From 506ada89629ec7059b96ecfb0dc7d33ece0103ca Mon Sep 17 00:00:00 2001 From: Eduard Zingerman Date: Fri, 4 Sep 2026 17:05:56 -0700 Subject: bpf: mark a NULL kfunc argument precise check_kfunc_arg() allows bpf_register_is_null() for nullable arguments w/o marking the underlying scalar register precise. Hence a checkpoint created on such a path would prune against arbitrary scalar value. Fixes: 3bda08b63670 ("bpf: Allow NULL buffers in bpf_dynptr_slice(_rw)") Signed-off-by: Eduard Zingerman Link: https://lore.kernel.org/r/20260904-register-is-null-precise-fixes-v1-5-0f5a360ff15d@gmail.com Signed-off-by: Alexei Starovoitov --- tools/pcmcia/.gitignore | 2 ++ tools/pcmcia/Makefile | 10 ++++++++++ tools/pcmcia/crc32hash.c | 33 +++++++++++++++++++++++++++++++++ 3 files changed, 45 insertions(+) create mode 100644 tools/pcmcia/.gitignore create mode 100644 tools/pcmcia/Makefile create mode 100644 tools/pcmcia/crc32hash.c (limited to 'tools/pcmcia') diff --git a/tools/pcmcia/.gitignore b/tools/pcmcia/.gitignore new file mode 100644 index 000000000..94cb97b77 --- /dev/null +++ b/tools/pcmcia/.gitignore @@ -0,0 +1,2 @@ +# SPDX-License-Identifier: GPL-2.0-only +crc32hash diff --git a/tools/pcmcia/Makefile b/tools/pcmcia/Makefile new file mode 100644 index 000000000..eae24df1d --- /dev/null +++ b/tools/pcmcia/Makefile @@ -0,0 +1,10 @@ +# SPDX-License-Identifier: GPL-2.0 +CC := $(CROSS_COMPILE)gcc +CFLAGS := -I../../usr/include + +PROGS := crc32hash + +all: $(PROGS) + +clean: + rm -fr $(PROGS) diff --git a/tools/pcmcia/crc32hash.c b/tools/pcmcia/crc32hash.c new file mode 100644 index 000000000..1a18da9cb --- /dev/null +++ b/tools/pcmcia/crc32hash.c @@ -0,0 +1,33 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* crc32hash.c - derived from linux/lib/crc32.c, GNU GPL v2 */ +/* Usage example: +$ ./crc32hash "Dual Speed" +*/ + +#include +#include +#include +#include + +static unsigned int crc32(unsigned char const *p, unsigned int len) +{ + int i; + unsigned int crc = 0; + while (len--) { + crc ^= *p++; + for (i = 0; i < 8; i++) + crc = (crc >> 1) ^ ((crc & 1) ? 0xedb88320 : 0); + } + return crc; +} + +int main(int argc, char **argv) { + unsigned int result; + if (argc != 2) { + printf("no string passed as argument\n"); + return -1; + } + result = crc32((unsigned char const *)argv[1], strlen(argv[1])); + printf("0x%x\n", result); + return 0; +} -- cgit v1.3.1