libsepol/backport-libsepol-check-for-overflow-in-put_entry.patch
2023-11-25 10:15:11 +08:00

34 lines
1.1 KiB
Diff

From df666f70534ef225b97899f997b4077aeb285972 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Christian=20G=C3=B6ttsche?= <cgzones@googlemail.com>
Date: Thu, 6 Jul 2023 15:57:18 +0200
Subject: [PATCH] libsepol: check for overflow in put_entry()
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
put_entry() is used during writing binary policies. Avoid short writes
due to an overflow.
Signed-off-by: Christian Göttsche <cgzones@googlemail.com>
Acked-by: James Carter <jwcart2@gmail.com>
---
libsepol/src/services.c | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)
diff --git a/libsepol/src/services.c b/libsepol/src/services.c
index 72772dbd29..6bddc287e1 100644
--- a/libsepol/src/services.c
+++ b/libsepol/src/services.c
@@ -1711,7 +1711,10 @@ int next_entry(void *buf, struct policy_file *fp, size_t bytes)
size_t put_entry(const void *ptr, size_t size, size_t n,
struct policy_file *fp)
{
- size_t bytes = size * n;
+ size_t bytes;
+
+ if (__builtin_mul_overflow(size, n, &bytes))
+ return 0;
switch (fp->type) {
case PF_USE_STDIO: