All of lore.kernel.org
 help / color / mirror / Atom feed
* [PATCH] Prevent normalize() from reading into undefined memory
@ 2022-12-04 10:58 Sohom Datta
  2023-01-08 14:12 ` Jiri Olsa
  0 siblings, 1 reply; 3+ messages in thread
From: Sohom Datta @ 2022-12-04 10:58 UTC (permalink / raw)
  To: Peter Zijlstra, Ingo Molnar, Arnaldo Carvalho de Melo,
	Mark Rutland, Alexander Shishkin, Jiri Olsa, Namhyung Kim
  Cc: Sohom Datta, linux-perf-users, linux-kernel

The current implementation does not account for a
trailing backslash followed by a null-byte. If a
null-byte is encountered following a backslash,
normalize() will continue reading (and potentially
writing) into garbage memory ignoring the EOS
null-byte.

Signed-off-by: Sohom Datta <sohomdatta1+git@gmail.com>
---
 tools/perf/util/expr.l | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/tools/perf/util/expr.l b/tools/perf/util/expr.l
index 0168a9637330..d47de5f270a8 100644
--- a/tools/perf/util/expr.l
+++ b/tools/perf/util/expr.l
@@ -42,8 +42,11 @@ static char *normalize(char *str, int runtime)
 	char *dst = str;
 
 	while (*str) {
-		if (*str == '\\')
+		if (*str == '\\') {
 			*dst++ = *++str;
+			if (!*str)
+				break;
+		}
 		else if (*str == '?') {
 			char *paramval;
 			int i = 0;
-- 
2.38.1


^ permalink raw reply related	[flat|nested] 3+ messages in thread

end of thread, other threads:[~2023-01-18 14:03 UTC | newest]

Thread overview: 3+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2022-12-04 10:58 [PATCH] Prevent normalize() from reading into undefined memory Sohom Datta
2023-01-08 14:12 ` Jiri Olsa
     [not found]   ` <CAP-5=fUjto38BaJX+Uj-BUOc74vg5KqZFewVCuUTW81Q=PAXHA@mail.gmail.com>
2023-01-18 13:37     ` Arnaldo Carvalho de Melo

This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.