Remove support for systems without PTRACE_SETOPTIONS
Assume that the kernel is v2.5.46 or newer, i.e. PTRACE_SETOPTIONS
and PTRACE_O_TRACESYSGOOD|PTRACE_O_TRACEEXEC|PTRACE_O_TRACECLONE
are universally available.
This change removes all code that implemented post-execve SIGTRAP
handling and fork/vfork/clone->CLONE_PTRACE substitution.
* defs.h (TCB_BPTSET, TCB_WAITEXECVE): Remove macros.
(need_fork_exec_workarounds, setbpt, clearbpt): Remove declarations.
* strace.c (need_fork_exec_workarounds,
test_ptrace_setoptions_followfork, test_ptrace_setoptions_for_all):
Remove.
(syscall_trap_sig): Set to (SIGTRAP | 0x80).
(ptrace_setoptions): Set to (PTRACE_O_TRACESYSGOOD | PTRACE_O_TRACEEXEC).
(detach): Do not test for TCB_BPTSET.
(init): Do not call test_ptrace_setoptions_followfork and
test_ptrace_setoptions_for_all. Do not test for TCB_BPTSET.
* syscall.c (syscall_fixup_on_sysenter, internal_fork, internal_exec,
syscall_fixup_for_fork_exec, syscall_fixup_on_sysexit): Remove.
(trace_syscall_entering): Do not test for TCB_WAITEXECVE. Do not call
syscall_fixup_on_sysenter and syscall_fixup_for_fork_exec.
(trace_syscall_exiting): Do not call syscall_fixup_on_sysexit and
syscall_fixup_for_fork_exec.
[IA64] (ia64_ia32mode): Make static.
* linux/ia64/arch_regs.h (ia64_ia32mode): Remove declaration.
* util.c: Do not include "syscall.h".
(arg_setup, get_arg0, get_arg1, set_arg0, set_arg1, restore_arg0,
restore_arg1, arg_finish_change, change_syscall, setbpt, clearbpt):
Remove.
* tests/ptrace_setoptions.test: Remove.
* tests/Makefile.am (TESTS): Remove it.
diff --git a/syscall.c b/syscall.c
index c805774..70ba8a0 100644
--- a/syscall.c
+++ b/syscall.c
@@ -702,10 +702,10 @@
# define ARCH_REGS_FOR_GETREGSET x86_regs_union
# define ARCH_IOVEC_FOR_GETREGSET x86_io
#elif defined(IA64)
-bool ia64_ia32mode = 0; /* not static */
+static bool ia64_ia32mode;
static long ia64_r8, ia64_r10;
#elif defined(POWERPC)
-struct pt_regs ppc_regs;
+struct pt_regs ppc_regs; /* not static */
# define ARCH_REGS_FOR_GETREGS ppc_regs
#elif defined(M68K)
static long m68k_d0;
@@ -771,7 +771,7 @@
#elif defined(CRISV10) || defined(CRISV32)
static long cris_r10;
#elif defined(TILE)
-struct pt_regs tile_regs;
+struct pt_regs tile_regs; /* not static */
# define ARCH_REGS_FOR_GETREGS tile_regs
#elif defined(MICROBLAZE)
static long microblaze_r3;
@@ -1607,173 +1607,6 @@
return val >= max;
}
-/* Called at each syscall entry.
- * Returns:
- * 0: "ignore this ptrace stop", bail out of trace_syscall_entering() silently.
- * 1: ok, continue in trace_syscall_entering().
- * other: error, trace_syscall_entering() should print error indicator
- * ("????" etc) and bail out.
- */
-static int
-syscall_fixup_on_sysenter(struct tcb *tcp)
-{
- /* Do we have post-execve SIGTRAP suppressed? */
- if (ptrace_setoptions & PTRACE_O_TRACEEXEC)
- return 1;
-
- /*
- * No, unfortunately. Apply -ENOSYS heuristics.
- * We don't have to workaround SECCOMP_RET_ERRNO side effects
- * because any kernel with SECCOMP_RET_ERRNO support surely
- * implements PTRACE_O_TRACEEXEC.
- */
-#if defined(I386)
- if (i386_regs.eax != -ENOSYS) {
- if (debug_flag)
- fprintf(stderr, "not a syscall entry (eax = %ld)\n",
- i386_regs.eax);
- return 0;
- }
-#elif defined(X86_64) || defined(X32)
- if (x86_io.iov_len == sizeof(i386_regs)) {
- if ((int) i386_regs.eax != -ENOSYS) {
- if (debug_flag)
- fprintf(stderr,
- "not a syscall entry (eax = %d)\n",
- (int) i386_regs.eax);
- return 0;
- }
- } else {
- if ((long long) x86_64_regs.rax != -ENOSYS) {
- if (debug_flag)
- fprintf(stderr,
- "not a syscall entry (rax = %lld)\n",
- (long long) x86_64_regs.rax);
- return 0;
- }
- }
-#elif defined(M68K)
- /* TODO? Eliminate upeek's in arches below like we did in x86 */
- if (upeek(tcp->pid, 4*PT_D0, &m68k_d0) < 0)
- return -1;
- if (m68k_d0 != -ENOSYS) {
- if (debug_flag)
- fprintf(stderr, "not a syscall entry (d0 = %ld)\n", m68k_d0);
- return 0;
- }
-#elif defined(IA64)
- if (upeek(tcp->pid, PT_R10, &ia64_r10) < 0)
- return -1;
- if (upeek(tcp->pid, PT_R8, &ia64_r8) < 0)
- return -1;
- if (ia64_ia32mode && ia64_r8 != -ENOSYS) {
- if (debug_flag)
- fprintf(stderr, "not a syscall entry (r8 = %ld)\n", ia64_r8);
- return 0;
- }
-#elif defined(CRISV10) || defined(CRISV32)
- if (upeek(tcp->pid, 4*PT_R10, &cris_r10) < 0)
- return -1;
- if (cris_r10 != -ENOSYS) {
- if (debug_flag)
- fprintf(stderr, "not a syscall entry (r10 = %ld)\n", cris_r10);
- return 0;
- }
-#elif defined(MICROBLAZE)
- if (upeek(tcp->pid, 3 * 4, µblaze_r3) < 0)
- return -1;
- if (microblaze_r3 != -ENOSYS) {
- if (debug_flag)
- fprintf(stderr, "not a syscall entry (r3 = %ld)\n", microblaze_r3);
- return 0;
- }
-#endif
- return 1;
-}
-
-static void
-internal_fork(struct tcb *tcp)
-{
-#if defined S390 || defined S390X || defined CRISV10 || defined CRISV32
-# define ARG_FLAGS 1
-#else
-# define ARG_FLAGS 0
-#endif
-#ifndef CLONE_UNTRACED
-# define CLONE_UNTRACED 0x00800000
-#endif
- if ((ptrace_setoptions
- & (PTRACE_O_TRACECLONE | PTRACE_O_TRACEFORK | PTRACE_O_TRACEVFORK))
- == (PTRACE_O_TRACECLONE | PTRACE_O_TRACEFORK | PTRACE_O_TRACEVFORK))
- return;
-
- if (!followfork)
- return;
-
- if (entering(tcp)) {
- /*
- * We won't see the new child if clone is called with
- * CLONE_UNTRACED, so we keep the same logic with that option
- * and don't trace it.
- */
- if ((tcp->s_ent->sys_func == sys_clone)
- && (tcp->u_arg[ARG_FLAGS] & CLONE_UNTRACED)
- )
- return;
- setbpt(tcp);
- } else {
- if (tcp->flags & TCB_BPTSET)
- clearbpt(tcp);
- }
-}
-
-#if defined(TCB_WAITEXECVE)
-static void
-internal_exec(struct tcb *tcp)
-{
- /* Maybe we have post-execve SIGTRAP suppressed? */
- if (ptrace_setoptions & PTRACE_O_TRACEEXEC)
- return; /* yes, no need to do anything */
-
- if (exiting(tcp) && syserror(tcp))
- /* Error in execve, no post-execve SIGTRAP expected */
- tcp->flags &= ~TCB_WAITEXECVE;
- else
- tcp->flags |= TCB_WAITEXECVE;
-}
-#endif
-
-static void
-syscall_fixup_for_fork_exec(struct tcb *tcp)
-{
- /*
- * We must always trace a few critical system calls in order to
- * correctly support following forks in the presence of tracing
- * qualifiers.
- */
- int (*func)();
-
- func = tcp->s_ent->sys_func;
-
- if ( sys_fork == func
- || sys_clone == func
- ) {
- internal_fork(tcp);
- return;
- }
-
-#if defined(TCB_WAITEXECVE)
- if ( sys_execve == func
-# if defined(SPARC) || defined(SPARC64)
- || sys_execv == func
-# endif
- ) {
- internal_exec(tcp);
- return;
- }
-#endif
-}
-
/* Return -1 on error or 1 on success (never 0!) */
static int
get_syscall_args(struct tcb *tcp)
@@ -2008,24 +1841,11 @@
{
int res, scno_good;
-#if defined TCB_WAITEXECVE
- if (tcp->flags & TCB_WAITEXECVE) {
- /* This is the post-execve SIGTRAP. */
- tcp->flags &= ~TCB_WAITEXECVE;
- return 0;
- }
-#endif
-
scno_good = res = (get_regs_error ? -1 : get_scno(tcp));
if (res == 0)
return res;
- if (res == 1) {
- res = syscall_fixup_on_sysenter(tcp);
- if (res == 0)
- return res;
- if (res == 1)
- res = get_syscall_args(tcp);
- }
+ if (res == 1)
+ res = get_syscall_args(tcp);
if (res != 1) {
printleader(tcp);
@@ -2068,9 +1888,6 @@
}
#endif
- if (need_fork_exec_workarounds)
- syscall_fixup_for_fork_exec(tcp);
-
if (!(tcp->qual_flg & QUAL_TRACE)
|| (tracing_paths && !pathtrace_match(tcp))
) {
@@ -2170,23 +1987,6 @@
return 1;
}
-/* Called at each syscall exit */
-static void
-syscall_fixup_on_sysexit(struct tcb *tcp)
-{
-#if defined(S390) || defined(S390X)
- if ((tcp->flags & TCB_WAITEXECVE)
- && (s390_gpr2 == -ENOSYS || s390_gpr2 == tcp->scno)) {
- /*
- * Return from execve.
- * Fake a return value of zero. We leave the TCB_WAITEXECVE
- * flag set for the post-execve SIGTRAP to see and reset.
- */
- s390_gpr2 = 0;
- }
-#endif
-}
-
/* Returns:
* 1: ok, continue in trace_syscall_exiting().
* -1: error, trace_syscall_exiting() should print error indicator
@@ -2510,10 +2310,7 @@
#endif
res = (get_regs_error ? -1 : get_syscall_result(tcp));
if (res == 1) {
- syscall_fixup_on_sysexit(tcp); /* never fails */
get_error(tcp); /* never fails */
- if (need_fork_exec_workarounds)
- syscall_fixup_for_fork_exec(tcp);
if (filtered(tcp) || hide_log_until_execve)
goto ret;
}