[PATCH AUTOSEL 3.18 18/41] scsi: megaraid_sas: return error when create DMA pool failed

Sasha Levin
2019-03-27T18:26:01Z

From: Jason Yan <yanaijie@huawei.com>

[ Upstream commit bcf3b67d16a4c8ffae0aa79de5853435e683945c ]

when create DMA pool for cmd frames failed, we should return -ENOMEM,
instead of 0.
In some case in:

megasas_init_adapter_fusion()

-->megasas_alloc_cmds()
-->megasas_create_frame_pool
create DMA pool failed,
--> megasas_free_cmds() [1]

-->megasas_alloc_cmds_fusion()
failed, then goto fail_alloc_cmds.
-->megasas_free_cmds() [2]

we will call megasas_free_cmds twice, [1] will kfree cmd_list,
[2] will use cmd_list.it will cause a problem:

Unable to handle kernel NULL pointer dereference at virtual address
00000000
pgd = ffffffc000f70000
[00000000] *pgd=0000001fbf893003, *pud=0000001fbf893003,
*pmd=0000001fbf894003, *pte=006000006d000707
Internal error: Oops: 96000005 [#1] SMP
Modules linked in:
CPU: 18 PID: 1 Comm: swapper/0 Not tainted
task: ffffffdfb9290000 ti: ffffffdfb923c000 task.ti: ffffffdfb923c000
PC is at megasas_free_cmds+0x30/0x70
LR is at megasas_free_cmds+0x24/0x70
...
Call trace:
[<ffffffc0005b779c>] megasas_free_cmds+0x30/0x70
[<ffffffc0005bca74>] megasas_init_adapter_fusion+0x2f4/0x4d8
[<ffffffc0005b926c>] megasas_init_fw+0x2dc/0x760
[<ffffffc0005b9ab0>] megasas_probe_one+0x3c0/0xcd8
[<ffffffc0004a5abc>] local_pci_probe+0x4c/0xb4
[<ffffffc0004a5c40>] pci_device_probe+0x11c/0x14c
[<ffffffc00053a5e4>] driver_probe_device+0x1ec/0x430
[<ffffffc00053a92c>] __driver_attach+0xa8/0xb0
[<ffffffc000538178>] bus_for_each_dev+0x74/0xc8
[<ffffffc000539e88>] driver_attach+0x28/0x34
[<ffffffc000539a18>] bus_add_driver+0x16c/0x248
[<ffffffc00053b234>] driver_register+0x6c/0x138
[<ffffffc0004a5350>] __pci_register_driver+0x5c/0x6c
[<ffffffc000ce3868>] megasas_init+0xc0/0x1a8
[<ffffffc000082a58>] do_one_initcall+0xe8/0x1ec
[<ffffffc000ca7be8>] kernel_init_freeable+0x1c8/0x284
[<ffffffc0008d90b8>] kernel_init+0x1c/0xe4

Signed-off-by: Jason Yan <yanaijie@huawei.com>
Acked-by: Sumit Saxena <sumit.saxena@broadcom.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/scsi/megaraid/megaraid_sas_base.c | 1 +
1 file changed, 1 insertion(+)

diff --git a/drivers/scsi/megaraid/megaraid_sas_base.c b/drivers/scsi/megaraid/megaraid_sas_base.c
index 1ff0ece87644..24cc8786ff06 100644
--- a/drivers/scsi/megaraid/megaraid_sas_base.c
+++ b/drivers/scsi/megaraid/megaraid_sas_base.c
@@ -3743,6 +3743,7 @@ int megasas_alloc_cmds(struct megasas_instance *instance)
if (megasas_create_frame_pool(instance)) {
printk(KERN_DEBUG "megasas: Error creating frame DMA pool\n");
megasas_free_cmds(instance);
+ return -ENOMEM;
}

return 0;
--
2.19.1