tools lib traceevent: Fix buffer overflow in arg_eval

Fix buffer overflow observed when running perf test.

The overflow is when trying to evaluate "1ULL << (64 - 1)" which is
resulting in -9223372036854775808 which overflows the 20 character
buffer.

If is possible this bug has been reported before but I still don't see
any fix checked in:

See: https://www.spinics.net/lists/linux-perf-users/msg07714.html

Reported-by: Michael Sartain <mikesart@fastmail.com>
Reported-by: Mathias Krause <minipli@googlemail.com>
Signed-off-by: Tony Jones <tonyj@suse.de>
Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Fixes: f7d82350e5 ("tools/events: Add files to create libtraceevent.a")
Link: http://lkml.kernel.org/r/20190228015532.8941-1-tonyj@suse.de
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This commit is contained in:
Tony Jones 2019-02-27 17:55:32 -08:00 committed by Arnaldo Carvalho de Melo
parent 4d6101f5fd
commit 7c5b019e3a

View File

@ -2457,7 +2457,7 @@ static int arg_num_eval(struct tep_print_arg *arg, long long *val)
static char *arg_eval (struct tep_print_arg *arg)
{
long long val;
static char buf[20];
static char buf[24];
switch (arg->type) {
case TEP_PRINT_ATOM: