scsi: storvsc: Ratelimit warning logs to prevent VM denial of service
commit d2138eab8cde61e0e6f62d0713e45202e8457d6d upstream.
If there's a persistent error in the hypervisor, the SCSI warning for
failed I/O can flood the kernel log and max out CPU utilization,
preventing troubleshooting from the VM side. Ratelimit the warning so
it doesn't DoS the VM.
BUG=b/398408265
TEST=presubmit
RELEASE_NOTE=Fixed CVE-2025-21690 in the Linux kernel.
cos-patch: security-moderate
Closes: https://github.com/microsoft/WSL/issues/9173
Change-Id: I6b1b28482e1364b0827e82e601d01ce5252480d5
Signed-off-by: Easwar Hariharan <eahariha@linux.microsoft.com>
Link: https://lore.kernel.org/r/20250107-eahariha-ratelimit-storvsc-v1-1-7fc193d1f2b0@linux.microsoft.com
Reviewed-by: Michael Kelley <mhklinux@outlook.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Kernel CVE Triage Automation <cloud-image-kernel-cve-triage-automation@prod.google.com>
Reviewed-on: https://cos-review.googlesource.com/c/third_party/kernel/+/93899
Reviewed-by: Shuo Yang <gshuoy@google.com>
Reviewed-by: Kevin Berry <kpberry@google.com>
Tested-by: Cusky Presubmit Bot <presubmit@cos-infra-prod.iam.gserviceaccount.com>
diff --git a/drivers/scsi/storvsc_drv.c b/drivers/scsi/storvsc_drv.c
index 0685cbe..d47adab 100644
--- a/drivers/scsi/storvsc_drv.c
+++ b/drivers/scsi/storvsc_drv.c
@@ -171,6 +171,12 @@ do { \
dev_warn(&(dev)->device, fmt, ##__VA_ARGS__); \
} while (0)
+#define storvsc_log_ratelimited(dev, level, fmt, ...) \
+do { \
+ if (do_logging(level)) \
+ dev_warn_ratelimited(&(dev)->device, fmt, ##__VA_ARGS__); \
+} while (0)
+
struct vmscsi_request {
u16 length;
u8 srb_status;
@@ -1168,7 +1174,7 @@ static void storvsc_on_io_completion(struct storvsc_device *stor_device,
int loglevel = (stor_pkt->vm_srb.cdb[0] == TEST_UNIT_READY) ?
STORVSC_LOGGING_WARN : STORVSC_LOGGING_ERROR;
- storvsc_log(device, loglevel,
+ storvsc_log_ratelimited(device, loglevel,
"tag#%d cmd 0x%x status: scsi 0x%x srb 0x%x hv 0x%x\n",
scsi_cmd_to_rq(request->cmd)->tag,
stor_pkt->vm_srb.cdb[0],
