From: Zhao Heming <heming.zhao@suse.com>
To: linux-raid@vger.kernel.org
Cc: Zhao Heming <heming.zhao@suse.com>
Subject: [PATCH] md-cluster: fix wild pointer of unlock_all_bitmaps()
Date: Thu, 9 Jul 2020 11:29:29 +0800 [thread overview]
Message-ID: <1594265369-9468-1-git-send-email-heming.zhao@suse.com> (raw)
reproduction steps:
```
node1 # mdadm -C /dev/md0 -b clustered -e 1.2 -n 2 -l mirror /dev/sda
/dev/sdb
node2 # mdadm -A /dev/md0 /dev/sda /dev/sdb
node1 # mdadm -G /dev/md0 -b none
mdadm: failed to remove clustered bitmap.
node1 # mdadm -S --scan
^C <==== mdadm hung & kernel crash
```
kernel stack:
```
[ 335.230657] general protection fault: 0000 [#1] SMP NOPTI
[...]
[ 335.230848] Call Trace:
[ 335.230873] ? unlock_all_bitmaps+0x5/0x70 [md_cluster]
[ 335.230886] unlock_all_bitmaps+0x3d/0x70 [md_cluster]
[ 335.230899] leave+0x10f/0x190 [md_cluster]
[ 335.230932] ? md_super_wait+0x93/0xa0 [md_mod]
[ 335.230947] ? leave+0x5/0x190 [md_cluster]
[ 335.230973] md_cluster_stop+0x1a/0x30 [md_mod]
[ 335.230999] md_bitmap_free+0x142/0x150 [md_mod]
[ 335.231013] ? _cond_resched+0x15/0x40
[ 335.231025] ? mutex_lock+0xe/0x30
[ 335.231056] __md_stop+0x1c/0xa0 [md_mod]
[ 335.231083] do_md_stop+0x160/0x580 [md_mod]
[ 335.231119] ? 0xffffffffc05fb078
[ 335.231148] md_ioctl+0xa04/0x1930 [md_mod]
[ 335.231165] ? filename_lookup+0xf2/0x190
[ 335.231179] blkdev_ioctl+0x93c/0xa10
[ 335.231205] ? _cond_resched+0x15/0x40
[ 335.231214] ? __check_object_size+0xd4/0x1a0
[ 335.231224] block_ioctl+0x39/0x40
[ 335.231243] do_vfs_ioctl+0xa0/0x680
[ 335.231253] ksys_ioctl+0x70/0x80
[ 335.231261] __x64_sys_ioctl+0x16/0x20
[ 335.231271] do_syscall_64+0x65/0x1f0
[ 335.231278] entry_SYSCALL_64_after_hwframe+0x44/0xa9
```
Signed-off-by: Zhao Heming <heming.zhao@suse.com>
---
drivers/md/md-cluster.c | 1 +
1 file changed, 1 insertion(+)
diff --git a/drivers/md/md-cluster.c b/drivers/md/md-cluster.c
index 813a99ffa86f..73fd50e77975 100644
--- a/drivers/md/md-cluster.c
+++ b/drivers/md/md-cluster.c
@@ -1518,6 +1518,7 @@ static void unlock_all_bitmaps(struct mddev *mddev)
}
}
kfree(cinfo->other_bitmap_lockres);
+ cinfo->other_bitmap_lockres = NULL;
}
}
--
2.16.4
reply other threads:[~2020-07-09 3:29 UTC|newest]
Thread overview: [no followups] expand[flat|nested] mbox.gz Atom feed
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=1594265369-9468-1-git-send-email-heming.zhao@suse.com \
--to=heming.zhao@suse.com \
--cc=linux-raid@vger.kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).