github-mirror/linux
1
0
Fork 0
mirror of https://github.com/torvalds/linux.git synced 2026-06-08 06:25:52 +02:00
Code Issues Actions Packages Projects Releases Wiki Activity Graph

md: add mddev->pers to avoid potential NULL pointer dereference

Browse Source 
commit ee37e62191 upstream.

When doing re-add, we need to ensure rdev->mddev->pers is not NULL,
which can avoid potential NULL pointer derefence in fallowing
add_bound_rdev().

Fixes: a6da4ef85c ("md: re-add a failed disk")
Cc: Xiao Ni <xni@redhat.com>
Cc: NeilBrown <neilb@suse.com>
Cc: <stable@vger.kernel.org> # 4.4+
Reviewed-by: NeilBrown <neilb@suse.com>
Signed-off-by: Yufen Yu <yuyufen@huawei.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Yufen Yu 2019-04-02 14:22:14 +08:00 committed by Greg Kroah-Hartman
parent 3deaa1dc2f
commit 10cb519c3e
1 changed files with 4 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

6
drivers/md/md.c
View File

@ -2860,8 +2860,10 @@ state_store(struct md_rdev *rdev, const char *buf, size_t len)
err = 0;
}
} else if (cmd_match(buf, "re-add")) {
if (test_bit(Faulty, &rdev->flags) && (rdev->raid_disk == -1) &&
rdev->saved_raid_disk >= 0) {
if (!rdev->mddev->pers)
err = -EINVAL;
else if (test_bit(Faulty, &rdev->flags) && (rdev->raid_disk == -1) &&
rdev->saved_raid_disk >= 0) {
/* clear_bit is performed _after_ all the devices
* have their local Faulty bit cleared. If any writes
* happen in the meantime in the local node, they