[PATCH] cxl/mbox: Fix missing variable payload checks in cmd size validation

[Vishal Verma <vishal.l.verma@intel.com>]

The conversion of command sizes to unsigned missed a couple of checks
against variable size payloads during command validation, which made all
variable payload commands unconditionally fail. Add the checks back using
the new CXL_VARIABLE_PAYLOAD scheme.

Reported-by: Abhi Cs <abhi.cs@intel.com>
Fixes: 26f89535a5bb ("cxl/mbox: Use type __u32 for mailbox payload sizes")
Cc: <stable@vger.kernel.org>
Cc: Ira Weiny <ira.weiny@intel.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Alison Schofield <alison.schofield@intel.com>
Signed-off-by: Vishal Verma <vishal.l.verma@intel.com>
---
 drivers/cxl/core/mbox.c | 10 ++++++----
 1 file changed, 6 insertions(+), 4 deletions(-)

diff --git a/drivers/cxl/core/mbox.c b/drivers/cxl/core/mbox.c
index 40e3ccb2bf3e..d929b89d12a7 100644
--- a/drivers/cxl/core/mbox.c
+++ b/drivers/cxl/core/mbox.c
@@ -355,12 +355,14 @@ static int cxl_to_mem_cmd(struct cxl_mem_command *mem_cmd,
 		return -EBUSY;
 
 	/* Check the input buffer is the expected size */
-	if (info->size_in != send_cmd->in.size)
-		return -ENOMEM;
+	if (info->size_in != CXL_VARIABLE_PAYLOAD)
+		if (info->size_in != send_cmd->in.size)
+			return -ENOMEM;
 
 	/* Check the output buffer is at least large enough */
-	if (send_cmd->out.size < info->size_out)
-		return -ENOMEM;
+	if (info->size_out != CXL_VARIABLE_PAYLOAD)
+		if (send_cmd->out.size < info->size_out)
+			return -ENOMEM;
 
 	*mem_cmd = (struct cxl_mem_command) {
 		.info = {

base-commit: 1985cf58850562e4b960e19d46f0d8f19d6c7cbd
-- 
2.36.1