Commit 2d9073922bc73f8cb847ce354f0896205f6981a1
Committed by
David S. Miller
David S. Miller
1 parent
f3a0592b37
Exists in
master
and in
7 other branches
[ATM]: Clip timer race.
By inspection, the clip idle timer code is racy on SMP. Here is a safe version of timer management. Untested, I don't have ATM hardware. Signed-off-by: Stephen Hemminger <shemminger@osdl.org> Signed-off-by: David S. Miller <davem@davemloft.net>
Showing 1 changed file with 5 additions and 11 deletions Side-by-side Diff
net/atm/clip.c
| ... | ... | @@ -54,9 +54,7 @@ |
| 54 | 54 | static struct atm_vcc *atmarpd; |
| 55 | 55 | static struct neigh_table clip_tbl; |
| 56 | 56 | static struct timer_list idle_timer; |
| 57 | -static int start_timer = 1; | |
| 58 | 57 | |
| 59 | - | |
| 60 | 58 | static int to_atmarpd(enum atmarp_ctrl_type type,int itf,unsigned long ip) |
| 61 | 59 | { |
| 62 | 60 | struct sock *sk; |
| ... | ... | @@ -725,13 +723,8 @@ |
| 725 | 723 | return -EADDRINUSE; |
| 726 | 724 | } |
| 727 | 725 | |
| 728 | - if (start_timer) { | |
| 729 | - start_timer = 0; | |
| 730 | - init_timer(&idle_timer); | |
| 731 | - idle_timer.expires = jiffies+CLIP_CHECK_INTERVAL*HZ; | |
| 732 | - idle_timer.function = idle_timer_check; | |
| 733 | - add_timer(&idle_timer); | |
| 734 | - } | |
| 726 | + mod_timer(&idle_timer, jiffies+CLIP_CHECK_INTERVAL*HZ); | |
| 727 | + | |
| 735 | 728 | atmarpd = vcc; |
| 736 | 729 | set_bit(ATM_VF_META,&vcc->flags); |
| 737 | 730 | set_bit(ATM_VF_READY,&vcc->flags); |
| ... | ... | @@ -1002,6 +995,8 @@ |
| 1002 | 995 | register_netdevice_notifier(&clip_dev_notifier); |
| 1003 | 996 | register_inetaddr_notifier(&clip_inet_notifier); |
| 1004 | 997 | |
| 998 | + setup_timer(&idle_timer, idle_timer_check, 0); | |
| 999 | + | |
| 1005 | 1000 | #ifdef CONFIG_PROC_FS |
| 1006 | 1001 | { |
| 1007 | 1002 | struct proc_dir_entry *p; |
| ... | ... | @@ -1029,8 +1024,7 @@ |
| 1029 | 1024 | /* First, stop the idle timer, so it stops banging |
| 1030 | 1025 | * on the table. |
| 1031 | 1026 | */ |
| 1032 | - if (start_timer == 0) | |
| 1033 | - del_timer(&idle_timer); | |
| 1027 | + del_timer_sync(&idle_timer); | |
| 1034 | 1028 | |
| 1035 | 1029 | /* Next, purge the table, so that the device |
| 1036 | 1030 | * unregister loop below does not hang due to |