[lvc-project] [PATCH] scsi: elx: efct: adjust error handling inside efct_hw_setup_io

[Fedor Pchelkin]

IO and WQE buffers are allocated once per HW and can be reused later. If
WQE buffers allocation fails then the whole allocation is marked as failed
but already created IO array internal objects are not freed. hw->io is
freed but not nullified in that specific case - it may become a problem
later as efct_hw_setup_io() is supposed to be reusable for the same HW.

While at it, use kcalloc instead of kmalloc_array/memset-zero combination
and get rid of some needless NULL assignments: nullifying hw->io[i]
elements just before freeing hw->io is not really useful.

Found by Linux Verification Center (linuxtesting.org).

Fixes: 4df84e846624 ("scsi: elx: efct: Driver initialization routines")
Cc: stable at vger.kernel.org
Signed-off-by: Fedor Pchelkin <pchelkin at ispras.ru>
---
 drivers/scsi/elx/efct/efct_hw.c | 14 ++++----------
 1 file changed, 4 insertions(+), 10 deletions(-)

diff --git a/drivers/scsi/elx/efct/efct_hw.c b/drivers/scsi/elx/efct/efct_hw.c
index 5a5525054d71..e5486e6949f9 100644
--- a/drivers/scsi/elx/efct/efct_hw.c
+++ b/drivers/scsi/elx/efct/efct_hw.c
@@ -487,12 +487,10 @@ efct_hw_setup_io(struct efct_hw *hw)
 	struct efct *efct = hw->os;
 
 	if (!hw->io) {
-		hw->io = kmalloc_array(hw->config.n_io, sizeof(io), GFP_KERNEL);
+		hw->io = kcalloc(hw->config.n_io, sizeof(io), GFP_KERNEL);
 		if (!hw->io)
 			return -ENOMEM;
 
-		memset(hw->io, 0, hw->config.n_io * sizeof(io));
-
 		for (i = 0; i < hw->config.n_io; i++) {
 			hw->io[i] = kzalloc(sizeof(*io), GFP_KERNEL);
 			if (!hw->io[i])
@@ -502,10 +500,8 @@ efct_hw_setup_io(struct efct_hw *hw)
 		/* Create WQE buffs for IO */
 		hw->wqe_buffs = kzalloc((hw->config.n_io * hw->sli.wqe_size),
 					GFP_KERNEL);
-		if (!hw->wqe_buffs) {
-			kfree(hw->io);
-			return -ENOMEM;
-		}
+		if (!hw->wqe_buffs)
+			goto error;
 
 	} else {
 		/* re-use existing IOs, including SGLs */
@@ -586,10 +582,8 @@ efct_hw_setup_io(struct efct_hw *hw)
 
 	return 0;
 error:
-	for (i = 0; i < hw->config.n_io && hw->io[i]; i++) {
+	for (i = 0; i < hw->config.n_io && hw->io[i]; i++)
 		kfree(hw->io[i]);
-		hw->io[i] = NULL;
-	}
 
 	kfree(hw->io);
 	hw->io = NULL;
-- 
2.39.2