korg/linux
0
0
Fork 0
mirror of https://mirrors.bfsu.edu.cn/git/linux.git synced 2024-11-15 00:04:15 +08:00
Code Issues Packages Projects Releases Wiki Activity

ipv6: Fix signed integer overflow in l2tp_ip6_sendmsg

Browse Source 
[ Upstream commit f638a84afe ]

When len >= INT_MAX - transhdrlen, ulen = len + transhdrlen will be
overflow. To fix, we can follow what udpv6 does and subtract the
transhdrlen from the max.

Signed-off-by: Wang Yufen <wangyufen@huawei.com>
Link: https://lore.kernel.org/r/20220607120028.845916-2-wangyufen@huawei.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
This commit is contained in:
Wang Yufen 2022-06-07 20:00:28 +08:00 committed by Greg Kroah-Hartman
parent f21f908347
commit 0e818d433f
1 changed files with 3 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

5
net/l2tp/l2tp_ip6.c
View File

@ -526,14 +526,15 @@ static int l2tp_ip6_sendmsg(struct sock *sk, struct msghdr *msg, size_t len)
struct ipcm6_cookie ipc6;
int addr_len = msg->msg_namelen;
int transhdrlen = 4; /* zero session-id */
int ulen = len + transhdrlen;
int ulen;
int err;
/* Rough check on arithmetic overflow,
better check is made in ip6_append_data().
*/
if (len > INT_MAX)
if (len > INT_MAX - transhdrlen)
return -EMSGSIZE;
ulen = len + transhdrlen;
/* Mirror BSD error message compatibility */
if (msg->msg_flags & MSG_OOB)