From 7d5b51a14e90dd6a402a954d0dbd3f70d0f33367 Mon Sep 17 00:00:00 2001 From: Gavrilov Ilia Date: Thu, 7 Mar 2024 14:23:50 +0000 Subject: [PATCH] net: kcm: fix incorrect parameter validation in the kcm_getsockopt) function BugLink: https://bugs.launchpad.net/bugs/2060097 [ Upstream commit 3ed5f415133f9b7518fbe55ba9ae9a3f5e700929 ] 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: ab7ac4eb9832 ("kcm: Kernel Connection Multiplexor module") Signed-off-by: Gavrilov Ilia Signed-off-by: David S. Miller Signed-off-by: Sasha Levin (cherry picked from commit 8b409c7cf3600ef3307fcde582d925fd1a6a76e8) Signed-off-by: Paolo Pisati --- net/kcm/kcmsock.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/net/kcm/kcmsock.c b/net/kcm/kcmsock.c index 1184d40167b8..eda933c09792 100644 --- a/net/kcm/kcmsock.c +++ b/net/kcm/kcmsock.c @@ -1152,10 +1152,11 @@ static int kcm_getsockopt(struct socket *sock, int level, int optname, if (get_user(len, optlen)) 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 KCM_RECV_DISABLE: val = kcm->rx_disabled;