CVE-2026-97934

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

tracing: Fix memory corruption from a "STACKTRACE" histogram key

"cpu", "CPU", "stacktrace" and "STACKTRACE" are generic fields, defined with an offset and a size of zero so that the filter code can match them by name. parse field() maps them onto their common * equivalents for backward compatibility, but unlike the common * names it hands the placeholder back to the caller instead of NULL.

create hist field() takes a non-NULL field as a promise that the record carries a stacktrace and picks HIST FIELD FN STACK, so the data loc word is read from offset 0, that is from common type, and its low 16 bits are followed as an offset into the record. What is found there becomes the length of an unbounded memcpy. Pick an event whose id is small enough that the offset stays inside its own record and the length is a kernel text address:

Oops: general protection fault, probably for non-canonical address RIP: 0010:rb next+0x23/0x60 RIP: 0010:memcpy+0xc/0x30 event hist trigger+0x2e7/0x12c0 Kernel panic - not syncing: Fatal exception in interrupt

Leave the field NULL, which is what the comment above the branch says the code does and what common stacktrace already does. FILTER CPU and FILTER COMM are left alone, their create hist field() branches never look at the field.