[SCSI] eliminate potential kmalloc failure in scsi_get_vpd_page()

The best way to fix this is to eliminate the intenal kmalloc() and
make the caller allocate the required amount of storage.

Signed-off-by: James Bottomley <James.Bottomley@suse.de>

1 files changed, 15 insertions, 11 deletions

diff --git a/drivers/scsi/sd.c b/drivers/scsi/sd.c
index 255da53e5a01..c5e9a99d4066 100644
--- a/drivers/scsi/sd.c
+++ b/drivers/scsi/sd.c
@@ -1946,13 +1946,13 @@ static void sd_read_block_limits(struct scsi_disk *sdkp)
 {
         struct request_queue *q = sdkp->disk->queue;
         unsigned int sector_sz = sdkp->device->sector_size;
-        char *buffer;
+        const int vpd_len = 32;
+        unsigned char *buffer = kmalloc(vpd_len, GFP_KERNEL);
 
-        /* Block Limits VPD */
-        buffer = scsi_get_vpd_page(sdkp->device, 0xb0);
-
-        if (buffer == NULL)
-                return;
+        if (!buffer ||
+            /* Block Limits VPD */
+            scsi_get_vpd_page(sdkp->device, 0xb0, buffer, vpd_len))
+                goto out;
 
         blk_queue_io_min(sdkp->disk->queue,
                          get_unaligned_be16(&buffer[6]) * sector_sz);
@@ -1984,6 +1984,7 @@ static void sd_read_block_limits(struct scsi_disk *sdkp)
                                 get_unaligned_be32(&buffer[32]) & ~(1 << 31);
         }
 
+ out:
         kfree(buffer);
 }
 
@@ -1993,20 +1994,23 @@ static void sd_read_block_limits(struct scsi_disk *sdkp)
  */
 static void sd_read_block_characteristics(struct scsi_disk *sdkp)
 {
-        char *buffer;
+        unsigned char *buffer;
         u16 rot;
+        const int vpd_len = 32;
 
-        /* Block Device Characteristics VPD */
-        buffer = scsi_get_vpd_page(sdkp->device, 0xb1);
+        buffer = kmalloc(vpd_len, GFP_KERNEL);
 
-        if (buffer == NULL)
-                return;
+        if (!buffer ||
+            /* Block Device Characteristics VPD */
+            scsi_get_vpd_page(sdkp->device, 0xb1, buffer, vpd_len))
+                goto out;
 
         rot = get_unaligned_be16(&buffer[4]);
 
         if (rot == 1)
                 queue_flag_set_unlocked(QUEUE_FLAG_NONROT, sdkp->disk->queue);
 
+ out:
         kfree(buffer);
 }