perf annotate: Prevent overflow in size calculation

A large enough symbol size causes an overflow in the size parameter to
the histogram allocation, leading to a segfault in
symbol__inc_addr_samples later on when this histogram is accessed.

In the case of being called via perf-report, this returns back and
gracefully ignores the sample, eventually ignoring the chained return
value of perf_session_deliver_event in flush_sample_queue.

Signed-off-by: Cody Schafer <cody@linux.vnet.ibm.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Link: http://lkml.kernel.org/r/1342753525-4521-1-git-send-email-cody@linux.vnet.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This commit is contained in:
Cody Schafer 2012-07-19 20:05:25 -07:00 committed by Arnaldo Carvalho de Melo
parent 52f18a2ff9
commit 8696329b7b
1 changed files with 12 additions and 1 deletions

View File

@ -426,7 +426,18 @@ int symbol__alloc_hist(struct symbol *sym)
{
struct annotation *notes = symbol__annotation(sym);
const size_t size = symbol__size(sym);
size_t sizeof_sym_hist = (sizeof(struct sym_hist) + size * sizeof(u64));
size_t sizeof_sym_hist;
/* Check for overflow when calculating sizeof_sym_hist */
if (size > (SIZE_MAX - sizeof(struct sym_hist)) / sizeof(u64))
return -1;
sizeof_sym_hist = (sizeof(struct sym_hist) + size * sizeof(u64));
/* Check for overflow in zalloc argument */
if (sizeof_sym_hist > (SIZE_MAX - sizeof(*notes->src))
/ symbol_conf.nr_events)
return -1;
notes->src = zalloc(sizeof(*notes->src) + symbol_conf.nr_events * sizeof_sym_hist);
if (notes->src == NULL)