diff mbox series

[33/37] scsi: storvsc: use 16-bits defined sense codes

Message ID 20260831020451.585944-34-dlemoal@kernel.org
State New
Headers show
Series Use defined 16-bits ASC/ASCQ combinations | expand

Commit Message

Damien Le Moal Aug. 31, 2026, 2:04 a.m. UTC
Refactor the storvsc driver to use the 16-bits sense_code field of
struct scsi_sense_hdr and replace all hard-coded additional sense codes
and additional sense code qualifiers with the enum values defined in
include/scsi/scsi_sense.h. This helps with code clarity as the sense codes
being processed are easier to test and self-documented.

No functional change intended.

Signed-off-by: Damien Le Moal <dlemoal@kernel.org>
---
 drivers/scsi/storvsc_drv.c | 15 +++++++++------
 1 file changed, 9 insertions(+), 6 deletions(-)

Comments

sashiko-bot@kernel.org Aug. 31, 2026, 2:27 a.m. UTC | #1
Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:

Pre-existing issues:
- [High] Use-After-Free when an asynchronous I/O completion enqueues work onto a destroyed workqueue during device removal.
--

commit d0f50a340823cdbe80b900f5e21694a095dae714
Author: Damien Le Moal <dlemoal@kernel.org>

scsi: storvsc: use 16-bits defined sense codes

This refactors the storvsc driver to use the 16-bits sense_code field of
struct scsi_sense_hdr. It replaces hard-coded additional sense codes with
the enum values defined in include/scsi/scsi_sense.h to improve code
clarity.

> diff --git a/drivers/scsi/storvsc_drv.c b/drivers/scsi/storvsc_drv.c
> index ef3cd3bc7390e..625db97d1a03e 100644
> --- a/drivers/scsi/storvsc_drv.c
> +++ b/drivers/scsi/storvsc_drv.c
[ ... ]
> @@ -1033,7 +1033,7 @@ static void storvsc_handle_error(struct vmscsi_request *vm_srb,
>  	case SRB_STATUS_DATA_OVERRUN:
>  		if (vm_srb->srb_status & SRB_STATUS_AUTOSENSE_VALID) {
>  			/* Check for capacity change */
> -			if ((asc == 0x2a) && (ascq == 0x9)) {
> +			if (sshdr->sense_code == CAPACITY_DATA_HAS_CHANGED) {
>  				process_err_fn = storvsc_device_scan;
>  				/* Retry the I/O that triggered this. */
>  				set_host_byte(scmnd, DID_REQUEUE);
>  				goto do_work;

[Severity: High]
This isn't a bug introduced by this patch, but can this lead to a
use-after-free during device removal?

In storvsc_remove(), the driver destroys the workqueue before stopping the
VMBus channel and draining outstanding requests:

drivers/scsi/storvsc_drv.c:storvsc_remove() {
    ...
    destroy_workqueue(host_dev->handle_error_wq);
    scsi_remove_host(host);
    storvsc_dev_remove(dev);
    ...
}

If an asynchronous I/O completion indicating a capacity change arrives after
this point, it will call storvsc_handle_error(), take this goto do_work
path, and blindly enqueue work onto the destroyed workqueue:

drivers/scsi/storvsc_drv.c:storvsc_handle_error() {
    ...
do_work:
    ...
    queue_work(host_dev->handle_error_wq, &wrk->work);
}

>  			}
[ ... ]
diff mbox series

Patch

diff --git a/drivers/scsi/storvsc_drv.c b/drivers/scsi/storvsc_drv.c
index ef3cd3bc7390..625db97d1a03 100644
--- a/drivers/scsi/storvsc_drv.c
+++ b/drivers/scsi/storvsc_drv.c
@@ -1016,7 +1016,7 @@  static int storvsc_channel_init(struct hv_device *device, bool is_fc)
 static void storvsc_handle_error(struct vmscsi_request *vm_srb,
 				struct scsi_cmnd *scmnd,
 				struct Scsi_Host *host,
-				u8 asc, u8 ascq)
+				struct scsi_sense_hdr *sshdr)
 {
 	struct storvsc_scan_work *wrk;
 	void (*process_err_fn)(struct work_struct *work);
@@ -1033,7 +1033,7 @@  static void storvsc_handle_error(struct vmscsi_request *vm_srb,
 	case SRB_STATUS_DATA_OVERRUN:
 		if (vm_srb->srb_status & SRB_STATUS_AUTOSENSE_VALID) {
 			/* Check for capacity change */
-			if ((asc == 0x2a) && (ascq == 0x9)) {
+			if (sshdr->sense_code == CAPACITY_DATA_HAS_CHANGED) {
 				process_err_fn = storvsc_device_scan;
 				/* Retry the I/O that triggered this. */
 				set_host_byte(scmnd, DID_REQUEUE);
@@ -1049,8 +1049,12 @@  static void storvsc_handle_error(struct vmscsi_request *vm_srb,
 			 * want scsi_report_sense() to output a message
 			 * that a sysadmin wouldn't know what to do with.
 			 */
-			if ((asc == 0x3f) && (ascq != 0x03) &&
-					(ascq != 0x0e)) {
+			if (scsi_sense_asc(sshdr) ==
+			    ASC_TARGET_OPERATING_CONDITIONS_HAVE_CHANGED &&
+			    sshdr->sense_code !=
+			    INQUIRY_DATA_HAS_CHANGED &&
+			    sshdr->sense_code !=
+			    REPORTED_LUNS_DATA_HAS_CHANGED) {
 				process_err_fn = storvsc_device_scan;
 				set_host_byte(scmnd, DID_REQUEUE);
 				goto do_work;
@@ -1141,8 +1145,7 @@  static void storvsc_command_completion(struct storvsc_cmd_request *cmd_request,
 	}
 
 	if (vm_srb->srb_status != SRB_STATUS_SUCCESS) {
-		storvsc_handle_error(vm_srb, scmnd, host, sense_hdr.asc,
-					 sense_hdr.ascq);
+		storvsc_handle_error(vm_srb, scmnd, host, &sense_hdr);
 		/*
 		 * The Windows driver set data_transfer_length on
 		 * SRB_STATUS_DATA_OVERRUN. On other errors, this value