In the Linux kernel, the following vulnerability has been resolved:arm64: errata: Add missing sentinels to Spectre-BHB MIDR arraysCommit a5951389e58d ("arm64: errata: Add newer ARM cores to the
spectre_bhb_loop_affected() lists") added some additional CPUs to the
Spectre-BHB workaround, including some new arrays for designs that
require new 'k' values for the workaround to be effective.Unfortunately, the new arrays omitted the sentinel entry and so
is_midr_in_range_list() will walk off the end when it doesn't find a
match. With UBSAN enabled, this leads to a crash during boot when
is_midr_in_range_list() is inlined (which was more common prior to
c8c2647e69be ("arm64: Make  _midr_in_range_list() an exported
function")):|  Internal error: aarch64 BRK: 00000000f2000001 [#1] PREEMPT SMP
 |  pstate: 804000c5 (Nzcv daIF +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
 |  pc : spectre_bhb_loop_affected+0x28/0x30
 |  lr : is_spectre_bhb_affected+0x170/0x190
 | [...]
 |  Call trace:
 |   spectre_bhb_loop_affected+0x28/0x30
 |   update_cpu_capabilities+0xc0/0x184
 |   init_cpu_features+0x188/0x1a4
 |   cpuinfo_store_boot_cpu+0x4c/0x60
 |   smp_prepare_boot_cpu+0x38/0x54
 |   start_kernel+0x8c/0x478
 |   __primary_switched+0xc8/0xd4
 |  Code: 6b09011f 54000061 52801080 d65f03c0 (d4200020)
 |  ---[ end trace 0000000000000000 ]---
 |  Kernel panic - not syncing: aarch64 BRK: Fatal exceptionAdd the missing sentinel entries.