Re: [PATCH] lightnvm: pblk: fix use-after-free bug

From: Gustavo A. R. Silva
Date: Sat Dec 22 2018 - 15:05:41 EST

On 12/22/18 12:30 PM, Matias BjÃrling wrote:
On 12/22/18 8:39 AM, Gustavo A. R. Silva wrote:
Remove one of the calls to function bio_put(), so *bio* is only
freed once.

Notice that bio is being dereferenced in bio_put(), hence leading to
a use-after-free bug once *bio* has already been freed.

Addresses-Coverity-ID: 1475952 ("Use after free")
Fixes: 55d8ec35398e ("lightnvm: pblk: support packed metadata")
Signed-off-by: Gustavo A. R. Silva <gustavo@xxxxxxxxxxxxxx>
 drivers/lightnvm/pblk-recovery.c | 1 -
 1 file changed, 1 deletion(-)

diff --git a/drivers/lightnvm/pblk-recovery.c b/drivers/lightnvm/pblk-recovery.c
index 3fcf062d752c..5ee20da7bdb3 100644
--- a/drivers/lightnvm/pblk-recovery.c
+++ b/drivers/lightnvm/pblk-recovery.c
@@ -418,7 +418,6 @@ static int pblk_recov_scan_oob(struct pblk *pblk, struct pblk_line *line,
ÂÂÂÂÂ if (ret) {
ÂÂÂÂÂÂÂÂÂ pblk_err(pblk, "I/O submission failed: %d\n", ret);
ÂÂÂÂÂÂÂÂÂ bio_put(bio);
-ÂÂÂÂÂÂÂ bio_put(bio);
ÂÂÂÂÂÂÂÂÂ return ret;

Thanks Gustavo. I missed that one.

Jens, if possible could you please pick this up?

Happy holidays!

Glad to help. :)

Happy holidays everybody.