3.2-stable review patch. If anyone has any objections, please let me know.
------------------ From: Jiang Liu <[email protected]> commit 55ca6140e9bb307efc97a9301a4f501de02a6fd6 upstream. 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. [[email protected]: use raw_spin_lock/unlock] Signed-off-by: Jiang Liu <[email protected]> Acked-by: Jim Keniston <[email protected]> Acked-by: Ananth N Mavinakayanahalli <[email protected]> Cc: Masami Hiramatsu <[email protected]> Cc: Anil S Keshavamurthy <[email protected]> Cc: "David S. Miller" <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> --- kernel/kprobes.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) --- a/kernel/kprobes.c +++ b/kernel/kprobes.c @@ -1673,8 +1673,12 @@ static int __kprobes pre_handler_kretpro 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); -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
