From 836b2fe544a5e9b5ce116622cb36fba33838c6fd Mon Sep 17 00:00:00 2001 From: Eduard Zingerman Date: Fri, 4 Sep 2026 01:33:23 -0700 Subject: selftests/bpf: Check that JMP32 pointer vs zero jumps are not predicted Add jmp32_ptr_vs_zero_jne: the fall-through of the 32-bit compare, which the verifier used to skip, contains an out of bounds map value access, hence w/o the previous patch the program is accepted. See previous patch for detailed description. Reported-by: Nicholas Carlini Suggested-by: Nicholas Carlini Signed-off-by: Eduard Zingerman Link: https://lore.kernel.org/bpf/20260904083325.2083493-6-eddyz87@gmail.com Signed-off-by: Kumar Kartikeya Dwivedi --- tools/perf/util/cacheline.c | 25 +++++++++++++++++++++++++ 1 file changed, 25 insertions(+) create mode 100644 tools/perf/util/cacheline.c (limited to 'tools/perf/util/cacheline.c') diff --git a/tools/perf/util/cacheline.c b/tools/perf/util/cacheline.c new file mode 100644 index 000000000..e98b5250a --- /dev/null +++ b/tools/perf/util/cacheline.c @@ -0,0 +1,25 @@ +// SPDX-License-Identifier: GPL-2.0 +#include "cacheline.h" +#include + +#ifdef _SC_LEVEL1_DCACHE_LINESIZE +#define cache_line_size(cacheline_sizep) *cacheline_sizep = sysconf(_SC_LEVEL1_DCACHE_LINESIZE) +#else +#include +#include "debug.h" +static void cache_line_size(int *cacheline_sizep) +{ + if (sysfs__read_int("devices/system/cpu/cpu0/cache/index0/coherency_line_size", cacheline_sizep)) + pr_debug("cannot determine cache line size"); +} +#endif + +int cacheline_size(void) +{ + static int size; + + if (!size) + cache_line_size(&size); + + return size; +} -- cgit v1.3.1