This is a note to let you know that I've just added the patch titled f2fs: fix race condition on setting FI_NO_EXTENT flag to the 5.10-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: f2fs-fix-race-condition-on-setting-fi_no_extent-flag.patch and it can be found in the queue-5.10 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit 7f6799823f17990f088b74c7c5c4c89f5c5ce373 Author: Zhang Qilong <zhangqilong3@xxxxxxxxxx> Date: Mon Sep 5 12:59:17 2022 +0800 f2fs: fix race condition on setting FI_NO_EXTENT flag [ Upstream commit 07725adc55c0a414c10acb5c8c86cea34b95ddef ] The following scenarios exist. process A: process B: ->f2fs_drop_extent_tree ->f2fs_update_extent_cache_range ->f2fs_update_extent_tree_range ->write_lock ->set_inode_flag ->is_inode_flag_set ->__free_extent_tree // Shouldn't // have been // cleaned up // here ->write_lock In this case, the "FI_NO_EXTENT" flag is set between f2fs_update_extent_tree_range and is_inode_flag_set by other process. it leads to clearing the whole exten tree which should not have happened. And we fix it by move the setting it to the range of write_lock. Fixes:5f281fab9b9a3 ("f2fs: disable extent_cache for fcollapse/finsert inodes") Signed-off-by: Zhang Qilong <zhangqilong3@xxxxxxxxxx> Reviewed-by: Chao Yu <chao@xxxxxxxxxx> Signed-off-by: Jaegeuk Kim <jaegeuk@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/fs/f2fs/extent_cache.c b/fs/f2fs/extent_cache.c index 3ebf976a682d..bd16c78b5bf2 100644 --- a/fs/f2fs/extent_cache.c +++ b/fs/f2fs/extent_cache.c @@ -762,9 +762,8 @@ void f2fs_drop_extent_tree(struct inode *inode) if (!f2fs_may_extent_tree(inode)) return; - set_inode_flag(inode, FI_NO_EXTENT); - write_lock(&et->lock); + set_inode_flag(inode, FI_NO_EXTENT); __free_extent_tree(sbi, et); if (et->largest.len) { et->largest.len = 0;