| Message ID | 1404119568-4097-2-git-send-email-Anand.Jain@oracle.com (mailing list archive) |
|---|---|
| State | Accepted |
| Headers | show |
diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c index 74ef9bf..cac015f 100644 --- a/fs/btrfs/super.c +++ b/fs/btrfs/super.c @@ -1940,6 +1940,8 @@ static int btrfs_show_devname(struct seq_file *m, struct dentry *root) list_for_each_entry(dev, head, dev_list) { if (dev->missing) continue; + if (!dev->name) + continue; if (!first_dev || dev->devid < first_dev->devid) first_dev = dev; }
dev->name is null but missing flag is not set. Strictly speaking the missing flag should have been set, but there are more places where code just checks if name is null. For now this patch does the same. stack: BUG: unable to handle kernel NULL pointer dereference at 0000000000000064 IP: [<ffffffffa0228908>] btrfs_show_devname+0x58/0xf0 [btrfs] [<ffffffff81198879>] show_vfsmnt+0x39/0x130 [<ffffffff81178056>] m_show+0x16/0x20 [<ffffffff8117d706>] seq_read+0x296/0x390 [<ffffffff8115aa7d>] vfs_read+0x9d/0x160 [<ffffffff8115b549>] SyS_read+0x49/0x90 [<ffffffff817abe52>] system_call_fastpath+0x16/0x1b reproducer: mkfs.btrfs -draid1 -mraid1 /dev/sdg1 /dev/sdg2 btrfstune -S 1 /dev/sdg1 modprobe -r btrfs && modprobe btrfs mount -o degraded /dev/sdg1 /btrfs btrfs dev add /dev/sdg3 /btrfs Signed-off-by: Anand Jain <Anand.Jain@oracle.com> --- fs/btrfs/super.c | 2 ++ 1 file changed, 2 insertions(+)