CVE-2022-49220

Summary

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

dax: make sure inodes are flushed before destroy cache

A bug can be triggered by following command

$ modprobe nd_pmem && modprobe -r nd_pmem

[ 10.060014] BUG dax_cache (Not tainted): Objects remaining in dax_cache on __kmem_cache_shutdown() [ 10.060938] Slab 0x0000000085b729ac objects=9 used=1 fp=0x000000004f5ae469 flags=0x200000000010200(slab|head|node) [ 10.062433] Call Trace: [ 10.062673] dump_stack_lvl+0x34/0x44 [ 10.062865] slab_err+0x90/0xd0 [ 10.063619] __kmem_cache_shutdown+0x13b/0x2f0 [ 10.063848] kmem_cache_destroy+0x4a/0x110 [ 10.064058] __x64_sys_delete_module+0x265/0x300

This is caused by dax_fs_exit() not flushing inodes before destroy cache. To fix this issue, call rcu_barrier() before destroy cache.

Affected Software

VendorProductVersion RangeStatus
LinuxLinux7b6be8444e0f0dd675b54d059793423d3c9b4c03 < 770d42fff12d8595adda9025a0b92091f543e775affected
LinuxLinux7b6be8444e0f0dd675b54d059793423d3c9b4c03 < ec376f5c11c88c0215d173599db8449cd4196759affected
LinuxLinux7b6be8444e0f0dd675b54d059793423d3c9b4c03 < e2951eaa9398415ac054b7bd80b8163b6838ead4affected
LinuxLinux7b6be8444e0f0dd675b54d059793423d3c9b4c03 < f2a1e0eb70c2d954176c07d75d28742bde30e9f3affected
LinuxLinux7b6be8444e0f0dd675b54d059793423d3c9b4c03 < b786abe7c67c6ef71410c8e23292b3091d616ad1affected
LinuxLinux7b6be8444e0f0dd675b54d059793423d3c9b4c03 < a7e8de822e0b1979f08767c751f6c8a9c1d4ad86affected
LinuxLinux4.12affected
LinuxLinux0 < 4.12unaffected
LinuxLinux5.4.189 <= 5.4.*unaffected
LinuxLinux5.10.110 <= 5.10.*unaffected
LinuxLinux5.15.33 <= 5.15.*unaffected
LinuxLinux5.16.19 <= 5.16.*unaffected
LinuxLinux5.17.2 <= 5.17.*unaffected
LinuxLinux5.18 <= *unaffected

Weaknesses

References