In the Linux kernel, the following vulnerability has been resolved:
perf/x86/intel/pt: Fix crash with stop filters in single-range mode
Add a check for !buf->single before calling ptbufferregion_size in a place where a missing check can cause a kernel crash.
Fixes a bug introduced by commit 670638477aed ("perf/x86/intel/pt: Opportunistically use single range output mode"), which added a support for PT single-range output mode. Since that commit if a PT stop filter range is hit while tracing, the kernel will crash because of a null pointer dereference in pthandlestatus due to calling ptbufferregion_size without a ToPA configured.
The commit which introduced single-range mode guarded almost all uses of the ToPA buffer variables with checks of the buf->single variable, but missed the case where tracing was stopped by the PT hardware, which happens when execution hits a configured stop filter.
Tested that hitting a stop filter while PT recording successfully records a trace with this patch but crashes without this patch.
[
{
"id": "CVE-2022-48713-184dcf28",
"target": {
"function": "pt_handle_status",
"file": "arch/x86/events/intel/pt.c"
},
"signature_version": "v1",
"signature_type": "Function",
"source": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git@feffb6ae2c80b9a8206450cdef90f5943baced99",
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"deprecated": false
},
{
"id": "CVE-2022-48713-64301f7b",
"target": {
"file": "arch/x86/events/intel/pt.c"
},
"signature_version": "v1",
"signature_type": "Line",
"source": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git@feffb6ae2c80b9a8206450cdef90f5943baced99",
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"threshold": 0.9
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{
"id": "CVE-2022-48713-9135f30a",
"target": {
"function": "pt_handle_status",
"file": "arch/x86/events/intel/pt.c"
},
"signature_version": "v1",
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{
"id": "CVE-2022-48713-c48be9b5",
"target": {
"file": "arch/x86/events/intel/pt.c"
},
"signature_version": "v1",
"signature_type": "Line",
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