Commit 08dae678 authored by Christian Brauner's avatar Christian Brauner Committed by ZhangPeng
Browse files

erofs: reliably distinguish block based and fscache mode 

stable inclusion
from stable-v6.6.32
commit f9b877a7ee312ec8ce17598a7ef85cb820d7c371
bugzilla: https://gitee.com/openeuler/kernel/issues/IA4MGD

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=f9b877a7ee312ec8ce17598a7ef85cb820d7c371



--------------------------------

commit 7af2ae1b1531feab5d38ec9c8f472dc6cceb4606 upstream.

When erofs_kill_sb() is called in block dev based mode, s_bdev may not
have been initialised yet, and if CONFIG_EROFS_FS_ONDEMAND is enabled,
it will be mistaken for fscache mode, and then attempt to free an anon_dev
that has never been allocated, triggering the following warning:

============================================
ida_free called for id=0 which is not allocated.
WARNING: CPU: 14 PID: 926 at lib/idr.c:525 ida_free+0x134/0x140
Modules linked in:
CPU: 14 PID: 926 Comm: mount Not tainted 6.9.0-rc3-dirty #630
RIP: 0010:ida_free+0x134/0x140
Call Trace:
 <TASK>
 erofs_kill_sb+0x81/0x90
 deactivate_locked_super+0x35/0x80
 get_tree_bdev+0x136/0x1e0
 vfs_get_tree+0x2c/0xf0
 do_new_mount+0x190/0x2f0
 [...]
============================================

Now when erofs_kill_sb() is called, erofs_sb_info must have been
initialised, so use sbi->fsid to distinguish between the two modes.

Signed-off-by: default avatarChristian Brauner <brauner@kernel.org>
Signed-off-by: default avatarBaokun Li <libaokun1@huawei.com>
Reviewed-by: default avatarJingbo Xu <jefflexu@linux.alibaba.com>
Reviewed-by: default avatarGao Xiang <hsiangkao@linux.alibaba.com>
Reviewed-by: default avatarChao Yu <chao@kernel.org>
Link: https://lore.kernel.org/r/20240419123611.947084-3-libaokun1@huawei.com


Signed-off-by: default avatarGao Xiang <hsiangkao@linux.alibaba.com>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: default avatarZhangPeng <zhangpeng362@huawei.com>
parent c949e036

fs/erofs/super.c

+2 −6
Original line number Diff line number Diff line
@@ -786,17 +786,13 @@ static int erofs_init_fs_context(struct fs_context *fc) 


static void erofs_kill_sb(struct super_block *sb)

{

	struct erofs_sb_info *sbi;

	struct erofs_sb_info *sbi = EROFS_SB(sb);



	if (erofs_is_fscache_mode(sb))

	if (IS_ENABLED(CONFIG_EROFS_FS_ONDEMAND) && sbi->fsid)

		kill_anon_super(sb);

	else

		kill_block_super(sb);



	sbi = EROFS_SB(sb);

	if (!sbi)

		return;



	erofs_free_dev_context(sbi->devs);

	fs_put_dax(sbi->dax_dev, NULL);

	erofs_fscache_unregister_fs(sb);