From: Anand Jain anand.jain@oracle.com
mainline inclusion from mainline-v5.16-rc1 commit b7cb29e666fe79dda5dbe5f57fb7c92413bf161c category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/IA77UW CVE: CVE-2021-47599
Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?i...
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When we add a device to the seed filesystem (sprouting) it is a new filesystem (and fsid) on the device added. Update the latest_dev so that /proc/self/mounts shows the correct device.
Example:
$ btrfstune -S1 /dev/vg/seed $ mount /dev/vg/seed /btrfs mount: /btrfs: WARNING: device write-protected, mounted read-only.
$ cat /proc/self/mounts | grep btrfs /dev/mapper/vg-seed /btrfs btrfs ro,relatime,space_cache,subvolid=5,subvol=/ 0 0
$ btrfs dev add -f /dev/vg/new /btrfs
Before:
$ cat /proc/self/mounts | grep btrfs /dev/mapper/vg-seed /btrfs btrfs ro,relatime,space_cache,subvolid=5,subvol=/ 0 0
After:
$ cat /proc/self/mounts | grep btrfs /dev/mapper/vg-new /btrfs btrfs ro,relatime,space_cache,subvolid=5,subvol=/ 0 0
Tested-by: Su Yue l@damenly.su Signed-off-by: Anand Jain anand.jain@oracle.com Reviewed-by: David Sterba dsterba@suse.com Signed-off-by: David Sterba dsterba@suse.com Signed-off-by: Yifan Qiao qiaoyifan4@huawei.com --- fs/btrfs/volumes.c | 2 ++ 1 file changed, 2 insertions(+)
diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c index d38d5d7aecd4..2e7a8c1f6db4 100644 --- a/fs/btrfs/volumes.c +++ b/fs/btrfs/volumes.c @@ -2629,6 +2629,8 @@ int btrfs_init_new_device(struct btrfs_fs_info *fs_info, const char *device_path btrfs_abort_transaction(trans, ret); goto error_trans; } + btrfs_assign_next_active_device(fs_info->fs_devices->latest_dev, + device); }
device->fs_devices = fs_devices;