Ding Tianhong
2013-Sep-03 07:15 UTC
[Bridge] [PATCH net] bridge: netfiler: update find_inlist_lock_noload() more accurate
Baoquan He <baoquan.he at gmail.com> has report a problem which occurred by the following command: make SUBDIRS=net/bridge/netfilter/ cp /net/bridge/netfilter/ebtables.ko /lib/modules/3.11.0-rc7+/kernel/net/bridge/netfilter/ebtables.ko depmod modprobe ebtables.ko reboot ---------------------------------------------------------------------- [ 48.895000] BUG: soft lockup - CPU#1 stuck for 22s! [ebtables:444] [ 48.901191] Modules linked in: bnep(F) bluetooth(F) ebtables(F) ip6table_filter(F) ip6_tables(F) rfkill(F) snd_hda_intel(F+) snd_hda_codec(F) snd_hwdep(F) snd_seq(F) sn) [ 48.950034] CPU: 1 PID: 444 Comm: ebtables Tainted: GF D 3.11.0-rc7+ #1 [ 48.957433] Hardware name: Hewlett-Packard HP Z420 Workstation/1589, BIOS J61 v01.02 03/09/2012 [ 48.966131] task: ffff88040c2dc650 ti: ffff8804187d2000 task.ti: ffff8804187d2000 [ 48.973610] RIP: 0010:[<ffffffff812e57a7>] [<ffffffff812e57a7>] strcmp+0x27/0x40 [ 48.981119] RSP: 0018:ffff8804187d3db8 EFLAGS: 00000246 [ 48.986430] RAX: 0000000000000000 RBX: 00007fffda942730 RCX: ffff8804187d3fd8 [ 48.993566] RDX: 0000000000000000 RSI: ffff8804187d3e01 RDI: ffffffff81cb8a39 [ 49.000707] RBP: ffff8804187d3db8 R08: 00000000fffffff2 R09: 0000000000000000 [ 49.007841] R10: 0000000000000163 R11: 0000000000000000 R12: ffffffff8128300c [ 49.014972] R13: ffff8804187d3d98 R14: ffff8804187d3ef4 R15: 0000000000000004 [ 49.022112] FS: 00007faab6589740(0000) GS:ffff88042fc80000(0000) knlGS:0000000000000000 [ 49.030194] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 49.035942] CR2: 0000003f0d810414 CR3: 000000040d2cc000 CR4: 00000000000407e0 [ 49.043077] Stack: [ 49.045096] ffff8804187d3de8 ffffffffa0249674 0000000000000080 ffffffff81cb8180 [ 49.052559] 00007fffda942730 ffff8804187d3ef4 ffff8804187d3ea0 ffffffffa02497a9 [ 49.060020] 0000000000000000 00007265746c6966 0000003f0d7b92c0 00007fffda942850 [ 49.067487] Call Trace: [ 49.069949] [<ffffffffa0249674>] find_inlist_lock.constprop.16+0x54/0x100 [ebtables] [ 49.077779] [<ffffffffa02497a9>] do_ebt_get_ctl+0x89/0x1d0 [ebtables] [ 49.084306] [<ffffffff81551ca8>] nf_getsockopt+0x68/0x90 [ 49.089717] [<ffffffff81560d40>] ip_getsockopt+0x80/0xa0 [ 49.095113] [<ffffffff815835c5>] raw_getsockopt+0x25/0x50 [ 49.100588] [<ffffffff8150ddd4>] sock_common_getsockopt+0x14/0x20 [ 49.106766] [<ffffffff8150d208>] SyS_getsockopt+0x68/0xd0 [ 49.112257] [<ffffffff8162c682>] system_call_fastpath+0x16/0x1b [ 49.118260] Code: 00 00 00 00 55 48 89 e5 eb 0e 66 2e 0f 1f 84 00 00 00 00 00 84 c0 74 1c 48 83 c7 01 0f b6 47 ff 48 83 c6 01 3a 46 ff 74 eb 19 c0 <83> c8 01 5d c3 0f 1 [ 76.925880] BUG: soft lockup - CPU#1 stuck for 22s! [ebtables:444] [ 76.932069] Modules linked in: bnep(F) bluetooth(F) ebtables(F) ip6table_filter(F) ip6_tables(F) rfkill(F) snd_hda_intel(F+) snd_hda_codec(F) snd_hwdep(F) snd_seq(F) sn) [ 76.980847] CPU: 1 PID: 444 Comm: ebtables Tainted: GF D 3.11.0-rc7+ #1 [ 76.988245] Hardware name: Hewlett-Packard HP Z420 Workstation/1589, BIOS J61 v01.02 03/09/2012 [ 76.996940] task: ffff88040c2dc650 ti: ffff8804187d2000 task.ti: ffff8804187d2000 [ 77.004426] RIP: 0010:[<ffffffff812e5784>] [<ffffffff812e5784>] strcmp+0x4/0x40 [ 77.011849] RSP: 0018:ffff8804187d3db8 EFLAGS: 00000212 [ 77.017163] RAX: 0000000000000001 RBX: 00007fffda942730 RCX: ffff8804187d3fd8 [ 77.024304] RDX: 0000000000000000 RSI: ffff8804187d3e00 RDI: ffffffff81cb8a38 [ 77.031434] RBP: ffff8804187d3db8 R08: 00000000fffffff2 R09: 0000000000000000 [ 77.038566] R10: 0000000000000163 R11: 0000000000000000 R12: ffffffff8128300c [ 77.045699] R13: ffff8804187d3d98 R14: ffff8804187d3ef4 R15: 0000000000000004 [ 77.052842] FS: 00007faab6589740(0000) GS:ffff88042fc80000(0000) knlGS:0000000000000000 [ 77.060934] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 77.066668] CR2: 0000003f0d810414 CR3: 000000040d2cc000 CR4: 00000000000407e0 [ 77.073799] Stack: [ 77.075818] ffff8804187d3de8 ffffffffa0249674 0000000000000080 ffffffff81cb8180 [ 77.083287] 00007fffda942730 ffff8804187d3ef4 ffff8804187d3ea0 ffffffffa02497a9 [ 77.090749] 0000000000000000 00007265746c6966 0000003f0d7b92c0 00007fffda942850 [ 77.098215] Call Trace: [ 77.100668] [<ffffffffa0249674>] find_inlist_lock.constprop.16+0x54/0x100 [ebtables] [ 77.108500] [<ffffffffa02497a9>] do_ebt_get_ctl+0x89/0x1d0 [ebtables] [ 77.115035] [<ffffffff81551ca8>] nf_getsockopt+0x68/0x90 [ 77.120438] [<ffffffff81560d40>] ip_getsockopt+0x80/0xa0 [ 77.125845] [<ffffffff815835c5>] raw_getsockopt+0x25/0x50 [ 77.131328] [<ffffffff8150ddd4>] sock_common_getsockopt+0x14/0x20 [ 77.137515] [<ffffffff8150d208>] SyS_getsockopt+0x68/0xd0 [ 77.143011] [<ffffffff8162c682>] system_call_fastpath+0x16/0x1b [ 77.149019] Code: 0f 1f 80 00 00 00 00 48 83 c6 01 0f b6 4e ff 48 83 c2 01 84 c9 88 4a ff 75 ed 5d c3 66 66 2e 0f 1f 84 00 00 00 00 00 55 48 89 e5 <eb> 0e 66 2e 0f 1f 8 --------------------------------------------------------------------------- The find_inlist_lock did not distinguish the error whether lock failed or module non-existent, the imperfection processing procedure may course the problem. Return the correct value if mutex_lock_interruptible() failed, avoid confusion with that the modules is not exist, and deal with the return value in right way. After the patch, the problem didn't happened again, so I confident the bug was fixed. Reported-by: Baoquan He <baoquan.he at gmail.com> Signed-off-by: Ding Tianhong <dingtianhong at huawei.com> Cc: Baoquan He <baoquan.he at gmail.com> --- net/bridge/netfilter/ebtables.c | 17 +++++++---------- 1 file changed, 7 insertions(+), 10 deletions(-) diff --git a/net/bridge/netfilter/ebtables.c b/net/bridge/netfilter/ebtables.c index ac78024..e7fe9f8 100644 --- a/net/bridge/netfilter/ebtables.c +++ b/net/bridge/netfilter/ebtables.c @@ -322,17 +322,14 @@ static inline void * find_inlist_lock_noload(struct list_head *head, const char *name, int *error, struct mutex *mutex) { - struct { - struct list_head list; - char name[EBT_FUNCTION_MAXNAMELEN]; - } *e; + struct ebt_table *e; *error = mutex_lock_interruptible(mutex); if (*error != 0) - return NULL; + return ERR_PTR(-EINTR); list_for_each_entry(e, head, list) { - if (strcmp(e->name, name) == 0) + if (strcmp(e->name, name) == 0 && try_module_get(e->me)) return e; } *error = -ENOENT; @@ -1005,7 +1002,7 @@ static int do_replace_finish(struct net *net, struct ebt_replace *repl, goto free_counterstmp; t = find_table_lock(net, repl->name, &ret, &ebt_mutex); - if (!t) { + if (IS_ERR_OR_NULL(t)) { ret = -ENOENT; goto free_iterate; } @@ -1284,7 +1281,7 @@ static int do_update_counters(struct net *net, const char *name, return -ENOMEM; t = find_table_lock(net, name, &ret, &ebt_mutex); - if (!t) + if (IS_ERR_OR_NULL(t)) goto free_tmp; if (num_counters != t->private->nentries) { @@ -1504,7 +1501,7 @@ static int do_ebt_get_ctl(struct sock *sk, int cmd, void __user *user, int *len) return -EFAULT; t = find_table_lock(net, tmp.name, &ret, &ebt_mutex); - if (!t) + if (IS_ERR_OR_NULL(t)) return ret; switch(cmd) { @@ -2319,7 +2316,7 @@ static int compat_do_ebt_get_ctl(struct sock *sk, int cmd, return -EFAULT; t = find_table_lock(net, tmp.name, &ret, &ebt_mutex); - if (!t) + if (IS_ERR_OR_NULL(t)) return ret; xt_compat_lock(NFPROTO_BRIDGE); -- 1.8.2.1