From 536a16fef0f84b71d949c67b0fc51de6325bca32 Mon Sep 17 00:00:00 2001 From: Arjan van de Ven Date: Wed, 30 Sep 2009 13:51:11 +0200 Subject: [PATCH] net ax25: Fix signed comparison in the sockopt handler fixed upstream in commit b7058842c940ad2c08dd829b21e5c92ebe3b8758 in a different way The ax25 code tried to use if (optlen < sizeof(int)) return -EINVAL; as a security check against optlen being negative (or zero) in the set socket option. Unfortunately, "sizeof(int)" is an unsigned property, with the result that the whole comparison is done in unsigned, letting negative values slip through. This patch changes this to if (optlen < (int)sizeof(int)) return -EINVAL; so that the comparison is done as signed, and negative values get properly caught. Signed-off-by: Arjan van de Ven Cc: David S. Miller Cc: Ingo Molnar Cc: Linus Torvalds Signed-off-by: Greg Kroah-Hartman --- net/ax25/af_ax25.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/net/ax25/af_ax25.c b/net/ax25/af_ax25.c index da0f64f82b57..f03529cabcb0 100644 --- a/net/ax25/af_ax25.c +++ b/net/ax25/af_ax25.c @@ -538,7 +538,7 @@ static int ax25_setsockopt(struct socket *sock, int level, int optname, if (level != SOL_AX25) return -ENOPROTOOPT; - if (optlen < sizeof(int)) + if (optlen < (int)sizeof(int)) return -EINVAL; if (get_user(opt, (int __user *)optval)) -- 2.39.5