diff options
| author | Bodo Stroesser <bostroesser@gmail.com> | 2021-10-13 19:16:06 +0200 |
|---|---|---|
| committer | Martin K. Petersen <martin.petersen@oracle.com> | 2021-10-18 22:38:35 -0400 |
| commit | 1d2ac7b69d6a984d0f58b82d0f658ebd9aa05428 (patch) | |
| tree | c91cb46bd1cc51c2a1af64732e2e230bba800993 | |
| parent | d1e51ea6bf5f72f67937f4446a5b6d56330f9d79 (diff) | |
scsi: target: tcmu: Allocate zeroed pages for data area
Tcmu populates the data area (used for communication with userspace) with
pages that are allocated by calling alloc_page(GFP_NOIO). Therefore
previous content of the allocated pages is exposed to user space. Avoid
this by adding __GFP_ZERO flag.
Zeroing the pages does (nearly) not affect tcmu throughput, because
allocated pages are re-used for the data transfers of later SCSI cmds.
Link: https://lore.kernel.org/r/20211013171606.25197-1-bostroesser@gmail.com
Signed-off-by: Bodo Stroesser <bostroesser@gmail.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
| -rw-r--r-- | drivers/target/target_core_user.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/drivers/target/target_core_user.c b/drivers/target/target_core_user.c index dc220fad06fa..7b2a89a67cdb 100644 --- a/drivers/target/target_core_user.c +++ b/drivers/target/target_core_user.c @@ -523,8 +523,8 @@ static inline int tcmu_get_empty_block(struct tcmu_dev *udev, rcu_read_unlock(); for (i = cnt; i < page_cnt; i++) { - /* try to get new page from the mm */ - page = alloc_page(GFP_NOIO); + /* try to get new zeroed page from the mm */ + page = alloc_page(GFP_NOIO | __GFP_ZERO); if (!page) break; |