CVE-2023-53484

In the Linux kernel, the following vulnerability has been resolved: lib: cpu_rmap: Avoid use after free on rmap->obj array entries When calling irq_set_affinity_notifier() with NULL at the notify argument, it will cause freeing of the glue pointer in the corresponding array entry but will leave the pointer in the array. A subsequent call to free_irq_cpu_rmap() will try to free this entry again leading to possible use after free. Fix that by setting NULL to the array entry and checking that we have non-zero at the array entry when iterating over the array in free_irq_cpu_rmap(). The current code does not suffer from this since there are no cases where irq_set_affinity_notifier(irq, NULL) (note the NULL passed for the notify arg) is called, followed by a call to free_irq_cpu_rmap() so we don't hit and issue. Subsequent patches in this series excersize this flow, hence the required fix.

• linux linux kernel (>= 3.8.1 < 4.14.316) • linux linux kernel (>= 4.15 < 4.19.284) • linux linux kernel (>= 4.20 < 5.4.244) • linux linux kernel (>= 5.5 < 5.10.181) • linux linux kernel (>= 5.11 < 5.15.113) • linux linux kernel (>= 5.16 < 6.1.30) • linux linux kernel (>= 6.2 < 6.3.4) • linux linux kernel 3.8