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| author |   Mike Frysinger <vapier@gentoo.org> | 2021-10-28 01:49:33 -0400 |
|---|---|---|
| committer | Mike Frysinger <vapier@gentoo.org> | 2021-10-28 01:49:33 -0400 |
| commit | a374b1f829a07cce3eb708f078a2a70f9bc4d975 (patch) | |
| tree | 2c91872c23cdc3ed5c184e78f9c52bd951172711 | |
| parent | libsandbox: drop lstat check for symlink funcs (diff) | |
| download | sandbox-a374b1f829a07cce3eb708f078a2a70f9bc4d975.tar.gz sandbox-a374b1f829a07cce3eb708f078a2a70f9bc4d975.tar.bz2 sandbox-a374b1f829a07cce3eb708f078a2a70f9bc4d975.zip | |
libsandbox: fix signal pass through with ptrace main loopv2.28
When we're notified that the child has received a signal, we need to
pass it through since we don't care about signals. We did that, but
using PTRACE_CONT which causes the process to just resume, and then
we'd call PTRACE_SYSCALL on that resumed state. When the pass thru
logic was a signal handler, PTRACE_CONT was correct since it would
come in while in the middle of PTRACE_SYSCALL, but after the rewrite
of the main loop, it's now the wrong call. Pass the signal back to
the existing PTRACE_SYSCALL call so that we stay in the main loop
and get notified on the next syscall event.
Closes: https://bugs.gentoo.org/820407
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
| -rw-r--r-- | libsandbox/trace.c | 7 |
1 files changed, 5 insertions, 2 deletions
diff --git a/libsandbox/trace.c b/libsandbox/trace.c index b7e65b4..d53051d 100644 --- a/libsandbox/trace.c +++ b/libsandbox/trace.c @@ -405,13 +405,16 @@ static void trace_loop(void) long ret; int status, sig; const struct syscall_entry *tbl_after_fork; + void *data; before_exec = true; before_syscall = false; fake_syscall_ret = false; tbl_after_fork = NULL; + data = NULL; do { - ret = do_ptrace(PTRACE_SYSCALL, NULL, NULL); + ret = do_ptrace(PTRACE_SYSCALL, NULL, data); + data = NULL; waitpid(trace_pid, &status, 0); event = (unsigned)status >> 16; @@ -444,7 +447,7 @@ static void trace_loop(void) * and we'll exit then. */ sb_debug("passing signal through %s (%i)", strsig(sig), sig); - do_ptrace(PTRACE_CONT, NULL, (void *)(uintptr_t)(sig)); + data = (void *)(uintptr_t)(sig); continue; } |