blob: 03818469f3ccca1f6e1c1739753e2392df8c2408 [file] [log] [blame]
From: Vegard Nossum <vegard.nossum@oracle.com>
Date: Sat, 23 Jul 2016 07:43:50 +0200
Subject: net/irda: fix NULL pointer dereference on memory allocation failure
commit d3e6952cfb7ba5f4bfa29d4803ba91f96ce1204d upstream.
I ran into this:
kasan: CONFIG_KASAN_INLINE enabled
kasan: GPF could be caused by NULL-ptr deref or user memory access
general protection fault: 0000 [#1] PREEMPT SMP KASAN
CPU: 2 PID: 2012 Comm: trinity-c3 Not tainted 4.7.0-rc7+ #19
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Ubuntu-1.8.2-1ubuntu1 04/01/2014
task: ffff8800b745f2c0 ti: ffff880111740000 task.ti: ffff880111740000
RIP: 0010:[<ffffffff82bbf066>] [<ffffffff82bbf066>] irttp_connect_request+0x36/0x710
RSP: 0018:ffff880111747bb8 EFLAGS: 00010286
RAX: dffffc0000000000 RBX: 0000000000000000 RCX: 0000000069dd8358
RDX: 0000000000000009 RSI: 0000000000000027 RDI: 0000000000000048
RBP: ffff880111747c00 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000069dd8358 R11: 1ffffffff0759723 R12: 0000000000000000
R13: ffff88011a7e4780 R14: 0000000000000027 R15: 0000000000000000
FS: 00007fc738404700(0000) GS:ffff88011af00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fc737fdfb10 CR3: 0000000118087000 CR4: 00000000000006e0
Stack:
0000000000000200 ffff880111747bd8 ffffffff810ee611 ffff880119f1f220
ffff880119f1f4f8 ffff880119f1f4f0 ffff88011a7e4780 ffff880119f1f232
ffff880119f1f220 ffff880111747d58 ffffffff82bca542 0000000000000000
Call Trace:
[<ffffffff82bca542>] irda_connect+0x562/0x1190
[<ffffffff825ae582>] SYSC_connect+0x202/0x2a0
[<ffffffff825b4489>] SyS_connect+0x9/0x10
[<ffffffff8100334c>] do_syscall_64+0x19c/0x410
[<ffffffff83295ca5>] entry_SYSCALL64_slow_path+0x25/0x25
Code: 41 89 ca 48 89 e5 41 57 41 56 41 55 41 54 41 89 d7 53 48 89 fb 48 83 c7 48 48 89 fa 41 89 f6 48 c1 ea 03 48 83 ec 20 4c 8b 65 10 <0f> b6 04 02 84 c0 74 08 84 c0 0f 8e 4c 04 00 00 80 7b 48 00 74
RIP [<ffffffff82bbf066>] irttp_connect_request+0x36/0x710
RSP <ffff880111747bb8>
---[ end trace 4cda2588bc055b30 ]---
The problem is that irda_open_tsap() can fail and leave self->tsap = NULL,
and then irttp_connect_request() almost immediately dereferences it.
Signed-off-by: Vegard Nossum <vegard.nossum@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
---
net/irda/af_irda.c | 7 +++++--
1 file changed, 5 insertions(+), 2 deletions(-)
--- a/net/irda/af_irda.c
+++ b/net/irda/af_irda.c
@@ -1037,8 +1037,11 @@ static int irda_connect(struct socket *s
}
/* Check if we have opened a local TSAP */
- if (!self->tsap)
- irda_open_tsap(self, LSAP_ANY, addr->sir_name);
+ if (!self->tsap) {
+ err = irda_open_tsap(self, LSAP_ANY, addr->sir_name);
+ if (err)
+ goto out;
+ }
/* Move to connecting socket, start sending Connect Requests */
sock->state = SS_CONNECTING;