CVEvulnerability
CVE-2026-97587
- Status
- Received
- Published
- 2026-09-25
- Last modified
- 2026-10-21
- Assigner
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Description
In the Linux kernel, the following vulnerability has been resolved:
perf: RISC-V: store available counter mask as bitmap
The available-counter mask was a single unsigned long, but iteration
uses RISCV_MAX_COUNTERS, which is 64. On RV32 that reads past the object.
Filling with an unsigned-long bit at index 32 and above is also wrong.
Use DECLARE_BITMAP and set_bit/bitmap helpers. Walk each bitmap word
into CFG_MATCH when checking events, when allocating an index, and when
stopping all counters. Set the counter base to i times BITS_PER_LONG.
Share the CFG_MATCH ecall through a small helper so the 32-bit argument
split is not duplicated. On qemu-system-riscv32 the probe bitmap has bits
above XLEN set, so the first word alone is not enough.
[[email protected]: updated to apply; fixed checkpatch.pl issues]
References
- https://git.kernel.org/stable/c/143668c424772979a45118dc9cc9c2c13a35f41d git.kernel.org
- https://git.kernel.org/stable/c/5a1b6379eed5b13eac0228b605b0bed988e547e9 git.kernel.org
- https://git.kernel.org/stable/c/6809da6e9c08ccc9a09cb0a48c61471679274aaa git.kernel.org
- https://git.kernel.org/stable/c/9bec7beaed074bcae4181fde9ff9dfbe4e7b0957 git.kernel.org
- https://git.kernel.org/stable/c/e5481db31f4654e9a1254d5d467d9b1ff2f8b1cb git.kernel.org