@@ -476,8 +476,14 @@ static int ext2_create_symlink(struct btrfs_trans_handle *trans,
int ret;
char *pathname;
u64 inode_size = btrfs_stack_inode_size(btrfs_inode);
+
if (ext2fs_inode_data_blocks2(ext2_fs, ext2_inode)) {
- btrfs_set_stack_inode_size(btrfs_inode, inode_size + 1);
+ if (inode_size >= trans->fs_info->sectorsize) {
+ error("inode size too large for symbol link, has %llu expect [1, %u]",
+ inode_size, trans->fs_info->sectorsize - 1);
+ return -EUCLEAN;
+ }
+ btrfs_set_stack_inode_size(btrfs_inode, inode_size);
ret = ext2_create_file_extents(trans, root, objectid,
btrfs_inode, ext2_fs, ext2_ino,
CONVERT_FLAG_DATACSUM |
@@ -489,8 +495,8 @@ static int ext2_create_symlink(struct btrfs_trans_handle *trans,
pathname = (char *)&(ext2_inode->i_block[0]);
BUG_ON(pathname[inode_size] != 0);
ret = btrfs_insert_inline_extent(trans, root, objectid, 0,
- pathname, inode_size + 1);
- btrfs_set_stack_inode_nbytes(btrfs_inode, inode_size + 1);
+ pathname, inode_size);
+ btrfs_set_stack_inode_nbytes(btrfs_inode, inode_size);
return ret;
}
@@ -538,8 +538,8 @@ static int reiserfs_copy_symlink(struct btrfs_trans_handle *trans,
len = get_ih_item_len(tp_item_head(&path));
ret = btrfs_insert_inline_extent(trans, root, objectid, 0,
- symlink, len + 1);
- btrfs_set_stack_inode_nbytes(btrfs_inode, len + 1);
+ symlink, len);
+ btrfs_set_stack_inode_nbytes(btrfs_inode, len);
fail:
pathrelse(&path);
return ret;
@@ -26,6 +26,7 @@
#include "kernel-shared/extent_io.h"
#include "kernel-shared/uapi/btrfs.h"
#include "common/internal.h"
+#include "common/messages.h"
#define MAX_CSUM_ITEMS(r, size) ((((BTRFS_LEAF_DATA_SIZE(r->fs_info) - \
sizeof(struct btrfs_item) * 2) / \
@@ -97,6 +98,8 @@ int btrfs_insert_inline_extent(struct btrfs_trans_handle *trans,
int err = 0;
int ret;
+ UASSERT(size < trans->fs_info->sectorsize);
+
path = btrfs_alloc_path();
if (!path)
return -ENOMEM;
[BUG] Sometimes test case btrfs/012 fails randomly, with the failure to read a softlink: QA output created by 012 Checking converted btrfs against the original one: -OK +readlink: Structure needs cleaning Checking saved ext2 image against the original one: OK Furthermore, this will trigger a kernel error message: BTRFS critical (device dm-2): regular/prealloc extent found for non-regular inode 133081 [CAUSE] For that specific inode 133081, the tree dump looks like this: item 127 key (133081 INODE_ITEM 0) itemoff 40984 itemsize 160 generation 1 transid 1 size 4095 nbytes 4096 block group 0 mode 120777 links 1 uid 0 gid 0 rdev 0 sequence 0 flags 0x0(none) item 128 key (133081 INODE_REF 133080) itemoff 40972 itemsize 12 index 2 namelen 2 name: l3 item 129 key (133081 EXTENT_DATA 0) itemoff 40919 itemsize 53 generation 4 type 1 (regular) extent data disk byte 2147483648 nr 38080512 extent data offset 37974016 nr 4096 ram 38080512 extent compression 0 (none) Note that, the soft link inode size is 4095, just one by smaller than the sector size, but its nbytes is 4096, larger than the upper limit of inline extent. Thus it results the creation of a regular extent, but for btrfs we do not accept a soft link with a regular/preallocated extent, thus kernel rejects such read and failed the readlink call. The root cause is in the convert code, where for soft links we always create a data extent with its size + 1, causing the above problem. I guess the original code is to handle the terminating NUL, but in btrfs we never need to bother terminating NUL for inline extents. Thus this pitfall in btrfs-convert leads to the above invalid data extent and fail the test case. [FIX] Fix the corner case by removing the terminating NUL when inserting an inline extent. Furthermore, to prevent such problem from happening again, do extra UASSERT() for btrfs_insert_inline_extent() to detect such problem. Signed-off-by: Qu Wenruo <wqu@suse.com> --- convert/source-ext2.c | 12 +++++++++--- convert/source-reiserfs.c | 4 ++-- kernel-shared/file-item.c | 3 +++ 3 files changed, 14 insertions(+), 5 deletions(-)