Description (CNA)
In the Linux kernel, the following vulnerability has been resolved: parisc: Avoid crash due to unaligned access in unwinder Guenter Roeck reported this kernel crash on his emulated B160L machine: Starting network: udhcpc: started, v1.36.1 Backtrace: [<104320d4>] unwind_once+0x1c/0x5c [<10434a00>] walk_stackframe.isra.0+0x74/0xb8 [<10434a6c>] arch_stack_walk+0x28/0x38 [<104e5efc>] stack_trace_save+0x48/0x5c [<105d1bdc>] set_track_prepare+0x44/0x6c [<105d9c80>] ___slab_alloc+0xfc4/0x1024 [<105d9d38>] __slab_alloc.isra.0+0x58/0x90 [<105dc80c>] kmem_cache_alloc_noprof+0x2ac/0x4a0 [<105b8e54>] __anon_vma_prepare+0x60/0x280 [<105a823c>] __vmf_anon_prepare+0x68/0x94 [<105a8b34>] do_wp_page+0x8cc/0xf10 [<105aad88>] handle_mm_fault+0x6c0/0xf08 [<10425568>] do_page_fault+0x110/0x440 [<10427938>] handle_interruption+0x184/0x748 [<11178398>] schedule+0x4c/0x190 BUG: spinlock recursion on CPU#0, ifconfig/2420 lock: terminate_lock.2+0x0/0x1c, .magic: dead4ead, .owner: ifconfig/2420, .owner_cpu: 0 While creating the stack trace, the unwinder uses the stack pointer to guess the previous frame to read the previous stack pointer from memory. The crash happens, because the unwinder tries to read from unaligned memory and as such triggers the unalignment trap handler which then leads to the spinlock recursion and finally to a deadlock. Fix it by checking the alignment before accessing the memory.
Affected (CNA)
| Vendor / product | Versions |
|---|---|
| Linux / Linux | affected c8921d72e390cb6fca3fb2b0c2badfda851647eb before 9ac1f44723f26881b9fe7e69c7bc25397b879155; affected c8921d72e390cb6fca3fb2b0c2badfda851647eb before 009270208f76456c2cefcd565da263b90bb2eadb; affected c8921d72e390cb6fca3fb2b0c2badfda851647eb before fd9f30d1038ee1624baa17a6ff11effe5f7617cb |
| Linux / Linux | affected 4.19; unaffected 0 before 4.19; unaffected 6.12.58 through 6.12.*; unaffected 6.17.8 through 6.17.*; unaffected 6.18 through * |
CWE
No CWE identifiers supplied.