[PATCH 0/2] perf: Fix overflow in PERF_IDX2OFF() for Arm SPE and TRBE drivers

[Leo Yan]

If the AUX buffer size is specified as 2 GiB or larger, the expression
"(buf)->nr_pages << PAGE_SHIFT" may exceed 0x8000_0000. Since
(buf)->nr_pages is a signed integer, the shift can overflow and produce
a negative value. As a result, PERF_IDX2OFF() fails to work correctly.

Fix this by casting (buf)->nr_pages to unsigned long before the shift,
which allows PERF_IDX2OFF() to handle large buffers properly.

Signed-off-by: Leo Yan <leo.yan at arm.com>
---
Leo Yan (2):
      coresight: trbe: Prevent overflow in PERF_IDX2OFF()
      perf: arm_spe: Prevent overflow in PERF_IDX2OFF()

 drivers/hwtracing/coresight/coresight-trbe.c | 3 ++-
 drivers/perf/arm_spe_pmu.c                   | 3 ++-
 2 files changed, 4 insertions(+), 2 deletions(-)
---
base-commit: 5aca7966d2a7255ba92fd5e63268dd767b223aa5
change-id: 20250917-fix_aux_trace_index-9745674f5061

Best regards,
-- 
Leo Yan <leo.yan at arm.com>