unzip/backport-CVE-2021-4217.patch
2022-09-06 11:08:07 +08:00

40 lines
1.3 KiB
Diff

From 731d698377dbd1f5b1b90efeb8094602ed59fc40 Mon Sep 17 00:00:00 2001
From: Nils Bars <nils.bars@t-online.de>
Date: Mon, 17 Jan 2022 16:53:16 +0000
Subject: [PATCH] Fix null pointer dereference and use of uninitialized data
This fixes a bug that causes use of uninitialized heap data if `readbuf` fails
to read as many bytes as indicated by the extra field length attribute.
Furthermore, this fixes a null pointer dereference if an archive contains an
`EF_UNIPATH` extra field but does not have a filename set.
Reference:https://bugs.launchpad.net/ubuntu/+source/unzip/+bug/1957077
Conflict: fileio.c file not change.
---
process.c | 6 +++++-
1 file changed, 5 insertions(+), 1 deletion(-)
diff --git a/process.c b/process.c
index abe938b..f573ee4 100644
--- a/process.c
+++ b/process.c
@@ -2060,10 +2060,14 @@ int getUnicodeData(__G__ ef_buf, ef_len)
G.unipath_checksum = makelong(offset + ef_buf);
offset += 4;
+ if (!G.filename_full) {
+ /* Check if we have a unicode extra section but no filename set */
+ return PK_ERR;
+ }
+
/*
* Compute 32-bit crc
*/
-
chksum = crc32(chksum, (uch *)(G.filename_full),
strlen(G.filename_full));
--
2.33.0