netdev.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
* [PATCH net-next] rtnetlink: Fix null-ptr-deref in rtnl_newlink
@ 2018-06-01  8:16 Prashant Bhole
  2018-06-01  8:26 ` Eric Dumazet
                   ` (2 more replies)
  0 siblings, 3 replies; 5+ messages in thread
From: Prashant Bhole @ 2018-06-01  8:16 UTC (permalink / raw)
  To: David S . Miller, Eric Dumazet
  Cc: Prashant Bhole, Daniel Borkmann, Alexei Starovoitov, Kirill Tkhai,
	Florian Westphal, netdev

In rtnl_newlink(), NULL check is performed on m_ops however member of
ops is accessed. Fixed by accessing member of m_ops instead of ops.

[  345.432629] BUG: KASAN: null-ptr-deref in rtnl_newlink+0x400/0x1110
[  345.432629] Read of size 4 at addr 0000000000000088 by task ip/986
[  345.432629]
[  345.432629] CPU: 1 PID: 986 Comm: ip Not tainted 4.17.0-rc6+ #9
[  345.432629] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1ubuntu1 04/01/2014
[  345.432629] Call Trace:
[  345.432629]  dump_stack+0xc6/0x150
[  345.432629]  ? dump_stack_print_info.cold.0+0x1b/0x1b
[  345.432629]  ? kasan_report+0xb4/0x410
[  345.432629]  kasan_report.cold.4+0x8f/0x91
[  345.432629]  ? rtnl_newlink+0x400/0x1110
[  345.432629]  rtnl_newlink+0x400/0x1110
[...]

Fixes: ccf8dbcd062a ("rtnetlink: Remove VLA usage")
Signed-off-by: Prashant Bhole <bhole_prashant_q7@lab.ntt.co.jp>
---
 net/core/rtnetlink.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c
index 8ca49a0e13fb..9a1ba2015ad8 100644
--- a/net/core/rtnetlink.c
+++ b/net/core/rtnetlink.c
@@ -2936,7 +2936,7 @@ static int rtnl_newlink(struct sk_buff *skb, struct nlmsghdr *nlh,
 		}
 
 		if (m_ops) {
-			if (ops->slave_maxtype > RTNL_SLAVE_MAX_TYPE)
+			if (m_ops->slave_maxtype > RTNL_SLAVE_MAX_TYPE)
 				return -EINVAL;
 
 			if (m_ops->slave_maxtype &&
-- 
2.17.0

^ permalink raw reply related	[flat|nested] 5+ messages in thread

end of thread, other threads:[~2018-06-01 22:13 UTC | newest]

Thread overview: 5+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2018-06-01  8:16 [PATCH net-next] rtnetlink: Fix null-ptr-deref in rtnl_newlink Prashant Bhole
2018-06-01  8:26 ` Eric Dumazet
2018-06-01 22:13   ` Kees Cook
2018-06-01 13:03 ` Ido Schimmel
2018-06-01 14:39 ` David Miller

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).