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| author | Jiang Liu <liuj97@gmail.com> | 2012-02-03 15:37:16 -0800 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2012-02-03 16:16:41 -0800 |
| commit | 55ca6140e9bb307efc97a9301a4f501de02a6fd6 (patch) | |
| tree | f0cc42df52d35a0c7d3bd2a074219eaf4a84e6a7 /kernel/kprobes.c | |
| parent | cbcb8346054073d000ecac324763372d6abd44ac (diff) | |
| download | lwn-55ca6140e9bb307efc97a9301a4f501de02a6fd6.tar.gz lwn-55ca6140e9bb307efc97a9301a4f501de02a6fd6.zip | |
kprobes: fix a memory leak in function pre_handler_kretprobe()
In function pre_handler_kretprobe(), the allocated kretprobe_instance
object will get leaked if the entry_handler callback returns non-zero.
This may cause all the preallocated kretprobe_instance objects exhausted.
This issue can be reproduced by changing
samples/kprobes/kretprobe_example.c to probe "mutex_unlock". And the fix
is straightforward: just put the allocated kretprobe_instance object back
onto the free_instances list.
[akpm@linux-foundation.org: use raw_spin_lock/unlock]
Signed-off-by: Jiang Liu <jiang.liu@huawei.com>
Acked-by: Jim Keniston <jkenisto@us.ibm.com>
Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'kernel/kprobes.c')
| -rw-r--r-- | kernel/kprobes.c | 6 |
1 files changed, 5 insertions, 1 deletions
diff --git a/kernel/kprobes.c b/kernel/kprobes.c index 29f5b65bee29..9788c0ec6f43 100644 --- a/kernel/kprobes.c +++ b/kernel/kprobes.c @@ -1673,8 +1673,12 @@ static int __kprobes pre_handler_kretprobe(struct kprobe *p, ri->rp = rp; ri->task = current; - if (rp->entry_handler && rp->entry_handler(ri, regs)) + if (rp->entry_handler && rp->entry_handler(ri, regs)) { + raw_spin_lock_irqsave(&rp->lock, flags); + hlist_add_head(&ri->hlist, &rp->free_instances); + raw_spin_unlock_irqrestore(&rp->lock, flags); return 0; + } arch_prepare_kretprobe(ri, regs); |