[PATCH 6.8 579/715] f2fs: compress: fix to check compress flag w/ .i_sem lock

From: Sasha Levin
Date: Sun Mar 24 2024 - 20:45:04 EST


From: Chao Yu <chao@xxxxxxxxxx>

[ Upstream commit ea59b12ac69774c08aa95cd5b6100700ea0cce97 ]

It needs to check compress flag w/ .i_sem lock, otherwise, compressed
inode may be disabled after the check condition, it's not needed to
set compress option on non-compress inode.

Fixes: e1e8debec656 ("f2fs: add F2FS_IOC_SET_COMPRESS_OPTION ioctl")
Signed-off-by: Chao Yu <chao@xxxxxxxxxx>
Signed-off-by: Jaegeuk Kim <jaegeuk@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
fs/f2fs/file.c | 12 ++++++++----
1 file changed, 8 insertions(+), 4 deletions(-)

diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c
index 1ff1c45e19271..caab20648b951 100644
--- a/fs/f2fs/file.c
+++ b/fs/f2fs/file.c
@@ -3994,16 +3994,20 @@ static int f2fs_ioc_set_compress_option(struct file *filp, unsigned long arg)
sizeof(option)))
return -EFAULT;

- if (!f2fs_compressed_file(inode) ||
- option.log_cluster_size < MIN_COMPRESS_LOG_SIZE ||
- option.log_cluster_size > MAX_COMPRESS_LOG_SIZE ||
- option.algorithm >= COMPRESS_MAX)
+ if (option.log_cluster_size < MIN_COMPRESS_LOG_SIZE ||
+ option.log_cluster_size > MAX_COMPRESS_LOG_SIZE ||
+ option.algorithm >= COMPRESS_MAX)
return -EINVAL;

file_start_write(filp);
inode_lock(inode);

f2fs_down_write(&F2FS_I(inode)->i_sem);
+ if (!f2fs_compressed_file(inode)) {
+ ret = -EINVAL;
+ goto out;
+ }
+
if (f2fs_is_mmap_file(inode) || get_dirty_pages(inode)) {
ret = -EBUSY;
goto out;
--
2.43.0