CVE-2024-53121: net/mlx5: fs, lock FTE when checking if active
Description
In the Linux kernel, the following vulnerability has been resolved:
net/mlx5: fs, lock FTE when checking if active
The referenced commits introduced a two-step process for deleting FTEs:
- Lock the FTE, delete it from hardware, set the hardware deletion function
to NULL and unlock the FTE.
- Lock the parent flow group, delete the software copy of the FTE, and
remove it from the xarray.
However, this approach encounters a race condition if a rule with the same
match value is added simultaneously. In this scenario, fs_core may set the
hardware deletion function to NULL prematurely, causing a panic during
subsequent rule deletions.
To prevent this, ensure the active flag of the FTE is checked under a lock,
which will prevent the fs_core layer from attaching a new steering rule to
an FTE that is in the process of deletion.
[ 438.967589] MOSHE: 2496 mlx5_del_flow_rules del_hw_func
[ 438.968205] ------------[ cut here ]------------
[ 438.968654] refcount_t: decrement hit 0; leaking memory.
[ 438.969249] WARNING: CPU: 0 PID: 8957 at lib/refcount.c:31 refcount_warn_saturate+0xfb/0x110
[ 438.970054] Modules linked in: act_mirred cls_flower act_gact sch_ingress openvswitch nsh mlx5_vdpa vringh vhost_iotlb vdpa mlx5_ib mlx5_core xt_conntrack xt_MASQUERADE nf_conntrack_netlink nfnetlink xt_addrtype iptable_nat nf_nat br_netfilter rpcsec_gss_krb5 auth_rpcgss oid_registry overlay rpcrdma rdma_ucm ib_iser libiscsi scsi_transport_iscsi ib_umad rdma_cm ib_ipoib iw_cm ib_cm i...
Classification
CVE ID: CVE-2024-53121
CVSS Base Severity: LOW
CVSS Base Score: 0.0
Affected Products
Vendor: Linux
Product: Linux
Exploit Prediction Scoring System (EPSS)
EPSS Score: 0.04% (probability of being exploited)
EPSS Percentile: 5.06% (scored less or equal to compared to others)
EPSS Date: 2025-02-03 (when was this score calculated)
References
https://git.kernel.org/stable/c/bfba288f53192db08c68d4c568db9783fb9cb838https://git.kernel.org/stable/c/094d1a2121cee1e85ab07d74388f94809dcfb5b9
https://git.kernel.org/stable/c/933ef0d17f012b653e9e6006e3f50c8d0238b5ed
https://git.kernel.org/stable/c/9ca314419930f9135727e39d77e66262d5f7bef6