diff mbox series

[net] xfrm6: check ip6_dst_idev() return value in xfrm6_get_saddr()

Message ID 20240615154231.234442-1-edumazet@google.com (mailing list archive)
State Accepted
Commit d46401052c2d5614da8efea5788532f0401cb164
Delegated to: Netdev Maintainers
Headers show
Series [net] xfrm6: check ip6_dst_idev() return value in xfrm6_get_saddr() | expand

Checks

Context Check Description
netdev/series_format success Single patches do not need cover letters
netdev/tree_selection success Clearly marked for net
netdev/ynl success Generated files up to date; no warnings/errors; no diff in generated;
netdev/fixes_present success Fixes tag present in non-next series
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 859 this patch: 859
netdev/build_tools success No tools touched, skip
netdev/cc_maintainers warning 1 maintainers not CCed: herbert@gondor.apana.org.au
netdev/build_clang success Errors and warnings before: 863 this patch: 863
netdev/verify_signedoff success Signed-off-by tag matches author and committer
netdev/deprecated_api success None detected
netdev/check_selftest success No net selftest shell script
netdev/verify_fixes success Fixes tag looks correct
netdev/build_allmodconfig_warn success Errors and warnings before: 863 this patch: 863
netdev/checkpatch warning WARNING: Possible repeated word: 'Google'
netdev/build_clang_rust success No Rust files in patch. Skipping build
netdev/kdoc success Errors and warnings before: 0 this patch: 0
netdev/source_inline success Was 0 now: 0
netdev/contest success net-next-2024-06-16--18-00 (tests: 659)

Commit Message

Eric Dumazet June 15, 2024, 3:42 p.m. UTC 
ip6_dst_idev() can return NULL, xfrm6_get_saddr() must act accordingly.

syzbot reported:

Oops: general protection fault, probably for non-canonical address 0xdffffc0000000000: 0000 [#1] PREEMPT SMP KASAN PTI
KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007]
CPU: 1 PID: 12 Comm: kworker/u8:1 Not tainted 6.10.0-rc2-syzkaller-00383-gb8481381d4e2 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024
Workqueue: wg-kex-wg1 wg_packet_handshake_send_worker
 RIP: 0010:xfrm6_get_saddr+0x93/0x130 net/ipv6/xfrm6_policy.c:64
Code: df 48 89 fa 48 c1 ea 03 80 3c 02 00 0f 85 97 00 00 00 4c 8b ab d8 00 00 00 48 b8 00 00 00 00 00 fc ff df 4c 89 ea 48 c1 ea 03 <80> 3c 02 00 0f 85 86 00 00 00 4d 8b 6d 00 e8 ca 13 47 01 48 b8 00
RSP: 0018:ffffc90000117378 EFLAGS: 00010246
RAX: dffffc0000000000 RBX: ffff88807b079dc0 RCX: ffffffff89a0d6d7
RDX: 0000000000000000 RSI: ffffffff89a0d6e9 RDI: ffff88807b079e98
RBP: ffff88807ad73248 R08: 0000000000000007 R09: fffffffffffff000
R10: ffff88807b079dc0 R11: 0000000000000007 R12: ffffc90000117480
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff8880b9300000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f4586d00440 CR3: 0000000079042000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
  xfrm_get_saddr net/xfrm/xfrm_policy.c:2452 [inline]
  xfrm_tmpl_resolve_one net/xfrm/xfrm_policy.c:2481 [inline]
  xfrm_tmpl_resolve+0xa26/0xf10 net/xfrm/xfrm_policy.c:2541
  xfrm_resolve_and_create_bundle+0x140/0x2570 net/xfrm/xfrm_policy.c:2835
  xfrm_bundle_lookup net/xfrm/xfrm_policy.c:3070 [inline]
  xfrm_lookup_with_ifid+0x4d1/0x1e60 net/xfrm/xfrm_policy.c:3201
  xfrm_lookup net/xfrm/xfrm_policy.c:3298 [inline]
  xfrm_lookup_route+0x3b/0x200 net/xfrm/xfrm_policy.c:3309
  ip6_dst_lookup_flow+0x15c/0x1d0 net/ipv6/ip6_output.c:1256
  send6+0x611/0xd20 drivers/net/wireguard/socket.c:139
  wg_socket_send_skb_to_peer+0xf9/0x220 drivers/net/wireguard/socket.c:178
  wg_socket_send_buffer_to_peer+0x12b/0x190 drivers/net/wireguard/socket.c:200
  wg_packet_send_handshake_initiation+0x227/0x360 drivers/net/wireguard/send.c:40
  wg_packet_handshake_send_worker+0x1c/0x30 drivers/net/wireguard/send.c:51
  process_one_work+0x9fb/0x1b60 kernel/workqueue.c:3231
  process_scheduled_works kernel/workqueue.c:3312 [inline]
  worker_thread+0x6c8/0xf70 kernel/workqueue.c:3393
  kthread+0x2c1/0x3a0 kernel/kthread.c:389
  ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
  ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
---
 net/ipv6/xfrm6_policy.c | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

Comments

David Ahern June 16, 2024, 6:26 p.m. UTC | #1 
On 6/15/24 9:42 AM, Eric Dumazet wrote:
> ip6_dst_idev() can return NULL, xfrm6_get_saddr() must act accordingly.
> 
> syzbot reported:
> 

...

> 
> Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
> Reported-by: syzbot <syzkaller@googlegroups.com>
> Signed-off-by: Eric Dumazet <edumazet@google.com>
> ---
>  net/ipv6/xfrm6_policy.c | 8 +++++++-
>  1 file changed, 7 insertions(+), 1 deletion(-)
> 

Reviewed-by: David Ahern <dsahern@kernel.org>
patchwork-bot+netdevbpf@kernel.org June 18, 2024, 1:10 a.m. UTC | #2 
Hello:

This patch was applied to netdev/net.git (main)
by Jakub Kicinski <kuba@kernel.org>:

On Sat, 15 Jun 2024 15:42:31 +0000 you wrote:
> ip6_dst_idev() can return NULL, xfrm6_get_saddr() must act accordingly.
> 
> syzbot reported:
> 
> Oops: general protection fault, probably for non-canonical address 0xdffffc0000000000: 0000 [#1] PREEMPT SMP KASAN PTI
> KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007]
> CPU: 1 PID: 12 Comm: kworker/u8:1 Not tainted 6.10.0-rc2-syzkaller-00383-gb8481381d4e2 #0
> Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024
> Workqueue: wg-kex-wg1 wg_packet_handshake_send_worker
>  RIP: 0010:xfrm6_get_saddr+0x93/0x130 net/ipv6/xfrm6_policy.c:64
> Code: df 48 89 fa 48 c1 ea 03 80 3c 02 00 0f 85 97 00 00 00 4c 8b ab d8 00 00 00 48 b8 00 00 00 00 00 fc ff df 4c 89 ea 48 c1 ea 03 <80> 3c 02 00 0f 85 86 00 00 00 4d 8b 6d 00 e8 ca 13 47 01 48 b8 00
> RSP: 0018:ffffc90000117378 EFLAGS: 00010246
> RAX: dffffc0000000000 RBX: ffff88807b079dc0 RCX: ffffffff89a0d6d7
> RDX: 0000000000000000 RSI: ffffffff89a0d6e9 RDI: ffff88807b079e98
> RBP: ffff88807ad73248 R08: 0000000000000007 R09: fffffffffffff000
> R10: ffff88807b079dc0 R11: 0000000000000007 R12: ffffc90000117480
> R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
> FS:  0000000000000000(0000) GS:ffff8880b9300000(0000) knlGS:0000000000000000
> CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
> CR2: 00007f4586d00440 CR3: 0000000079042000 CR4: 00000000003506f0
> DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
> DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
> Call Trace:
>  <TASK>
>   xfrm_get_saddr net/xfrm/xfrm_policy.c:2452 [inline]
>   xfrm_tmpl_resolve_one net/xfrm/xfrm_policy.c:2481 [inline]
>   xfrm_tmpl_resolve+0xa26/0xf10 net/xfrm/xfrm_policy.c:2541
>   xfrm_resolve_and_create_bundle+0x140/0x2570 net/xfrm/xfrm_policy.c:2835
>   xfrm_bundle_lookup net/xfrm/xfrm_policy.c:3070 [inline]
>   xfrm_lookup_with_ifid+0x4d1/0x1e60 net/xfrm/xfrm_policy.c:3201
>   xfrm_lookup net/xfrm/xfrm_policy.c:3298 [inline]
>   xfrm_lookup_route+0x3b/0x200 net/xfrm/xfrm_policy.c:3309
>   ip6_dst_lookup_flow+0x15c/0x1d0 net/ipv6/ip6_output.c:1256
>   send6+0x611/0xd20 drivers/net/wireguard/socket.c:139
>   wg_socket_send_skb_to_peer+0xf9/0x220 drivers/net/wireguard/socket.c:178
>   wg_socket_send_buffer_to_peer+0x12b/0x190 drivers/net/wireguard/socket.c:200
>   wg_packet_send_handshake_initiation+0x227/0x360 drivers/net/wireguard/send.c:40
>   wg_packet_handshake_send_worker+0x1c/0x30 drivers/net/wireguard/send.c:51
>   process_one_work+0x9fb/0x1b60 kernel/workqueue.c:3231
>   process_scheduled_works kernel/workqueue.c:3312 [inline]
>   worker_thread+0x6c8/0xf70 kernel/workqueue.c:3393
>   kthread+0x2c1/0x3a0 kernel/kthread.c:389
>   ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
>   ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
> 
> [...]

Here is the summary with links:
  - [net] xfrm6: check ip6_dst_idev() return value in xfrm6_get_saddr()
    https://git.kernel.org/netdev/net/c/d46401052c2d

You are awesome, thank you!
diff mbox series

Patch

diff --git a/net/ipv6/xfrm6_policy.c b/net/ipv6/xfrm6_policy.c
index cc885d3aa9e5947b0f087d599c97a020ba6fe385..2f1ea5f999a259a96693566d3e776a1391b70c57 100644
--- a/net/ipv6/xfrm6_policy.c
+++ b/net/ipv6/xfrm6_policy.c
@@ -56,12 +56,18 @@  static int xfrm6_get_saddr(struct net *net, int oif,
 {
 	struct dst_entry *dst;
 	struct net_device *dev;
+	struct inet6_dev *idev;
 
 	dst = xfrm6_dst_lookup(net, 0, oif, NULL, daddr, mark);
 	if (IS_ERR(dst))
 		return -EHOSTUNREACH;
 
-	dev = ip6_dst_idev(dst)->dev;
+	idev = ip6_dst_idev(dst);
+	if (!idev) {
+		dst_release(dst);
+		return -EHOSTUNREACH;
+	}
+	dev = idev->dev;
 	ipv6_dev_get_saddr(dev_net(dev), dev, &daddr->in6, 0, &saddr->in6);
 	dst_release(dst);
 	return 0;