Re: [syzbot] [ext4?] INFO: task hung in filename_rmdir

From: Edward Adam Davis

Date: Thu Mar 05 2026 - 07:26:11 EST


#syz test

diff --git a/fs/ext4/extents.c b/fs/ext4/extents.c
index ae3804f36535..56b7398a0b40 100644
--- a/fs/ext4/extents.c
+++ b/fs/ext4/extents.c
@@ -4457,20 +4457,19 @@ int ext4_ext_map_blocks(handle_t *handle, struct inode *inode,
path = ext4_ext_insert_extent(handle, inode, path, &newex, flags);
if (IS_ERR(path)) {
err = PTR_ERR(path);
- if (allocated_clusters) {
- int fb_flags = 0;
-
+ /*
+ * Gracefully handle out of space conditions. If the filesystem
+ * is inconsistent, we'll just leak allocated blocks to avoid
+ * causing even more damage.
+ */
+ if (allocated_clusters && (err == -EDQUOT || err == -ENOSPC)) {
/*
* free data blocks we just allocated.
* not a good idea to call discard here directly,
* but otherwise we'd need to call it every free().
*/
ext4_discard_preallocations(inode);
- if (flags & EXT4_GET_BLOCKS_DELALLOC_RESERVE)
- fb_flags = EXT4_FREE_BLOCKS_NO_QUOT_UPDATE;
- ext4_free_blocks(handle, inode, NULL, newblock,
- EXT4_C2B(sbi, allocated_clusters),
- fb_flags);
+ ext4_ext_remove_space(inode, newex.ee_block, newex.ee_block);
}
goto out;
}