Improve sigreturn decoding on x86 to show RT signal bits too.
This includes decoding of 32-bit sigreturn by 64-bit strace,
which previously wasn't done.
Added a test for it.
Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>
diff --git a/defs.h b/defs.h
index 6e0bd88..09488a2 100644
--- a/defs.h
+++ b/defs.h
@@ -378,8 +378,8 @@
# define PERSONALITY0_WORDSIZE (int)(sizeof(long))
#endif
-#if defined(I386)
-extern struct user_regs_struct i386_regs;
+#if defined(I386) || defined(X86_64)
+extern uint32_t *const i386_esp_ptr;
#elif defined(IA64)
extern bool ia64_ia32mode;
#elif defined(SPARC) || defined(SPARC64)
diff --git a/signal.c b/signal.c
index 06cb675..e433306 100644
--- a/signal.c
+++ b/signal.c
@@ -70,35 +70,8 @@
# include <asm/sigcontext.h>
# endif
#else /* !HAVE_ASM_SIGCONTEXT_H */
-# if defined I386 && !defined HAVE_STRUCT_SIGCONTEXT_STRUCT
-struct sigcontext_struct {
- unsigned short gs, __gsh;
- unsigned short fs, __fsh;
- unsigned short es, __esh;
- unsigned short ds, __dsh;
- unsigned long edi;
- unsigned long esi;
- unsigned long ebp;
- unsigned long esp;
- unsigned long ebx;
- unsigned long edx;
- unsigned long ecx;
- unsigned long eax;
- unsigned long trapno;
- unsigned long err;
- unsigned long eip;
- unsigned short cs, __csh;
- unsigned long eflags;
- unsigned long esp_at_signal;
- unsigned short ss, __ssh;
- unsigned long i387;
- unsigned long oldmask;
- unsigned long cr2;
-};
-# else /* !I386 */
-# if defined M68K && !defined HAVE_STRUCT_SIGCONTEXT
-struct sigcontext
-{
+# if defined M68K && !defined HAVE_STRUCT_SIGCONTEXT
+struct sigcontext {
unsigned long sc_mask;
unsigned long sc_usp;
unsigned long sc_d0;
@@ -109,9 +82,53 @@
unsigned long sc_pc;
unsigned short sc_formatvec;
};
-# endif /* M68K */
-# endif /* !I386 */
+# endif /* M68K */
#endif /* !HAVE_ASM_SIGCONTEXT_H */
+#if defined(I386) || defined(X86_64)
+struct i386_sigcontext_struct {
+ uint16_t gs, __gsh;
+ uint16_t fs, __fsh;
+ uint16_t es, __esh;
+ uint16_t ds, __dsh;
+ uint32_t edi;
+ uint32_t esi;
+ uint32_t ebp;
+ uint32_t esp;
+ uint32_t ebx;
+ uint32_t edx;
+ uint32_t ecx;
+ uint32_t eax;
+ uint32_t trapno;
+ uint32_t err;
+ uint32_t eip;
+ uint16_t cs, __csh;
+ uint32_t eflags;
+ uint32_t esp_at_signal;
+ uint16_t ss, __ssh;
+ uint32_t i387;
+ uint32_t oldmask;
+ uint32_t cr2;
+};
+struct i386_fpstate {
+ uint32_t cw;
+ uint32_t sw;
+ uint32_t tag;
+ uint32_t ipoff;
+ uint32_t cssel;
+ uint32_t dataoff;
+ uint32_t datasel;
+ uint8_t st[8][10]; /* 8*10 bytes: FP regs */
+ uint16_t status;
+ uint16_t magic;
+ uint32_t fxsr_env[6];
+ uint32_t mxcsr;
+ uint32_t reserved;
+ uint8_t stx[8][16]; /* 8*16 bytes: FP regs, each padded to 16 bytes */
+ uint8_t xmm[8][16]; /* 8 XMM regs */
+ uint32_t padding1[44];
+ uint32_t padding2[12]; /* union with struct _fpx_sw_bytes */
+};
+#endif
#ifndef NSIG
# warning: NSIG is not defined, using 32
@@ -288,10 +305,13 @@
char sep;
char *s;
+ /* Note: nsignals = ARRAY_SIZE(signalent[]),
+ * and that array may not have SIGRTnn.
+ */
maxsigs = nsignals;
#ifdef __SIGRTMAX
if (rt)
- maxsigs = __SIGRTMAX; /* instead */
+ maxsigs = __SIGRTMAX + 1; /* instead */
#endif
s = stpcpy(outstr, str);
nsigs = 0;
@@ -308,23 +328,17 @@
sep = '[';
for (i = 1; i < maxsigs; i++) {
if (sigismember(mask, i) == show_members) {
- /* real-time signals on solaris don't have
- * signalent entries
- */
- char tsig[40];
*s++ = sep;
if (i < nsignals) {
s = stpcpy(s, signalent[i] + 3);
}
#ifdef SIGRTMIN
else if (i >= __SIGRTMIN && i <= __SIGRTMAX) {
- sprintf(tsig, "RT_%u", i - __SIGRTMIN);
- s = stpcpy(s, tsig);
+ s += sprintf(s, "RT_%u", i - __SIGRTMIN);
}
#endif /* SIGRTMIN */
else {
- sprintf(tsig, "%u", i);
- s = stpcpy(s, tsig);
+ s += sprintf(s, "%u", i);
}
sep = ' ';
}
@@ -832,19 +846,28 @@
return 0;
tprints(sprintsigmask(") (mask ", (sigset_t *)&sc.oldmask[0], 0));
}
-#elif defined(I386)
+#elif defined(I386) || defined(X86_64)
+# if defined(X86_64)
+ if (current_personality == 0) /* 64-bit */
+ return 0;
+# endif
if (entering(tcp)) {
- struct sigcontext_struct sc;
- /* Note: on i386, sc is followed on stack by struct fpstate
+ struct {
+ struct i386_sigcontext_struct sc;
+ struct i386_fpstate fp;
+ uint32_t extramask[1];
+ } signal_stack;
+ /* On i386, sc is followed on stack by struct fpstate
* and after it an additional u32 extramask[1] which holds
- * upper half of the mask. We can fetch it there
- * if/when we'd want to display the full mask...
+ * upper half of the mask.
*/
sigset_t sigm;
- if (umove(tcp, i386_regs.esp, &sc) < 0)
+ if (umove(tcp, *i386_esp_ptr, &signal_stack) < 0)
return 0;
- long_to_sigset(sc.oldmask, &sigm);
- tprints(sprintsigmask(") (mask ", &sigm, 0));
+ sigemptyset(&sigm);
+ ((uint32_t*)&sigm)[0] = signal_stack.sc.oldmask;
+ ((uint32_t*)&sigm)[1] = signal_stack.extramask[0];
+ tprints(sprintsigmask(") (mask ", &sigm, /*RT sigs too?:*/ 1));
}
#elif defined(IA64)
if (entering(tcp)) {
@@ -993,8 +1016,6 @@
long_to_sigset(sc.oldmask, &sigm);
tprints(sprintsigmask(") (mask ", &sigm, 0));
}
-#elif defined(X86_64)
- /* no need to remind */
#elif defined(XTENSA)
/* Xtensa only has rt_sys_sigreturn */
#else
diff --git a/syscall.c b/syscall.c
index 2715cea..a27fee9 100644
--- a/syscall.c
+++ b/syscall.c
@@ -682,7 +682,8 @@
#endif
#if defined(I386)
-struct user_regs_struct i386_regs;
+static struct user_regs_struct i386_regs;
+uint32_t *const i386_esp_ptr = &i386_regs.esp;
# define ARCH_REGS_FOR_GETREGSET i386_regs
#elif defined(X86_64) || defined(X32)
/*
@@ -716,6 +717,7 @@
} x86_regs_union;
# define x86_64_regs x86_regs_union.x86_64_r
# define i386_regs x86_regs_union.i386_r
+uint32_t *const i386_esp_ptr = &i386_regs.esp;
static struct iovec x86_io = {
.iov_base = &x86_regs_union
};
diff --git a/test/.gitignore b/test/.gitignore
index ce242fd..7eb39cf 100644
--- a/test/.gitignore
+++ b/test/.gitignore
@@ -10,3 +10,4 @@
threaded_execve
mtd
ubi
+sigreturn
diff --git a/test/Makefile b/test/Makefile
index 97ae746..92142b1 100644
--- a/test/Makefile
+++ b/test/Makefile
@@ -3,7 +3,7 @@
PROGS = \
vfork fork sig skodic clone leaderkill childthread \
sigkill_rain wait_must_be_interruptible threaded_execve \
- mtd ubi
+ mtd ubi sigreturn
all: $(PROGS)
diff --git a/test/sigreturn.c b/test/sigreturn.c
new file mode 100644
index 0000000..246a3ce
--- /dev/null
+++ b/test/sigreturn.c
@@ -0,0 +1,30 @@
+/*
+ * Check that strace output contains RT_1 RT_3 RT_31 RT_32 here:
+ * rt_sigprocmask(SIG_BLOCK, [CHLD RT_1 RT_3 RT_31 RT_32], NULL, 8) = 0
+ * and here:
+ * sigreturn() (mask [CHLD RT_1 RT_3 RT_31 RT_32]) = 0
+ *
+ * On x86, both 32-bit and 64-bit strace needs to be checked.
+ */
+#include <stdlib.h>
+#include <unistd.h>
+#include <signal.h>
+
+void null_handler(int sig)
+{
+}
+
+int main(int argc, char *argv[])
+{
+ sigset_t set;
+ sigemptyset(&set);
+ sigaddset(&set, SIGCHLD);
+ sigaddset(&set, 33);
+ sigaddset(&set, 35);
+ sigaddset(&set, 63);
+ sigaddset(&set, 64);
+ sigprocmask(SIG_BLOCK, &set, NULL);
+ signal(SIGWINCH, null_handler);
+ raise(SIGWINCH);
+ return 0;
+}