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 --- scripts/mod/mk_elfconfig.c | 32 ++++++++++++++++++++++++++++++++ 1 file changed, 32 insertions(+) create mode 100644 scripts/mod/mk_elfconfig.c (limited to 'scripts/mod/mk_elfconfig.c') diff --git a/scripts/mod/mk_elfconfig.c b/scripts/mod/mk_elfconfig.c new file mode 100644 index 000000000..e8cee4e4b --- /dev/null +++ b/scripts/mod/mk_elfconfig.c @@ -0,0 +1,32 @@ +// SPDX-License-Identifier: GPL-2.0 +#include +#include +#include +#include + +int +main(int argc, char **argv) +{ + unsigned char ei[EI_NIDENT]; + + if (fread(ei, 1, EI_NIDENT, stdin) != EI_NIDENT) { + fprintf(stderr, "Error: input truncated\n"); + return 1; + } + if (memcmp(ei, ELFMAG, SELFMAG) != 0) { + fprintf(stderr, "Error: not ELF\n"); + return 1; + } + switch (ei[EI_CLASS]) { + case ELFCLASS32: + printf("#define KERNEL_ELFCLASS ELFCLASS32\n"); + break; + case ELFCLASS64: + printf("#define KERNEL_ELFCLASS ELFCLASS64\n"); + break; + default: + exit(1); + } + + return 0; +} -- cgit v1.3.1