Overview
About vulnerability
In the Linux kernel, the following vulnerability has been resolved:
dpaa2-switch: prevent ZERO_SIZE_PTR dereference when num_ifs is zero
The driver allocates arrays for ports, FDBs, and filter blocks using kcalloc() with ethsw->sw_attr.num_ifs as the element count. When the device reports zero interfaces (either due to hardware configuration or firmware issues), kcalloc(0, …) returns ZERO_SIZE_PTR (0x10) instead of NULL.
Later in dpaa2_switch_probe(), the NAPI initialization unconditionally accesses ethsw->ports[0]->netdev, which attempts to dereference ZERO_SIZE_PTR (address 0x10), resulting in a kernel panic.
Add a check to ensure num_ifs is greater than zero after retrieving device attributes. This prevents the zero-sized allocations and subsequent invalid pointer dereference.
Details
- Affected product:
- AlmaLinux 9.2 ESU , TuxCare 9.6 ESU
- Affected packages:
- kernel @ 5.14.0 (+1 more)
In the Linux kernel, the following vulnerability has been resolved:
dpaa2-switch: prevent ZERO_SIZE_PTR dereference when num_ifs is zero
The driver allocates arrays for ports, FDBs, and filter blocks using kcalloc() with ethsw->sw_attr.num_ifs as the element count. When the device reports zero interfaces (either due to hardware configuration or firmware issues), kcalloc(0, …) returns ZERO_SIZE_PTR (0x10) instead of NULL.
Later in dpaa2_switch_probe(), the NAPI initialization unconditionally accesses ethsw->ports[0]->netdev, which attempts to dereference ZERO_SIZE_PTR (address 0x10), resulting in a kernel panic.
Add a check to ensure num_ifs is greater than zero after retrieving device attributes. This prevents the zero-sized allocations and subsequent invalid pointer dereference.