diff options
author | Keshavamurthy Anil S <anil.s.keshavamurthy@intel.com> | 2005-12-12 09:37:12 +0100 |
---|---|---|
committer | Linus Torvalds <torvalds@g5.osdl.org> | 2005-12-12 17:57:43 +0100 |
commit | adad0f331f9c693129e81e233c5461e2e7c3e443 (patch) | |
tree | 846b37c12e8a07b7f4f3f5dbecb4b060c2be01c1 | |
parent | [PATCH] add hlist_replace_rcu() (diff) | |
download | linux-adad0f331f9c693129e81e233c5461e2e7c3e443.tar.xz linux-adad0f331f9c693129e81e233c5461e2e7c3e443.zip |
[PATCH] kprobes: fix race in aggregate kprobe registration
When registering multiple kprobes at the same address, we leave a small
window where the kprobe hlist will not contain a reference to the
registered kprobe, leading to potentially, a system crash if the breakpoint
is hit on another processor.
Patch below now automically relpace the old kprobe with the new
kprobe from the hash list.
Signed-off-by: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: "Paul E. McKenney" <paulmck@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
-rw-r--r-- | kernel/kprobes.c | 5 |
1 files changed, 1 insertions, 4 deletions
diff --git a/kernel/kprobes.c b/kernel/kprobes.c index fde5a16a2913..e4f0fc62bd3e 100644 --- a/kernel/kprobes.c +++ b/kernel/kprobes.c @@ -399,10 +399,7 @@ static inline void add_aggr_kprobe(struct kprobe *ap, struct kprobe *p) INIT_LIST_HEAD(&ap->list); list_add_rcu(&p->list, &ap->list); - INIT_HLIST_NODE(&ap->hlist); - hlist_del_rcu(&p->hlist); - hlist_add_head_rcu(&ap->hlist, - &kprobe_table[hash_ptr(ap->addr, KPROBE_HASH_BITS)]); + hlist_replace_rcu(&p->hlist, &ap->hlist); } /* |