netdev - [patch] irda: precedence bug in irlmp_seq_hb

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:	Mon, 19 Oct 2015 13:16:49 +0300
From:	Dan Carpenter <dan.carpenter@...cle.com>
To:	Samuel Ortiz <samuel@...tiz.org>
Cc:	"David S. Miller" <davem@...emloft.net>, netdev@...r.kernel.org,
	security@...nel.org, throber3 <throber3@...il.com>,
	程君(成淼) <chengmiao.cj@...baba-inc.com>
Subject: [patch] irda: precedence bug in irlmp_seq_hb_idx()

This is decrementing the pointer, instead of the value stored in the
pointer.  KASan detects it as an out of bounds reference.

Reported-by: "Berry Cheng 程君(成淼)" <chengmiao.cj@...baba-inc.com>
Signed-off-by: Dan Carpenter <dan.carpenter@...cle.com>
---
This bug predates the start of git.  You would think it would have been
reported earlier since it looks like a serious bug.  I cannot test this
so please review carefully.

diff --git a/net/irda/irlmp.c b/net/irda/irlmp.c
index a26c401..4396459 100644
--- a/net/irda/irlmp.c
+++ b/net/irda/irlmp.c
@@ -1839,7 +1839,7 @@ static void *irlmp_seq_hb_idx(struct irlmp_iter_state *iter, loff_t *off)
 	for (element = hashbin_get_first(iter->hashbin);
 	     element != NULL;
 	     element = hashbin_get_next(iter->hashbin)) {
-		if (!off || *off-- == 0) {
+		if (!off || (*off)-- == 0) {
 			/* NB: hashbin left locked */
 			return element;
 		}
--
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