In the Linux kernel, the following vulnerability has been resolved:
drm/xe/reg_sr: Remove register pool
That pool implementation doesn't really work: if the krealloc happens to move the memory and return another address, the entries in the xarray become invalid, leading to use-after-free later:
BUG: KASAN: slab-use-after-free in xe_reg_sr_apply_mmio+0x570/0x760 [xe]
Read of size 4 at addr ffff8881244b2590 by task modprobe/2753
Allocated by task 2753:
kasan_save_stack+0x39/0x70
kasan_save_track+0x14/0x40
kasan_save_alloc_info+0x37/0x60
__kasan_kmalloc+0xc3/0xd0
__kmalloc_node_track_caller_noprof+0x200/0x6d0
krealloc_noprof+0x229/0x380
Simplify the code to fix the bug. A better pooling strategy may be added back later if needed.
(cherry picked from commit e5283bd4dfecbd3335f43b62a68e24dae23f59e4)
Exploitability
AV:LAC:LPR:LUI:NScope
S:UImpact
C:HI:HA:H7.8/CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H