From 979409e6f4590e881b0eee29aab8f22f8047c91c Mon Sep 17 00:00:00 2001 From: Anand Jain Date: Tue, 2 Apr 2019 18:07:38 +0800 Subject: [PATCH] btrfs: prop: fix zstd compression parameter validation commit 50398fde997f6be8faebdb5f38e9c9c467370f51 upstream. We let pass zstd compression parameter even if it is not fully valid. For example: $ btrfs prop set /btrfs compression zst $ btrfs prop get /btrfs compression compression=zst zlib and lzo are fine. Fix it by checking the correct prefix length. Fixes: 5c1aab1dd544 ("btrfs: Add zstd support") CC: stable@vger.kernel.org # 4.14+ Reviewed-by: Nikolay Borisov Signed-off-by: Anand Jain Reviewed-by: David Sterba Signed-off-by: David Sterba Signed-off-by: Greg Kroah-Hartman --- fs/btrfs/props.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/fs/btrfs/props.c b/fs/btrfs/props.c index cbabc6f2b322..3eee2f7e1dd2 100644 --- a/fs/btrfs/props.c +++ b/fs/btrfs/props.c @@ -416,7 +416,7 @@ static int prop_compression_apply(struct inode *inode, btrfs_set_fs_incompat(fs_info, COMPRESS_LZO); } else if (!strncmp("zlib", value, 4)) { type = BTRFS_COMPRESS_ZLIB; - } else if (!strncmp("zstd", value, len)) { + } else if (!strncmp("zstd", value, 4)) { type = BTRFS_COMPRESS_ZSTD; btrfs_set_fs_incompat(fs_info, COMPRESS_ZSTD); } else { -- 2.20.1