This patch series addresses a number of robustness, security, and
correctness issues in the ENETC driver's SR-IOV subsystem, focusing
primarily on the VF-to-PF mailbox communication path.
The series can be grouped into the following categories:
1. DoS and security fixes:
- Prevent an unbounded loop DoS in the VF-to-PF message handler,
which could be triggered by a malicious or misbehaving VF.
- Fix a TOCTOU (Time-of-Check-Time-of-Use) race and add proper
validation of VF MAC addresses to prevent spoofing or invalid
configuration from being applied.
2. Race condition fixes:
- Fix a race condition in VF MAC address configuration that could
lead to inconsistent state between the VF request and PF
application.
- Fix a race condition during SR-IOV teardown that could cause
VF->PF mailbox operations to time out, resulting in unnecessary
errors during shutdown.
3. Memory safety fixes:
- Fix a DMA write to freed memory in enetc_msg_free_mbx(), which
could cause silent memory corruption or system instability.
4. Error handling and initialization fixes:
- Fix missing error code propagation when pf->vf_state allocation
fails, ensuring callers receive a proper errno instead of
succeeding silently.
- Fix incorrect mailbox message status values returned to VFs,
which could cause VFs to misinterpret PF responses.
- Fix initialization order to prevent the use of uninitialized
resources during driver probe, which could cause undefined
behavior on certain configurations.
5. Diagnostics improvement:
- Add rate limiting to VF mailbox error messages to prevent log
flooding in the presence of a misbehaving VF.
These fixes improve the overall stability and security of the ENETC
SR-IOV implementation, particularly in multi-tenant environments where
VFs may be assigned to untrusted guests.
---
v3:
1. Improve the implementation of patch 7, such as add new macros
ENETC_PSIMR_MASK and ENETC_PSIMR_BIT, ENETC_PSIIER is enabled based
on the number of active VSIs, mr_status is derived from ENETC_PSIIDR
and ENETC_PSIMSGRR and so on. Also update the subject and commit
message.
2. Update the commit message of patch 8, add description of the change
in enetc_msg_psi_free().
3. Collect the Reviewed-by tags.
v2 link: https://lore.kernel.org/imx/20260518030535.1057228-1-wei.fang@nxp.com/
v2:
1. Copy the message content from DMA memory to local memory
2. Patch 3 and 5 in v1 are merged into patch 8 in v2
3. Add more fix patches, such as patch 1, 2, 6 and 7
v1 link: https://lore.kernel.org/imx/20260513103021.2190593-1-wei.fang@nxp.com/
---
Wei Fang (9):
net: enetc: fix incorrect mailbox message status returned to VFs
net: enetc: fix missing error code when pf->vf_state allocation fails
net: enetc: add ratelimiting to VF mailbox error messages
net: enetc: fix TOCTOU race and validate VF MAC address
net: enetc: fix race condition in VF MAC address configuration
net: enetc: fix DMA write to freed memory in enetc_msg_free_mbx()
net: enetc: fix unbounded loop and interrupt handling in VF-to-PF
messaging
net: enetc: fix init and teardown order to prevent use of unsafe
resources
net: enetc: avoid VF->PF mailbox timeout during SR-IOV teardown
.../net/ethernet/freescale/enetc/enetc_hw.h | 15 ++-
.../net/ethernet/freescale/enetc/enetc_msg.c | 106 ++++++++++--------
.../net/ethernet/freescale/enetc/enetc_pf.c | 75 +++++++++----
.../net/ethernet/freescale/enetc/enetc_pf.h | 1 +
4 files changed, 127 insertions(+), 70 deletions(-)
--
2.34.1