In the Linux kernel, the following vulnerability has been resolved:
net: stmmac: Fix accessing freed irq affinity_hint
In stmmac_request_irq_multi_msi(), a pointer to the stack variable cpu_mask is passed to irq_set_affinity_hint(). This value is stored in irq_desc->affinity_hint, but once stmmac_request_irq_multi_msi() returns, the pointer becomes dangling.
The affinity_hint is exposed via procfs with S_IRUGO permissions, allowing any unprivileged process to read it. Accessing this stale pointer can lead to:
All platforms that use stmmac with PCI MSI (Intel, Loongson, etc) are affected.
| Software | From | Fixed in |
|---|---|---|
| linux / linux_kernel | 5.13 | 6.12.36 |
| linux / linux_kernel | 6.13 | 6.13.12 |
| linux / linux_kernel | 6.14 | 6.14.3 |