Patch "f2fs: compress: fix to check zstd compress level correctly in mount option" has been added to the 6.6-stable tree

[Sasha Levin <sashal@xxxxxxxxxx>]

This is a note to let you know that I've just added the patch titled

    f2fs: compress: fix to check zstd compress level correctly in mount option

to the 6.6-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-compress-fix-to-check-zstd-compress-level-corre.patch
and it can be found in the queue-6.6 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.



commit b1dc65a996476d54c65e43b9faa3cf893513eb9e
Author: Chao Yu <chao@xxxxxxxxxx>
Date:   Tue Feb 13 00:08:18 2024 +0800

    f2fs: compress: fix to check zstd compress level correctly in mount option
    
    [ Upstream commit e39602da752cd1d0462e3fa04074146f6f2803f6 ]
    
    f2fs only support to config zstd compress level w/ a positive number due
    to layout design, but since commit e0c1b49f5b67 ("lib: zstd: Upgrade to
    latest upstream zstd version 1.4.10"), zstd supports negative compress
    level, so that zstd_min_clevel() may return a negative number, then w/
    below mount option, .compress_level can be configed w/ a negative number,
    which is not allowed to f2fs, let's add check condition to avoid it.
    
    mount -o compress_algorithm=zstd:4294967295 /dev/sdx /mnt/f2fs
    
    Fixes: 00e120b5e4b5 ("f2fs: assign default compression level")
    Signed-off-by: Chao Yu <chao@xxxxxxxxxx>
    Signed-off-by: Jaegeuk Kim <jaegeuk@xxxxxxxxxx>
    Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>

diff --git a/fs/f2fs/super.c b/fs/f2fs/super.c
index d0a659b906656..76d94889e45cd 100644
--- a/fs/f2fs/super.c
+++ b/fs/f2fs/super.c
@@ -648,7 +648,7 @@ static int f2fs_set_lz4hc_level(struct f2fs_sb_info *sbi, const char *str)
 #ifdef CONFIG_F2FS_FS_ZSTD
 static int f2fs_set_zstd_level(struct f2fs_sb_info *sbi, const char *str)
 {
-	unsigned int level;
+	int level;
 	int len = 4;
 
 	if (strlen(str) == len) {
@@ -662,9 +662,15 @@ static int f2fs_set_zstd_level(struct f2fs_sb_info *sbi, const char *str)
 		f2fs_info(sbi, "wrong format, e.g. <alg_name>:<compr_level>");
 		return -EINVAL;
 	}
-	if (kstrtouint(str + 1, 10, &level))
+	if (kstrtoint(str + 1, 10, &level))
 		return -EINVAL;
 
+	/* f2fs does not support negative compress level now */
+	if (level < 0) {
+		f2fs_info(sbi, "do not support negative compress level: %d", level);
+		return -ERANGE;
+	}
+
 	if (!f2fs_is_compress_level_valid(COMPRESS_ZSTD, level)) {
 		f2fs_info(sbi, "invalid zstd compress level: %d", level);
 		return -EINVAL;