[PATCH] wrong error path in dup_fd() leading to oopses in RCU
authorKirill Korotaev <dev@openvz.org>
Fri, 31 Mar 2006 13:58:46 +0000 (17:58 +0400)
committerLinus Torvalds <torvalds@g5.osdl.org>
Fri, 31 Mar 2006 20:25:46 +0000 (12:25 -0800)
commit428622986858aebddc32d022af65e88b9d2ea8bb
tree888b968f53e55d81386836ae3f43f46cea4ad6ce
parente358c1a2c45f7ec32d77cc09a2bb42d6823a4193
[PATCH] wrong error path in dup_fd() leading to oopses in RCU

Wrong error path in dup_fd() - it should return NULL on error,
not an address of already freed memory :/

Triggered by OpenVZ stress test suite.

What is interesting is that it was causing different oopses in RCU like
below:
Call Trace:
   [<c013492c>] rcu_do_batch+0x2c/0x80
   [<c0134bdd>] rcu_process_callbacks+0x3d/0x70
   [<c0126cf3>] tasklet_action+0x73/0xe0
   [<c01269aa>] __do_softirq+0x10a/0x130
   [<c01058ff>] do_softirq+0x4f/0x60
   =======================
   [<c0113817>] smp_apic_timer_interrupt+0x77/0x110
   [<c0103b54>] apic_timer_interrupt+0x1c/0x24
  Code:  Bad EIP value.
   <0>Kernel panic - not syncing: Fatal exception in interrupt

Signed-Off-By: Pavel Emelianov <xemul@sw.ru>
Signed-Off-By: Dmitry Mishin <dim@openvz.org>
Signed-Off-By: Kirill Korotaev <dev@openvz.org>
Signed-Off-By: Linus Torvalds <torvalds@osdl.org>
kernel/fork.c