Re: [patch] [SCSI] scsi_transport_sas: check for allocation failure

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On 13-03-08 05:50 PM, James Bottomley wrote:
On Fri, 2013-03-08 at 12:57 -0500, Douglas Gilbert wrote:
On 13-03-08 07:02 AM, Dan Carpenter wrote:
Static checkers complain that this allocation isn't checked.  We
should return zero if the allocation fails.

Signed-off-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>

diff --git a/drivers/scsi/scsi_transport_sas.c b/drivers/scsi/scsi_transport_sas.c
index 1b68142..a022997 100644
--- a/drivers/scsi/scsi_transport_sas.c
+++ b/drivers/scsi/scsi_transport_sas.c
@@ -379,9 +379,12 @@ sas_tlr_supported(struct scsi_device *sdev)
   {
   	const int vpd_len = 32;
   	struct sas_end_device *rdev = sas_sdev_to_rdev(sdev);
-	char *buffer = kzalloc(vpd_len, GFP_KERNEL);
+	char *buffer;
   	int ret = 0;

+	buffer = kzalloc(vpd_len, GFP_KERNEL);
+	if (!buffer)
+		goto out;
   	if (scsi_get_vpd_page(sdev, 0x90, buffer, vpd_len))
   		goto out;


For 32 bytes, why not use the stack?

Because the buffer is a DMA target.  You can't DMA to stack because of
padding and cacheline issues.

And I went to the definition of scsi_get_vpd_page()
to see if that was called out in the header comments.
Guess what ... and those same header comments talked
about freeing a returned pointer. It needs to be
cleaned up, IMO.

Doug Gilbert

/**
 * scsi_get_vpd_page - Get Vital Product Data from a SCSI device
 * @sdev: The device to ask
 * @page: Which Vital Product Data to return
 * @buf: where to store the VPD
 * @buf_len: number of bytes in the VPD buffer area
 *
 * SCSI devices may optionally supply Vital Product Data.  Each 'page'
 * of VPD is defined in the appropriate SCSI document (eg SPC, SBC).
 * If the device supports this VPD page, this routine returns a pointer
 * to a buffer containing the data from that page.  The caller is
 * responsible for calling kfree() on this pointer when it is no longer
 * needed.  If we cannot retrieve the VPD page this routine returns %NULL.
 */
int scsi_get_vpd_page(struct scsi_device *sdev, u8 page, unsigned char *buf,
                      int buf_len)


--
To unsubscribe from this list: send the line "unsubscribe kernel-janitors" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html


[Index of Archives]     [Kernel Development]     [Kernel Announce]     [Kernel Newbies]     [Linux Networking Development]     [Share Photos]     [IDE]     [Security]     [Git]     [Netfilter]     [Yosemite News]     [MIPS Linux]     [ARM Linux]     [Device Mapper]

  Powered by Linux