This Linux kernel change "aio: fix possible invalid memory access when DEBUG is enabled" is included in the Linux 3.9 release. This change is authored by Zhao Hongjiang <zhaohongjiang [at] huawei.com> on Fri Apr 26 11:03:53 2013 +0800. The commit for this change in Linux stable tree is 91d80a8 (patch).
aio: fix possible invalid memory access when DEBUG is enabled dprintk() shouldn't access @ring after it's unmapped. Signed-off-by: Zhao Hongjiang <[email protected]> Cc: [email protected] Signed-off-by: Linus Torvalds <[email protected]>
There are 2 lines of Linux source code added/deleted in this change. Code changes to Linux kernel are as follows.
fs/aio.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/fs/aio.c b/fs/aio.c index 3f941f2..1dc8786 100644 --- a/fs/aio.c +++ b/fs/aio.c @@ -1029,9 +1029,9 @@ static int aio_read_evt(struct kioctx *ioctx, struct io_event *ent) spin_unlock(&info->ring_lock); out: - kunmap_atomic(ring); dprintk("leaving aio_read_evt: %d h%lu t%lun", ret, (unsigned long)ring->head, (unsigned long)ring->tail); + kunmap_atomic(ring); return ret; }