ext4: fix error handling in ext4_ext_truncate()
Previously ext4_ext_truncate() was ignoring potential error returns
from ext4_es_remove_extent() and ext4_ext_remove_space(). This can
lead to the on-diks extent tree and the extent status tree cache
getting out of sync, which is particuarlly bad, and can lead to file
system corruption and potential data loss.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Cc: stable@vger.kernel.org
diff --git a/fs/ext4/extents.c b/fs/ext4/extents.c
index 7097b0f..f57cc0e 100644
--- a/fs/ext4/extents.c
+++ b/fs/ext4/extents.c
@@ -4405,9 +4405,20 @@
last_block = (inode->i_size + sb->s_blocksize - 1)
>> EXT4_BLOCK_SIZE_BITS(sb);
+retry:
err = ext4_es_remove_extent(inode, last_block,
EXT_MAX_BLOCKS - last_block);
+ if (err == ENOMEM) {
+ cond_resched();
+ congestion_wait(BLK_RW_ASYNC, HZ/50);
+ goto retry;
+ }
+ if (err) {
+ ext4_std_error(inode->i_sb, err);
+ return;
+ }
err = ext4_ext_remove_space(inode, last_block, EXT_MAX_BLOCKS - 1);
+ ext4_std_error(inode->i_sb, err);
}
static void ext4_falloc_update_inode(struct inode *inode,