From: Gou Hao <gouhao@uniontech.com> stable inclusion from stable-v4.19.299 commit 23ab419bde8cc2b378bdbf3d518b7a5542665fbe category: bugfix bugzilla: https://gitee.com/openeuler/kernel/issues/I8MCB5 CVE: NA Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=... -------------------------------- [ 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> Signed-off-by: Zhang Changzhong <zhangchangzhong@huawei.com> --- 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 6edab0ef28fd..e29b55991e8f 100644 --- a/fs/ext4/extents.c +++ b/fs/ext4/extents.c @@ -1052,6 +1052,11 @@ 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) { @@ -1061,11 +1066,6 @@ 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); -- 2.34.1