4.14-stable review patch. If anyone has any objections, please let me know.
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commit 7f43d4affb2a254d421ab20b0cf65ac2569909fb upstream.
Function check_leaf() checks if any item pointer points outside of the leaf, but it doesn't check if the pointer overlaps with the item itself.
Normally only the last item may be the victim, but adding such check is never a bad idea anyway.
Signed-off-by: Qu Wenruo quwenruo.btrfs@gmx.com Reviewed-by: Nikolay Borisov nborisov@suse.com Reviewed-by: David Sterba dsterba@suse.com Signed-off-by: David Sterba dsterba@suse.com Signed-off-by: Ben Hutchings ben.hutchings@codethink.co.uk Signed-off-by: Sasha Levin sashal@kernel.org --- fs/btrfs/disk-io.c | 7 +++++++ 1 file changed, 7 insertions(+)
diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c index 4a1e63df1183..da7b2039e4cb 100644 --- a/fs/btrfs/disk-io.c +++ b/fs/btrfs/disk-io.c @@ -644,6 +644,13 @@ static noinline int check_leaf(struct btrfs_root *root, return -EUCLEAN; }
+ /* Also check if the item pointer overlaps with btrfs item. */ + if (btrfs_item_nr_offset(slot) + sizeof(struct btrfs_item) > + btrfs_item_ptr_offset(leaf, slot)) { + CORRUPT("slot overlap with its data", leaf, root, slot); + return -EUCLEAN; + } + prev_key.objectid = key.objectid; prev_key.type = key.type; prev_key.offset = key.offset;