From: Gavrilov Ilia Ilia.Gavrilov@infotecs.ru
[ Upstream commit 4bb3ba7b74fceec6f558745b25a43c6521cf5506 ]
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") Reviewed-by: Willem de Bruijn willemb@google.com Signed-off-by: Gavrilov Ilia Ilia.Gavrilov@infotecs.ru Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Sasha Levin sashal@kernel.org --- net/ipv4/udp.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c index 476f79f1563a8..b2541c7d7c87f 100644 --- a/net/ipv4/udp.c +++ b/net/ipv4/udp.c @@ -2748,11 +2748,11 @@ int udp_lib_getsockopt(struct sock *sk, 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 UDP_CORK: val = READ_ONCE(up->corkflag);