diff mbox series

[net] ipvlan: Dont Use skb->sk in ipvlan_process_v{4,6}_outbound

Message ID 20240525034231.2498827-1-yuehaibing@huawei.com (mailing list archive)
State Superseded
Delegated to: Netdev Maintainers
Headers show
Series [net] ipvlan: Dont Use skb->sk in ipvlan_process_v{4,6}_outbound | expand

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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 fail Errors and warnings before: 46 this patch: 46
netdev/build_tools success No tools touched, skip
netdev/cc_maintainers success CCed 5 of 5 maintainers
netdev/build_clang fail Errors and warnings before: 36 this patch: 36
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 fail Errors and warnings before: 46 this patch: 46
netdev/checkpatch success total: 0 errors, 0 warnings, 0 checks, 16 lines checked
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

Commit Message

Yue Haibing May 25, 2024, 3:42 a.m. UTC 
Raw packet from PF_PACKET socket ontop of an IPv6-backed ipvlan device will
hit WARN_ON_ONCE() in sk_mc_loop() through sch_direct_xmit() path.

WARNING: CPU: 2 PID: 0 at net/core/sock.c:775 sk_mc_loop+0x2d/0x70
Modules linked in: sch_netem ipvlan rfkill cirrus drm_shmem_helper sg drm_kms_helper
CPU: 2 PID: 0 Comm: swapper/2 Kdump: loaded Not tainted 6.9.0+ #279
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.15.0-1 04/01/2014
RIP: 0010:sk_mc_loop+0x2d/0x70
Code: fa 0f 1f 44 00 00 65 0f b7 15 f7 96 a3 4f 31 c0 66 85 d2 75 26 48 85 ff 74 1c
RSP: 0018:ffffa9584015cd78 EFLAGS: 00010212
RAX: 0000000000000011 RBX: ffff91e585793e00 RCX: 0000000002c6a001
RDX: 0000000000000000 RSI: 0000000000000040 RDI: ffff91e589c0f000
RBP: ffff91e5855bd100 R08: 0000000000000000 R09: 3d00545216f43d00
R10: ffff91e584fdcc50 R11: 00000060dd8616f4 R12: ffff91e58132d000
R13: ffff91e584fdcc68 R14: ffff91e5869ce800 R15: ffff91e589c0f000
FS:  0000000000000000(0000) GS:ffff91e898100000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f788f7c44c0 CR3: 0000000008e1a000 CR4: 00000000000006f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<IRQ>
 ? __warn (kernel/panic.c:693)
 ? sk_mc_loop (net/core/sock.c:760)
 ? report_bug (lib/bug.c:201 lib/bug.c:219)
 ? handle_bug (arch/x86/kernel/traps.c:239)
 ? exc_invalid_op (arch/x86/kernel/traps.c:260 (discriminator 1))
 ? asm_exc_invalid_op (./arch/x86/include/asm/idtentry.h:621)
 ? sk_mc_loop (net/core/sock.c:760)
 ip6_finish_output2 (net/ipv6/ip6_output.c:83 (discriminator 1))
 ? nf_hook_slow (net/netfilter/core.c:626)
 ip6_finish_output (net/ipv6/ip6_output.c:222)
 ? __pfx_ip6_finish_output (net/ipv6/ip6_output.c:215)
 ipvlan_xmit_mode_l3 (drivers/net/ipvlan/ipvlan_core.c:602) ipvlan
 ipvlan_start_xmit (drivers/net/ipvlan/ipvlan_main.c:226) ipvlan
 dev_hard_start_xmit (net/core/dev.c:3594)
 sch_direct_xmit (net/sched/sch_generic.c:343)
 __qdisc_run (net/sched/sch_generic.c:416)
 net_tx_action (net/core/dev.c:5286)
 handle_softirqs (kernel/softirq.c:555)
 __irq_exit_rcu (kernel/softirq.c:589)
 sysvec_apic_timer_interrupt (arch/x86/kernel/apic/apic.c:1043)

The warning triggers as this:
packet_sendmsg
   packet_snd //skb->sk is packet sk
      __dev_queue_xmit
         __dev_xmit_skb //q->enqueue is not NULL
             __qdisc_run
               sch_direct_xmit
                 dev_hard_start_xmit
                   ipvlan_start_xmit
                      ipvlan_xmit_mode_l3 //l3 mode
                        ipvlan_process_outbound //vepa flag
                          ipvlan_process_v6_outbound
                            ip6_local_out
                                __ip6_finish_output
                                  ip6_finish_output2 //multicast packet
                                    sk_mc_loop //sk->sk_family is AF_PACKET

Call ip{6}_local_out() with NULL sk in ipvlan as other tunnels to fix this.

Fixes: f60e5990d9c1 ("ipv6: protect skb->sk accesses from recursive dereference inside the stack")
Suggested-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Yue Haibing <yuehaibing@huawei.com>
---
 drivers/net/ipvlan/ipvlan_core.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

Comments

Paolo Abeni May 28, 2024, 11:15 a.m. UTC | #1 
On Sat, 2024-05-25 at 11:42 +0800, Yue Haibing wrote:
> Raw packet from PF_PACKET socket ontop of an IPv6-backed ipvlan device will
> hit WARN_ON_ONCE() in sk_mc_loop() through sch_direct_xmit() path.
> 
> WARNING: CPU: 2 PID: 0 at net/core/sock.c:775 sk_mc_loop+0x2d/0x70
> Modules linked in: sch_netem ipvlan rfkill cirrus drm_shmem_helper sg drm_kms_helper
> CPU: 2 PID: 0 Comm: swapper/2 Kdump: loaded Not tainted 6.9.0+ #279
> Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.15.0-1 04/01/2014
> RIP: 0010:sk_mc_loop+0x2d/0x70
> Code: fa 0f 1f 44 00 00 65 0f b7 15 f7 96 a3 4f 31 c0 66 85 d2 75 26 48 85 ff 74 1c
> RSP: 0018:ffffa9584015cd78 EFLAGS: 00010212
> RAX: 0000000000000011 RBX: ffff91e585793e00 RCX: 0000000002c6a001
> RDX: 0000000000000000 RSI: 0000000000000040 RDI: ffff91e589c0f000
> RBP: ffff91e5855bd100 R08: 0000000000000000 R09: 3d00545216f43d00
> R10: ffff91e584fdcc50 R11: 00000060dd8616f4 R12: ffff91e58132d000
> R13: ffff91e584fdcc68 R14: ffff91e5869ce800 R15: ffff91e589c0f000
> FS:  0000000000000000(0000) GS:ffff91e898100000(0000) knlGS:0000000000000000
> CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
> CR2: 00007f788f7c44c0 CR3: 0000000008e1a000 CR4: 00000000000006f0
> DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
> DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
> Call Trace:
> <IRQ>
>  ? __warn (kernel/panic.c:693)
>  ? sk_mc_loop (net/core/sock.c:760)
>  ? report_bug (lib/bug.c:201 lib/bug.c:219)
>  ? handle_bug (arch/x86/kernel/traps.c:239)
>  ? exc_invalid_op (arch/x86/kernel/traps.c:260 (discriminator 1))
>  ? asm_exc_invalid_op (./arch/x86/include/asm/idtentry.h:621)
>  ? sk_mc_loop (net/core/sock.c:760)
>  ip6_finish_output2 (net/ipv6/ip6_output.c:83 (discriminator 1))
>  ? nf_hook_slow (net/netfilter/core.c:626)
>  ip6_finish_output (net/ipv6/ip6_output.c:222)
>  ? __pfx_ip6_finish_output (net/ipv6/ip6_output.c:215)
>  ipvlan_xmit_mode_l3 (drivers/net/ipvlan/ipvlan_core.c:602) ipvlan
>  ipvlan_start_xmit (drivers/net/ipvlan/ipvlan_main.c:226) ipvlan
>  dev_hard_start_xmit (net/core/dev.c:3594)
>  sch_direct_xmit (net/sched/sch_generic.c:343)
>  __qdisc_run (net/sched/sch_generic.c:416)
>  net_tx_action (net/core/dev.c:5286)
>  handle_softirqs (kernel/softirq.c:555)
>  __irq_exit_rcu (kernel/softirq.c:589)
>  sysvec_apic_timer_interrupt (arch/x86/kernel/apic/apic.c:1043)
> 
> The warning triggers as this:
> packet_sendmsg
>    packet_snd //skb->sk is packet sk
>       __dev_queue_xmit
>          __dev_xmit_skb //q->enqueue is not NULL
>              __qdisc_run
>                sch_direct_xmit
>                  dev_hard_start_xmit
>                    ipvlan_start_xmit
>                       ipvlan_xmit_mode_l3 //l3 mode
>                         ipvlan_process_outbound //vepa flag
>                           ipvlan_process_v6_outbound
>                             ip6_local_out
>                                 __ip6_finish_output
>                                   ip6_finish_output2 //multicast packet
>                                     sk_mc_loop //sk->sk_family is AF_PACKET
> 
> Call ip{6}_local_out() with NULL sk in ipvlan as other tunnels to fix this.
> 
> Fixes: f60e5990d9c1 ("ipv6: protect skb->sk accesses from recursive dereference inside the stack")

The patch LGTM, but the above fixes tag looks incorrect, I think the
reproducer should splat even before such commit as the relevant warning
will be still there and should be still reachable.

Cheers,

Paolo
Yue Haibing May 29, 2024, 1:36 a.m. UTC | #2 
On 2024/5/28 19:15, Paolo Abeni wrote:
> On Sat, 2024-05-25 at 11:42 +0800, Yue Haibing wrote:
>> Raw packet from PF_PACKET socket ontop of an IPv6-backed ipvlan device will
>> hit WARN_ON_ONCE() in sk_mc_loop() through sch_direct_xmit() path.
>>
>> WARNING: CPU: 2 PID: 0 at net/core/sock.c:775 sk_mc_loop+0x2d/0x70
>> Modules linked in: sch_netem ipvlan rfkill cirrus drm_shmem_helper sg drm_kms_helper
>> CPU: 2 PID: 0 Comm: swapper/2 Kdump: loaded Not tainted 6.9.0+ #279
>> Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.15.0-1 04/01/2014
>> RIP: 0010:sk_mc_loop+0x2d/0x70
>> Code: fa 0f 1f 44 00 00 65 0f b7 15 f7 96 a3 4f 31 c0 66 85 d2 75 26 48 85 ff 74 1c
>> RSP: 0018:ffffa9584015cd78 EFLAGS: 00010212
>> RAX: 0000000000000011 RBX: ffff91e585793e00 RCX: 0000000002c6a001
>> RDX: 0000000000000000 RSI: 0000000000000040 RDI: ffff91e589c0f000
>> RBP: ffff91e5855bd100 R08: 0000000000000000 R09: 3d00545216f43d00
>> R10: ffff91e584fdcc50 R11: 00000060dd8616f4 R12: ffff91e58132d000
>> R13: ffff91e584fdcc68 R14: ffff91e5869ce800 R15: ffff91e589c0f000
>> FS:  0000000000000000(0000) GS:ffff91e898100000(0000) knlGS:0000000000000000
>> CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
>> CR2: 00007f788f7c44c0 CR3: 0000000008e1a000 CR4: 00000000000006f0
>> DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
>> DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
>> Call Trace:
>> <IRQ>
>>  ? __warn (kernel/panic.c:693)
>>  ? sk_mc_loop (net/core/sock.c:760)
>>  ? report_bug (lib/bug.c:201 lib/bug.c:219)
>>  ? handle_bug (arch/x86/kernel/traps.c:239)
>>  ? exc_invalid_op (arch/x86/kernel/traps.c:260 (discriminator 1))
>>  ? asm_exc_invalid_op (./arch/x86/include/asm/idtentry.h:621)
>>  ? sk_mc_loop (net/core/sock.c:760)
>>  ip6_finish_output2 (net/ipv6/ip6_output.c:83 (discriminator 1))
>>  ? nf_hook_slow (net/netfilter/core.c:626)
>>  ip6_finish_output (net/ipv6/ip6_output.c:222)
>>  ? __pfx_ip6_finish_output (net/ipv6/ip6_output.c:215)
>>  ipvlan_xmit_mode_l3 (drivers/net/ipvlan/ipvlan_core.c:602) ipvlan
>>  ipvlan_start_xmit (drivers/net/ipvlan/ipvlan_main.c:226) ipvlan
>>  dev_hard_start_xmit (net/core/dev.c:3594)
>>  sch_direct_xmit (net/sched/sch_generic.c:343)
>>  __qdisc_run (net/sched/sch_generic.c:416)
>>  net_tx_action (net/core/dev.c:5286)
>>  handle_softirqs (kernel/softirq.c:555)
>>  __irq_exit_rcu (kernel/softirq.c:589)
>>  sysvec_apic_timer_interrupt (arch/x86/kernel/apic/apic.c:1043)
>>
>> The warning triggers as this:
>> packet_sendmsg
>>    packet_snd //skb->sk is packet sk
>>       __dev_queue_xmit
>>          __dev_xmit_skb //q->enqueue is not NULL
>>              __qdisc_run
>>                sch_direct_xmit
>>                  dev_hard_start_xmit
>>                    ipvlan_start_xmit
>>                       ipvlan_xmit_mode_l3 //l3 mode
>>                         ipvlan_process_outbound //vepa flag
>>                           ipvlan_process_v6_outbound
>>                             ip6_local_out
>>                                 __ip6_finish_output
>>                                   ip6_finish_output2 //multicast packet
>>                                     sk_mc_loop //sk->sk_family is AF_PACKET
>>
>> Call ip{6}_local_out() with NULL sk in ipvlan as other tunnels to fix this.
>>
>> Fixes: f60e5990d9c1 ("ipv6: protect skb->sk accesses from recursive dereference inside the stack")
> 
> The patch LGTM, but the above fixes tag looks incorrect, I think the
> reproducer should splat even before such commit as the relevant warning
> will be still there and should be still reachable.

Yes, it should be Fixes: 2ad7bf363841 ("ipvlan: Initial check-in of the IPVLAN driver."), will post v2.
> 
> Cheers,
> 
> Paolo
> 
> .
>
diff mbox series

Patch

diff --git a/drivers/net/ipvlan/ipvlan_core.c b/drivers/net/ipvlan/ipvlan_core.c
index 2d5b021b4ea6..fef4eff7753a 100644
--- a/drivers/net/ipvlan/ipvlan_core.c
+++ b/drivers/net/ipvlan/ipvlan_core.c
@@ -439,7 +439,7 @@  static noinline_for_stack int ipvlan_process_v4_outbound(struct sk_buff *skb)
 
 	memset(IPCB(skb), 0, sizeof(*IPCB(skb)));
 
-	err = ip_local_out(net, skb->sk, skb);
+	err = ip_local_out(net, NULL, skb);
 	if (unlikely(net_xmit_eval(err)))
 		DEV_STATS_INC(dev, tx_errors);
 	else
@@ -494,7 +494,7 @@  static int ipvlan_process_v6_outbound(struct sk_buff *skb)
 
 	memset(IP6CB(skb), 0, sizeof(*IP6CB(skb)));
 
-	err = ip6_local_out(dev_net(dev), skb->sk, skb);
+	err = ip6_local_out(dev_net(dev), NULL, skb);
 	if (unlikely(net_xmit_eval(err)))
 		DEV_STATS_INC(dev, tx_errors);
 	else