linux-kernel - [PATCH AUTOSEL 5.15 4/9] udf: udftime: prevent overflow in udf_disk_stamp_to

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20240605115415.2964165-4-sashal@kernel.org>
Date: Wed,  5 Jun 2024 07:54:02 -0400
From: Sasha Levin <sashal@...nel.org>
To: linux-kernel@...r.kernel.org,
	stable@...r.kernel.org
Cc: Roman Smirnov <r.smirnov@....ru>,
	Jan Kara <jack@...e.cz>,
	Sergey Shtylyov <s.shtylyov@....ru>,
	Sasha Levin <sashal@...nel.org>,
	jack@...e.com
Subject: [PATCH AUTOSEL 5.15 4/9] udf: udftime: prevent overflow in udf_disk_stamp_to_time()

From: Roman Smirnov <r.smirnov@....ru>

[ Upstream commit 3b84adf460381169c085e4bc09e7b57e9e16db0a ]

An overflow can occur in a situation where src.centiseconds
takes the value of 255. This situation is unlikely, but there
is no validation check anywere in the code.

Found by Linux Verification Center (linuxtesting.org) with Svace.

Suggested-by: Jan Kara <jack@...e.cz>
Signed-off-by: Roman Smirnov <r.smirnov@....ru>
Reviewed-by: Sergey Shtylyov <s.shtylyov@....ru>
Signed-off-by: Jan Kara <jack@...e.cz>
Message-Id: <20240327132755.13945-1-r.smirnov@....ru>
Signed-off-by: Sasha Levin <sashal@...nel.org>
---
 fs/udf/udftime.c | 11 ++++++++---
 1 file changed, 8 insertions(+), 3 deletions(-)

diff --git a/fs/udf/udftime.c b/fs/udf/udftime.c
index fce4ad976c8c2..26169b1f482c3 100644
--- a/fs/udf/udftime.c
+++ b/fs/udf/udftime.c
@@ -60,13 +60,18 @@ udf_disk_stamp_to_time(struct timespec64 *dest, struct timestamp src)
 	dest->tv_sec = mktime64(year, src.month, src.day, src.hour, src.minute,
 			src.second);
 	dest->tv_sec -= offset * 60;
-	dest->tv_nsec = 1000 * (src.centiseconds * 10000 +
-			src.hundredsOfMicroseconds * 100 + src.microseconds);
+
 	/*
 	 * Sanitize nanosecond field since reportedly some filesystems are
 	 * recorded with bogus sub-second values.
 	 */
-	dest->tv_nsec %= NSEC_PER_SEC;
+	if (src.centiseconds < 100 && src.hundredsOfMicroseconds < 100 &&
+	    src.microseconds < 100) {
+		dest->tv_nsec = 1000 * (src.centiseconds * 10000 +
+			src.hundredsOfMicroseconds * 100 + src.microseconds);
+	} else {
+		dest->tv_nsec = 0;
+	}
 }
 
 void
-- 
2.43.0