Re: [PATCH] ext4: return -EINVAL on hole in ext4_convert_unwritten_extents_atomic()
From: Zhang Yi
Date: Fri Oct 23 2026 - 21:54:10 EST
On 10/23/2026 6:23 PM, Ojaswin Mujoo wrote:
We should ideally never encounter a hole during the endio conversion as
that indicates something is wrong with our extent handling. Still if we do
find a hole at atomic write endio, ext4_map_blocks() returns 0 which would
be returned back to callers by ext4_convert_unwritten_extents_atomic().
This can be wrongly interpreted as a success. Fix this by bailing out with
-EINVAL instead.
Signed-off-by: Ojaswin Mujoo <ojaswin@xxxxxxxxxxxxx>
Ha, this looks good to me, thanks!
Reviewed-by: Zhang Yi <yi.zhang@xxxxxxxxxx>
---
fs/ext4/extents.c | 8 ++++++++
1 file changed, 8 insertions(+)
diff --git a/fs/ext4/extents.c b/fs/ext4/extents.c
index 7193429a05e1..b54d8227786b 100644
--- a/fs/ext4/extents.c
+++ b/fs/ext4/extents.c
@@ -5107,6 +5107,14 @@ int ext4_convert_unwritten_extents_atomic(handle_t *handle, struct inode *inode,
map.m_lblk += ret;
map.m_len = (max_blocks -= ret);
ret = ext4_map_blocks(handle, inode, &map, flags);
+ if (ret == 0) {
+ ext4_msg(inode->i_sb, KERN_ERR,
+ "inode #%llu: block %u: len %u: "
+ "hole found while converting extents for atomic write",
+ inode->i_ino, map.m_lblk, map.m_len);
+ ret = -EINVAL;
+ break;
+ }
if (ret != max_blocks)
ext4_msg(inode->i_sb, KERN_INFO,
"inode #%llu: block %u: len %u: "
---
base-commit: 8c4f6e3376348fc3162eed86a05b933921c8f9ed
change-id: 20261023-ext4-atomic-endio-fix-b4-9e1ead9e1aca
Best regards,