[SRU][F:linux-bluefield][PATCH v4 0/4] Updates to mlx-bootctl

Shravan Kumar Ramani shravankr at nvidia.com
Fri Jun 25 12:03:43 UTC 2021


v3 --> v4
Redo split as follows:
1. Fix exclusion issues around arm_smccc_smc
2. Fix potential buffer overflow
3. Support VPD info in EEPROM MFG
4. Update license and version info

v2 --> v3
Add mutex lock/unlock for SMC calls in show functions, similar to store.
Use PAGE_SIZE macro as buffer size for snprintf calls in DRIVER_ATTR_RW functions.
Use snprintf instead of sprintf in post_reset_wdog_show.
In secure_boot_fuse_state_show, the string comes from the function itself unlike the rest. So it is protected against buffer overflow.

v1 --> v2
Split single patch into 3 separate patches based on functionality as suggested.

1. Fix exclusion issues around arm_smccc_smc
BugLink: https://bugs.launchpad.net/bugs/1933642
SRU Justification:

[Impact]
Exclusion is being handled around arm_smccc_smc() only in the store functions. It should be implemented in the show functions also as this call might not be thread-safe.

[Fix]
Add mutex_lock/unlock around arm_smccc_smc calls in the show functions.

[Test Case]
Multiple simultaneous accesses to a sysfs entry exposed by the driver are successful.

[Regression Potential]
Can be considered minimum

2. Fix potential buffer overflow
BugLink: https://bugs.launchpad.net/bugs/1931981
SRU Justification:

[Impact]
The sysfs store/show functions use sprintf without specifying a size which could lead to potential buffer overflow.

[Fix]
Replace sprintf with snprintf to avoid buffer overflow. Also, remove the redundant strlen usage since count is already available in the _store functions.

[Test Plan]
Read/write access to the EEPROM MFG fields can be tested via the sysfs entries that are exposed by the driver. Please note that the MFG partition is locked in order to protect the data and this could block all writes to it. In order to enable writes to the EEPROM, the MFG Info needs to be reset via the UEFI Device Manager.

[Regression Potential]
Can be considered minimum.

3. Support VPD info in EEPROM MFG
BugLink: https://bugs.launchpad.net/bugs/1931843
SRU Justification:

[Impact]
The EEPROM MFG partition on BlueField-2 has been updated to include the VPD information for each card. In order to access these newly added fields, the mlx-bootctl driver needs to be updated to provide an access mechanism.

[Fix]
Add support for VPD fields in the EEPROM MFG and provide access to these via sysfs entries. The newly added sysfs entries are: sku (SKU ID), modl (Model Number), sn (Serial Number) and uuid (UUID). And the previously added opn_str sysfs has been renamed to opn.

[Test Case]
Though the driver provides read and write access through sysfs, the contents of the MFG partition are written during Manufacturing and then locked in order to protect the info. Writing to this partition will therefore require resetting the MFG info from the UEFI Device Manager, which will unlock the partition and allow for it to be reprogrammed.
Reading the sysfs entries will print the contents of each field. It could also be empty if the field was not programmed earlier.

[Regression Potential]
Can be considered minimum, since the new fields have been added without interfering with the existing fields which might already be present in the EEPROM.

4. Update license and version info
BugLink: https://bugs.launchpad.net/bugs/1931984
SRU Justification:

[Impact]
License info needs to be updated since the current info is no longer accurate.
Driver version needs to be incremented since new features have been added.

[Fix]
Update license info to "Dual BSD/GPL".
Increment version to 1.4

[Test Plan]
Verify version change

[Regression Potential]
None

Shravan Kumar Ramani (4):
  UBUNTU: SAUCE: mlx-bootctl: Fix exclusion issues around arm_smccc_smc
  UBUNTU: SAUCE: mlx-bootctl: Fix potential buffer overflow
  UBUNTU: SAUCE: mlx-bootctl: Support VPD info in EEPROM MFG
  UBUNTU: SAUCE: mlx-bootctl: Update license and version info

 drivers/platform/mellanox/mlx-bootctl.c | 373 ++++++++++++++++++------
 1 file changed, 290 insertions(+), 83 deletions(-)

-- 
2.30.1




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