vim/backport-CVE-2023-5344.patch
2023-10-11 14:19:34 +08:00

48 lines
1.3 KiB
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From 3bd7fa12e146c6051490d048a4acbfba974eeb04 Mon Sep 17 00:00:00 2001
From: Christian Brabandt <cb@256bit.org>
Date: Mon, 2 Oct 2023 20:59:08 +0200
Subject: [PATCH 2156/2205] patch 9.0.1969: [security] buffer-overflow in
trunc_string()
Problem: buffer-overflow in trunc_string()
Solution: Add NULL at end of buffer
Currently trunc_string() assumes that when the string is too long,
buf[e-1] will always be writeable. But that assumption may not always be
true. The condition currently looks like this
else if (e + 3 < buflen)
[...]
else
{
// can't fit in the "...", just truncate it
buf[e - 1] = NUL;
}
but this means, we may run into the last else clause with e still being
larger than buflen. So a buffer overflow occurs.
So instead of using `buf[e - 1]`, let's just always
truncate at `buf[buflen - 1]` which should always be writable.
Signed-off-by: Christian Brabandt <cb@256bit.org>
---
src/message.c | 2 +-
1 files changed, 1 insertions(+), 1 deletion(-)
diff --git a/src/message.c b/src/message.c
index 2fc6cefa9..83c8b4f4a 100644
--- a/src/message.c
+++ b/src/message.c
@@ -349,7 +349,7 @@ trunc_string(
else
{
// can't fit in the "...", just truncate it
- buf[e - 1] = NUL;
+ buf[buflen - 1] = NUL;
}
}
--
2.27.0