From f4e3634a3b642225a530c292fdb1e8a4007507f5 Mon Sep 17 00:00:00 2001 From: Zhihao Cheng Date: Mon, 31 May 2021 20:52:09 +0800 Subject: ubifs: Fix races between xattr_{set|get} and listxattr operations UBIFS may occur some problems with concurrent xattr_{set|get} and listxattr operations, such as assertion failure, memory corruption, stale xattr value[1]. Fix it by importing a new rw-lock in @ubifs_inode to serilize write operations on xattr, concurrent read operations are still effective, just like ext4. [1] https://lore.kernel.org/linux-mtd/20200630130438.141649-1-houtao1@huawei.com Fixes: 1e51764a3c2ac05a23 ("UBIFS: add new flash file system") Cc: stable@vger.kernel.org # v2.6+ Signed-off-by: Zhihao Cheng Reviewed-by: Sascha Hauer Signed-off-by: Richard Weinberger --- fs/ubifs/ubifs.h | 2 ++ 1 file changed, 2 insertions(+) (limited to 'fs/ubifs/ubifs.h') diff --git a/fs/ubifs/ubifs.h b/fs/ubifs/ubifs.h index b65c599a386a..7e978f421430 100644 --- a/fs/ubifs/ubifs.h +++ b/fs/ubifs/ubifs.h @@ -356,6 +356,7 @@ struct ubifs_gced_idx_leb { * @ui_mutex: serializes inode write-back with the rest of VFS operations, * serializes "clean <-> dirty" state changes, serializes bulk-read, * protects @dirty, @bulk_read, @ui_size, and @xattr_size + * @xattr_sem: serilizes write operations (remove|set|create) on xattr * @ui_lock: protects @synced_i_size * @synced_i_size: synchronized size of inode, i.e. the value of inode size * currently stored on the flash; used only for regular file @@ -409,6 +410,7 @@ struct ubifs_inode { unsigned int bulk_read:1; unsigned int compr_type:2; struct mutex ui_mutex; + struct rw_semaphore xattr_sem; spinlock_t ui_lock; loff_t synced_i_size; loff_t ui_size; -- cgit v1.2.3