Commit 7e1b150f authored by Chao Yu's avatar Chao Yu Committed by Jaegeuk Kim
Browse files

f2fs: compress: fix to avoid redundant compress extension 



With below script, redundant compress extension will be parsed and added
by parse_options(), because parse_options() doesn't check whether the
extension is existed or not, fix it.

1. mount -t f2fs -o compress_extension=so /dev/vdb /mnt/f2fs
2. mount -t f2fs -o remount,compress_extension=so /mnt/f2fs
3. mount|grep f2fs

/dev/vdb on /mnt/f2fs type f2fs (...,compress_extension=so,compress_extension=so,...)

Fixes: 4c8ff709 ("f2fs: support data compression")
Fixes: 151b1982 ("f2fs: compress: add nocompress extensions support")
Signed-off-by: default avatarChao Yu <chao@kernel.org>
Signed-off-by: default avatarJaegeuk Kim <jaegeuk@kernel.org>
parent 2aaea533

fs/f2fs/super.c

+33 −0
Original line number Diff line number Diff line
@@ -547,6 +547,29 @@ static int f2fs_set_test_dummy_encryption(struct super_block *sb, 
}



#ifdef CONFIG_F2FS_FS_COMPRESSION

static bool is_compress_extension_exist(struct f2fs_sb_info *sbi,

					const char *new_ext, bool is_ext)

{

	unsigned char (*ext)[F2FS_EXTENSION_LEN];

	int ext_cnt;

	int i;



	if (is_ext) {

		ext = F2FS_OPTION(sbi).extensions;

		ext_cnt = F2FS_OPTION(sbi).compress_ext_cnt;

	} else {

		ext = F2FS_OPTION(sbi).noextensions;

		ext_cnt = F2FS_OPTION(sbi).nocompress_ext_cnt;

	}



	for (i = 0; i < ext_cnt; i++) {

		if (!strcasecmp(new_ext, ext[i]))

			return true;

	}



	return false;

}



/*

 * 1. The same extension name cannot not appear in both compress and non-compress extension

 * at the same time.
@@ -1149,6 +1172,11 @@ static int parse_options(struct super_block *sb, char *options, bool is_remount) 
				return -EINVAL;

			}



			if (is_compress_extension_exist(sbi, name, true)) {

				kfree(name);

				break;

			}



			strcpy(ext[ext_cnt], name);

			F2FS_OPTION(sbi).compress_ext_cnt++;

			kfree(name);
@@ -1173,6 +1201,11 @@ static int parse_options(struct super_block *sb, char *options, bool is_remount) 
				return -EINVAL;

			}



			if (is_compress_extension_exist(sbi, name, false)) {

				kfree(name);

				break;

			}



			strcpy(noext[noext_cnt], name);

			F2FS_OPTION(sbi).nocompress_ext_cnt++;

			kfree(name);