diff options
| author | Zbigniew Jędrzejewski-Szmek <zbyszek@in.waw.pl> | 2016-08-11 04:51:00 -0400 |
|---|---|---|
| committer | Lennart Poettering <lennart@poettering.net> | 2016-08-11 10:51:00 +0200 |
| commit | 6998b54093831fac92e2b1e251659e64d56e1df6 (patch) | |
| tree | 99868461576e4753de4f36527064883a8239235b | |
| parent | ff0bb1ed93fb80cdc2b456894e0d1567ddd97bdc (diff) | |
coredump: treat RLIMIT_CORE below page size as disabling coredumps (#3932)
The kernel treats values below a certain threshold (minfmt->min_coredump
which is initialized do ELF_EXEC_PAGESIZE, which varies between architectures,
but is usually the same as PAGE_SIZE) as disabling coredumps [1].
Any core image below ELF_EXEC_PAGESIZE will yield an invalid backtrace anyway [2],
so follow the kernel and not try to parse or store such images.
[1] https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/tree/fs/coredump.c#n660
[2] systemd-coredump[16260]: Process 16258 (sleep) of user 1002 dumped core.
Stack trace of thread 16258:
#0 0x00007f1d8b3d3810 n/a (n/a)
https://bugzilla.redhat.com/show_bug.cgi?id=1309172#c19
| -rw-r--r-- | src/coredump/coredump.c | 8 |
1 files changed, 5 insertions, 3 deletions
diff --git a/src/coredump/coredump.c b/src/coredump/coredump.c index e3d17c864d..be724aed4e 100644 --- a/src/coredump/coredump.c +++ b/src/coredump/coredump.c @@ -327,9 +327,11 @@ static int save_external_coredump( r = safe_atou64(context[CONTEXT_RLIMIT], &rlimit); if (r < 0) return log_error_errno(r, "Failed to parse resource limit: %s", context[CONTEXT_RLIMIT]); - if (rlimit <= 0) { - /* Is coredumping disabled? Then don't bother saving/processing the coredump */ - log_info("Core Dumping has been disabled for process %s (%s).", context[CONTEXT_PID], context[CONTEXT_COMM]); + if (rlimit < page_size()) { + /* Is coredumping disabled? Then don't bother saving/processing the coredump. + * Anything below PAGE_SIZE cannot give a readable coredump (the kernel uses + * ELF_EXEC_PAGESIZE which is not easily accessible, but is usually the same as PAGE_SIZE. */ + log_info("Core dumping has been disabled for process %s (%s).", context[CONTEXT_PID], context[CONTEXT_COMM]); return -EBADSLT; } |