netdev - [patch] RDS: fix an integer overflow check

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Date:	Fri, 12 Oct 2012 10:31:46 +0300
From:	Dan Carpenter <dan.carpenter@...cle.com>
To:	Venkat Venkatsubra <venkat.x.venkatsubra@...cle.com>
Cc:	"David S. Miller" <davem@...emloft.net>, rds-devel@....oracle.com,
	netdev@...r.kernel.org, kernel-janitors@...r.kernel.org
Subject: [patch] RDS: fix an integer overflow check

"len" is an int.  We verified that len was postive already.  Since
PAGE_SIZE is specified as an unsigned long, the type it promoted to
unsigned and the condition is never true.

I'm not sure this check is actually needed.  It might be that we could
just remove it?

Signed-off-by: Dan Carpenter <dan.carpenter@...cle.com>

diff --git a/net/rds/info.c b/net/rds/info.c
index 9a6b4f6..4d62618 100644
--- a/net/rds/info.c
+++ b/net/rds/info.c
@@ -176,7 +176,7 @@ int rds_info_getsockopt(struct socket *sock, int optname, char __user *optval,
 
 	/* check for all kinds of wrapping and the like */
 	start = (unsigned long)optval;
-	if (len < 0 || len + PAGE_SIZE - 1 < len || start + len < start) {
+	if (len < 0 || len > INT_MAX - (PAGE_SIZE - 1) || start + len < start) {
 		ret = -EINVAL;
 		goto out;
 	}
--
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html