Re: [PATCH v3] scsi: ufs: WB is only available on LUN #0 to #7

2021-01-14 Thread Martin K. Petersen
On Mon, 11 Jan 2021 01:59:27 -0800, Jaegeuk Kim wrote:

> 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;
> 
> [...]

Applied to 5.12/scsi-queue, thanks!

[1/1] scsi: ufs: WB is only available on LUN #0 to #7
  https://git.kernel.org/mkp/scsi/c/a2fca52ee640

-- 
Martin K. Petersen  Oracle Linux Engineering


RE: [PATCH v3] scsi: ufs: WB is only available on LUN #0 to #7

2021-01-11 Thread Avri Altman
> 
> 
> From: Jaegeuk Kim 
> 
> 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
> }
> }
> 
> Signed-off-by: Jaegeuk Kim 
Reviewed-by: Avri Altman 


[PATCH v3] scsi: ufs: WB is only available on LUN #0 to #7

2021-01-11 Thread Jaegeuk Kim
From: Jaegeuk Kim 

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
}
}

Signed-off-by: Jaegeuk Kim 
---
 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 08e72b7eef6a..50e90416262b 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 14dfda735adf..580aa56965d0 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 2a715f13fe1d..48cbd4f294dd 100644
--- a/drivers/scsi/ufs/ufshcd.c
+++ b/drivers/scsi/ufs/ufshcd.c
@@ -3425,7 +3425,7 @@ 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,
-- 
2.30.0.284.gd98b1dd5eaa7-goog