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[LTS 9.2] ext4: fix double-free of blocks due to wrong extents moved_len #426

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Merged
merged 1 commit into from
Jul 19, 2025
Merged

[LTS 9.2] ext4: fix double-free of blocks due to wrong extents moved_len #426

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6 changes: 2 additions & 4 deletions fs/ext4/move_extent.c
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Original file line number Diff line number Diff line change
Expand Up @@ -615,6 +615,7 @@ ext4_move_extents(struct file *o_filp, struct file *d_filp, __u64 orig_blk,
goto out;
o_end = o_start + len;

*moved_len = 0;
while (o_start < o_end) {
struct ext4_extent *ex;
ext4_lblk_t cur_blk, next_blk;
Expand Down Expand Up @@ -669,7 +670,7 @@ ext4_move_extents(struct file *o_filp, struct file *d_filp, __u64 orig_blk,
*/
ext4_double_up_write_data_sem(orig_inode, donor_inode);
/* Swap original branches with new branches */
move_extent_per_page(o_filp, donor_inode,
*moved_len += move_extent_per_page(o_filp, donor_inode,
orig_page_index, donor_page_index,
offset_in_page, cur_len,
unwritten, &ret);
Expand All @@ -679,9 +680,6 @@ ext4_move_extents(struct file *o_filp, struct file *d_filp, __u64 orig_blk,
o_start += cur_len;
d_start += cur_len;
}
*moved_len = o_start - orig_blk;
if (*moved_len > len)
*moved_len = len;

out:
if (*moved_len) {
Expand Down