[PATCH 6.6 529/638] f2fs: compress: fix to check zstd compress level correctly in mount option

From: Sasha Levin
Date: Mon Mar 25 2024 - 05:12:47 EST


From: Chao Yu <chao@xxxxxxxxxx>

[ 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>
---
fs/f2fs/super.c | 10 ++++++++--
1 file changed, 8 insertions(+), 2 deletions(-)

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;
--
2.43.0