From 555db56cc3e6fed3e7c8c789ffc4fac325ff98d5 Mon Sep 17 00:00:00 2001 From: Jaegeuk Kim Date: Sun, 10 Jan 2021 19:34:07 -0800 Subject: [PATCH] FROMLIST: scsi: ufs: WB is only available on LUN #0 to #7 Kernel stack violation when getting unit_descriptor/wb_buf_alloc_units from rpmb lun. The reason is the unit descriptor length is different per LU. The lengh of Normal LU is 45, while the one of rpmb LU is 35. int ufshcd_read_desc_param(struct ufs_hba *hba, ...) { param_offset=41; param_size=4; buff_len=45; ... buff_len=35 by rpmb LU; if (is_kmalloc) { /* Make sure we don't copy more data than available */ if (param_offset + param_size > buff_len) param_size = buff_len - param_offset; --> param_size = 250; memcpy(param_read_buf, &desc_buf[param_offset], param_size); --> memcpy(param_read_buf, desc_buf+41, 250); [ 141.868974][ T9174] Kernel panic - not syncing: stack-protector: Kernel stack is corrupted in: wb_buf_alloc_units_show+0x11c/0x11c } } Bug: 174701661 Link: https://lore.kernel.org/linux-scsi/20210111095927.1830311-1-jaegeuk@kernel.org/ Reviewed-by: Avri Altman Signed-off-by: Jaegeuk Kim Signed-off-by: Jaegeuk Kim Change-Id: I25205d465daa25b4bd330876ad05fcfd01195a56 --- drivers/scsi/ufs/ufs-sysfs.c | 3 ++- drivers/scsi/ufs/ufs.h | 6 ++++-- drivers/scsi/ufs/ufshcd.c | 2 +- 3 files changed, 7 insertions(+), 4 deletions(-) diff --git a/drivers/scsi/ufs/ufs-sysfs.c b/drivers/scsi/ufs/ufs-sysfs.c index ede7a4e6c187..662110100ec4 100644 --- a/drivers/scsi/ufs/ufs-sysfs.c +++ b/drivers/scsi/ufs/ufs-sysfs.c @@ -792,7 +792,8 @@ static ssize_t _pname##_show(struct device *dev, \ struct scsi_device *sdev = to_scsi_device(dev); \ struct ufs_hba *hba = shost_priv(sdev->host); \ u8 lun = ufshcd_scsi_to_upiu_lun(sdev->lun); \ - if (!ufs_is_valid_unit_desc_lun(&hba->dev_info, lun)) \ + if (!ufs_is_valid_unit_desc_lun(&hba->dev_info, lun, \ + _duname##_DESC_PARAM##_puname)) \ return -EINVAL; \ return ufs_sysfs_read_desc_param(hba, QUERY_DESC_IDN_##_duname, \ lun, _duname##_DESC_PARAM##_puname, buf, _size); \ diff --git a/drivers/scsi/ufs/ufs.h b/drivers/scsi/ufs/ufs.h index d593edb48767..d13a3108fba1 100644 --- a/drivers/scsi/ufs/ufs.h +++ b/drivers/scsi/ufs/ufs.h @@ -552,13 +552,15 @@ struct ufs_dev_info { * @return: true if the lun has a matching unit descriptor, false otherwise */ static inline bool ufs_is_valid_unit_desc_lun(struct ufs_dev_info *dev_info, - u8 lun) + u8 lun, u8 param_offset) { if (!dev_info || !dev_info->max_lu_supported) { pr_err("Max General LU supported by UFS isn't initialized\n"); return false; } - + /* WB is available only for the logical unit from 0 to 7 */ + if (param_offset == UNIT_DESC_PARAM_WB_BUF_ALLOC_UNITS) + return lun < UFS_UPIU_MAX_WB_LUN_ID; return lun == UFS_UPIU_RPMB_WLUN || (lun < dev_info->max_lu_supported); } diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c index da905a76e857..5063320aace8 100644 --- a/drivers/scsi/ufs/ufshcd.c +++ b/drivers/scsi/ufs/ufshcd.c @@ -3421,7 +3421,7 @@ static inline int ufshcd_read_unit_desc_param(struct ufs_hba *hba, * Unit descriptors are only available for general purpose LUs (LUN id * from 0 to 7) and RPMB Well known LU. */ - if (!ufs_is_valid_unit_desc_lun(&hba->dev_info, lun)) + if (!ufs_is_valid_unit_desc_lun(&hba->dev_info, lun, param_offset)) return -EOPNOTSUPP; return ufshcd_read_desc_param(hba, QUERY_DESC_IDN_UNIT, lun,