queue-4.4/scsi-qla4xxx-avoid-freeing-unallocated-dma-memory.patch

   1 From 8256f43fcb13e186302a89124f75ed439fa263ba Mon Sep 17 00:00:00 2001
   2 From: Arnd Bergmann <arnd@arndb.de>
   3 Date: Fri, 22 Mar 2019 15:25:03 +0100
   4 Subject: scsi: qla4xxx: avoid freeing unallocated dma memory
   5
   6 [ Upstream commit 608f729c31d4caf52216ea00d20092a80959256d ]
   7
   8 Clang -Wuninitialized notices that on is_qla40XX we never allocate any DMA
   9 memory in get_fw_boot_info() but attempt to free it anyway:
  10
  11 drivers/scsi/qla4xxx/ql4_os.c:5915:7: error: variable 'buf_dma' is used uninitialized whenever 'if' condition is false
  12       [-Werror,-Wsometimes-uninitialized]
  13                 if (!(val & 0x07)) {
  14                     ^~~~~~~~~~~~~
  15 drivers/scsi/qla4xxx/ql4_os.c:5985:47: note: uninitialized use occurs here
  16         dma_free_coherent(&ha->pdev->dev, size, buf, buf_dma);
  17                                                      ^~~~~~~
  18 drivers/scsi/qla4xxx/ql4_os.c:5915:3: note: remove the 'if' if its condition is always true
  19                 if (!(val & 0x07)) {
  20                 ^~~~~~~~~~~~~~~~~~~
  21 drivers/scsi/qla4xxx/ql4_os.c:5885:20: note: initialize the variable 'buf_dma' to silence this warning
  22         dma_addr_t buf_dma;
  23                           ^
  24                            = 0
  25
  26 Skip the call to dma_free_coherent() here.
  27
  28 Fixes: 2a991c215978 ("[SCSI] qla4xxx: Boot from SAN support for open-iscsi")
  29 Signed-off-by: Arnd Bergmann <arnd@arndb.de>
  30 Reviewed-by: Nathan Chancellor <natechancellor@gmail.com>
  31 Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
  32 Signed-off-by: Sasha Levin <sashal@kernel.org>
  33 ---
  34  drivers/scsi/qla4xxx/ql4_os.c | 2 +-
  35  1 file changed, 1 insertion(+), 1 deletion(-)
  36
  37 diff --git a/drivers/scsi/qla4xxx/ql4_os.c b/drivers/scsi/qla4xxx/ql4_os.c
  38 index c158967b59d7b..d220b4f691c77 100644
  39 --- a/drivers/scsi/qla4xxx/ql4_os.c
  40 +++ b/drivers/scsi/qla4xxx/ql4_os.c
  41 @@ -5939,7 +5939,7 @@ static int get_fw_boot_info(struct scsi_qla_host *ha, uint16_t ddb_index[])
  42                 val = rd_nvram_byte(ha, sec_addr);
  43                 if (val & BIT_7)
  44                         ddb_index[1] = (val & 0x7f);
  45 -
  46 +               goto exit_boot_info;
  47         } else if (is_qla80XX(ha)) {
  48                 buf = dma_alloc_coherent(&ha->pdev->dev, size,
  49                                          &buf_dma, GFP_KERNEL);
  50 --
  51 2.20.1
  52