Vulnerability CVE-2023-52835
Published: 2024-05-21

Description:
In the Linux kernel, the following vulnerability has been resolved:

perf/core: Bail out early if the request AUX area is out of bound

When perf-record with a large AUX area, e.g 4GB, it fails with:

#perf record -C 0 -m ,4G -e arm_spe_0// -- sleep 1
failed to mmap with 12 (Cannot allocate memory)

and it reveals a WARNING with __alloc_pages():

------------[ cut here ]------------
WARNING: CPU: 44 PID: 17573 at mm/page_alloc.c:5568 __alloc_pages+0x1ec/0x248
Call trace:
__alloc_pages+0x1ec/0x248
__kmalloc_large_node+0xc0/0x1f8
__kmalloc_node+0x134/0x1e8
rb_alloc_aux+0xe0/0x298
perf_mmap+0x440/0x660
mmap_region+0x308/0x8a8
do_mmap+0x3c0/0x528
vm_mmap_pgoff+0xf4/0x1b8
ksys_mmap_pgoff+0x18c/0x218
__arm64_sys_mmap+0x38/0x58
invoke_syscall+0x50/0x128
el0_svc_common.constprop.0+0x58/0x188
do_el0_svc+0x34/0x50
el0_svc+0x34/0x108
el0t_64_sync_handler+0xb8/0xc0
el0t_64_sync+0x1a4/0x1a8

'rb->aux_pages' allocated by kcalloc() is a pointer array which is used to
maintains AUX trace pages. The allocated page for this array is physically
contiguous (and virtually contiguous) with an order of 0..MAX_ORDER. If the
size of pointer array crosses the limitation set by MAX_ORDER, it reveals a
WARNING.

So bail out early with -ENOMEM if the request AUX area is out of bound,
e.g.:

#perf record -C 0 -m ,4G -e arm_spe_0// -- sleep 1
failed to mmap with 12 (Cannot allocate memory)

 References:
https://git.kernel.org/stable/c/8c504f615d7ed60ae035c51d0c789137ced6797f
https://git.kernel.org/stable/c/788c0b3442ead737008934947730a6d1ff703734
https://git.kernel.org/stable/c/1a2a4202c60fcdffbf04f259002ce9bff39edece
https://git.kernel.org/stable/c/fd0df3f8719201dbe61a4d39083d5aecd705399a
https://git.kernel.org/stable/c/9ce4e87a8efd37c85766ec08b15e885cab08553a
https://git.kernel.org/stable/c/2424410f94a94d91230ced094062d859714c984a
https://git.kernel.org/stable/c/2e905e608e38cf7f8dcddcf8a6036e91a78444cb
https://git.kernel.org/stable/c/54aee5f15b83437f23b2b2469bcf21bdd9823916
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