zziplib/CVE-2020-18770.patch
Jakub Martisko c5d0017ab8 Fix: CVE-2020-18770
Resolves: RHEL-14966
2024-01-26 12:42:00 +01:00

31 lines
1.2 KiB
Diff

From 18c6c043bd7d8f139f30e9c7749013115d5fc5b7 Mon Sep 17 00:00:00 2001
From: Valentin Lefebvre <valentin.lefebvre@suse.com>
Date: Wed, 20 Sep 2023 12:04:56 +0200
Subject: [PATCH] mmappend.c: Avoid invalid access for header entry
* zzip_disk_entry_to_file_header checking the pointer by substraction
instead of addition where it could lead to an invalid access memory.
* CVE-2020-18770
Signed-off-by: Valentin Lefebvre <valentin.lefebvre@suse.com>
---
zzip/mmapped.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)
diff --git a/zzip/mmapped.c b/zzip/mmapped.c
index 2071882..beb094d 100644
--- a/zzip/mmapped.c
+++ b/zzip/mmapped.c
@@ -275,8 +275,9 @@ zzip_disk_entry_to_data(ZZIP_DISK * disk, struct zzip_disk_entry * entry)
struct zzip_file_header *
zzip_disk_entry_to_file_header(ZZIP_DISK * disk, struct zzip_disk_entry *entry)
{
- zzip_byte_t *const ptr = disk->buffer + zzip_disk_entry_fileoffset(entry);
- if (disk->buffer > ptr || ptr >= disk->endbuf)
+ zzip_off_t off = zzip_disk_entry_fileoffset(entry);
+ zzip_byte_t *const ptr = disk->buffer + off;
+ if (disk->buffer > ptr || disk->buffer >= disk->endbuf - off)
{
errno = EBADMSG;
return 0;