| Message ID | 20220312214505.3294762-1-eric.dumazet@gmail.com (mailing list archive) |
|---|---|
| State | Accepted |
| Commit | fc93db153b0187a9047f00bfd5cce75108530593 |
| Delegated to: | Netdev Maintainers |
| Headers | show |
| Series | [net-next] net: disable preemption in dev_core_stats_XXX_inc() helpers | expand |
On Sat, 2022-03-12 at 13:45 -0800, Eric Dumazet wrote: > From: Eric Dumazet <edumazet@google.com> > > syzbot was kind enough to remind us that dev->{tx_dropped|rx_dropped} > could be increased in process context. > > BUG: using smp_processor_id() in preemptible [00000000] code: syz-executor413/3593 > caller is netdev_core_stats_alloc+0x98/0x110 net/core/dev.c:10298 > CPU: 1 PID: 3593 Comm: syz-executor413 Not tainted 5.17.0-rc7-syzkaller-02426-g97aeb877de7f #0 > Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 > Call Trace: > <TASK> > __dump_stack lib/dump_stack.c:88 [inline] > dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106 > check_preemption_disabled+0x16b/0x170 lib/smp_processor_id.c:49 > netdev_core_stats_alloc+0x98/0x110 net/core/dev.c:10298 > dev_core_stats include/linux/netdevice.h:3855 [inline] > dev_core_stats_rx_dropped_inc include/linux/netdevice.h:3866 [inline] > tun_get_user+0x3455/0x3ab0 drivers/net/tun.c:1800 > tun_chr_write_iter+0xe1/0x200 drivers/net/tun.c:2015 > call_write_iter include/linux/fs.h:2074 [inline] > new_sync_write+0x431/0x660 fs/read_write.c:503 > vfs_write+0x7cd/0xae0 fs/read_write.c:590 > ksys_write+0x12d/0x250 fs/read_write.c:643 > do_syscall_x64 arch/x86/entry/common.c:50 [inline] > do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 > entry_SYSCALL_64_after_hwframe+0x44/0xae > RIP: 0033:0x7f2cf4f887e3 > Code: 5d 41 5c 41 5d 41 5e e9 9b fd ff ff 66 2e 0f 1f 84 00 00 00 00 00 90 64 8b 04 25 18 00 00 00 85 c0 75 14 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 55 c3 0f 1f 40 00 48 83 ec 28 48 89 54 24 18 > RSP: 002b:00007ffd50dd5fd8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 > RAX: ffffffffffffffda RBX: 00007ffd50dd6000 RCX: 00007f2cf4f887e3 > RDX: 000000000000002a RSI: 0000000000000000 RDI: 00000000000000c8 > RBP: 0000000000000003 R08: 0000000000000000 R09: 0000000000000000 > R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 > R13: 00007ffd50dd5ff0 R14: 00007ffd50dd5fe8 R15: 00007ffd50dd5fe4 > </TASK> > > Fixes: 625788b58445 ("net: add per-cpu storage and net->core_stats") > Signed-off-by: Eric Dumazet <edumazet@google.com> > Cc: jeffreyji <jeffreyji@google.com> > Cc: Brian Vazquez <brianvv@google.com> > Cc: Jakub Kicinski <kuba@kernel.org> > Cc: Paolo Abeni <pabeni@redhat.com> > --- > include/linux/netdevice.h | 6 +++++- > 1 file changed, 5 insertions(+), 1 deletion(-) > > diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h > index 0d994710b3352395b8c6d6fd53affb2fe0cea39f..8cbe96ce0a2cd9e4f02168835d460d1c91901430 100644 > --- a/include/linux/netdevice.h > +++ b/include/linux/netdevice.h > @@ -3858,10 +3858,14 @@ static inline struct net_device_core_stats *dev_core_stats(struct net_device *de > #define DEV_CORE_STATS_INC(FIELD) \ > static inline void dev_core_stats_##FIELD##_inc(struct net_device *dev) \ > { \ > - struct net_device_core_stats *p = dev_core_stats(dev); \ > + struct net_device_core_stats *p; \ > + \ > + preempt_disable(); \ > + p = dev_core_stats(dev); \ > \ > if (p) \ > local_inc(&p->FIELD); \ > + preempt_enable(); \ > } > DEV_CORE_STATS_INC(rx_dropped) > DEV_CORE_STATS_INC(tx_dropped) LGTM, thanks Eric! Acked-by: Paolo Abeni <pabeni@redhat.com>
Hello: This patch was applied to netdev/net-next.git (master) by Jakub Kicinski <kuba@kernel.org>: On Sat, 12 Mar 2022 13:45:05 -0800 you wrote: > From: Eric Dumazet <edumazet@google.com> > > syzbot was kind enough to remind us that dev->{tx_dropped|rx_dropped} > could be increased in process context. > > BUG: using smp_processor_id() in preemptible [00000000] code: syz-executor413/3593 > caller is netdev_core_stats_alloc+0x98/0x110 net/core/dev.c:10298 > CPU: 1 PID: 3593 Comm: syz-executor413 Not tainted 5.17.0-rc7-syzkaller-02426-g97aeb877de7f #0 > Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 > Call Trace: > <TASK> > __dump_stack lib/dump_stack.c:88 [inline] > dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106 > check_preemption_disabled+0x16b/0x170 lib/smp_processor_id.c:49 > netdev_core_stats_alloc+0x98/0x110 net/core/dev.c:10298 > dev_core_stats include/linux/netdevice.h:3855 [inline] > dev_core_stats_rx_dropped_inc include/linux/netdevice.h:3866 [inline] > tun_get_user+0x3455/0x3ab0 drivers/net/tun.c:1800 > tun_chr_write_iter+0xe1/0x200 drivers/net/tun.c:2015 > call_write_iter include/linux/fs.h:2074 [inline] > new_sync_write+0x431/0x660 fs/read_write.c:503 > vfs_write+0x7cd/0xae0 fs/read_write.c:590 > ksys_write+0x12d/0x250 fs/read_write.c:643 > do_syscall_x64 arch/x86/entry/common.c:50 [inline] > do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 > entry_SYSCALL_64_after_hwframe+0x44/0xae > RIP: 0033:0x7f2cf4f887e3 > Code: 5d 41 5c 41 5d 41 5e e9 9b fd ff ff 66 2e 0f 1f 84 00 00 00 00 00 90 64 8b 04 25 18 00 00 00 85 c0 75 14 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 55 c3 0f 1f 40 00 48 83 ec 28 48 89 54 24 18 > RSP: 002b:00007ffd50dd5fd8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 > RAX: ffffffffffffffda RBX: 00007ffd50dd6000 RCX: 00007f2cf4f887e3 > RDX: 000000000000002a RSI: 0000000000000000 RDI: 00000000000000c8 > RBP: 0000000000000003 R08: 0000000000000000 R09: 0000000000000000 > R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 > R13: 00007ffd50dd5ff0 R14: 00007ffd50dd5fe8 R15: 00007ffd50dd5fe4 > </TASK> > > [...] Here is the summary with links: - [net-next] net: disable preemption in dev_core_stats_XXX_inc() helpers https://git.kernel.org/netdev/net-next/c/fc93db153b01 You are awesome, thank you!
diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h index 0d994710b3352395b8c6d6fd53affb2fe0cea39f..8cbe96ce0a2cd9e4f02168835d460d1c91901430 100644 --- a/include/linux/netdevice.h +++ b/include/linux/netdevice.h @@ -3858,10 +3858,14 @@ static inline struct net_device_core_stats *dev_core_stats(struct net_device *de #define DEV_CORE_STATS_INC(FIELD) \ static inline void dev_core_stats_##FIELD##_inc(struct net_device *dev) \ { \ - struct net_device_core_stats *p = dev_core_stats(dev); \ + struct net_device_core_stats *p; \ + \ + preempt_disable(); \ + p = dev_core_stats(dev); \ \ if (p) \ local_inc(&p->FIELD); \ + preempt_enable(); \ } DEV_CORE_STATS_INC(rx_dropped) DEV_CORE_STATS_INC(tx_dropped)