From 83c68bbcb6ac2dbbcaf12e2281a29a9f73b97d0f Mon Sep 17 00:00:00 2001 From: Su Yue Date: Thu, 11 Feb 2021 16:38:28 +0800 Subject: [PATCH] btrfs: initialize fs_info::csum_size earlier in open_ctree User reported that btrfs-progs misc-tests/028-superblock-recover fails: [TEST/misc] 028-superblock-recover unexpected success: mounted fs with corrupted superblock test failed for case 028-superblock-recover The test case expects that a broken image with bad superblock will be rejected to be mounted. However, the test image just passed csum check of superblock and was successfully mounted. Commit 55fc29bed8dd ("btrfs: use cached value of fs_info::csum_size everywhere") replaces all calls to btrfs_super_csum_size by fs_info::csum_size. The calls include the place where fs_info->csum_size is not initialized. So btrfs_check_super_csum() passes because memcmp() with len 0 always returns 0. Fix it by caching csum size in btrfs_fs_info::csum_size once we know the csum type in superblock is valid in open_ctree(). Link: https://github.com/kdave/btrfs-progs/issues/250 Fixes: 55fc29bed8dd ("btrfs: use cached value of fs_info::csum_size everywhere") Signed-off-by: Su Yue Reviewed-by: David Sterba Signed-off-by: David Sterba --- fs/btrfs/disk-io.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c index 6b35b7e88136..07a2b4f69b10 100644 --- a/fs/btrfs/disk-io.c +++ b/fs/btrfs/disk-io.c @@ -3044,6 +3044,8 @@ int __cold open_ctree(struct super_block *sb, struct btrfs_fs_devices *fs_device goto fail_alloc; } + fs_info->csum_size = btrfs_super_csum_size(disk_super); + ret = btrfs_init_csum_hash(fs_info, csum_type); if (ret) { err = ret; @@ -3161,7 +3163,6 @@ int __cold open_ctree(struct super_block *sb, struct btrfs_fs_devices *fs_device fs_info->nodesize = nodesize; fs_info->sectorsize = sectorsize; fs_info->sectorsize_bits = ilog2(sectorsize); - fs_info->csum_size = btrfs_super_csum_size(disk_super); fs_info->csums_per_leaf = BTRFS_MAX_ITEM_SIZE(fs_info) / fs_info->csum_size; fs_info->stripesize = stripesize;