Commit 2f0edac5555983dc28033acce8a355f588fd01b2
Committed by
Linus Torvalds
1 parent
25baa35bef
Exists in
master
and in
7 other branches
ptrace: change tracehook_report_syscall_exit() to handle stepping
Suggested by Roland. Change tracehook_report_syscall_exit() to look at step flag and send the trap signal if needed. This change affects ia64, microblaze, parisc, powerpc, sh. They pass nonzero "step" argument to tracehook but since it was ignored the tracee reports via ptrace_notify(), this is not right and not consistent. - PTRACE_SETSIGINFO doesn't work - if the tracer resumes the tracee with signr != 0 the new signal is generated rather than delivering it - If PT_TRACESYSGOOD is set the tracee reports the wrong exit_code I don't have a powerpc machine, but I think this test-case should see the difference: #include <unistd.h> #include <sys/ptrace.h> #include <sys/wait.h> #include <assert.h> #include <stdio.h> int main(void) { int pid, status; if (!(pid = fork())) { assert(ptrace(PTRACE_TRACEME) == 0); kill(getpid(), SIGSTOP); getppid(); return 0; } assert(pid == wait(&status)); assert(ptrace(PTRACE_SETOPTIONS, pid, 0, PTRACE_O_TRACESYSGOOD) == 0); assert(ptrace(PTRACE_SYSCALL, pid, 0,0) == 0); assert(pid == wait(&status)); assert(ptrace(PTRACE_SINGLESTEP, pid, 0,0) == 0); assert(pid == wait(&status)); if (status == 0x57F) return 0; printf("kernel bug: status=%X shouldn't have 0x80\n", status); return 1; } Signed-off-by: Oleg Nesterov <oleg@redhat.com> Acked-by: Roland McGrath <roland@redhat.com> Cc: <linux-arch@vger.kernel.org> Cc: Ingo Molnar <mingo@elte.hu> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Showing 1 changed file with 7 additions and 0 deletions Side-by-side Diff
include/linux/tracehook.h
... | ... | @@ -134,6 +134,13 @@ |
134 | 134 | */ |
135 | 135 | static inline void tracehook_report_syscall_exit(struct pt_regs *regs, int step) |
136 | 136 | { |
137 | + if (step) { | |
138 | + siginfo_t info; | |
139 | + user_single_step_siginfo(current, regs, &info); | |
140 | + force_sig_info(SIGTRAP, &info, current); | |
141 | + return; | |
142 | + } | |
143 | + | |
137 | 144 | ptrace_report_syscall(regs); |
138 | 145 | } |
139 | 146 |