[PATCH 0/2] BTRFS_IOC_INO_LOOKUP ioctl fixes

[PATCH 0/2] BTRFS_IOC_INO_LOOKUP ioctl fixes

[Filipe David Borba Manana]

This set of patches fixes 2 issues with the BTRFS_IOC_INO_LOOKUP ioctl:

1) missing error code return when path is too long;
2) ocassional ENOENT error even when the desired inode ref items exist.

Filipe David Borba Manana (2):
  Btrfs: add missing error code to BTRFS_IOC_INO_LOOKUP handler
  Btrfs: don't miss inode ref items in BTRFS_IOC_INO_LOOKUP

 fs/btrfs/ioctl.c |   24 +++++++++++++-----------
 1 file changed, 13 insertions(+), 11 deletions(-)

-- 
1.7.9.5

[PATCH 1/2] Btrfs: add missing error code to BTRFS_IOC_INO_LOOKUP handler

[Filipe David Borba Manana]

If the path doesn't fit in the input buffer, return ENAMETOOLONG
instead of returning with a success code (0) and a partially
filled and right justified buffer.

Also removed useless buffer pointer check outside the while loop.

Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
---
 fs/btrfs/ioctl.c |    6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c
index 2312c0f..3f2a8c1 100644
--- a/fs/btrfs/ioctl.c
+++ b/fs/btrfs/ioctl.c
@@ -2015,8 +2015,10 @@ static noinline int btrfs_search_path_in_tree(struct btrfs_fs_info *info,
 		len = btrfs_inode_ref_name_len(l, iref);
 		ptr -= len + 1;
 		total_len += len + 1;
-		if (ptr < name)
+		if (ptr < name) {
+			ret = -ENAMETOOLONG;
 			goto out;
+		}
 
 		*(ptr + len) = '/';
 		read_extent_buffer(l, ptr,(unsigned long)(iref + 1), len);
@@ -2029,8 +2031,6 @@ static noinline int btrfs_search_path_in_tree(struct btrfs_fs_info *info,
 		key.offset = (u64)-1;
 		dirid = key.objectid;
 	}
-	if (ptr < name)
-		goto out;
 	memmove(name, ptr, total_len);
 	name[total_len]='\0';
 	ret = 0;
-- 
1.7.9.5

[PATCH 2/2] Btrfs: don't miss inode ref items in BTRFS_IOC_INO_LOOKUP

[Filipe David Borba Manana]

If the inode ref key was not found and the current leaf slot
was 0 (first item in the leaf) the code would always return
-ENOENT. This was not correct because the desired inode ref
item might be the last item in the previous leaf.

Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
---
 fs/btrfs/ioctl.c |   18 ++++++++++--------
 1 file changed, 10 insertions(+), 8 deletions(-)

diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c
index 3f2a8c1..e8f295c 100644
--- a/fs/btrfs/ioctl.c
+++ b/fs/btrfs/ioctl.c
@@ -1998,19 +1998,21 @@ static noinline int btrfs_search_path_in_tree(struct btrfs_fs_info *info,
 		ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
 		if (ret < 0)
 			goto out;
+		else if (ret > 0) {
+			ret = btrfs_previous_item(root, path, dirid,
+						  BTRFS_INODE_REF_KEY);
+			if (ret < 0)
+				goto out;
+			else if (ret > 0) {
+				ret = -ENOENT;
+				goto out;
+			}
+		}
 
 		l = path->nodes[0];
 		slot = path->slots[0];
-		if (ret > 0 && slot > 0)
-			slot--;
 		btrfs_item_key_to_cpu(l, &key, slot);
 
-		if (ret > 0 && (key.objectid != dirid ||
-				key.type != BTRFS_INODE_REF_KEY)) {
-			ret = -ENOENT;
-			goto out;
-		}
-
 		iref = btrfs_item_ptr(l, slot, struct btrfs_inode_ref);
 		len = btrfs_inode_ref_name_len(l, iref);
 		ptr -= len + 1;
-- 
1.7.9.5