This is a note to let you know that I've just added the patch titled scsi: ufs: core: Fix NULL pointer dereference to the 5.15-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: scsi-ufs-core-fix-null-pointer-dereference.patch and it can be found in the queue-5.15 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit 7d0b01ac4a9d0ccd0b75878bfc98719db64dfd82 Author: Bean Huo <beanhuo@xxxxxxxxxx> Date: Wed Sep 29 22:06:38 2021 +0200 scsi: ufs: core: Fix NULL pointer dereference [ Upstream commit 1da3b0141e74c18c2377d4c2655406a90a87742f ] Calling ufshcd_rpm_{get/put}_sync() prior to ufshcd_scsi_add_wlus() being called will trigger a NULL pointer dereference. This is because hba->sdev_ufs_device is initialized in ufshcd_scsi_add_wlus(). Unable to handle kernel NULL pointer dereference at virtual address 0000000000000348 Mem abort info: ESR = 0x96000004 EC = 0x25: DABT (current EL), IL = 32 bits SET = 0, FnV = 0 EA = 0, S1PTW = 0 FSC = 0x04: level 0 translation fault Data abort info: ISV = 0, ISS = 0x00000004 CM = 0, WnR = 0 [0000000000000348] user address but active_mm is swapper Internal error: Oops: 96000004 [#1] PREEMPT SMP Modules linked in: CPU: 0 PID: 91 Comm: kworker/u16:1 Not tainted 5.15.0-rc1-beanhuo-linaro-1423 Hardware name: MicronRB (DT) Workqueue: events_unbound async_run_entry_fn pstate: 20000005 (nzCv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=--) pc : pm_runtime_drop_link+0x128/0x338 lr : ufshpb_get_dev_info+0x8c/0x148 sp : ffff800012573c10 x29: ffff800012573c10 x28: 0000000000000000 x27: 0000000000000003 x26: ffff000001d21298 x25: 000000005abcea60 x24: ffff800011d89000 x23: 0000000000000001 x22: ffff000001d21880 x21: ffff000001ec9300 x20: 0000000000000004 x19: 0000000000000198 x18: ffffffffffffffff x17: 0000000000000000 x16: 0000000000000000 x15: 0000000000041400 x14: 5eee00201100200a x13: 000000000000bb03 x12: 0000000000000000 x11: 0000000000000100 x10: 0200000000000000 x9 : bb0000021a162c01 x8 : 0302010021021003 x7 : 0000000000000000 x6 : ffff800012573af0 x5 : 0000000000000001 x4 : 0000000000000001 x3 : 0000000000000200 x2 : 0000000000000348 x1 : 0000000000000348 x0 : ffff80001095308c Call trace: pm_runtime_drop_link+0x128/0x338 ufshpb_get_dev_info+0x8c/0x148 ufshcd_probe_hba+0xda0/0x11b8 ufshcd_async_scan+0x34/0x330 async_run_entry_fn+0x38/0x180 process_one_work+0x1f4/0x498 worker_thread+0x48/0x480 kthread+0x140/0x158 ret_from_fork+0x10/0x20 Code: 88027c01 35ffffa2 17fff6c4 f9800051 (885f7c40) ---[ end trace 2ba541335f595c95 ] ufshpb_get_dev_info() is only called during asynchronous scanning and at that time pm_runtime_get_sync() has been called: ... /* Hold auto suspend until async scan completes */ pm_runtime_get_sync(dev); atomic_set(&hba->scsi_block_reqs_cnt, 0); ... ufshcd_async_scan() ufshcd_probe_hba(hba, true); ufshcd_device_params_init(hba); ufshpb_get_dev_info(); ... pm_runtime_put_sync(hba->dev); Remove ufshcd_rpm_{get/put}_sync() from ufshpb_get_dev_info() to fix this problem. Link: https://lore.kernel.org/r/20210929200640.828611-2-huobean@xxxxxxxxx Fixes: 351b3a849ac7 ("scsi: ufs: ufshpb: Use proper power management API") Signed-off-by: Bean Huo <beanhuo@xxxxxxxxxx> Signed-off-by: Martin K. Petersen <martin.petersen@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/drivers/scsi/ufs/ufshpb.c b/drivers/scsi/ufs/ufshpb.c index 46cdfb0dfca94..3b1a90b1d82ac 100644 --- a/drivers/scsi/ufs/ufshpb.c +++ b/drivers/scsi/ufs/ufshpb.c @@ -2598,11 +2598,8 @@ void ufshpb_get_dev_info(struct ufs_hba *hba, u8 *desc_buf) if (version == HPB_SUPPORT_LEGACY_VERSION) hpb_dev_info->is_legacy = true; - ufshcd_rpm_get_sync(hba); ret = ufshcd_query_attr_retry(hba, UPIU_QUERY_OPCODE_READ_ATTR, QUERY_ATTR_IDN_MAX_HPB_SINGLE_CMD, 0, 0, &max_hpb_single_cmd); - ufshcd_rpm_put_sync(hba); - if (ret) dev_err(hba->dev, "%s: idn: read max size of single hpb cmd query request failed", __func__);