| From 934a51fb4701229a1ad7aa0b89f43fec38206b62 Mon Sep 17 00:00:00 2001 |
| From: Adrian Hunter <adrian.hunter@intel.com> |
| Date: Wed, 14 Aug 2019 15:59:50 +0300 |
| Subject: scsi: ufs: Fix NULL pointer dereference in ufshcd_config_vreg_hpm() |
| |
| [ Upstream commit 7c7cfdcf7f1777c7376fc9a239980de04b6b5ea1 ] |
| |
| Fix the following BUG: |
| |
| [ 187.065689] BUG: kernel NULL pointer dereference, address: 000000000000001c |
| [ 187.065790] RIP: 0010:ufshcd_vreg_set_hpm+0x3c/0x110 [ufshcd_core] |
| [ 187.065938] Call Trace: |
| [ 187.065959] ufshcd_resume+0x72/0x290 [ufshcd_core] |
| [ 187.065980] ufshcd_system_resume+0x54/0x140 [ufshcd_core] |
| [ 187.065993] ? pci_pm_restore+0xb0/0xb0 |
| [ 187.066005] ufshcd_pci_resume+0x15/0x20 [ufshcd_pci] |
| [ 187.066017] pci_pm_thaw+0x4c/0x90 |
| [ 187.066030] dpm_run_callback+0x5b/0x150 |
| [ 187.066043] device_resume+0x11b/0x220 |
| |
| Voltage regulators are optional, so functions must check they exist |
| before dereferencing. |
| |
| Note this issue is hidden if CONFIG_REGULATORS is not set, because the |
| offending code is optimised away. |
| |
| Notes for stable: |
| |
| The issue first appears in commit 57d104c153d3 ("ufs: add UFS power |
| management support") but is inadvertently fixed in commit 60f0187031c0 |
| ("scsi: ufs: disable vccq if it's not needed by UFS device") which in |
| turn was reverted by commit 730679817d83 ("Revert "scsi: ufs: disable vccq |
| if it's not needed by UFS device""). So fix applies v3.18 to v4.5 and |
| v5.1+ |
| |
| Fixes: 57d104c153d3 ("ufs: add UFS power management support") |
| Fixes: 730679817d83 ("Revert "scsi: ufs: disable vccq if it's not needed by UFS device"") |
| Cc: stable@vger.kernel.org |
| Signed-off-by: Adrian Hunter <adrian.hunter@intel.com> |
| Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> |
| Signed-off-by: Sasha Levin <sashal@kernel.org> |
| --- |
| drivers/scsi/ufs/ufshcd.c | 3 +++ |
| 1 file changed, 3 insertions(+) |
| |
| diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c |
| index b140e81c4f7da..fd8bbd2b5d0eb 100644 |
| --- a/drivers/scsi/ufs/ufshcd.c |
| +++ b/drivers/scsi/ufs/ufshcd.c |
| @@ -4418,6 +4418,9 @@ static inline int ufshcd_config_vreg_lpm(struct ufs_hba *hba, |
| static inline int ufshcd_config_vreg_hpm(struct ufs_hba *hba, |
| struct ufs_vreg *vreg) |
| { |
| + if (!vreg) |
| + return 0; |
| + |
| return ufshcd_config_vreg_load(hba->dev, vreg, vreg->max_uA); |
| } |
| |
| -- |
| 2.20.1 |
| |