[PATCH v2] ext4: fix journal credit check when setting fscrypt context

Simon Weber
2026-02-07T10:05:19Z

Fix an issue arising when ext4 features has_journal, ea_inode, and encrypt
are activated simultaneously, leading to ENOSPC when creating an encrypted
file.

Fix by passing XATTR_CREATE flag to xattr_set_handle function if a handle
is specified, i.e., when the function is called in the control flow of
creating a new inode. This aligns the number of jbd2 credits set_handle
checks for with the number allocated for creating a new inode.

ext4_set_context must not be called with a non-null handle (fs_data) if
fscrypt context xattr is not guaranteed to not exist yet. The only other
usage of this function currently is when handling the ioctl
FS_IOC_SET_ENCRYPTION_POLICY, which calls it with fs_data=NULL.

Fixes: c1a5d5f6ab21eb7e ("ext4: improve journal credit handling in set xattr paths")

Co-developed-by: Anthony Durrer <anthonydev@fastmail.com>
Signed-off-by: Anthony Durrer <anthonydev@fastmail.com>
Signed-off-by: Simon Weber <simon.weber.39@gmail.com>

---
fs/ext4/crypto.c | 7 ++++++-
1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/fs/ext4/crypto.c b/fs/ext4/crypto.c
index cf0a0970c095..a89a14dffa48 100644
--- a/fs/ext4/crypto.c
+++ b/fs/ext4/crypto.c
@@ -163,10 +163,15 @@ static int ext4_set_context(struct inode *inode, const void *ctx, size_t len,
*/

if (handle) {
+ /*
+ * Since the inode is new it is ok to pass the XATTR_CREATE flag. This
+ * is necessary to match the reamining journal credits check in the
+ * set_handle function with the credits allocated for the new inode.
+ */
res = ext4_xattr_set_handle(handle, inode,
EXT4_XATTR_INDEX_ENCRYPTION,
EXT4_XATTR_NAME_ENCRYPTION_CONTEXT,
- ctx, len, 0);
+ ctx, len, XATTR_CREATE);
if (!res) {
ext4_set_inode_flag(inode, EXT4_INODE_ENCRYPT);
ext4_clear_inode_state(inode,
--
2.49.0