] [blame] | 198 | SA_SIGINFO -- we always set it, and honour it for the client |
sewardj | 018f762 | 2002-05-15 21:13:39 +0000 | [diff] [blame] | 199 | SA_NOCLDSTOP -- passed to kernel |
| 200 | SA_ONESHOT or SA_RESETHAND -- required; abort if not set |
jsgf | 855d93d | 2003-10-13 22:26:55 +0000 | [diff] [blame] | 201 | SA_RESTART -- we observe this but set our handlers to always restart |
| 202 | SA_NOMASK or SA_NODEFER -- we observe this, but our handlers block everything |
sewardj | 018f762 | 2002-05-15 21:13:39 +0000 | [diff] [blame] | 203 | SA_ONSTACK -- currently not supported; abort if set. |
jsgf | 855d93d | 2003-10-13 22:26:55 +0000 | [diff] [blame] | 204 | SA_NOCLDWAIT -- we observe this, but we never set it (doesn't quite |
| 205 | work if client is blocked in a wait4() syscall) |
sewardj | b48e500 | 2002-05-13 00:16:03 +0000 | [diff] [blame] | 206 | */ |
sewardj | de4a1d0 | 2002-03-22 01:27:54 +0000 | [diff] [blame] | 207 | |
sewardj | 77e466c | 2002-04-14 02:29:29 +0000 | [diff] [blame] | 208 | |
sewardj | 018f762 | 2002-05-15 21:13:39 +0000 | [diff] [blame] | 209 | typedef |
| 210 | struct { |
| 211 | void* skss_handler; /* VKI_SIG_DFL or VKI_SIG_IGN |
| 212 | or ptr to our handler */ |
| 213 | UInt skss_flags; |
| 214 | /* There is no skss_mask, since we know that we will always ask |
jsgf | 855d93d | 2003-10-13 22:26:55 +0000 | [diff] [blame] | 215 | for all signals to be blocked in our sighandlers. */ |
sewardj | 018f762 | 2002-05-15 21:13:39 +0000 | [diff] [blame] | 216 | /* Also there is no skss_restorer. */ |
| 217 | } |
| 218 | SKSS_Per_Signal; |
sewardj | de4a1d0 | 2002-03-22 01:27:54 +0000 | [diff] [blame] | 219 | |
sewardj | 018f762 | 2002-05-15 21:13:39 +0000 | [diff] [blame] | 220 | typedef |
| 221 | struct { |
| 222 | SKSS_Per_Signal skss_per_sig[1+VKI_KNSIG]; |
sewardj | 018f762 | 2002-05-15 21:13:39 +0000 | [diff] [blame] | 223 | } |
| 224 | SKSS; |
| 225 | |
| 226 | static SKSS vg_skss; |
sewardj | de4a1d0 | 2002-03-22 01:27:54 +0000 | [diff] [blame] | 227 | |
jsgf | 855d93d | 2003-10-13 22:26:55 +0000 | [diff] [blame] | 228 | Bool VG_(is_sig_ign)(Int sigNo) |
| 229 | { |
| 230 | vg_assert(sigNo >= 1 && sigNo <= VKI_KNSIG); |
sewardj | 2e93c50 | 2002-04-12 11:12:52 +0000 | [diff] [blame] | 231 | |
jsgf | 855d93d | 2003-10-13 22:26:55 +0000 | [diff] [blame] | 232 | return vg_scss.scss_per_sig[sigNo].scss_handler == VKI_SIG_IGN; |
| 233 | } |
sewardj | b48e500 | 2002-05-13 00:16:03 +0000 | [diff] [blame] | 234 | |
sewardj | 018f762 | 2002-05-15 21:13:39 +0000 | [diff] [blame] | 235 | /* --------------------------------------------------------------------- |
| 236 | Compute the SKSS required by the current SCSS. |
| 237 | ------------------------------------------------------------------ */ |
| 238 | |
sewardj | 4f29ddf | 2002-05-03 22:29:04 +0000 | [diff] [blame] | 239 | static |
sewardj | 018f762 | 2002-05-15 21:13:39 +0000 | [diff] [blame] | 240 | void pp_SKSS ( void ) |
| 241 | { |
| 242 | Int sig; |
| 243 | VG_(printf)("\n\nSKSS:\n"); |
| 244 | for (sig = 1; sig <= VKI_KNSIG; sig++) { |
| 245 | VG_(printf)("sig %d: handler 0x%x, flags 0x%x\n", sig, |
| 246 | vg_skss.skss_per_sig[sig].skss_handler, |
| 247 | vg_skss.skss_per_sig[sig].skss_flags ); |
sewardj | 77e466c | 2002-04-14 02:29:29 +0000 | [diff] [blame] | 248 | |
sewardj | 018f762 | 2002-05-15 21:13:39 +0000 | [diff] [blame] | 249 | } |
sewardj | 018f762 | 2002-05-15 21:13:39 +0000 | [diff] [blame] | 250 | } |
| 251 | |
sewardj | 018f762 | 2002-05-15 21:13:39 +0000 | [diff] [blame] | 252 | /* This is the core, clever bit. Computation is as follows: |
| 253 | |
| 254 | For each signal |
| 255 | handler = if client has a handler, then our handler |
jsgf | 855d93d | 2003-10-13 22:26:55 +0000 | [diff] [blame] | 256 | else if client is DFL, then our handler as well |
| 257 | else (client must be IGN) |
| 258 | if (signal == SIGCHLD), then handler is vg_babyeater |
| 259 | else IGN |
sewardj | 018f762 | 2002-05-15 21:13:39 +0000 | [diff] [blame] | 260 | |
jsgf | 855d93d | 2003-10-13 22:26:55 +0000 | [diff] [blame] | 261 | We don't really bother with blocking signals here, because the we |
| 262 | rely on the proxyLWP having set it as part of its kernel state. |
sewardj | 018f762 | 2002-05-15 21:13:39 +0000 | [diff] [blame] | 263 | */ |
| 264 | static |
| 265 | void calculate_SKSS_from_SCSS ( SKSS* dst ) |
| 266 | { |
| 267 | Int sig; |
sewardj | 018f762 | 2002-05-15 21:13:39 +0000 | [diff] [blame] | 268 | UInt scss_flags; |
| 269 | UInt skss_flags; |
| 270 | |
sewardj | 018f762 | 2002-05-15 21:13:39 +0000 | [diff] [blame] | 271 | for (sig = 1; sig <= VKI_KNSIG; sig++) { |
jsgf | 855d93d | 2003-10-13 22:26:55 +0000 | [diff] [blame] | 272 | void *skss_handler; |
| 273 | void *scss_handler; |
| 274 | |
sewardj | 018f762 | 2002-05-15 21:13:39 +0000 | [diff] [blame] | 275 | scss_handler = vg_scss.scss_per_sig[sig].scss_handler; |
| 276 | scss_flags = vg_scss.scss_per_sig[sig].scss_flags; |
| 277 | |
jsgf | 855d93d | 2003-10-13 22:26:55 +0000 | [diff] [blame] | 278 | switch(sig) { |
| 279 | case VKI_SIGSEGV: |
| 280 | case VKI_SIGBUS: |
| 281 | case VKI_SIGFPE: |
| 282 | case VKI_SIGILL: |
| 283 | /* For these, we always want to catch them and report, even |
| 284 | if the client code doesn't. */ |
| 285 | skss_handler = vg_sync_signalhandler; |
| 286 | break; |
| 287 | |
| 288 | case VKI_SIGVGINT: |
| 289 | case VKI_SIGVGKILL: |
| 290 | skss_handler = proxy_sigvg_handler; |
| 291 | break; |
| 292 | |
| 293 | case VKI_SIGCHLD: |
| 294 | if (scss_handler == VKI_SIG_IGN) { |
| 295 | skss_handler = vg_babyeater; |
| 296 | break; |
| 297 | } |
| 298 | /* FALLTHROUGH */ |
| 299 | default: |
| 300 | if (scss_handler == VKI_SIG_IGN) |
| 301 | skss_handler = VKI_SIG_IGN; |
| 302 | else |
| 303 | skss_handler = vg_async_signalhandler; |
| 304 | break; |
| 305 | } |
| 306 | |
sewardj | 018f762 | 2002-05-15 21:13:39 +0000 | [diff] [blame] | 307 | /* Restorer */ |
| 308 | /* |
| 309 | Doesn't seem like we can spin this one. |
| 310 | if (vg_scss.scss_per_sig[sig].scss_restorer != NULL) |
| 311 | VG_(unimplemented) |
| 312 | ("sigactions with non-NULL .sa_restorer field"); |
| 313 | */ |
| 314 | |
sewardj | 018f762 | 2002-05-15 21:13:39 +0000 | [diff] [blame] | 315 | /* Flags */ |
| 316 | |
| 317 | skss_flags = 0; |
jsgf | 855d93d | 2003-10-13 22:26:55 +0000 | [diff] [blame] | 318 | |
sewardj | 018f762 | 2002-05-15 21:13:39 +0000 | [diff] [blame] | 319 | /* SA_NOCLDSTOP: pass to kernel */ |
| 320 | if (scss_flags & VKI_SA_NOCLDSTOP) |
| 321 | skss_flags |= VKI_SA_NOCLDSTOP; |
jsgf | 855d93d | 2003-10-13 22:26:55 +0000 | [diff] [blame] | 322 | |
| 323 | /* SA_NOCLDWAIT - don't set */ |
| 324 | /* XXX we could set this if we're not using wait() ourselves for |
| 325 | tracking proxyLWPs (ie, have_futex is true in |
| 326 | vg_syscalls.c. */ |
| 327 | |
sewardj | 018f762 | 2002-05-15 21:13:39 +0000 | [diff] [blame] | 328 | /* SA_ONESHOT: ignore client setting */ |
| 329 | /* |
| 330 | if (!(scss_flags & VKI_SA_ONESHOT)) |
| 331 | VG_(unimplemented) |
| 332 | ("sigactions without SA_ONESHOT"); |
| 333 | vg_assert(scss_flags & VKI_SA_ONESHOT); |
| 334 | skss_flags |= VKI_SA_ONESHOT; |
| 335 | */ |
jsgf | 855d93d | 2003-10-13 22:26:55 +0000 | [diff] [blame] | 336 | |
| 337 | /* SA_RESTART: ignore client setting and always set it for us |
| 338 | (even though we never rely on the kernel to restart a |
| 339 | syscall, we observe whether it wanted to restart the syscall |
| 340 | or not, which guides our actions) */ |
sewardj | 018f762 | 2002-05-15 21:13:39 +0000 | [diff] [blame] | 341 | skss_flags |= VKI_SA_RESTART; |
jsgf | 855d93d | 2003-10-13 22:26:55 +0000 | [diff] [blame] | 342 | |
| 343 | /* SA_NOMASK: ignore it */ |
| 344 | |
sewardj | 2342c97 | 2002-05-22 23:34:20 +0000 | [diff] [blame] | 345 | /* SA_ONSTACK: client setting is irrelevant here */ |
| 346 | /* |
sewardj | 018f762 | 2002-05-15 21:13:39 +0000 | [diff] [blame] | 347 | if (scss_flags & VKI_SA_ONSTACK) |
| 348 | VG_(unimplemented) |
| 349 | ("signals on an alternative stack (SA_ONSTACK)"); |
| 350 | vg_assert(!(scss_flags & VKI_SA_ONSTACK)); |
sewardj | 2342c97 | 2002-05-22 23:34:20 +0000 | [diff] [blame] | 351 | */ |
sewardj | 018f762 | 2002-05-15 21:13:39 +0000 | [diff] [blame] | 352 | /* ... but WE ask for on-stack ourselves ... */ |
| 353 | skss_flags |= VKI_SA_ONSTACK; |
| 354 | |
jsgf | 855d93d | 2003-10-13 22:26:55 +0000 | [diff] [blame] | 355 | /* always ask for SA_SIGINFO */ |
| 356 | skss_flags |= VKI_SA_SIGINFO; |
sewardj | 018f762 | 2002-05-15 21:13:39 +0000 | [diff] [blame] | 357 | |
jsgf | 855d93d | 2003-10-13 22:26:55 +0000 | [diff] [blame] | 358 | /* Create SKSS entry for this signal. */ |
sewardj | 018f762 | 2002-05-15 21:13:39 +0000 | [diff] [blame] | 359 | |
sewardj | 6a3c26e | 2002-05-23 17:09:43 +0000 | [diff] [blame] | 360 | if (sig != VKI_SIGKILL && sig != VKI_SIGSTOP) |
| 361 | dst->skss_per_sig[sig].skss_handler = skss_handler; |
| 362 | else |
| 363 | dst->skss_per_sig[sig].skss_handler = VKI_SIG_DFL; |
| 364 | |
sewardj | 018f762 | 2002-05-15 21:13:39 +0000 | [diff] [blame] | 365 | dst->skss_per_sig[sig].skss_flags = skss_flags; |
| 366 | } |
| 367 | |
| 368 | /* Sanity checks. */ |
| 369 | vg_assert(dst->skss_per_sig[VKI_SIGKILL].skss_handler |
| 370 | == VKI_SIG_DFL); |
| 371 | vg_assert(dst->skss_per_sig[VKI_SIGSTOP].skss_handler |
| 372 | == VKI_SIG_DFL); |
sewardj | 018f762 | 2002-05-15 21:13:39 +0000 | [diff] [blame] | 373 | |
| 374 | if (0) |
| 375 | pp_SKSS(); |
| 376 | } |
| 377 | |
| 378 | |
| 379 | /* --------------------------------------------------------------------- |
| 380 | After a possible SCSS change, update SKSS and the kernel itself. |
| 381 | ------------------------------------------------------------------ */ |
| 382 | |
sewardj | 018f762 | 2002-05-15 21:13:39 +0000 | [diff] [blame] | 383 | void VG_(handle_SCSS_change) ( Bool force_update ) |
| 384 | { |
| 385 | Int res, sig; |
| 386 | SKSS skss_old; |
| 387 | vki_ksigaction ksa, ksa_old; |
| 388 | |
jsgf | 855d93d | 2003-10-13 22:26:55 +0000 | [diff] [blame] | 389 | vg_assert(is_correct_sigmask()); |
sewardj | 018f762 | 2002-05-15 21:13:39 +0000 | [diff] [blame] | 390 | |
| 391 | /* Remember old SKSS and calculate new one. */ |
| 392 | skss_old = vg_skss; |
| 393 | calculate_SKSS_from_SCSS ( &vg_skss ); |
| 394 | |
| 395 | /* Compare the new SKSS entries vs the old ones, and update kernel |
| 396 | where they differ. */ |
| 397 | for (sig = 1; sig <= VKI_KNSIG; sig++) { |
| 398 | |
| 399 | /* Trying to do anything with SIGKILL is pointless; just ignore |
| 400 | it. */ |
| 401 | if (sig == VKI_SIGKILL || sig == VKI_SIGSTOP) |
| 402 | continue; |
| 403 | |
sewardj | 018f762 | 2002-05-15 21:13:39 +0000 | [diff] [blame] | 404 | if (!force_update) { |
| 405 | if ((skss_old.skss_per_sig[sig].skss_handler |
| 406 | == vg_skss.skss_per_sig[sig].skss_handler) |
| 407 | && (skss_old.skss_per_sig[sig].skss_flags |
| 408 | == vg_skss.skss_per_sig[sig].skss_flags)) |
| 409 | /* no difference */ |
| 410 | continue; |
| 411 | } |
| 412 | |
| 413 | ksa.ksa_handler = vg_skss.skss_per_sig[sig].skss_handler; |
| 414 | ksa.ksa_flags = vg_skss.skss_per_sig[sig].skss_flags; |
| 415 | vg_assert(ksa.ksa_flags & VKI_SA_ONSTACK); |
| 416 | VG_(ksigfillset)( &ksa.ksa_mask ); |
| 417 | VG_(ksigdelset)( &ksa.ksa_mask, VKI_SIGKILL ); |
| 418 | VG_(ksigdelset)( &ksa.ksa_mask, VKI_SIGSTOP ); |
| 419 | ksa.ksa_restorer = NULL; |
| 420 | |
| 421 | if (VG_(clo_trace_signals)) |
| 422 | VG_(message)(Vg_DebugMsg, |
| 423 | "setting ksig %d to: hdlr 0x%x, flags 0x%x, " |
| 424 | "mask(63..0) 0x%x 0x%x", |
| 425 | sig, ksa.ksa_handler, |
| 426 | ksa.ksa_flags, |
| 427 | ksa.ksa_mask.ws[1], |
| 428 | ksa.ksa_mask.ws[0] |
| 429 | ); |
| 430 | |
| 431 | res = VG_(ksigaction)( sig, &ksa, &ksa_old ); |
| 432 | vg_assert(res == 0); |
| 433 | |
| 434 | /* Since we got the old sigaction more or less for free, might |
| 435 | as well extract the maximum sanity-check value from it. */ |
| 436 | if (!force_update) { |
| 437 | vg_assert(ksa_old.ksa_handler |
| 438 | == skss_old.skss_per_sig[sig].skss_handler); |
| 439 | vg_assert(ksa_old.ksa_flags |
| 440 | == skss_old.skss_per_sig[sig].skss_flags); |
| 441 | vg_assert(ksa_old.ksa_restorer |
| 442 | == NULL); |
| 443 | VG_(ksigaddset)( &ksa_old.ksa_mask, VKI_SIGKILL ); |
| 444 | VG_(ksigaddset)( &ksa_old.ksa_mask, VKI_SIGSTOP ); |
| 445 | vg_assert(VG_(kisfullsigset)( &ksa_old.ksa_mask )); |
| 446 | } |
| 447 | } |
sewardj | 018f762 | 2002-05-15 21:13:39 +0000 | [diff] [blame] | 448 | } |
| 449 | |
| 450 | |
| 451 | /* --------------------------------------------------------------------- |
| 452 | Update/query SCSS in accordance with client requests. |
| 453 | ------------------------------------------------------------------ */ |
| 454 | |
sewardj | 2342c97 | 2002-05-22 23:34:20 +0000 | [diff] [blame] | 455 | /* Logic for this alt-stack stuff copied directly from do_sigaltstack |
| 456 | in kernel/signal.[ch] */ |
| 457 | |
| 458 | /* True if we are on the alternate signal stack. */ |
| 459 | static Int on_sig_stack ( Addr m_esp ) |
| 460 | { |
| 461 | return (m_esp - (Addr)vg_scss.altstack.ss_sp |
| 462 | < vg_scss.altstack.ss_size); |
| 463 | } |
| 464 | |
| 465 | static Int sas_ss_flags ( Addr m_esp ) |
| 466 | { |
| 467 | return (vg_scss.altstack.ss_size == 0 |
| 468 | ? VKI_SS_DISABLE |
| 469 | : on_sig_stack(m_esp) ? VKI_SS_ONSTACK : 0); |
| 470 | } |
| 471 | |
| 472 | |
| 473 | void VG_(do__NR_sigaltstack) ( ThreadId tid ) |
| 474 | { |
| 475 | vki_kstack_t* ss; |
| 476 | vki_kstack_t* oss; |
| 477 | Addr m_esp; |
| 478 | |
| 479 | vg_assert(VG_(is_valid_tid)(tid)); |
| 480 | ss = (vki_kstack_t*)(VG_(threads)[tid].m_ebx); |
| 481 | oss = (vki_kstack_t*)(VG_(threads)[tid].m_ecx); |
| 482 | m_esp = VG_(threads)[tid].m_esp; |
| 483 | |
| 484 | if (VG_(clo_trace_signals)) |
| 485 | VG_(message)(Vg_DebugExtraMsg, |
| 486 | "__NR_sigaltstack: tid %d, " |
| 487 | "ss 0x%x, oss 0x%x (current %%esp %p)", |
| 488 | tid, (UInt)ss, (UInt)oss, (UInt)m_esp ); |
| 489 | |
| 490 | if (oss != NULL) { |
| 491 | oss->ss_sp = vg_scss.altstack.ss_sp; |
| 492 | oss->ss_size = vg_scss.altstack.ss_size; |
jsgf | 855d93d | 2003-10-13 22:26:55 +0000 | [diff] [blame] | 493 | oss->ss_flags = vg_scss.altstack.ss_flags | sas_ss_flags(m_esp); |
sewardj | 2342c97 | 2002-05-22 23:34:20 +0000 | [diff] [blame] | 494 | } |
| 495 | |
| 496 | if (ss != NULL) { |
| 497 | if (on_sig_stack(VG_(threads)[tid].m_esp)) { |
njn | d304045 | 2003-05-19 15:04:06 +0000 | [diff] [blame] | 498 | SET_SYSCALL_RETVAL(tid, -VKI_EPERM); |
sewardj | 2342c97 | 2002-05-22 23:34:20 +0000 | [diff] [blame] | 499 | return; |
| 500 | } |
| 501 | if (ss->ss_flags != VKI_SS_DISABLE |
| 502 | && ss->ss_flags != VKI_SS_ONSTACK |
| 503 | && ss->ss_flags != 0) { |
njn | d304045 | 2003-05-19 15:04:06 +0000 | [diff] [blame] | 504 | SET_SYSCALL_RETVAL(tid, -VKI_EINVAL); |
sewardj | 2342c97 | 2002-05-22 23:34:20 +0000 | [diff] [blame] | 505 | return; |
| 506 | } |
| 507 | if (ss->ss_flags == VKI_SS_DISABLE) { |
jsgf | 855d93d | 2003-10-13 22:26:55 +0000 | [diff] [blame] | 508 | vg_scss.altstack.ss_flags = VKI_SS_DISABLE; |
sewardj | 2342c97 | 2002-05-22 23:34:20 +0000 | [diff] [blame] | 509 | } else { |
| 510 | if (ss->ss_size < VKI_MINSIGSTKSZ) { |
njn | d304045 | 2003-05-19 15:04:06 +0000 | [diff] [blame] | 511 | SET_SYSCALL_RETVAL(tid, -VKI_ENOMEM); |
sewardj | 2342c97 | 2002-05-22 23:34:20 +0000 | [diff] [blame] | 512 | return; |
| 513 | } |
jsgf | 855d93d | 2003-10-13 22:26:55 +0000 | [diff] [blame] | 514 | |
| 515 | vg_scss.altstack.ss_sp = ss->ss_sp; |
| 516 | vg_scss.altstack.ss_size = ss->ss_size; |
| 517 | vg_scss.altstack.ss_flags = 0; |
sewardj | 2342c97 | 2002-05-22 23:34:20 +0000 | [diff] [blame] | 518 | } |
sewardj | 2342c97 | 2002-05-22 23:34:20 +0000 | [diff] [blame] | 519 | } |
njn | d304045 | 2003-05-19 15:04:06 +0000 | [diff] [blame] | 520 | SET_SYSCALL_RETVAL(tid, 0); |
sewardj | 2342c97 | 2002-05-22 23:34:20 +0000 | [diff] [blame] | 521 | } |
| 522 | |
| 523 | |
sewardj | 018f762 | 2002-05-15 21:13:39 +0000 | [diff] [blame] | 524 | void VG_(do__NR_sigaction) ( ThreadId tid ) |
| 525 | { |
| 526 | Int signo; |
| 527 | vki_ksigaction* new_act; |
| 528 | vki_ksigaction* old_act; |
jsgf | 855d93d | 2003-10-13 22:26:55 +0000 | [diff] [blame] | 529 | |
| 530 | vg_assert(is_correct_sigmask()); |
sewardj | 018f762 | 2002-05-15 21:13:39 +0000 | [diff] [blame] | 531 | |
| 532 | vg_assert(VG_(is_valid_tid)(tid)); |
| 533 | signo = VG_(threads)[tid].m_ebx; /* int sigNo */ |
| 534 | new_act = (vki_ksigaction*)(VG_(threads)[tid].m_ecx); |
| 535 | old_act = (vki_ksigaction*)(VG_(threads)[tid].m_edx); |
| 536 | |
| 537 | if (VG_(clo_trace_signals)) |
| 538 | VG_(message)(Vg_DebugExtraMsg, |
| 539 | "__NR_sigaction: tid %d, sigNo %d, " |
| 540 | "new 0x%x, old 0x%x, new flags 0x%x", |
| 541 | tid, signo, (UInt)new_act, (UInt)old_act, |
| 542 | (UInt)(new_act ? new_act->ksa_flags : 0) ); |
| 543 | |
| 544 | /* Rule out various error conditions. The aim is to ensure that if |
| 545 | when the call is passed to the kernel it will definitely |
| 546 | succeed. */ |
| 547 | |
| 548 | /* Reject out-of-range signal numbers. */ |
| 549 | if (signo < 1 || signo > VKI_KNSIG) goto bad_signo; |
| 550 | |
jsgf | 855d93d | 2003-10-13 22:26:55 +0000 | [diff] [blame] | 551 | /* don't let them use our signals */ |
| 552 | if ( (signo == VKI_SIGVGINT || signo == VKI_SIGVGKILL) |
| 553 | && new_act |
| 554 | && !(new_act->ksa_handler == VKI_SIG_DFL || new_act->ksa_handler == VKI_SIG_IGN) ) |
| 555 | goto bad_signo; |
| 556 | |
sewardj | 018f762 | 2002-05-15 21:13:39 +0000 | [diff] [blame] | 557 | /* Reject attempts to set a handler (or set ignore) for SIGKILL. */ |
| 558 | if ( (signo == VKI_SIGKILL || signo == VKI_SIGSTOP) |
| 559 | && new_act |
| 560 | && new_act->ksa_handler != VKI_SIG_DFL) |
| 561 | goto bad_sigkill_or_sigstop; |
| 562 | |
| 563 | /* If the client supplied non-NULL old_act, copy the relevant SCSS |
| 564 | entry into it. */ |
| 565 | if (old_act) { |
| 566 | old_act->ksa_handler = vg_scss.scss_per_sig[signo].scss_handler; |
| 567 | old_act->ksa_flags = vg_scss.scss_per_sig[signo].scss_flags; |
| 568 | old_act->ksa_mask = vg_scss.scss_per_sig[signo].scss_mask; |
| 569 | old_act->ksa_restorer = vg_scss.scss_per_sig[signo].scss_restorer; |
| 570 | } |
| 571 | |
| 572 | /* And now copy new SCSS entry from new_act. */ |
| 573 | if (new_act) { |
| 574 | vg_scss.scss_per_sig[signo].scss_handler = new_act->ksa_handler; |
| 575 | vg_scss.scss_per_sig[signo].scss_flags = new_act->ksa_flags; |
| 576 | vg_scss.scss_per_sig[signo].scss_mask = new_act->ksa_mask; |
| 577 | vg_scss.scss_per_sig[signo].scss_restorer = new_act->ksa_restorer; |
| 578 | } |
| 579 | |
| 580 | /* All happy bunnies ... */ |
| 581 | if (new_act) { |
sewardj | 018f762 | 2002-05-15 21:13:39 +0000 | [diff] [blame] | 582 | VG_(handle_SCSS_change)( False /* lazy update */ ); |
| 583 | } |
njn | d304045 | 2003-05-19 15:04:06 +0000 | [diff] [blame] | 584 | SET_SYSCALL_RETVAL(tid, 0); |
sewardj | 018f762 | 2002-05-15 21:13:39 +0000 | [diff] [blame] | 585 | return; |
| 586 | |
| 587 | bad_signo: |
sewardj | 37d06f2 | 2003-09-17 21:48:26 +0000 | [diff] [blame] | 588 | if (VG_(needs).core_errors && VG_(clo_verbosity) >= 1) |
njn25 | e49d8e7 | 2002-09-23 09:36:25 +0000 | [diff] [blame] | 589 | VG_(message)(Vg_UserMsg, |
| 590 | "Warning: bad signal number %d in __NR_sigaction.", |
| 591 | signo); |
njn | d304045 | 2003-05-19 15:04:06 +0000 | [diff] [blame] | 592 | SET_SYSCALL_RETVAL(tid, -VKI_EINVAL); |
sewardj | 018f762 | 2002-05-15 21:13:39 +0000 | [diff] [blame] | 593 | return; |
| 594 | |
| 595 | bad_sigkill_or_sigstop: |
sewardj | 37d06f2 | 2003-09-17 21:48:26 +0000 | [diff] [blame] | 596 | if (VG_(needs).core_errors && VG_(clo_verbosity) >= 1) |
njn25 | e49d8e7 | 2002-09-23 09:36:25 +0000 | [diff] [blame] | 597 | VG_(message)(Vg_UserMsg, |
jsgf | 855d93d | 2003-10-13 22:26:55 +0000 | [diff] [blame] | 598 | "Warning: attempt to set %s handler in __NR_sigaction.", |
| 599 | signame(signo)); |
sewardj | 018f762 | 2002-05-15 21:13:39 +0000 | [diff] [blame] | 600 | |
njn | d304045 | 2003-05-19 15:04:06 +0000 | [diff] [blame] | 601 | SET_SYSCALL_RETVAL(tid, -VKI_EINVAL); |
sewardj | 018f762 | 2002-05-15 21:13:39 +0000 | [diff] [blame] | 602 | return; |
| 603 | } |
| 604 | |
| 605 | |
| 606 | static |
| 607 | void do_sigprocmask_bitops ( Int vki_how, |
| 608 | vki_ksigset_t* orig_set, |
| 609 | vki_ksigset_t* modifier ) |
| 610 | { |
| 611 | switch (vki_how) { |
| 612 | case VKI_SIG_BLOCK: |
| 613 | VG_(ksigaddset_from_set)( orig_set, modifier ); |
| 614 | break; |
| 615 | case VKI_SIG_UNBLOCK: |
| 616 | VG_(ksigdelset_from_set)( orig_set, modifier ); |
| 617 | break; |
| 618 | case VKI_SIG_SETMASK: |
| 619 | *orig_set = *modifier; |
| 620 | break; |
| 621 | default: |
njn | e427a66 | 2002-10-02 11:08:25 +0000 | [diff] [blame] | 622 | VG_(core_panic)("do_sigprocmask_bitops"); |
sewardj | 018f762 | 2002-05-15 21:13:39 +0000 | [diff] [blame] | 623 | break; |
| 624 | } |
| 625 | } |
| 626 | |
jsgf | 855d93d | 2003-10-13 22:26:55 +0000 | [diff] [blame] | 627 | /* |
| 628 | This updates the thread's signal mask. There's no such thing as a |
| 629 | process-wide signal mask. |
sewardj | 018f762 | 2002-05-15 21:13:39 +0000 | [diff] [blame] | 630 | |
| 631 | Note that the thread signal masks are an implicit part of SCSS, |
| 632 | which is why this routine is allowed to mess with them. |
| 633 | */ |
| 634 | static |
| 635 | void do_setmask ( ThreadId tid, |
| 636 | Int how, |
| 637 | vki_ksigset_t* newset, |
| 638 | vki_ksigset_t* oldset ) |
| 639 | { |
jsgf | 855d93d | 2003-10-13 22:26:55 +0000 | [diff] [blame] | 640 | vg_assert(is_correct_sigmask()); |
sewardj | 018f762 | 2002-05-15 21:13:39 +0000 | [diff] [blame] | 641 | |
| 642 | if (VG_(clo_trace_signals)) |
sewardj | a464e5c | 2002-05-23 17:34:49 +0000 | [diff] [blame] | 643 | VG_(message)(Vg_DebugExtraMsg, |
jsgf | 855d93d | 2003-10-13 22:26:55 +0000 | [diff] [blame] | 644 | "do_setmask: tid = %d how = %d (%s), set = %p %08x%08x", |
| 645 | tid, how, |
| 646 | how==VKI_SIG_BLOCK ? "SIG_BLOCK" : ( |
| 647 | how==VKI_SIG_UNBLOCK ? "SIG_UNBLOCK" : ( |
| 648 | how==VKI_SIG_SETMASK ? "SIG_SETMASK" : "???")), |
| 649 | newset, newset ? newset->ws[1] : 0, newset ? newset->ws[0] : 0 |
| 650 | ); |
sewardj | 018f762 | 2002-05-15 21:13:39 +0000 | [diff] [blame] | 651 | |
jsgf | 855d93d | 2003-10-13 22:26:55 +0000 | [diff] [blame] | 652 | /* Just do this thread. */ |
| 653 | vg_assert(VG_(is_valid_tid)(tid)); |
| 654 | if (oldset) { |
| 655 | *oldset = VG_(threads)[tid].eff_sig_mask; |
| 656 | if (VG_(clo_trace_signals)) |
| 657 | VG_(message)(Vg_DebugExtraMsg, |
| 658 | "\toldset=%p %08x%08x", |
| 659 | oldset, oldset->ws[1], oldset->ws[0]); |
sewardj | 018f762 | 2002-05-15 21:13:39 +0000 | [diff] [blame] | 660 | } |
sewardj | 018f762 | 2002-05-15 21:13:39 +0000 | [diff] [blame] | 661 | if (newset) { |
jsgf | 855d93d | 2003-10-13 22:26:55 +0000 | [diff] [blame] | 662 | do_sigprocmask_bitops (how, &VG_(threads)[tid].sig_mask, newset ); |
| 663 | VG_(ksigdelset)(&VG_(threads)[tid].sig_mask, VKI_SIGKILL); |
| 664 | VG_(ksigdelset)(&VG_(threads)[tid].sig_mask, VKI_SIGSTOP); |
| 665 | VG_(proxy_setsigmask)(tid); |
sewardj | 018f762 | 2002-05-15 21:13:39 +0000 | [diff] [blame] | 666 | } |
jsgf | 855d93d | 2003-10-13 22:26:55 +0000 | [diff] [blame] | 667 | |
| 668 | vg_assert(is_correct_sigmask()); |
sewardj | 018f762 | 2002-05-15 21:13:39 +0000 | [diff] [blame] | 669 | } |
| 670 | |
| 671 | |
| 672 | void VG_(do__NR_sigprocmask) ( ThreadId tid, |
| 673 | Int how, |
| 674 | vki_ksigset_t* set, |
| 675 | vki_ksigset_t* oldset ) |
| 676 | { |
jsgf | 855d93d | 2003-10-13 22:26:55 +0000 | [diff] [blame] | 677 | switch(how) { |
| 678 | case VKI_SIG_BLOCK: |
| 679 | case VKI_SIG_UNBLOCK: |
| 680 | case VKI_SIG_SETMASK: |
sewardj | 018f762 | 2002-05-15 21:13:39 +0000 | [diff] [blame] | 681 | vg_assert(VG_(is_valid_tid)(tid)); |
jsgf | 855d93d | 2003-10-13 22:26:55 +0000 | [diff] [blame] | 682 | /* Syscall returns 0 (success) to its thread. Set this up before |
| 683 | calling do_setmask() because we may get a signal as part of |
| 684 | setting the mask, which will confuse things. |
| 685 | */ |
njn | d304045 | 2003-05-19 15:04:06 +0000 | [diff] [blame] | 686 | SET_SYSCALL_RETVAL(tid, 0); |
jsgf | 855d93d | 2003-10-13 22:26:55 +0000 | [diff] [blame] | 687 | do_setmask ( tid, how, set, oldset ); |
| 688 | |
| 689 | VG_(route_signals)(); /* if we're routing, do something before returning */ |
| 690 | break; |
| 691 | |
| 692 | default: |
sewardj | 018f762 | 2002-05-15 21:13:39 +0000 | [diff] [blame] | 693 | VG_(message)(Vg_DebugMsg, |
| 694 | "sigprocmask: unknown `how' field %d", how); |
njn | d304045 | 2003-05-19 15:04:06 +0000 | [diff] [blame] | 695 | SET_SYSCALL_RETVAL(tid, -VKI_EINVAL); |
jsgf | 855d93d | 2003-10-13 22:26:55 +0000 | [diff] [blame] | 696 | break; |
sewardj | 018f762 | 2002-05-15 21:13:39 +0000 | [diff] [blame] | 697 | } |
| 698 | } |
| 699 | |
| 700 | |
| 701 | void VG_(do_pthread_sigmask_SCSS_upd) ( ThreadId tid, |
| 702 | Int how, |
| 703 | vki_ksigset_t* set, |
| 704 | vki_ksigset_t* oldset ) |
| 705 | { |
| 706 | /* Assume that how has been validated by caller. */ |
| 707 | vg_assert(how == VKI_SIG_BLOCK || how == VKI_SIG_UNBLOCK |
| 708 | || how == VKI_SIG_SETMASK); |
| 709 | vg_assert(VG_(is_valid_tid)(tid)); |
| 710 | do_setmask ( tid, how, set, oldset ); |
| 711 | /* The request return code is set in do_pthread_sigmask */ |
| 712 | } |
| 713 | |
| 714 | |
| 715 | void VG_(send_signal_to_thread) ( ThreadId thread, Int sig ) |
| 716 | { |
jsgf | 855d93d | 2003-10-13 22:26:55 +0000 | [diff] [blame] | 717 | ThreadState *tst; |
| 718 | |
sewardj | 018f762 | 2002-05-15 21:13:39 +0000 | [diff] [blame] | 719 | vg_assert(VG_(is_valid_tid)(thread)); |
| 720 | vg_assert(sig >= 1 && sig <= VKI_KNSIG); |
| 721 | |
jsgf | 855d93d | 2003-10-13 22:26:55 +0000 | [diff] [blame] | 722 | tst = VG_(get_ThreadState)(thread); |
| 723 | vg_assert(tst->proxy != NULL); |
sewardj | 018f762 | 2002-05-15 21:13:39 +0000 | [diff] [blame] | 724 | |
jsgf | 855d93d | 2003-10-13 22:26:55 +0000 | [diff] [blame] | 725 | VG_(proxy_sendsig)(thread, sig); |
sewardj | efbfcdf | 2002-06-19 17:35:45 +0000 | [diff] [blame] | 726 | } |
| 727 | |
| 728 | |
sewardj | 018f762 | 2002-05-15 21:13:39 +0000 | [diff] [blame] | 729 | /* --------------------------------------------------------------------- |
| 730 | LOW LEVEL STUFF TO DO WITH SIGNALS: IMPLEMENTATION |
| 731 | ------------------------------------------------------------------ */ |
sewardj | 77e466c | 2002-04-14 02:29:29 +0000 | [diff] [blame] | 732 | |
sewardj | 2e93c50 | 2002-04-12 11:12:52 +0000 | [diff] [blame] | 733 | /* --------------------------------------------------------------------- |
| 734 | Handy utilities to block/restore all host signals. |
| 735 | ------------------------------------------------------------------ */ |
| 736 | |
| 737 | /* Block all host signals, dumping the old mask in *saved_mask. */ |
| 738 | void VG_(block_all_host_signals) ( /* OUT */ vki_ksigset_t* saved_mask ) |
| 739 | { |
| 740 | Int ret; |
| 741 | vki_ksigset_t block_procmask; |
| 742 | VG_(ksigfillset)(&block_procmask); |
| 743 | ret = VG_(ksigprocmask) |
| 744 | (VKI_SIG_SETMASK, &block_procmask, saved_mask); |
| 745 | vg_assert(ret == 0); |
| 746 | } |
| 747 | |
| 748 | /* Restore the blocking mask using the supplied saved one. */ |
sewardj | 018f762 | 2002-05-15 21:13:39 +0000 | [diff] [blame] | 749 | void VG_(restore_all_host_signals) ( /* IN */ vki_ksigset_t* saved_mask ) |
sewardj | 2e93c50 | 2002-04-12 11:12:52 +0000 | [diff] [blame] | 750 | { |
| 751 | Int ret; |
| 752 | ret = VG_(ksigprocmask)(VKI_SIG_SETMASK, saved_mask, NULL); |
| 753 | vg_assert(ret == 0); |
| 754 | } |
sewardj | de4a1d0 | 2002-03-22 01:27:54 +0000 | [diff] [blame] | 755 | |
jsgf | 855d93d | 2003-10-13 22:26:55 +0000 | [diff] [blame] | 756 | /* Sanity check - check the scheduler LWP has all the signals blocked |
| 757 | it is supposed to have blocked. */ |
| 758 | static Bool is_correct_sigmask(void) |
| 759 | { |
| 760 | vki_ksigset_t mask; |
| 761 | Bool ret = True; |
| 762 | |
| 763 | vg_assert(VG_(gettid)() == VG_(main_pid)); |
| 764 | |
| 765 | #ifdef DEBUG_SIGNALS |
| 766 | VG_(ksigprocmask)(VKI_SIG_SETMASK, NULL, &mask); |
| 767 | |
| 768 | /* unresumable signals */ |
| 769 | |
| 770 | ret = ret && !VG_(ksigismember)(&mask, VKI_SIGSEGV); |
| 771 | VG_(ksigaddset)(&mask, VKI_SIGSEGV); |
| 772 | |
| 773 | ret = ret && !VG_(ksigismember)(&mask, VKI_SIGBUS); |
| 774 | VG_(ksigaddset)(&mask, VKI_SIGBUS); |
| 775 | |
| 776 | ret = ret && !VG_(ksigismember)(&mask, VKI_SIGFPE); |
| 777 | VG_(ksigaddset)(&mask, VKI_SIGFPE); |
| 778 | |
| 779 | ret = ret && !VG_(ksigismember)(&mask, VKI_SIGILL); |
| 780 | VG_(ksigaddset)(&mask, VKI_SIGILL); |
| 781 | |
| 782 | /* unblockable signals (doesn't really matter if these are |
| 783 | already present) */ |
| 784 | VG_(ksigaddset)(&mask, VKI_SIGSTOP); |
| 785 | VG_(ksigaddset)(&mask, VKI_SIGKILL); |
| 786 | |
| 787 | ret = ret && VG_(kisfullsigset)(&mask); |
| 788 | #endif /* DEBUG_SIGNALS */ |
| 789 | |
| 790 | return ret; |
| 791 | } |
| 792 | |
| 793 | /* Set the signal mask for the scheduer LWP; this should be set once |
| 794 | and left that way - all async signal handling is done in the proxy |
| 795 | LWPs. */ |
| 796 | static void set_main_sigmask(void) |
| 797 | { |
| 798 | vki_ksigset_t mask; |
| 799 | |
| 800 | VG_(ksigfillset)(&mask); |
| 801 | VG_(ksigdelset)(&mask, VKI_SIGSEGV); |
| 802 | VG_(ksigdelset)(&mask, VKI_SIGBUS); |
| 803 | VG_(ksigdelset)(&mask, VKI_SIGFPE); |
| 804 | VG_(ksigdelset)(&mask, VKI_SIGILL); |
| 805 | |
| 806 | VG_(ksigprocmask)(VKI_SIG_SETMASK, &mask, NULL); |
| 807 | |
| 808 | vg_assert(is_correct_sigmask()); |
| 809 | } |
sewardj | de4a1d0 | 2002-03-22 01:27:54 +0000 | [diff] [blame] | 810 | |
| 811 | /* --------------------------------------------------------------------- |
| 812 | The signal simulation proper. A simplified version of what the |
| 813 | Linux kernel does. |
| 814 | ------------------------------------------------------------------ */ |
| 815 | |
| 816 | /* A structure in which to save the application's registers |
| 817 | during the execution of signal handlers. */ |
| 818 | |
| 819 | typedef |
| 820 | struct { |
jsgf | 855d93d | 2003-10-13 22:26:55 +0000 | [diff] [blame] | 821 | /* There are two different stack frame formats, depending on |
| 822 | whether the client set the SA_SIGINFO flag for the handler. |
| 823 | This structure is put onto the client's stack as part of |
| 824 | signal delivery, and therefore appears as the signal |
| 825 | handler's arguments. |
| 826 | |
| 827 | The first two words are common for both frame formats - |
| 828 | they're the return address and the signal number. */ |
sewardj | f247eae | 2002-09-27 00:46:59 +0000 | [diff] [blame] | 829 | |
| 830 | /* Sig handler's (bogus) return address */ |
| 831 | Addr retaddr; |
| 832 | /* The arg to the sig handler. We need to inspect this after |
| 833 | the handler returns, but it's unreasonable to assume that the |
| 834 | handler won't change it. So we keep a second copy of it in |
| 835 | sigNo_private. */ |
| 836 | Int sigNo; |
jsgf | 855d93d | 2003-10-13 22:26:55 +0000 | [diff] [blame] | 837 | |
| 838 | /* This is where the two frames start differing. */ |
| 839 | union { |
| 840 | struct { /* set SA_SIGINFO */ |
| 841 | /* ptr to siginfo_t. */ |
| 842 | Addr psigInfo; |
| 843 | |
| 844 | /* ptr to ucontext */ |
| 845 | Addr puContext; |
| 846 | } sigInfo; |
| 847 | struct vki_sigcontext sigContext; /* did not set SA_SIGINFO */ |
| 848 | } handlerArgs; |
sewardj | f247eae | 2002-09-27 00:46:59 +0000 | [diff] [blame] | 849 | |
| 850 | /* The rest are private fields which the handler is unaware of. */ |
| 851 | |
sewardj | 2e93c50 | 2002-04-12 11:12:52 +0000 | [diff] [blame] | 852 | /* Sanity check word. */ |
sewardj | de4a1d0 | 2002-03-22 01:27:54 +0000 | [diff] [blame] | 853 | UInt magicPI; |
jsgf | 855d93d | 2003-10-13 22:26:55 +0000 | [diff] [blame] | 854 | /* pointed to by psigInfo */ |
| 855 | vki_ksiginfo_t sigInfo; |
| 856 | /* pointed to by puContext */ |
| 857 | struct vki_ucontext uContext; |
| 858 | |
sewardj | f247eae | 2002-09-27 00:46:59 +0000 | [diff] [blame] | 859 | /* Safely-saved version of sigNo, as described above. */ |
| 860 | Int sigNo_private; |
sewardj | 2e93c50 | 2002-04-12 11:12:52 +0000 | [diff] [blame] | 861 | /* Saved processor state. */ |
njn | d304045 | 2003-05-19 15:04:06 +0000 | [diff] [blame] | 862 | UInt m_sse[VG_SIZE_OF_SSESTATE_W]; |
| 863 | |
| 864 | UInt m_eax; |
| 865 | UInt m_ecx; |
| 866 | UInt m_edx; |
| 867 | UInt m_ebx; |
| 868 | UInt m_ebp; |
| 869 | UInt m_esp; |
| 870 | UInt m_esi; |
| 871 | UInt m_edi; |
| 872 | UInt m_eflags; |
| 873 | Addr m_eip; |
| 874 | |
| 875 | UInt sh_eax; |
| 876 | UInt sh_ebx; |
| 877 | UInt sh_ecx; |
| 878 | UInt sh_edx; |
| 879 | UInt sh_esi; |
| 880 | UInt sh_edi; |
| 881 | UInt sh_ebp; |
| 882 | UInt sh_esp; |
| 883 | UInt sh_eflags; |
| 884 | |
jsgf | 855d93d | 2003-10-13 22:26:55 +0000 | [diff] [blame] | 885 | /* saved signal mask to be restored when handler returns */ |
| 886 | vki_ksigset_t mask; |
| 887 | |
sewardj | 2e93c50 | 2002-04-12 11:12:52 +0000 | [diff] [blame] | 888 | /* Scheduler-private stuff: what was the thread's status prior to |
| 889 | delivering this signal? */ |
| 890 | ThreadStatus status; |
| 891 | /* Sanity check word. Is the highest-addressed word; do not |
| 892 | move!*/ |
sewardj | de4a1d0 | 2002-03-22 01:27:54 +0000 | [diff] [blame] | 893 | UInt magicE; |
| 894 | } |
sewardj | 2e93c50 | 2002-04-12 11:12:52 +0000 | [diff] [blame] | 895 | VgSigFrame; |
sewardj | de4a1d0 | 2002-03-22 01:27:54 +0000 | [diff] [blame] | 896 | |
| 897 | |
jsgf | 855d93d | 2003-10-13 22:26:55 +0000 | [diff] [blame] | 898 | /* Make up a plausible-looking thread state from the thread's current state */ |
| 899 | static void synth_ucontext(ThreadId tid, const vki_ksiginfo_t *si, |
| 900 | const vki_ksigset_t *set, struct vki_ucontext *uc) |
| 901 | { |
| 902 | ThreadState *tst = VG_(get_ThreadState)(tid); |
| 903 | struct vki_sigcontext *sc = &uc->uc_mcontext; |
| 904 | |
| 905 | VG_(memset)(uc, 0, sizeof(*uc)); |
| 906 | |
| 907 | uc->uc_flags = 0; |
| 908 | uc->uc_link = 0; |
| 909 | uc->uc_sigmask = *set; |
| 910 | uc->uc_stack = vg_scss.altstack; |
| 911 | |
| 912 | #define SC(reg) sc->reg = tst->m_##reg |
| 913 | SC(gs); |
| 914 | SC(fs); |
| 915 | SC(es); |
| 916 | SC(ds); |
| 917 | |
| 918 | SC(edi); |
| 919 | SC(esi); |
| 920 | SC(ebp); |
| 921 | SC(esp); |
| 922 | SC(ebx); |
| 923 | SC(edx); |
| 924 | SC(ecx); |
| 925 | SC(eax); |
| 926 | |
| 927 | SC(eip); |
| 928 | SC(cs); |
| 929 | SC(eflags); |
| 930 | SC(ss); |
| 931 | /* XXX esp_at_signal */ |
| 932 | /* XXX trapno */ |
| 933 | /* XXX err */ |
| 934 | #undef SC |
| 935 | |
| 936 | sc->cr2 = (UInt)si->_sifields._sigfault._addr; |
| 937 | } |
sewardj | de4a1d0 | 2002-03-22 01:27:54 +0000 | [diff] [blame] | 938 | |
sewardj | de4a1d0 | 2002-03-22 01:27:54 +0000 | [diff] [blame] | 939 | /* Set up a stack frame (VgSigContext) for the client's signal |
| 940 | handler. This includes the signal number and a bogus return |
| 941 | address. */ |
| 942 | static |
jsgf | 855d93d | 2003-10-13 22:26:55 +0000 | [diff] [blame] | 943 | void vg_push_signal_frame ( ThreadId tid, const vki_ksiginfo_t *siginfo ) |
sewardj | de4a1d0 | 2002-03-22 01:27:54 +0000 | [diff] [blame] | 944 | { |
| 945 | Int i; |
sewardj | 2342c97 | 2002-05-22 23:34:20 +0000 | [diff] [blame] | 946 | Addr esp, esp_top_of_frame; |
sewardj | 2e93c50 | 2002-04-12 11:12:52 +0000 | [diff] [blame] | 947 | VgSigFrame* frame; |
| 948 | ThreadState* tst; |
jsgf | 855d93d | 2003-10-13 22:26:55 +0000 | [diff] [blame] | 949 | Int sigNo = siginfo->si_signo; |
sewardj | 2e93c50 | 2002-04-12 11:12:52 +0000 | [diff] [blame] | 950 | |
sewardj | 2342c97 | 2002-05-22 23:34:20 +0000 | [diff] [blame] | 951 | vg_assert(sigNo >= 1 && sigNo <= VKI_KNSIG); |
sewardj | 018f762 | 2002-05-15 21:13:39 +0000 | [diff] [blame] | 952 | vg_assert(VG_(is_valid_tid)(tid)); |
| 953 | tst = & VG_(threads)[tid]; |
sewardj | 2e93c50 | 2002-04-12 11:12:52 +0000 | [diff] [blame] | 954 | |
jsgf | 855d93d | 2003-10-13 22:26:55 +0000 | [diff] [blame] | 955 | if (VG_(clo_trace_signals)) |
| 956 | VG_(message)(Vg_DebugMsg, |
| 957 | "vg_push_signal_frame (thread %d): signal %d", tid, sigNo); |
| 958 | |
sewardj | 2342c97 | 2002-05-22 23:34:20 +0000 | [diff] [blame] | 959 | if (/* this signal asked to run on an alt stack */ |
jsgf | 855d93d | 2003-10-13 22:26:55 +0000 | [diff] [blame] | 960 | (vg_scss.scss_per_sig[sigNo].scss_flags & VKI_SA_ONSTACK ) |
sewardj | 2342c97 | 2002-05-22 23:34:20 +0000 | [diff] [blame] | 961 | && /* there is a defined and enabled alt stack, which we're not |
| 962 | already using. Logic from get_sigframe in |
| 963 | arch/i386/kernel/signal.c. */ |
| 964 | sas_ss_flags(tst->m_esp) == 0 |
| 965 | ) { |
| 966 | esp_top_of_frame |
| 967 | = (Addr)(vg_scss.altstack.ss_sp) + vg_scss.altstack.ss_size; |
| 968 | if (VG_(clo_trace_signals)) |
| 969 | VG_(message)(Vg_DebugMsg, |
jsgf | 855d93d | 2003-10-13 22:26:55 +0000 | [diff] [blame] | 970 | "delivering signal %d (%s) to thread %d: on ALT STACK", |
| 971 | sigNo, signame(sigNo), tid ); |
njn | fdc28af | 2003-02-24 10:36:48 +0000 | [diff] [blame] | 972 | |
| 973 | /* Signal delivery to skins */ |
| 974 | VG_TRACK( pre_deliver_signal, tid, sigNo, /*alt_stack*/False ); |
| 975 | |
sewardj | 2342c97 | 2002-05-22 23:34:20 +0000 | [diff] [blame] | 976 | } else { |
| 977 | esp_top_of_frame = tst->m_esp; |
njn | fdc28af | 2003-02-24 10:36:48 +0000 | [diff] [blame] | 978 | |
| 979 | /* Signal delivery to skins */ |
| 980 | VG_TRACK( pre_deliver_signal, tid, sigNo, /*alt_stack*/True ); |
sewardj | 2342c97 | 2002-05-22 23:34:20 +0000 | [diff] [blame] | 981 | } |
| 982 | |
| 983 | esp = esp_top_of_frame; |
sewardj | 2e93c50 | 2002-04-12 11:12:52 +0000 | [diff] [blame] | 984 | esp -= sizeof(VgSigFrame); |
| 985 | frame = (VgSigFrame*)esp; |
njn25 | e49d8e7 | 2002-09-23 09:36:25 +0000 | [diff] [blame] | 986 | |
| 987 | /* For tracking memory events, indicate the entire frame has been |
| 988 | * allocated, but pretend that only the first four words are written */ |
| 989 | VG_TRACK( new_mem_stack_signal, (Addr)frame, sizeof(VgSigFrame) ); |
| 990 | |
sewardj | 2e93c50 | 2002-04-12 11:12:52 +0000 | [diff] [blame] | 991 | /* Assert that the frame is placed correctly. */ |
| 992 | vg_assert( (sizeof(VgSigFrame) & 0x3) == 0 ); |
| 993 | vg_assert( ((Char*)(&frame->magicE)) + sizeof(UInt) |
sewardj | 2342c97 | 2002-05-22 23:34:20 +0000 | [diff] [blame] | 994 | == ((Char*)(esp_top_of_frame)) ); |
sewardj | 2e93c50 | 2002-04-12 11:12:52 +0000 | [diff] [blame] | 995 | |
njn25 | e49d8e7 | 2002-09-23 09:36:25 +0000 | [diff] [blame] | 996 | /* retaddr, sigNo, psigInfo, puContext fields are to be written */ |
njn | 7271864 | 2003-07-24 08:45:32 +0000 | [diff] [blame] | 997 | VG_TRACK( pre_mem_write, Vg_CoreSignal, tid, "signal handler frame", |
jsgf | 855d93d | 2003-10-13 22:26:55 +0000 | [diff] [blame] | 998 | (Addr)frame, offsetof(VgSigFrame, handlerArgs) ); |
sewardj | 2e93c50 | 2002-04-12 11:12:52 +0000 | [diff] [blame] | 999 | frame->retaddr = (UInt)(&VG_(signalreturn_bogusRA)); |
| 1000 | frame->sigNo = sigNo; |
sewardj | f247eae | 2002-09-27 00:46:59 +0000 | [diff] [blame] | 1001 | frame->sigNo_private = sigNo; |
jsgf | 855d93d | 2003-10-13 22:26:55 +0000 | [diff] [blame] | 1002 | VG_TRACK( post_mem_write, (Addr)frame, offsetof(VgSigFrame, handlerArgs) ); |
| 1003 | |
| 1004 | if (vg_scss.scss_per_sig[sigNo].scss_flags & VKI_SA_SIGINFO) { |
| 1005 | /* if the client asked for a siginfo delivery, then build the stack that way */ |
| 1006 | VG_TRACK( pre_mem_write, Vg_CoreSignal, tid, "signal handler frame (siginfo)", |
| 1007 | (Addr)&frame->handlerArgs, sizeof(frame->handlerArgs.sigInfo) ); |
| 1008 | frame->handlerArgs.sigInfo.psigInfo = (Addr)&frame->sigInfo; |
| 1009 | frame->handlerArgs.sigInfo.puContext = (Addr)&frame->uContext; |
| 1010 | VG_TRACK( post_mem_write, (Addr)&frame->handlerArgs, sizeof(frame->handlerArgs.sigInfo) ); |
| 1011 | |
| 1012 | VG_TRACK( pre_mem_write, Vg_CoreSignal, tid, "signal handler frame (siginfo)", |
| 1013 | (Addr)&frame->sigInfo, sizeof(frame->sigInfo) ); |
| 1014 | VG_(memcpy)(&frame->sigInfo, siginfo, sizeof(vki_ksiginfo_t)); |
| 1015 | VG_TRACK( post_mem_write, (Addr)&frame->sigInfo, sizeof(frame->sigInfo) ); |
| 1016 | |
| 1017 | VG_TRACK( pre_mem_write, Vg_CoreSignal, tid, "signal handler frame (siginfo)", |
| 1018 | (Addr)&frame->uContext, sizeof(frame->uContext) ); |
| 1019 | synth_ucontext(tid, siginfo, &vg_scss.scss_per_sig[sigNo].scss_mask, &frame->uContext); |
| 1020 | VG_TRACK( post_mem_write, (Addr)&frame->uContext, sizeof(frame->uContext) ); |
| 1021 | } else { |
| 1022 | struct vki_ucontext uc; |
| 1023 | |
| 1024 | /* otherwise just put the sigcontext there */ |
| 1025 | |
| 1026 | synth_ucontext(tid, siginfo, &vg_scss.scss_per_sig[sigNo].scss_mask, &uc); |
| 1027 | |
| 1028 | VG_TRACK( pre_mem_write, Vg_CoreSignal, tid, "signal handler frame (sigcontext)", |
| 1029 | (Addr)&frame->handlerArgs, sizeof(frame->handlerArgs.sigContext) ); |
| 1030 | VG_(memcpy)(&frame->handlerArgs.sigContext, &uc.uc_mcontext, |
| 1031 | sizeof(struct vki_sigcontext)); |
| 1032 | VG_TRACK( post_mem_write, (Addr)&frame->handlerArgs, |
| 1033 | sizeof(frame->handlerArgs.sigContext) ); |
| 1034 | |
| 1035 | frame->handlerArgs.sigContext.oldmask = tst->sig_mask.ws[0]; |
| 1036 | } |
| 1037 | |
sewardj | 2e93c50 | 2002-04-12 11:12:52 +0000 | [diff] [blame] | 1038 | frame->magicPI = 0x31415927; |
| 1039 | |
sewardj | b91ae7f | 2003-04-29 23:50:00 +0000 | [diff] [blame] | 1040 | for (i = 0; i < VG_SIZE_OF_SSESTATE_W; i++) |
njn | d304045 | 2003-05-19 15:04:06 +0000 | [diff] [blame] | 1041 | frame->m_sse[i] = tst->m_sse[i]; |
sewardj | de4a1d0 | 2002-03-22 01:27:54 +0000 | [diff] [blame] | 1042 | |
njn | d304045 | 2003-05-19 15:04:06 +0000 | [diff] [blame] | 1043 | frame->m_eax = tst->m_eax; |
| 1044 | frame->m_ecx = tst->m_ecx; |
| 1045 | frame->m_edx = tst->m_edx; |
| 1046 | frame->m_ebx = tst->m_ebx; |
| 1047 | frame->m_ebp = tst->m_ebp; |
| 1048 | frame->m_esp = tst->m_esp; |
| 1049 | frame->m_esi = tst->m_esi; |
| 1050 | frame->m_edi = tst->m_edi; |
| 1051 | frame->m_eflags = tst->m_eflags; |
| 1052 | frame->m_eip = tst->m_eip; |
| 1053 | |
| 1054 | if (VG_(needs).shadow_regs) { |
| 1055 | frame->sh_eax = tst->sh_eax; |
| 1056 | frame->sh_ecx = tst->sh_ecx; |
| 1057 | frame->sh_edx = tst->sh_edx; |
| 1058 | frame->sh_ebx = tst->sh_ebx; |
| 1059 | frame->sh_ebp = tst->sh_ebp; |
| 1060 | frame->sh_esp = tst->sh_esp; |
| 1061 | frame->sh_esi = tst->sh_esi; |
| 1062 | frame->sh_edi = tst->sh_edi; |
| 1063 | frame->sh_eflags = tst->sh_eflags; |
| 1064 | } |
sewardj | de4a1d0 | 2002-03-22 01:27:54 +0000 | [diff] [blame] | 1065 | |
jsgf | 855d93d | 2003-10-13 22:26:55 +0000 | [diff] [blame] | 1066 | frame->mask = tst->sig_mask; |
| 1067 | |
| 1068 | /* If the thread is currently blocked in a syscall, we want it to |
| 1069 | resume as runnable. */ |
| 1070 | if (tst->status == VgTs_WaitSys) |
| 1071 | frame->status = VgTs_Runnable; |
| 1072 | else |
| 1073 | frame->status = tst->status; |
sewardj | de4a1d0 | 2002-03-22 01:27:54 +0000 | [diff] [blame] | 1074 | |
sewardj | 2e93c50 | 2002-04-12 11:12:52 +0000 | [diff] [blame] | 1075 | frame->magicE = 0x27182818; |
| 1076 | |
njn | d304045 | 2003-05-19 15:04:06 +0000 | [diff] [blame] | 1077 | /* Ensure 'tid' and 'tst' correspond */ |
| 1078 | vg_assert(& VG_(threads)[tid] == tst); |
sewardj | 2e93c50 | 2002-04-12 11:12:52 +0000 | [diff] [blame] | 1079 | /* Set the thread so it will next run the handler. */ |
njn | d304045 | 2003-05-19 15:04:06 +0000 | [diff] [blame] | 1080 | /* tst->m_esp = esp; */ |
| 1081 | SET_SIGNAL_ESP(tid, esp); |
| 1082 | |
sewardj | 018f762 | 2002-05-15 21:13:39 +0000 | [diff] [blame] | 1083 | tst->m_eip = (Addr)vg_scss.scss_per_sig[sigNo].scss_handler; |
sewardj | 2e93c50 | 2002-04-12 11:12:52 +0000 | [diff] [blame] | 1084 | /* This thread needs to be marked runnable, but we leave that the |
| 1085 | caller to do. */ |
sewardj | de4a1d0 | 2002-03-22 01:27:54 +0000 | [diff] [blame] | 1086 | |
jsgf | 855d93d | 2003-10-13 22:26:55 +0000 | [diff] [blame] | 1087 | if (0) |
| 1088 | VG_(printf)("pushed signal frame; %%ESP now = %p, next %%EBP = %p, status=%d\n", |
| 1089 | esp, tst->m_eip, tst->status); |
sewardj | de4a1d0 | 2002-03-22 01:27:54 +0000 | [diff] [blame] | 1090 | } |
| 1091 | |
sewardj | de4a1d0 | 2002-03-22 01:27:54 +0000 | [diff] [blame] | 1092 | /* Clear the signal frame created by vg_push_signal_frame, restore the |
| 1093 | simulated machine state, and return the signal number that the |
| 1094 | frame was for. */ |
| 1095 | static |
sewardj | 2e93c50 | 2002-04-12 11:12:52 +0000 | [diff] [blame] | 1096 | Int vg_pop_signal_frame ( ThreadId tid ) |
sewardj | de4a1d0 | 2002-03-22 01:27:54 +0000 | [diff] [blame] | 1097 | { |
sewardj | 2e93c50 | 2002-04-12 11:12:52 +0000 | [diff] [blame] | 1098 | Addr esp; |
sewardj | de4a1d0 | 2002-03-22 01:27:54 +0000 | [diff] [blame] | 1099 | Int sigNo, i; |
sewardj | 2e93c50 | 2002-04-12 11:12:52 +0000 | [diff] [blame] | 1100 | VgSigFrame* frame; |
| 1101 | ThreadState* tst; |
sewardj | de4a1d0 | 2002-03-22 01:27:54 +0000 | [diff] [blame] | 1102 | |
sewardj | 018f762 | 2002-05-15 21:13:39 +0000 | [diff] [blame] | 1103 | vg_assert(VG_(is_valid_tid)(tid)); |
| 1104 | tst = & VG_(threads)[tid]; |
sewardj | 2e93c50 | 2002-04-12 11:12:52 +0000 | [diff] [blame] | 1105 | |
sewardj | 54cacf0 | 2002-04-12 23:24:59 +0000 | [diff] [blame] | 1106 | /* Correctly reestablish the frame base address. */ |
sewardj | 2e93c50 | 2002-04-12 11:12:52 +0000 | [diff] [blame] | 1107 | esp = tst->m_esp; |
sewardj | 54cacf0 | 2002-04-12 23:24:59 +0000 | [diff] [blame] | 1108 | frame = (VgSigFrame*) |
| 1109 | (esp -4 /* because the handler's RET pops the RA */ |
| 1110 | +20 /* because signalreturn_bogusRA pushes 5 words */); |
sewardj | 2e93c50 | 2002-04-12 11:12:52 +0000 | [diff] [blame] | 1111 | |
| 1112 | vg_assert(frame->magicPI == 0x31415927); |
| 1113 | vg_assert(frame->magicE == 0x27182818); |
sewardj | de4a1d0 | 2002-03-22 01:27:54 +0000 | [diff] [blame] | 1114 | if (VG_(clo_trace_signals)) |
sewardj | b48e500 | 2002-05-13 00:16:03 +0000 | [diff] [blame] | 1115 | VG_(message)(Vg_DebugMsg, |
jsgf | 855d93d | 2003-10-13 22:26:55 +0000 | [diff] [blame] | 1116 | "vg_pop_signal_frame (thread %d): valid magic; EIP=%p", tid, frame->m_eip); |
sewardj | de4a1d0 | 2002-03-22 01:27:54 +0000 | [diff] [blame] | 1117 | |
sewardj | 2342c97 | 2002-05-22 23:34:20 +0000 | [diff] [blame] | 1118 | /* Mark the frame structure as nonaccessible. */ |
njn25 | e49d8e7 | 2002-09-23 09:36:25 +0000 | [diff] [blame] | 1119 | VG_TRACK( die_mem_stack_signal, (Addr)frame, sizeof(VgSigFrame) ); |
sewardj | de4a1d0 | 2002-03-22 01:27:54 +0000 | [diff] [blame] | 1120 | |
njn | d304045 | 2003-05-19 15:04:06 +0000 | [diff] [blame] | 1121 | /* restore machine state */ |
| 1122 | for (i = 0; i < VG_SIZE_OF_SSESTATE_W; i++) |
| 1123 | tst->m_sse[i] = frame->m_sse[i]; |
sewardj | f247eae | 2002-09-27 00:46:59 +0000 | [diff] [blame] | 1124 | |
njn | d304045 | 2003-05-19 15:04:06 +0000 | [diff] [blame] | 1125 | tst->m_eax = frame->m_eax; |
| 1126 | tst->m_ecx = frame->m_ecx; |
| 1127 | tst->m_edx = frame->m_edx; |
| 1128 | tst->m_ebx = frame->m_ebx; |
| 1129 | tst->m_ebp = frame->m_ebp; |
| 1130 | tst->m_esp = frame->m_esp; |
| 1131 | tst->m_esi = frame->m_esi; |
| 1132 | tst->m_edi = frame->m_edi; |
| 1133 | tst->m_eflags = frame->m_eflags; |
| 1134 | tst->m_eip = frame->m_eip; |
| 1135 | |
| 1136 | if (VG_(needs).shadow_regs) { |
| 1137 | tst->sh_eax = frame->sh_eax; |
| 1138 | tst->sh_ecx = frame->sh_ecx; |
| 1139 | tst->sh_edx = frame->sh_edx; |
| 1140 | tst->sh_ebx = frame->sh_ebx; |
| 1141 | tst->sh_ebp = frame->sh_ebp; |
| 1142 | tst->sh_esp = frame->sh_esp; |
| 1143 | tst->sh_esi = frame->sh_esi; |
| 1144 | tst->sh_edi = frame->sh_edi; |
| 1145 | tst->sh_eflags = frame->sh_eflags; |
| 1146 | } |
| 1147 | |
sewardj | f247eae | 2002-09-27 00:46:59 +0000 | [diff] [blame] | 1148 | /* don't use the copy exposed to the handler; it might have changed |
| 1149 | it. */ |
| 1150 | sigNo = frame->sigNo_private; |
sewardj | 2e93c50 | 2002-04-12 11:12:52 +0000 | [diff] [blame] | 1151 | |
| 1152 | /* And restore the thread's status to what it was before the signal |
| 1153 | was delivered. */ |
| 1154 | tst->status = frame->status; |
| 1155 | |
jsgf | 855d93d | 2003-10-13 22:26:55 +0000 | [diff] [blame] | 1156 | tst->sig_mask = frame->mask; |
| 1157 | VG_(proxy_setsigmask)(tid); |
| 1158 | |
njn | fdc28af | 2003-02-24 10:36:48 +0000 | [diff] [blame] | 1159 | /* Notify skins */ |
| 1160 | VG_TRACK( post_deliver_signal, tid, sigNo ); |
| 1161 | |
sewardj | de4a1d0 | 2002-03-22 01:27:54 +0000 | [diff] [blame] | 1162 | return sigNo; |
| 1163 | } |
| 1164 | |
| 1165 | |
| 1166 | /* A handler is returning. Restore the machine state from the stacked |
| 1167 | VgSigContext and continue with whatever was going on before the |
sewardj | 77e466c | 2002-04-14 02:29:29 +0000 | [diff] [blame] | 1168 | handler ran. Returns the SA_RESTART syscall-restartability-status |
| 1169 | of the delivered signal. */ |
sewardj | de4a1d0 | 2002-03-22 01:27:54 +0000 | [diff] [blame] | 1170 | |
sewardj | 77e466c | 2002-04-14 02:29:29 +0000 | [diff] [blame] | 1171 | Bool VG_(signal_returns) ( ThreadId tid ) |
sewardj | de4a1d0 | 2002-03-22 01:27:54 +0000 | [diff] [blame] | 1172 | { |
sewardj | 2e93c50 | 2002-04-12 11:12:52 +0000 | [diff] [blame] | 1173 | Int sigNo; |
sewardj | de4a1d0 | 2002-03-22 01:27:54 +0000 | [diff] [blame] | 1174 | |
sewardj | 2e93c50 | 2002-04-12 11:12:52 +0000 | [diff] [blame] | 1175 | /* Pop the signal frame and restore tid's status to what it was |
| 1176 | before the signal was delivered. */ |
| 1177 | sigNo = vg_pop_signal_frame(tid); |
sewardj | de4a1d0 | 2002-03-22 01:27:54 +0000 | [diff] [blame] | 1178 | |
sewardj | b48e500 | 2002-05-13 00:16:03 +0000 | [diff] [blame] | 1179 | vg_assert(sigNo >= 1 && sigNo <= VKI_KNSIG); |
sewardj | de4a1d0 | 2002-03-22 01:27:54 +0000 | [diff] [blame] | 1180 | |
sewardj | 77e466c | 2002-04-14 02:29:29 +0000 | [diff] [blame] | 1181 | /* Scheduler now can resume this thread, or perhaps some other. |
| 1182 | Tell the scheduler whether or not any syscall interrupted by |
jsgf | 855d93d | 2003-10-13 22:26:55 +0000 | [diff] [blame] | 1183 | this signal should be restarted, if possible, or no. This is |
| 1184 | only used for nanosleep; all other blocking syscalls are handled |
| 1185 | in VG_(deliver_signal)(). |
| 1186 | */ |
sewardj | 018f762 | 2002-05-15 21:13:39 +0000 | [diff] [blame] | 1187 | return |
| 1188 | (vg_scss.scss_per_sig[sigNo].scss_flags & VKI_SA_RESTART) |
| 1189 | ? True |
| 1190 | : False; |
sewardj | de4a1d0 | 2002-03-22 01:27:54 +0000 | [diff] [blame] | 1191 | } |
| 1192 | |
jsgf | 855d93d | 2003-10-13 22:26:55 +0000 | [diff] [blame] | 1193 | static const Char *signame(Int sigNo) |
sewardj | de4a1d0 | 2002-03-22 01:27:54 +0000 | [diff] [blame] | 1194 | { |
jsgf | 855d93d | 2003-10-13 22:26:55 +0000 | [diff] [blame] | 1195 | static Char buf[10]; |
sewardj | b48e500 | 2002-05-13 00:16:03 +0000 | [diff] [blame] | 1196 | |
jsgf | 855d93d | 2003-10-13 22:26:55 +0000 | [diff] [blame] | 1197 | switch(sigNo) { |
| 1198 | #define S(x) case VKI_##x: return #x |
| 1199 | S(SIGHUP); |
| 1200 | S(SIGINT); |
| 1201 | S(SIGQUIT); |
| 1202 | S(SIGILL); |
| 1203 | S(SIGTRAP); |
| 1204 | S(SIGABRT); |
| 1205 | S(SIGBUS); |
| 1206 | S(SIGFPE); |
| 1207 | S(SIGKILL); |
| 1208 | S(SIGUSR1); |
| 1209 | S(SIGUSR2); |
| 1210 | S(SIGSEGV); |
| 1211 | S(SIGPIPE); |
| 1212 | S(SIGALRM); |
| 1213 | S(SIGTERM); |
| 1214 | S(SIGSTKFLT); |
| 1215 | S(SIGCHLD); |
| 1216 | S(SIGCONT); |
| 1217 | S(SIGSTOP); |
| 1218 | S(SIGTSTP); |
| 1219 | S(SIGTTIN); |
| 1220 | S(SIGTTOU); |
| 1221 | S(SIGURG); |
| 1222 | S(SIGXCPU); |
| 1223 | S(SIGXFSZ); |
| 1224 | S(SIGVTALRM); |
| 1225 | S(SIGPROF); |
| 1226 | S(SIGWINCH); |
| 1227 | S(SIGIO); |
| 1228 | S(SIGPWR); |
| 1229 | S(SIGUNUSED); |
| 1230 | #undef S |
sewardj | de4a1d0 | 2002-03-22 01:27:54 +0000 | [diff] [blame] | 1231 | |
jsgf | 855d93d | 2003-10-13 22:26:55 +0000 | [diff] [blame] | 1232 | case VKI_SIGRTMIN ... VKI_SIGRTMAX: |
| 1233 | VG_(sprintf)(buf, "SIGRT%d", sigNo); |
| 1234 | return buf; |
sewardj | de4a1d0 | 2002-03-22 01:27:54 +0000 | [diff] [blame] | 1235 | |
jsgf | 855d93d | 2003-10-13 22:26:55 +0000 | [diff] [blame] | 1236 | default: |
| 1237 | VG_(sprintf)(buf, "SIG%d", sigNo); |
| 1238 | return buf; |
| 1239 | } |
| 1240 | } |
sewardj | de4a1d0 | 2002-03-22 01:27:54 +0000 | [diff] [blame] | 1241 | |
jsgf | 855d93d | 2003-10-13 22:26:55 +0000 | [diff] [blame] | 1242 | /* Hit ourselves with a signal using the default handler */ |
| 1243 | void VG_(kill_self)(Int sigNo) |
| 1244 | { |
| 1245 | vki_ksigset_t mask, origmask; |
| 1246 | vki_ksigaction sa, origsa; |
sewardj | 018f762 | 2002-05-15 21:13:39 +0000 | [diff] [blame] | 1247 | |
jsgf | 855d93d | 2003-10-13 22:26:55 +0000 | [diff] [blame] | 1248 | sa.ksa_handler = VKI_SIG_DFL; |
| 1249 | sa.ksa_flags = 0; |
| 1250 | sa.ksa_restorer = 0; |
| 1251 | VG_(ksigemptyset)(&sa.ksa_mask); |
sewardj | 2e93c50 | 2002-04-12 11:12:52 +0000 | [diff] [blame] | 1252 | |
jsgf | 855d93d | 2003-10-13 22:26:55 +0000 | [diff] [blame] | 1253 | VG_(ksigaction)(sigNo, &sa, &origsa); |
sewardj | 018f762 | 2002-05-15 21:13:39 +0000 | [diff] [blame] | 1254 | |
jsgf | 855d93d | 2003-10-13 22:26:55 +0000 | [diff] [blame] | 1255 | VG_(ksigfillset)(&mask); |
| 1256 | VG_(ksigdelset)(&mask, sigNo); |
| 1257 | VG_(ksigprocmask)(VKI_SIG_SETMASK, &mask, &origmask); |
| 1258 | |
| 1259 | VG_(ktkill)(VG_(getpid)(), sigNo); |
| 1260 | |
| 1261 | VG_(ksigaction)(sigNo, &origsa, NULL); |
| 1262 | VG_(ksigprocmask)(VKI_SIG_SETMASK, &origmask, NULL); |
| 1263 | } |
| 1264 | |
| 1265 | /* |
| 1266 | Perform the default action of a signal. Returns if the default |
| 1267 | action isn't fatal. |
| 1268 | |
| 1269 | If we're not being quiet, then print out some more detail about |
| 1270 | fatal signals (esp. core dumping signals). |
| 1271 | */ |
| 1272 | static void vg_default_action(const vki_ksiginfo_t *info, ThreadId tid) |
| 1273 | { |
| 1274 | Int sigNo = info->si_signo; |
| 1275 | Bool terminate = False; |
| 1276 | Bool core = False; |
| 1277 | |
| 1278 | switch(sigNo) { |
| 1279 | case VKI_SIGQUIT: /* core */ |
| 1280 | case VKI_SIGILL: /* core */ |
| 1281 | case VKI_SIGABRT: /* core */ |
| 1282 | case VKI_SIGFPE: /* core */ |
| 1283 | case VKI_SIGSEGV: /* core */ |
| 1284 | case VKI_SIGBUS: /* core */ |
| 1285 | case VKI_SIGTRAP: /* core */ |
| 1286 | case VKI_SIGXCPU: /* core */ |
| 1287 | case VKI_SIGXFSZ: /* core */ |
| 1288 | terminate = True; |
| 1289 | core = True; |
| 1290 | break; |
| 1291 | |
| 1292 | case VKI_SIGHUP: /* term */ |
| 1293 | case VKI_SIGINT: /* term */ |
| 1294 | case VKI_SIGKILL: /* term - we won't see this */ |
| 1295 | case VKI_SIGPIPE: /* term */ |
| 1296 | case VKI_SIGALRM: /* term */ |
| 1297 | case VKI_SIGTERM: /* term */ |
| 1298 | case VKI_SIGUSR1: /* term */ |
| 1299 | case VKI_SIGUSR2: /* term */ |
| 1300 | case VKI_SIGIO: /* term */ |
| 1301 | case VKI_SIGPWR: /* term */ |
| 1302 | case VKI_SIGSYS: /* term */ |
| 1303 | case VKI_SIGPROF: /* term */ |
| 1304 | case VKI_SIGVTALRM: /* term */ |
| 1305 | case VKI_SIGRTMIN ... VKI_SIGRTMAX: /* term */ |
| 1306 | terminate = True; |
| 1307 | break; |
| 1308 | } |
| 1309 | |
| 1310 | vg_assert(!core || (core && terminate)); |
| 1311 | |
| 1312 | if (terminate) { |
| 1313 | if (VG_(clo_verbosity) != 0 && (core || VG_(clo_verbosity) > 1)) { |
| 1314 | VG_(message)(Vg_UserMsg, ""); |
| 1315 | VG_(message)(Vg_UserMsg, "Process terminating with default action of signal %d (%s)%s", |
| 1316 | sigNo, signame(sigNo), core ? ": dumping core" : ""); |
| 1317 | |
| 1318 | /* Be helpful - decode some more details about this fault */ |
| 1319 | if (info->si_code > VKI_SI_USER) { |
| 1320 | const Char *event = NULL; |
| 1321 | |
| 1322 | switch(sigNo) { |
| 1323 | case VKI_SIGSEGV: |
| 1324 | switch(info->si_code) { |
nethercote | 3b390c7 | 2003-11-13 17:53:43 +0000 | [diff] [blame^] | 1325 | case 1: event = "Address not mapped to object"; break; |
| 1326 | case 2: event = "Invalid permissions for mapped object"; break; |
jsgf | 855d93d | 2003-10-13 22:26:55 +0000 | [diff] [blame] | 1327 | } |
| 1328 | break; |
| 1329 | |
| 1330 | case VKI_SIGILL: |
| 1331 | switch(info->si_code) { |
nethercote | 3b390c7 | 2003-11-13 17:53:43 +0000 | [diff] [blame^] | 1332 | case 1: event = "Illegal opcode"; break; |
| 1333 | case 2: event = "Illegal operand"; break; |
| 1334 | case 3: event = "Illegal addressing mode"; break; |
| 1335 | case 4: event = "Illegal trap"; break; |
| 1336 | case 5: event = "Privileged opcode"; break; |
| 1337 | case 6: event = "Privileged register"; break; |
| 1338 | case 7: event = "Coprocessor error"; break; |
| 1339 | case 8: event = "Internal stack error"; break; |
jsgf | 855d93d | 2003-10-13 22:26:55 +0000 | [diff] [blame] | 1340 | } |
| 1341 | break; |
| 1342 | |
| 1343 | case VKI_SIGFPE: |
| 1344 | switch (info->si_code) { |
nethercote | 3b390c7 | 2003-11-13 17:53:43 +0000 | [diff] [blame^] | 1345 | case 1: event = "Integer divide by zero"; break; |
| 1346 | case 2: event = "Integer overflow"; break; |
jsgf | 855d93d | 2003-10-13 22:26:55 +0000 | [diff] [blame] | 1347 | case 3: event = "FP divide by zero"; break; |
| 1348 | case 4: event = "FP overflow"; break; |
| 1349 | case 5: event = "FP underflow"; break; |
| 1350 | case 6: event = "FP inexact"; break; |
| 1351 | case 7: event = "FP invalid operation"; break; |
| 1352 | case 8: event = "FP subscript out of range"; break; |
| 1353 | } |
| 1354 | break; |
| 1355 | |
| 1356 | case VKI_SIGBUS: |
| 1357 | switch (info->si_code) { |
nethercote | 3b390c7 | 2003-11-13 17:53:43 +0000 | [diff] [blame^] | 1358 | case 1: event = "Invalid address alignment"; break; |
| 1359 | case 2: event = "Non-existent physical address"; break; |
| 1360 | case 3: event = "Hardware error"; break; |
jsgf | 855d93d | 2003-10-13 22:26:55 +0000 | [diff] [blame] | 1361 | } |
| 1362 | break; |
| 1363 | } |
| 1364 | |
| 1365 | if (event != NULL) |
nethercote | 3b390c7 | 2003-11-13 17:53:43 +0000 | [diff] [blame^] | 1366 | VG_(message)(Vg_UserMsg, " %s at address %p", |
jsgf | 855d93d | 2003-10-13 22:26:55 +0000 | [diff] [blame] | 1367 | event, info->_sifields._sigfault._addr); |
| 1368 | } |
| 1369 | |
| 1370 | if (tid != VG_INVALID_THREADID) { |
| 1371 | ExeContext *ec = VG_(get_ExeContext)(tid); |
| 1372 | VG_(pp_ExeContext)(ec); |
| 1373 | } |
| 1374 | } |
| 1375 | |
| 1376 | if (VG_(fatal_signal_set)) { |
| 1377 | VG_(fatal_sigNo) = sigNo; |
| 1378 | __builtin_longjmp(VG_(fatal_signal_jmpbuf), 1); |
sewardj | 018f762 | 2002-05-15 21:13:39 +0000 | [diff] [blame] | 1379 | } |
sewardj | de4a1d0 | 2002-03-22 01:27:54 +0000 | [diff] [blame] | 1380 | } |
| 1381 | |
jsgf | 855d93d | 2003-10-13 22:26:55 +0000 | [diff] [blame] | 1382 | VG_(kill_self)(sigNo); |
sewardj | 018f762 | 2002-05-15 21:13:39 +0000 | [diff] [blame] | 1383 | |
jsgf | 855d93d | 2003-10-13 22:26:55 +0000 | [diff] [blame] | 1384 | vg_assert(!terminate); |
sewardj | b48e500 | 2002-05-13 00:16:03 +0000 | [diff] [blame] | 1385 | } |
| 1386 | |
| 1387 | |
jsgf | 855d93d | 2003-10-13 22:26:55 +0000 | [diff] [blame] | 1388 | void VG_(deliver_signal) ( ThreadId tid, const vki_ksiginfo_t *info, Bool async ) |
sewardj | de4a1d0 | 2002-03-22 01:27:54 +0000 | [diff] [blame] | 1389 | { |
jsgf | 855d93d | 2003-10-13 22:26:55 +0000 | [diff] [blame] | 1390 | Int sigNo = info->si_signo; |
| 1391 | vki_ksigset_t handlermask; |
jsgf | 855d93d | 2003-10-13 22:26:55 +0000 | [diff] [blame] | 1392 | SCSS_Per_Signal *handler = &vg_scss.scss_per_sig[sigNo]; |
| 1393 | ThreadState *tst = VG_(get_ThreadState)(tid); |
| 1394 | |
| 1395 | if (VG_(clo_trace_signals)) |
| 1396 | VG_(message)(Vg_DebugMsg,"delivering signal %d (%s) to thread %d", |
| 1397 | sigNo, signame(sigNo), tid ); |
| 1398 | |
| 1399 | if (sigNo == VKI_SIGVGINT) { |
| 1400 | /* If this is a SIGVGINT, then we just ACK the signal and carry |
| 1401 | on; the application need never know about it (except for any |
| 1402 | effect on its syscalls). */ |
| 1403 | vg_assert(async); |
| 1404 | |
| 1405 | if (tst->status == VgTs_WaitSys) { |
| 1406 | /* blocked in a syscall; we assume it should be interrupted */ |
| 1407 | if (tst->m_eax == -VKI_ERESTARTSYS) |
| 1408 | tst->m_eax = -VKI_EINTR; |
| 1409 | } |
| 1410 | |
| 1411 | VG_(proxy_sigack)(tid, &tst->sig_mask); |
| 1412 | return; |
| 1413 | } |
| 1414 | |
| 1415 | /* If thread is currently blocked in a syscall, then resume as |
| 1416 | runnable. If the syscall needs restarting, tweak the machine |
| 1417 | state to make it happen. */ |
| 1418 | if (tst->status == VgTs_WaitSys) { |
| 1419 | vg_assert(tst->syscallno != -1); |
| 1420 | |
fitzhardinge | a09a1b5 | 2003-11-07 23:09:48 +0000 | [diff] [blame] | 1421 | /* OK, the thread was waiting for a syscall to complete. This |
| 1422 | means that the proxy has either not yet processed the |
| 1423 | RunSyscall request, or was processing it when the signal |
| 1424 | came. Either way, it is going to give us some syscall |
| 1425 | results right now, so wait for them to appear. This makes |
| 1426 | the thread runnable again, so we're in the right state to run |
| 1427 | the handler, and resume the syscall when we're done. */ |
| 1428 | VG_(proxy_wait_sys)(tid); |
| 1429 | |
jsgf | 855d93d | 2003-10-13 22:26:55 +0000 | [diff] [blame] | 1430 | if (0) |
| 1431 | VG_(printf)("signal %d interrupting syscall %d\n", |
| 1432 | sigNo, tst->syscallno); |
| 1433 | |
| 1434 | if (tst->m_eax == -VKI_ERESTARTSYS) { |
| 1435 | if (handler->scss_flags & VKI_SA_RESTART) { |
fitzhardinge | e1c06d8 | 2003-10-30 07:21:44 +0000 | [diff] [blame] | 1436 | VG_(restart_syscall)(tid); |
jsgf | 855d93d | 2003-10-13 22:26:55 +0000 | [diff] [blame] | 1437 | } else |
| 1438 | tst->m_eax = -VKI_EINTR; |
| 1439 | } else { |
| 1440 | /* return value is already in eax - either EINTR or the |
| 1441 | normal return value */ |
| 1442 | } |
| 1443 | } |
| 1444 | |
| 1445 | vg_assert(handler->scss_handler != VKI_SIG_IGN); |
| 1446 | |
| 1447 | if (sigNo == VKI_SIGCHLD && (handler->scss_flags & VKI_SA_NOCLDWAIT)) { |
| 1448 | //VG_(printf)("sigNo==SIGCHLD and app asked for NOCLDWAIT\n"); |
| 1449 | vg_babyeater(sigNo, NULL, NULL); |
| 1450 | } |
| 1451 | |
| 1452 | if (handler->scss_handler == VKI_SIG_DFL) { |
| 1453 | handlermask = tst->sig_mask; /* no change to signal mask */ |
| 1454 | vg_default_action(info, tid); |
| 1455 | } else { |
| 1456 | /* Create a signal delivery frame, and set the client's %ESP and |
| 1457 | %EIP so that when execution continues, we will enter the |
| 1458 | signal handler with the frame on top of the client's stack, |
| 1459 | as it expects. */ |
| 1460 | vg_assert(VG_(is_valid_tid)(tid)); |
| 1461 | vg_push_signal_frame ( tid, info ); |
| 1462 | |
| 1463 | if (handler->scss_flags & VKI_SA_ONESHOT) { |
| 1464 | /* Do the ONESHOT thing. */ |
| 1465 | handler->scss_handler = VKI_SIG_DFL; |
| 1466 | |
| 1467 | VG_(handle_SCSS_change)( False /* lazy update */ ); |
| 1468 | } |
| 1469 | |
fitzhardinge | a09a1b5 | 2003-11-07 23:09:48 +0000 | [diff] [blame] | 1470 | switch(tst->status) { |
jsgf | 855d93d | 2003-10-13 22:26:55 +0000 | [diff] [blame] | 1471 | case VgTs_Runnable: |
| 1472 | break; |
| 1473 | |
| 1474 | case VgTs_WaitSys: |
jsgf | 855d93d | 2003-10-13 22:26:55 +0000 | [diff] [blame] | 1475 | case VgTs_WaitJoiner: |
| 1476 | case VgTs_WaitJoinee: |
| 1477 | case VgTs_WaitMX: |
| 1478 | case VgTs_WaitCV: |
| 1479 | case VgTs_Sleeping: |
fitzhardinge | a09a1b5 | 2003-11-07 23:09:48 +0000 | [diff] [blame] | 1480 | tst->status = VgTs_Runnable; |
jsgf | 855d93d | 2003-10-13 22:26:55 +0000 | [diff] [blame] | 1481 | break; |
| 1482 | |
| 1483 | case VgTs_Empty: |
| 1484 | VG_(core_panic)("unexpected thread state"); |
| 1485 | break; |
| 1486 | } |
| 1487 | |
jsgf | 855d93d | 2003-10-13 22:26:55 +0000 | [diff] [blame] | 1488 | /* handler gets the union of the signal's mask and the thread's |
| 1489 | mask */ |
| 1490 | handlermask = handler->scss_mask; |
| 1491 | VG_(ksigaddset_from_set)(&handlermask, &VG_(threads)[tid].sig_mask); |
| 1492 | |
| 1493 | /* also mask this signal, unless they ask us not to */ |
| 1494 | if (!(handler->scss_flags & VKI_SA_NOMASK)) |
| 1495 | VG_(ksigaddset)(&handlermask, sigNo); |
| 1496 | } |
| 1497 | |
| 1498 | /* tell proxy we're about to start running the handler */ |
| 1499 | if (async) |
| 1500 | VG_(proxy_sigack)(tid, &handlermask); |
| 1501 | } |
| 1502 | |
| 1503 | |
| 1504 | /* |
| 1505 | If the client set the handler for SIGCHLD to SIG_IGN, then we need |
| 1506 | to automatically dezombie any dead children. Also used if the |
| 1507 | client set the SA_NOCLDWAIT on their SIGCHLD handler. |
| 1508 | */ |
| 1509 | static |
| 1510 | void vg_babyeater ( Int sigNo, vki_ksiginfo_t *info, struct vki_ucontext *uc ) |
| 1511 | { |
| 1512 | Int status; |
| 1513 | Int pid; |
| 1514 | |
| 1515 | vg_assert(sigNo == VKI_SIGCHLD); |
| 1516 | |
| 1517 | while((pid = VG_(waitpid)(-1, &status, VKI_WNOHANG)) > 0) { |
| 1518 | if (VG_(clo_trace_signals)) |
| 1519 | VG_(message)(Vg_DebugMsg, "babyeater reaped %d", pid); |
| 1520 | } |
| 1521 | } |
| 1522 | |
| 1523 | /* |
| 1524 | Receive an async signal from the host. |
| 1525 | |
| 1526 | It being called in the context of a proxy LWP, and therefore is an |
| 1527 | async signal aimed at one of our threads. In this case, we pass |
| 1528 | the signal info to the main thread with VG_(proxy_handlesig)(). |
| 1529 | |
| 1530 | This should *never* be in the context of the main LWP, because |
| 1531 | all signals for which this is the handler should be blocked there. |
| 1532 | */ |
| 1533 | static |
| 1534 | void vg_async_signalhandler ( Int sigNo, vki_ksiginfo_t *info, struct vki_ucontext *uc ) |
| 1535 | { |
| 1536 | if (VG_(gettid)() == VG_(main_pid)) { |
| 1537 | VG_(printf)("got signal %d in LWP %d (%d)\n", |
| 1538 | sigNo, VG_(gettid)(), VG_(gettid)(), VG_(main_pid)); |
| 1539 | vg_assert(VG_(ksigismember)(&uc->uc_sigmask, sigNo)); |
| 1540 | } |
| 1541 | |
| 1542 | vg_assert(VG_(gettid)() != VG_(main_pid)); |
| 1543 | |
| 1544 | VG_(proxy_handlesig)(info, &uc->uc_mcontext); |
| 1545 | } |
| 1546 | |
| 1547 | /* |
| 1548 | Recieve a sync signal from the host. |
| 1549 | |
| 1550 | This should always be called from the main thread, though it may be |
| 1551 | called in a proxy LWP if someone sends an async version of one of |
| 1552 | the sync signals. |
| 1553 | */ |
| 1554 | static |
| 1555 | void vg_sync_signalhandler ( Int sigNo, vki_ksiginfo_t *info, struct vki_ucontext *uc ) |
| 1556 | { |
sewardj | 2e93c50 | 2002-04-12 11:12:52 +0000 | [diff] [blame] | 1557 | Int dummy_local; |
jsgf | 855d93d | 2003-10-13 22:26:55 +0000 | [diff] [blame] | 1558 | |
| 1559 | vg_assert(info != NULL); |
| 1560 | vg_assert(info->si_signo == sigNo); |
| 1561 | vg_assert(sigNo == VKI_SIGSEGV || |
| 1562 | sigNo == VKI_SIGBUS || |
| 1563 | sigNo == VKI_SIGFPE || |
| 1564 | sigNo == VKI_SIGILL); |
| 1565 | |
| 1566 | if (VG_(gettid)() != VG_(main_pid)) { |
| 1567 | /* We were sent one of our sync signals in an async way (or the |
| 1568 | proxy LWP code has a bug) */ |
| 1569 | vg_assert(info->si_code <= VKI_SI_USER); |
| 1570 | |
| 1571 | VG_(proxy_handlesig)(info, &uc->uc_mcontext); |
| 1572 | return; |
| 1573 | } |
| 1574 | |
sewardj | de4a1d0 | 2002-03-22 01:27:54 +0000 | [diff] [blame] | 1575 | |
sewardj | 7a61d91 | 2002-04-25 01:27:35 +0000 | [diff] [blame] | 1576 | /* |
| 1577 | if (sigNo == VKI_SIGUSR1) { |
| 1578 | VG_(printf)("YOWZA! SIGUSR1\n\n"); |
| 1579 | VG_(clo_trace_pthread_level) = 2; |
| 1580 | VG_(clo_trace_sched) = True; |
| 1581 | VG_(clo_trace_syscalls) = True; |
| 1582 | VG_(clo_trace_signals) = True; |
| 1583 | return; |
| 1584 | } |
| 1585 | */ |
| 1586 | |
sewardj | de4a1d0 | 2002-03-22 01:27:54 +0000 | [diff] [blame] | 1587 | if (VG_(clo_trace_signals)) { |
| 1588 | VG_(start_msg)(Vg_DebugMsg); |
| 1589 | VG_(add_to_msg)("signal %d arrived ... ", sigNo ); |
| 1590 | } |
sewardj | b48e500 | 2002-05-13 00:16:03 +0000 | [diff] [blame] | 1591 | vg_assert(sigNo >= 1 && sigNo <= VKI_KNSIG); |
sewardj | de4a1d0 | 2002-03-22 01:27:54 +0000 | [diff] [blame] | 1592 | |
| 1593 | /* Sanity check. Ensure we're really running on the signal stack |
| 1594 | we asked for. */ |
njn | 6eba4ef | 2003-05-01 08:06:41 +0000 | [diff] [blame] | 1595 | if (!( |
| 1596 | ((Char*)(&(VG_(sigstack)[0])) <= (Char*)(&dummy_local)) |
| 1597 | && |
| 1598 | ((Char*)(&dummy_local) < (Char*)(&(VG_(sigstack)[VG_SIGSTACK_SIZE_W]))) |
sewardj | de4a1d0 | 2002-03-22 01:27:54 +0000 | [diff] [blame] | 1599 | ) |
njn | 6eba4ef | 2003-05-01 08:06:41 +0000 | [diff] [blame] | 1600 | ) { |
sewardj | 2e93c50 | 2002-04-12 11:12:52 +0000 | [diff] [blame] | 1601 | VG_(message)(Vg_DebugMsg, |
| 1602 | "FATAL: signal delivered on the wrong stack?!"); |
| 1603 | VG_(message)(Vg_DebugMsg, |
| 1604 | "A possible workaround follows. Please tell me"); |
| 1605 | VG_(message)(Vg_DebugMsg, |
| 1606 | "(jseward@acm.org) if the suggested workaround doesn't help."); |
sewardj | de4a1d0 | 2002-03-22 01:27:54 +0000 | [diff] [blame] | 1607 | VG_(unimplemented) |
sewardj | 2e93c50 | 2002-04-12 11:12:52 +0000 | [diff] [blame] | 1608 | ("support for progs compiled with -p/-pg; " |
| 1609 | "rebuild your prog without -p/-pg"); |
sewardj | de4a1d0 | 2002-03-22 01:27:54 +0000 | [diff] [blame] | 1610 | } |
| 1611 | |
sewardj | 2e93c50 | 2002-04-12 11:12:52 +0000 | [diff] [blame] | 1612 | vg_assert((Char*)(&(VG_(sigstack)[0])) <= (Char*)(&dummy_local)); |
njn | 6eba4ef | 2003-05-01 08:06:41 +0000 | [diff] [blame] | 1613 | vg_assert((Char*)(&dummy_local) < (Char*)(&(VG_(sigstack)[VG_SIGSTACK_SIZE_W]))); |
sewardj | de4a1d0 | 2002-03-22 01:27:54 +0000 | [diff] [blame] | 1614 | |
jsgf | 855d93d | 2003-10-13 22:26:55 +0000 | [diff] [blame] | 1615 | if (VG_(scheduler_jmpbuf_valid)) { |
sewardj | 2e93c50 | 2002-04-12 11:12:52 +0000 | [diff] [blame] | 1616 | /* Can't continue; must longjmp back to the scheduler and thus |
| 1617 | enter the sighandler immediately. */ |
jsgf | 855d93d | 2003-10-13 22:26:55 +0000 | [diff] [blame] | 1618 | VG_(memcpy)(&VG_(unresumable_siginfo), info, sizeof(vki_ksiginfo_t)); |
| 1619 | |
sewardj | de4a1d0 | 2002-03-22 01:27:54 +0000 | [diff] [blame] | 1620 | VG_(longjmpd_on_signal) = sigNo; |
sewardj | 2e93c50 | 2002-04-12 11:12:52 +0000 | [diff] [blame] | 1621 | __builtin_longjmp(VG_(scheduler_jmpbuf),1); |
sewardj | de4a1d0 | 2002-03-22 01:27:54 +0000 | [diff] [blame] | 1622 | } |
sewardj | 872051c | 2002-07-13 12:12:56 +0000 | [diff] [blame] | 1623 | |
jsgf | 855d93d | 2003-10-13 22:26:55 +0000 | [diff] [blame] | 1624 | if (info->si_code <= VKI_SI_USER) { |
| 1625 | /* |
| 1626 | OK, one of sync signals was sent from user-mode, so try to |
fitzhardinge | e1c06d8 | 2003-10-30 07:21:44 +0000 | [diff] [blame] | 1627 | deliver it to someone who cares. Just add it to the |
| 1628 | process-wide pending signal set - signal routing will deliver |
| 1629 | it to someone eventually. |
jsgf | 855d93d | 2003-10-13 22:26:55 +0000 | [diff] [blame] | 1630 | |
fitzhardinge | e1c06d8 | 2003-10-30 07:21:44 +0000 | [diff] [blame] | 1631 | The only other place which touches proc_pending is |
| 1632 | VG_(route_signals), and it has signals blocked while doing |
| 1633 | so, so there's no race. |
| 1634 | */ |
| 1635 | VG_(message)(Vg_DebugMsg, |
| 1636 | "adding signal %d to pending set", sigNo); |
| 1637 | VG_(ksigaddset)(&proc_pending, sigNo); |
jsgf | 855d93d | 2003-10-13 22:26:55 +0000 | [diff] [blame] | 1638 | } else { |
| 1639 | /* |
| 1640 | A bad signal came from the kernel (indicating an instruction |
| 1641 | generated it), but there was no jumpbuf set up. This means |
| 1642 | it was actually generated by Valgrind internally. |
| 1643 | */ |
| 1644 | struct vki_sigcontext *sc = &uc->uc_mcontext; |
| 1645 | |
| 1646 | VG_(message)(Vg_DebugMsg, |
| 1647 | "INTERNAL ERROR: Valgrind received a signal %d (%s) - exiting", |
| 1648 | sigNo, signame(sigNo)); |
| 1649 | VG_(message)(Vg_DebugMsg, |
| 1650 | "si_code=%x Fault EIP: %p; Faulting address: %p", |
| 1651 | info->si_code, sc->eip, info->_sifields._sigfault._addr); |
| 1652 | |
| 1653 | if (0) |
| 1654 | VG_(kill_self)(sigNo); /* generate a core dump */ |
| 1655 | VG_(core_panic)("Killed by fatal signal"); |
| 1656 | } |
| 1657 | } |
| 1658 | |
| 1659 | |
| 1660 | /* |
| 1661 | This signal handler exists only so that the scheduler thread can |
| 1662 | poke the LWP to make it fall out of whatever syscall it is in. |
| 1663 | Used for thread termination and cancellation. |
| 1664 | */ |
| 1665 | static void proxy_sigvg_handler(int signo, vki_ksiginfo_t *si, struct vki_ucontext *uc) |
| 1666 | { |
| 1667 | vg_assert(signo == VKI_SIGVGINT || signo == VKI_SIGVGKILL); |
| 1668 | vg_assert(si->si_signo == signo); |
| 1669 | |
| 1670 | /* only pay attention to it if it came from the scheduler */ |
| 1671 | if (si->si_code == VKI_SI_TKILL && |
| 1672 | si->_sifields._kill._pid == VG_(main_pid)) { |
| 1673 | vg_assert(si->si_code == VKI_SI_TKILL); |
| 1674 | vg_assert(si->_sifields._kill._pid == VG_(main_pid)); |
| 1675 | |
| 1676 | VG_(proxy_handlesig)(si, &uc->uc_mcontext); |
sewardj | 872051c | 2002-07-13 12:12:56 +0000 | [diff] [blame] | 1677 | } |
sewardj | de4a1d0 | 2002-03-22 01:27:54 +0000 | [diff] [blame] | 1678 | } |
| 1679 | |
| 1680 | |
| 1681 | /* The outer insn loop calls here to reenable a host signal if |
| 1682 | vg_oursighandler longjmp'd. |
| 1683 | */ |
| 1684 | void VG_(unblock_host_signal) ( Int sigNo ) |
| 1685 | { |
jsgf | 855d93d | 2003-10-13 22:26:55 +0000 | [diff] [blame] | 1686 | vg_assert(sigNo == VKI_SIGSEGV || |
| 1687 | sigNo == VKI_SIGBUS || |
| 1688 | sigNo == VKI_SIGILL || |
| 1689 | sigNo == VKI_SIGFPE); |
| 1690 | set_main_sigmask(); |
sewardj | de4a1d0 | 2002-03-22 01:27:54 +0000 | [diff] [blame] | 1691 | } |
| 1692 | |
| 1693 | |
| 1694 | static __attribute((unused)) |
| 1695 | void pp_vg_ksigaction ( vki_ksigaction* sa ) |
| 1696 | { |
| 1697 | Int i; |
| 1698 | VG_(printf)("vg_ksigaction: handler %p, flags 0x%x, restorer %p\n", |
sewardj | 9a199dc | 2002-04-14 13:01:38 +0000 | [diff] [blame] | 1699 | sa->ksa_handler, (UInt)sa->ksa_flags, sa->ksa_restorer); |
sewardj | de4a1d0 | 2002-03-22 01:27:54 +0000 | [diff] [blame] | 1700 | VG_(printf)("vg_ksigaction: { "); |
sewardj | b48e500 | 2002-05-13 00:16:03 +0000 | [diff] [blame] | 1701 | for (i = 1; i <= VKI_KNSIG; i++) |
sewardj | de4a1d0 | 2002-03-22 01:27:54 +0000 | [diff] [blame] | 1702 | if (VG_(ksigismember(&(sa->ksa_mask),i))) |
| 1703 | VG_(printf)("%d ", i); |
| 1704 | VG_(printf)("}\n"); |
| 1705 | } |
| 1706 | |
jsgf | 855d93d | 2003-10-13 22:26:55 +0000 | [diff] [blame] | 1707 | /* |
| 1708 | In pre-2.6 kernels, the kernel didn't distribute signals to threads |
| 1709 | in a thread-group properly, so we need to do it here. |
| 1710 | */ |
| 1711 | void VG_(route_signals)(void) |
| 1712 | { |
| 1713 | static const struct vki_timespec zero = { 0, 0 }; |
| 1714 | static ThreadId start_tid = 1; /* tid to start scanning from */ |
| 1715 | vki_ksigset_t set; |
jsgf | 855d93d | 2003-10-13 22:26:55 +0000 | [diff] [blame] | 1716 | vki_ksiginfo_t si; |
| 1717 | Int sigNo; |
| 1718 | |
| 1719 | vg_assert(VG_(gettid)() == VG_(main_pid)); |
| 1720 | vg_assert(is_correct_sigmask()); |
| 1721 | |
| 1722 | if (!VG_(do_signal_routing)) |
| 1723 | return; |
| 1724 | |
jsgf | 855d93d | 2003-10-13 22:26:55 +0000 | [diff] [blame] | 1725 | /* get the scheduler LWP's signal mask, and use it as the set of |
fitzhardinge | e1c06d8 | 2003-10-30 07:21:44 +0000 | [diff] [blame] | 1726 | signals we're polling for - also block all signals to prevent |
| 1727 | races */ |
| 1728 | VG_(block_all_host_signals) ( &set ); |
jsgf | 855d93d | 2003-10-13 22:26:55 +0000 | [diff] [blame] | 1729 | |
fitzhardinge | e1c06d8 | 2003-10-30 07:21:44 +0000 | [diff] [blame] | 1730 | /* grab any pending signals and add them to the pending signal set */ |
| 1731 | while(VG_(ksigtimedwait)(&set, &si, &zero) > 0) |
| 1732 | VG_(ksigaddset)(&proc_pending, si.si_signo); |
| 1733 | |
| 1734 | /* transfer signals from the process pending set to a particular |
| 1735 | thread which has it unblocked */ |
| 1736 | for(sigNo = 0; sigNo < VKI_KNSIG; sigNo++) { |
jsgf | 855d93d | 2003-10-13 22:26:55 +0000 | [diff] [blame] | 1737 | ThreadId tid; |
| 1738 | ThreadId end_tid; |
| 1739 | Int target = -1; |
| 1740 | |
fitzhardinge | e1c06d8 | 2003-10-30 07:21:44 +0000 | [diff] [blame] | 1741 | if (!VG_(ksigismember)(&proc_pending, sigNo)) |
| 1742 | continue; |
| 1743 | |
jsgf | 855d93d | 2003-10-13 22:26:55 +0000 | [diff] [blame] | 1744 | end_tid = start_tid - 1; |
| 1745 | if (end_tid < 0 || end_tid >= VG_N_THREADS) |
| 1746 | end_tid = VG_N_THREADS-1; |
| 1747 | |
jsgf | 855d93d | 2003-10-13 22:26:55 +0000 | [diff] [blame] | 1748 | /* look for a suitable thread to deliver it to */ |
| 1749 | for(tid = start_tid; |
| 1750 | tid != end_tid; |
| 1751 | tid = (tid + 1) % VG_N_THREADS) { |
| 1752 | ThreadState *tst = &VG_(threads)[tid]; |
| 1753 | |
| 1754 | if (tst->status == VgTs_Empty) |
| 1755 | continue; |
| 1756 | |
| 1757 | if (!VG_(ksigismember)(&tst->sig_mask, sigNo)) { |
| 1758 | vg_assert(tst->proxy != NULL); |
| 1759 | target = tid; |
| 1760 | start_tid = tid; |
| 1761 | break; |
| 1762 | } |
| 1763 | } |
| 1764 | |
fitzhardinge | e1c06d8 | 2003-10-30 07:21:44 +0000 | [diff] [blame] | 1765 | /* found one - deliver it and be done */ |
jsgf | 855d93d | 2003-10-13 22:26:55 +0000 | [diff] [blame] | 1766 | if (target != -1) { |
| 1767 | if (VG_(clo_trace_signals)) |
| 1768 | VG_(message)(Vg_DebugMsg, "Routing signal %d to tid %d", |
| 1769 | sigNo, tid); |
fitzhardinge | e1c06d8 | 2003-10-30 07:21:44 +0000 | [diff] [blame] | 1770 | VG_(proxy_sendsig)(target, sigNo); |
| 1771 | VG_(ksigdelset)(&proc_pending, sigNo); |
jsgf | 855d93d | 2003-10-13 22:26:55 +0000 | [diff] [blame] | 1772 | } |
| 1773 | } |
| 1774 | |
fitzhardinge | e1c06d8 | 2003-10-30 07:21:44 +0000 | [diff] [blame] | 1775 | /* restore signal mask */ |
| 1776 | VG_(restore_all_host_signals) (&set); |
jsgf | 855d93d | 2003-10-13 22:26:55 +0000 | [diff] [blame] | 1777 | } |
sewardj | de4a1d0 | 2002-03-22 01:27:54 +0000 | [diff] [blame] | 1778 | |
sewardj | 018f762 | 2002-05-15 21:13:39 +0000 | [diff] [blame] | 1779 | /* At startup, copy the process' real signal state to the SCSS. |
| 1780 | Whilst doing this, block all real signals. Then calculate SKSS and |
| 1781 | set the kernel to that. Also initialise DCSS. |
sewardj | de4a1d0 | 2002-03-22 01:27:54 +0000 | [diff] [blame] | 1782 | */ |
| 1783 | void VG_(sigstartup_actions) ( void ) |
| 1784 | { |
| 1785 | Int i, ret; |
sewardj | de4a1d0 | 2002-03-22 01:27:54 +0000 | [diff] [blame] | 1786 | vki_ksigset_t saved_procmask; |
| 1787 | vki_kstack_t altstack_info; |
| 1788 | vki_ksigaction sa; |
| 1789 | |
sewardj | 2e93c50 | 2002-04-12 11:12:52 +0000 | [diff] [blame] | 1790 | /* VG_(printf)("SIGSTARTUP\n"); */ |
jsgf | 855d93d | 2003-10-13 22:26:55 +0000 | [diff] [blame] | 1791 | /* Block all signals. saved_procmask remembers the previous mask, |
| 1792 | which the first thread inherits. |
| 1793 | */ |
sewardj | 2e93c50 | 2002-04-12 11:12:52 +0000 | [diff] [blame] | 1794 | VG_(block_all_host_signals)( &saved_procmask ); |
sewardj | de4a1d0 | 2002-03-22 01:27:54 +0000 | [diff] [blame] | 1795 | |
fitzhardinge | e1c06d8 | 2003-10-30 07:21:44 +0000 | [diff] [blame] | 1796 | /* clear process-wide pending signal set */ |
| 1797 | VG_(ksigemptyset)(&proc_pending); |
| 1798 | |
jsgf | 855d93d | 2003-10-13 22:26:55 +0000 | [diff] [blame] | 1799 | /* Set the signal mask which the scheduler LWP should maintain from |
| 1800 | now on. */ |
| 1801 | set_main_sigmask(); |
| 1802 | |
sewardj | 018f762 | 2002-05-15 21:13:39 +0000 | [diff] [blame] | 1803 | /* Copy per-signal settings to SCSS. */ |
| 1804 | for (i = 1; i <= VKI_KNSIG; i++) { |
| 1805 | |
| 1806 | /* Get the old host action */ |
| 1807 | ret = VG_(ksigaction)(i, NULL, &sa); |
| 1808 | vg_assert(ret == 0); |
| 1809 | |
| 1810 | if (VG_(clo_trace_signals)) |
| 1811 | VG_(printf)("snaffling handler 0x%x for signal %d\n", |
| 1812 | (Addr)(sa.ksa_handler), i ); |
| 1813 | |
| 1814 | vg_scss.scss_per_sig[i].scss_handler = sa.ksa_handler; |
| 1815 | vg_scss.scss_per_sig[i].scss_flags = sa.ksa_flags; |
| 1816 | vg_scss.scss_per_sig[i].scss_mask = sa.ksa_mask; |
| 1817 | vg_scss.scss_per_sig[i].scss_restorer = sa.ksa_restorer; |
| 1818 | } |
| 1819 | |
jsgf | 855d93d | 2003-10-13 22:26:55 +0000 | [diff] [blame] | 1820 | /* Our private internal signals are treated as ignored */ |
| 1821 | vg_scss.scss_per_sig[VKI_SIGVGINT].scss_handler = VKI_SIG_IGN; |
| 1822 | vg_scss.scss_per_sig[VKI_SIGVGINT].scss_flags = VKI_SA_SIGINFO; |
| 1823 | VG_(ksigfillset)(&vg_scss.scss_per_sig[VKI_SIGVGINT].scss_mask); |
| 1824 | vg_scss.scss_per_sig[VKI_SIGVGKILL].scss_handler = VKI_SIG_IGN; |
| 1825 | vg_scss.scss_per_sig[VKI_SIGVGKILL].scss_flags = VKI_SA_SIGINFO; |
| 1826 | VG_(ksigfillset)(&vg_scss.scss_per_sig[VKI_SIGVGKILL].scss_mask); |
| 1827 | |
sewardj | 2342c97 | 2002-05-22 23:34:20 +0000 | [diff] [blame] | 1828 | /* Copy the alt stack, if any. */ |
| 1829 | ret = VG_(ksigaltstack)(NULL, &vg_scss.altstack); |
| 1830 | vg_assert(ret == 0); |
| 1831 | |
sewardj | 018f762 | 2002-05-15 21:13:39 +0000 | [diff] [blame] | 1832 | /* Copy the process' signal mask into the root thread. */ |
| 1833 | vg_assert(VG_(threads)[1].status == VgTs_Runnable); |
| 1834 | VG_(threads)[1].sig_mask = saved_procmask; |
jsgf | 855d93d | 2003-10-13 22:26:55 +0000 | [diff] [blame] | 1835 | VG_(proxy_setsigmask)(1); |
sewardj | 018f762 | 2002-05-15 21:13:39 +0000 | [diff] [blame] | 1836 | |
njn | 12a5714 | 2003-04-30 20:49:10 +0000 | [diff] [blame] | 1837 | /* Register an alternative stack for our own signal handler to run on. */ |
sewardj | de4a1d0 | 2002-03-22 01:27:54 +0000 | [diff] [blame] | 1838 | altstack_info.ss_sp = &(VG_(sigstack)[0]); |
njn | 6eba4ef | 2003-05-01 08:06:41 +0000 | [diff] [blame] | 1839 | altstack_info.ss_size = VG_SIGSTACK_SIZE_W * sizeof(UInt); |
sewardj | de4a1d0 | 2002-03-22 01:27:54 +0000 | [diff] [blame] | 1840 | altstack_info.ss_flags = 0; |
| 1841 | ret = VG_(ksigaltstack)(&altstack_info, NULL); |
| 1842 | if (ret != 0) { |
njn | e427a66 | 2002-10-02 11:08:25 +0000 | [diff] [blame] | 1843 | VG_(core_panic)( |
sewardj | de4a1d0 | 2002-03-22 01:27:54 +0000 | [diff] [blame] | 1844 | "vg_sigstartup_actions: couldn't install alternative sigstack"); |
| 1845 | } |
| 1846 | if (VG_(clo_trace_signals)) { |
| 1847 | VG_(message)(Vg_DebugExtraMsg, |
| 1848 | "vg_sigstartup_actions: sigstack installed ok"); |
| 1849 | } |
| 1850 | |
sewardj | 7a61d91 | 2002-04-25 01:27:35 +0000 | [diff] [blame] | 1851 | /* DEBUGGING HACK */ |
| 1852 | /* VG_(ksignal)(VKI_SIGUSR1, &VG_(oursignalhandler)); */ |
| 1853 | |
sewardj | 018f762 | 2002-05-15 21:13:39 +0000 | [diff] [blame] | 1854 | /* Calculate SKSS and apply it. This also sets the initial kernel |
| 1855 | mask we need to run with. */ |
| 1856 | VG_(handle_SCSS_change)( True /* forced update */ ); |
jsgf | 855d93d | 2003-10-13 22:26:55 +0000 | [diff] [blame] | 1857 | |
sewardj | de4a1d0 | 2002-03-22 01:27:54 +0000 | [diff] [blame] | 1858 | } |
| 1859 | |
| 1860 | |
| 1861 | /* Copy the process' sim signal state to the real state, |
| 1862 | for when we transfer from the simulated to real CPU. |
| 1863 | PROBLEM: what if we're running a signal handler when we |
| 1864 | get here? Hmm. |
| 1865 | I guess we wind up in vg_signalreturn_bogusRA, *or* the |
| 1866 | handler has done/will do a longjmp, in which case we're ok. |
sewardj | de4a1d0 | 2002-03-22 01:27:54 +0000 | [diff] [blame] | 1867 | */ |
| 1868 | void VG_(sigshutdown_actions) ( void ) |
| 1869 | { |
| 1870 | Int i, ret; |
| 1871 | |
sewardj | de4a1d0 | 2002-03-22 01:27:54 +0000 | [diff] [blame] | 1872 | vki_ksigset_t saved_procmask; |
| 1873 | vki_ksigaction sa; |
| 1874 | |
sewardj | 2e93c50 | 2002-04-12 11:12:52 +0000 | [diff] [blame] | 1875 | VG_(block_all_host_signals)( &saved_procmask ); |
sewardj | de4a1d0 | 2002-03-22 01:27:54 +0000 | [diff] [blame] | 1876 | |
sewardj | 018f762 | 2002-05-15 21:13:39 +0000 | [diff] [blame] | 1877 | /* Copy per-signal settings from SCSS. */ |
sewardj | b48e500 | 2002-05-13 00:16:03 +0000 | [diff] [blame] | 1878 | for (i = 1; i <= VKI_KNSIG; i++) { |
sewardj | 018f762 | 2002-05-15 21:13:39 +0000 | [diff] [blame] | 1879 | |
| 1880 | sa.ksa_handler = vg_scss.scss_per_sig[i].scss_handler; |
| 1881 | sa.ksa_flags = vg_scss.scss_per_sig[i].scss_flags; |
| 1882 | sa.ksa_mask = vg_scss.scss_per_sig[i].scss_mask; |
| 1883 | sa.ksa_restorer = vg_scss.scss_per_sig[i].scss_restorer; |
| 1884 | |
| 1885 | if (VG_(clo_trace_signals)) |
| 1886 | VG_(printf)("restoring handler 0x%x for signal %d\n", |
| 1887 | (Addr)(sa.ksa_handler), i ); |
| 1888 | |
sewardj | e8fb72e | 2002-06-28 02:08:28 +0000 | [diff] [blame] | 1889 | /* Set the old host action */ |
sewardj | 018f762 | 2002-05-15 21:13:39 +0000 | [diff] [blame] | 1890 | ret = VG_(ksigaction)(i, &sa, NULL); |
sewardj | e8fb72e | 2002-06-28 02:08:28 +0000 | [diff] [blame] | 1891 | if (i != VKI_SIGKILL && i != VKI_SIGSTOP) |
| 1892 | vg_assert(ret == 0); |
sewardj | de4a1d0 | 2002-03-22 01:27:54 +0000 | [diff] [blame] | 1893 | } |
| 1894 | |
sewardj | 2342c97 | 2002-05-22 23:34:20 +0000 | [diff] [blame] | 1895 | /* Restore the sig alt stack. */ |
| 1896 | ret = VG_(ksigaltstack)(&vg_scss.altstack, NULL); |
| 1897 | vg_assert(ret == 0); |
| 1898 | |
sewardj | 018f762 | 2002-05-15 21:13:39 +0000 | [diff] [blame] | 1899 | /* A bit of a kludge -- set the sigmask to that of the root |
| 1900 | thread. */ |
| 1901 | vg_assert(VG_(threads)[1].status != VgTs_Empty); |
| 1902 | VG_(restore_all_host_signals)( &VG_(threads)[1].sig_mask ); |
sewardj | de4a1d0 | 2002-03-22 01:27:54 +0000 | [diff] [blame] | 1903 | } |
| 1904 | |
| 1905 | |
sewardj | de4a1d0 | 2002-03-22 01:27:54 +0000 | [diff] [blame] | 1906 | /*--------------------------------------------------------------------*/ |
| 1907 | /*--- end vg_signals.c ---*/ |
| 1908 | /*--------------------------------------------------------------------*/ |