diff options
| author | David Carlier <devnexen@gmail.com> | 2026-04-15 06:23:00 +0100 |
|---|---|---|
| committer | Mike Rapoport (Microsoft) <rppt@kernel.org> | 2026-04-28 16:16:16 +0300 |
| commit | 0fb1daf0b78d0e23b63b6b65de56d4a3fd83bc14 (patch) | |
| tree | d0632444d7b847986fcb044f26ba9a966d584309 | |
| parent | a6715d7ec472a476db17787697a4abda62962284 (diff) | |
mm/memfd_luo: report error when restoring a folio fails mid-loop
memfd_luo_retrieve_folios() initialises err to -EIO, but the per-iteration
calls to mem_cgroup_charge(), shmem_add_to_page_cache() and
shmem_inode_acct_blocks() reuse and overwrite err. Once any iteration
completes successfully, err becomes zero.
If a later iteration's kho_restore_folio() returns NULL, the failure path
jumps to put_folios without resetting err, so the function returns 0.
The caller memfd_luo_retrieve() then takes the success path, sets
args->file and reports the restore as successful, leaving userspace with
a partially populated memfd and no indication that anything went wrong.
Set err to -EIO in the kho_restore_folio() failure branch so the error
is propagated to the caller.
Signed-off-by: David Carlier <devnexen@gmail.com>
Reviewed-by: Pratyush Yadav <pratyush@kernel.org>
Fixes: b3749f174d68 ("mm: memfd_luo: allow preserving memfd")
Link: https://patch.msgid.link/20260415052300.362539-1-devnexen@gmail.com
Signed-off-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
| -rw-r--r-- | mm/memfd_luo.c | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/mm/memfd_luo.c b/mm/memfd_luo.c index b02b503c750d..35d1247281e0 100644 --- a/mm/memfd_luo.c +++ b/mm/memfd_luo.c @@ -427,6 +427,7 @@ static int memfd_luo_retrieve_folios(struct file *file, if (!folio) { pr_err("Unable to restore folio at physical address: %llx\n", phys); + err = -EIO; goto put_folios; } index = pfolio->index; |