2005-04-11 14:56:30

by S. P. Prasanna

[permalink] [raw]
Subject: [PATCH] Kprobes: Oops! in unregister_kprobe()

Hi,

Please find the patch below to fix Oops! in unregister_kprobe().
Please let me know if you any issues.

Thanks
Prasanna


kernel oops! when unregister_kprobe() is called on a non-registered
kprobe. This patch fixes the above problem by checking if the probe exists
before unregistering.

Signed-off-by: Prasanna S Panchamukhi <[email protected]>


---

linux-2.6.12-rc2-prasanna/kernel/kprobes.c | 6 +++++-
1 files changed, 5 insertions(+), 1 deletion(-)

diff -puN kernel/kprobes.c~kprobes-unregister-oops-fix kernel/kprobes.c
--- linux-2.6.12-rc2/kernel/kprobes.c~kprobes-unregister-oops-fix 2005-04-11 17:23:34.000000000 +0530
+++ linux-2.6.12-rc2-prasanna/kernel/kprobes.c 2005-04-11 17:32:50.000000000 +0530
@@ -110,13 +110,17 @@ rm_kprobe:
void unregister_kprobe(struct kprobe *p)
{
unsigned long flags;
- arch_remove_kprobe(p);
spin_lock_irqsave(&kprobe_lock, flags);
+ if (!get_kprobe(p->addr)) {
+ spin_unlock_irqrestore(&kprobe_lock, flags);
+ return;
+ }
*p->addr = p->opcode;
hlist_del(&p->hlist);
flush_icache_range((unsigned long) p->addr,
(unsigned long) p->addr + sizeof(kprobe_opcode_t));
spin_unlock_irqrestore(&kprobe_lock, flags);
+ arch_remove_kprobe(p);
}



_
--

Prasanna S Panchamukhi
Linux Technology Center
India Software Labs, IBM Bangalore
Ph: 91-80-25044636
<[email protected]>