5.4-stable review patch. If anyone has any objections, please let me know.
------------------
From: Gou Hao gouhao@uniontech.com
[ Upstream commit af90a8f4a09ec4a3de20142e37f37205d4687f28 ]
Check 'ix' before it is used.
Fixes: 80e675f906db ("ext4: optimize memmmove lengths in extent/index insertions") Signed-off-by: Gou Hao gouhao@uniontech.com Link: https://lore.kernel.org/r/20230906013341.7199-1-gouhao@uniontech.com Signed-off-by: Theodore Ts'o tytso@mit.edu Signed-off-by: Sasha Levin sashal@kernel.org --- fs/ext4/extents.c | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-)
diff --git a/fs/ext4/extents.c b/fs/ext4/extents.c index 478c35d453784..98e1b1ddb4ec7 100644 --- a/fs/ext4/extents.c +++ b/fs/ext4/extents.c @@ -1036,6 +1036,11 @@ static int ext4_ext_insert_index(handle_t *handle, struct inode *inode, ix = curp->p_idx; }
+ if (unlikely(ix > EXT_MAX_INDEX(curp->p_hdr))) { + EXT4_ERROR_INODE(inode, "ix > EXT_MAX_INDEX!"); + return -EFSCORRUPTED; + } + len = EXT_LAST_INDEX(curp->p_hdr) - ix + 1; BUG_ON(len < 0); if (len > 0) { @@ -1045,11 +1050,6 @@ static int ext4_ext_insert_index(handle_t *handle, struct inode *inode, memmove(ix + 1, ix, len * sizeof(struct ext4_extent_idx)); }
- if (unlikely(ix > EXT_MAX_INDEX(curp->p_hdr))) { - EXT4_ERROR_INODE(inode, "ix > EXT_MAX_INDEX!"); - return -EFSCORRUPTED; - } - ix->ei_block = cpu_to_le32(logical); ext4_idx_store_pblock(ix, ptr); le16_add_cpu(&curp->p_hdr->eh_entries, 1);