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 --- drivers/md/dm-vdo/string-utils.c | 22 ++++++++++++++++++++++ 1 file changed, 22 insertions(+) create mode 100644 drivers/md/dm-vdo/string-utils.c (limited to 'drivers/md/dm-vdo/string-utils.c') diff --git a/drivers/md/dm-vdo/string-utils.c b/drivers/md/dm-vdo/string-utils.c new file mode 100644 index 000000000..71e44b468 --- /dev/null +++ b/drivers/md/dm-vdo/string-utils.c @@ -0,0 +1,22 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright 2023 Red Hat + */ + +#include "string-utils.h" + +char *vdo_append_to_buffer(char *buffer, char *buf_end, const char *fmt, ...) +{ + va_list args; + size_t n; + + va_start(args, fmt); + n = vsnprintf(buffer, buf_end - buffer, fmt, args); + if (n >= (size_t) (buf_end - buffer)) + buffer = buf_end; + else + buffer += n; + va_end(args); + + return buffer; +} -- cgit v1.3.1