This is a note to let you know that I've just added the patch titled tcp: fix incorrect parameter validation in the do_tcp_getsockopt() function to the 6.1-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: tcp-fix-incorrect-parameter-validation-in-the-do_tcp.patch and it can be found in the queue-6.1 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit b8d28ee354fd93c2a7e11ba9beb89f648dd95952 Author: Gavrilov Ilia <Ilia.Gavrilov@xxxxxxxxxxx> Date: Thu Mar 7 14:23:49 2024 +0000 tcp: fix incorrect parameter validation in the do_tcp_getsockopt() function [ Upstream commit 716edc9706deb3bb2ff56e2eeb83559cea8f22db ] The 'len' variable can't be negative when assigned the result of 'min_t' because all 'min_t' parameters are cast to unsigned int, and then the minimum one is chosen. To fix the logic, check 'len' as read from 'optlen', where the types of relevant variables are (signed) int. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Gavrilov Ilia <Ilia.Gavrilov@xxxxxxxxxxx> Reviewed-by: Jason Xing <kerneljasonxing@xxxxxxxxx> Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c index 86e7695d91adf..5a165e29f7be4 100644 --- a/net/ipv4/tcp.c +++ b/net/ipv4/tcp.c @@ -4102,11 +4102,11 @@ int do_tcp_getsockopt(struct sock *sk, int level, if (copy_from_sockptr(&len, optlen, sizeof(int))) return -EFAULT; - len = min_t(unsigned int, len, sizeof(int)); - if (len < 0) return -EINVAL; + len = min_t(unsigned int, len, sizeof(int)); + switch (optname) { case TCP_MAXSEG: val = tp->mss_cache;