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Subject[PATCH] Prevent normalize() from reading into undefined memory
Date
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
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