[27/27] kprobes: initialize before using a hlist
From: Greg KH <gregkh@suse.de>
Date: 2012-01-23 23:46:36
Also in:
lkml
2.6.32-longterm review patch. If anyone has any objections, please let me know.
------------------
From: Ananth N Mavinakayanahalli <redacted>
commit d496aab567e7e52b3e974c9192a5de6e77dce32c upstream.
Commit ef53d9c5e ("kprobes: improve kretprobe scalability with hashed
locking") introduced a bug where we can potentially leak
kretprobe_instances since we initialize a hlist head after having used
it.
Initialize the hlist head before using it.
Reported by: Jim Keniston [off-list ref]
Acked-by: Jim Keniston <redacted>
Signed-off-by: Ananth N Mavinakayanahalli <redacted>
Acked-by: Masami Hiramatsu <redacted>
Cc: Srinivasa D S <redacted>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
---
kernel/kprobes.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
--- a/kernel/kprobes.c
+++ b/kernel/kprobes.c@@ -466,6 +466,7 @@ void __kprobes kprobe_flush_task(struct /* Early boot. kretprobe_table_locks not yet initialized. */ return; + INIT_HLIST_HEAD(&empty_rp); hash = hash_ptr(tk, KPROBE_HASH_BITS); head = &kretprobe_inst_table[hash]; kretprobe_table_lock(hash, &flags);
@@ -474,7 +475,6 @@ void __kprobes kprobe_flush_task(struct recycle_rp_inst(ri, &empty_rp); } kretprobe_table_unlock(hash, &flags); - INIT_HLIST_HEAD(&empty_rp); hlist_for_each_entry_safe(ri, node, tmp, &empty_rp, hlist) { hlist_del(&ri->hlist); kfree(ri);