From b51f7842486d3b2b19eea65431b1f3c21c1c7ae1 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 5e4d0a46416c..97dcd9c3befa 100644 --- a/drivers/scsi/ufs/ufs-sysfs.c +++ b/drivers/scsi/ufs/ufs-sysfs.c @@ -785,7 +785,8 @@ 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 f8ab16f30fdc..07ca39008b84 100644 --- a/drivers/scsi/ufs/ufs.h +++ b/drivers/scsi/ufs/ufs.h @@ -551,13 +551,15 @@ 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 991ae3e52aa1..d67067733629 100644 --- a/drivers/scsi/ufs/ufshcd.c +++ b/drivers/scsi/ufs/ufshcd.c @@ -3418,7 +3418,7 @@ 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,