[PATCH v2 0/5] scsi: ufs: Fix UIC result byte and BSG request handling

[Stanley Jhu <stanleyjhu@google.com>]

ufs-bsg fixes for issues found by fuzzing /dev/bsg/ufs-bsg* with
syzkaller on QEMU's emulated UFS host controller and in review of v1,
plus a fix for peer DME retries.

Patch 1 completes failed BSG requests via bsg_job_done() so error paths
do not leak the job's device reference and mapped scatterlists.
Patch 2 clears the reused reply buffer so replies do not carry bytes
from an earlier request.
Patch 3 rejects requests shorter than the UFS BSG request structures.
Patch 4 rejects UIC commands with a non-zero result byte from userspace.
Patch 5 clears the stale UIC result byte and restores argument3 before
peer DME retries.

Patches 1-2 also address the sashiko review of the bsg reply_len patch:
https://lore.kernel.org/all/sashiko-outbox-169843@kernel.org/

Tested on QEMU arm64: the reproducers no longer trigger.

Differences from v1:
- New patch 1/5: complete failed jobs via bsg_job_done().
- New patch 2/5: clear the reply buffer on entry.
- Patch 4/5: reject non-zero UIC result byte with -EINVAL (Bart).
- Patch 5/5: restore argument3 on each retry in ufshcd_dme_set_attr().

Link: https://lore.kernel.org/all/20261013102913.948718-1-stanleyjhu@google.com/

Stanley Jhu (5):
  scsi: ufs: bsg: Complete the job on error
  scsi: ufs: bsg: Clear the reply buffer before use
  scsi: ufs: bsg: Validate request_len before accessing request
  scsi: ufs: bsg: Reject UIC commands with a non-zero result byte
  scsi: ufs: core: Clear stale UIC result byte before peer DME retries

 drivers/ufs/core/ufs_bsg.c | 23 +++++++++++++++++------
 drivers/ufs/core/ufshcd.c  |  9 +++++++--
 2 files changed, 24 insertions(+), 8 deletions(-)

base-commit: 9621cbd332862eb6651e2aba24ed18f66560de66
-- 
2.56.0.385.gd3acb90ef8-goog