linux-stable/tools
Naveen N. Rao 4b335e1e0d perf trace: Fix SIGSEGV when processing syscall args
On powerpc, 'perf trace' is crashing with a SIGSEGV when trying to
process a perf.data file created with 'perf trace record -p':

  #0  0x00000001225b8988 in syscall_arg__scnprintf_augmented_string <snip> at builtin-trace.c:1492
  #1  syscall_arg__scnprintf_filename <snip> at builtin-trace.c:1492
  #2  syscall_arg__scnprintf_filename <snip> at builtin-trace.c:1486
  #3  0x00000001225bdd9c in syscall_arg_fmt__scnprintf_val <snip> at builtin-trace.c:1973
  #4  syscall__scnprintf_args <snip> at builtin-trace.c:2041
  #5  0x00000001225bff04 in trace__sys_enter <snip> at builtin-trace.c:2319

That points to the below code in tools/perf/builtin-trace.c:
	/*
	 * If this is raw_syscalls.sys_enter, then it always comes with the 6 possible
	 * arguments, even if the syscall being handled, say "openat", uses only 4 arguments
	 * this breaks syscall__augmented_args() check for augmented args, as we calculate
	 * syscall->args_size using each syscalls:sys_enter_NAME tracefs format file,
	 * so when handling, say the openat syscall, we end up getting 6 args for the
	 * raw_syscalls:sys_enter event, when we expected just 4, we end up mistakenly
	 * thinking that the extra 2 u64 args are the augmented filename, so just check
	 * here and avoid using augmented syscalls when the evsel is the raw_syscalls one.
	 */
	if (evsel != trace->syscalls.events.sys_enter)
		augmented_args = syscall__augmented_args(sc, sample, &augmented_args_size, trace->raw_augmented_syscalls_args_size);

As the comment points out, we should not be trying to augment the args
for raw_syscalls. However, when processing a perf.data file, we are not
initializing those properly. Fix the same.

Reported-by: Claudio Carvalho <cclaudio@linux.ibm.com>
Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: http://lore.kernel.org/lkml/20220707090900.572584-1-naveen.n.rao@linux.vnet.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2022-07-17 10:59:52 -03:00
..
accounting delayacct: track delays from write-protect copy 2022-06-01 15:55:25 -07:00
arch tools arch x86: Sync the msr-index.h copy with the kernel sources 2022-07-17 10:50:50 -03:00
bootconfig
bpf
build
certs
cgroup
counter
debugging
edid
firewire
firmware
gpio
hv
iio
include tools headers UAPI: Sync linux/kvm.h with the kernel sources 2022-07-17 10:14:07 -03:00
io_uring
kvm/kvm_stat tools/kvm_stat: fix display of error when multiple processes are found 2022-06-15 08:14:20 -04:00
laptop
leds
lib libperf evsel: Open shouldn't leak fd on failure 2022-06-19 10:41:43 -03:00
memory-model
objtool Just when you thought that all the speculation bugs were addressed and 2022-07-11 18:15:25 -07:00
pci
pcmcia
perf perf trace: Fix SIGSEGV when processing syscall args 2022-07-17 10:59:52 -03:00
power
rcu
scripts
spi
testing selftests/net: test nexthop without gw 2022-07-14 14:41:19 +02:00
thermal
time
tracing rtla: Remove procps-ng dependency 2022-05-26 15:20:46 -04:00
usb
virtio
vm
wmi
Makefile