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/lib/vsprintf.c | 44 ++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 44 insertions(+) create mode 100644 tools/lib/vsprintf.c (limited to 'tools/lib/vsprintf.c') diff --git a/tools/lib/vsprintf.c b/tools/lib/vsprintf.c new file mode 100644 index 000000000..8780b4cda --- /dev/null +++ b/tools/lib/vsprintf.c @@ -0,0 +1,44 @@ +// SPDX-License-Identifier: GPL-2.0 +#include +#include +#include + +int vscnprintf(char *buf, size_t size, const char *fmt, va_list args) +{ + int i = vsnprintf(buf, size, fmt, args); + ssize_t ssize = size; + + return (i >= ssize) ? (ssize - 1) : i; +} + +int scnprintf(char * buf, size_t size, const char * fmt, ...) +{ + ssize_t ssize = size; + va_list args; + int i; + + va_start(args, fmt); + i = vsnprintf(buf, size, fmt, args); + va_end(args); + + return (i >= ssize) ? (ssize - 1) : i; +} + +int scnprintf_pad(char * buf, size_t size, const char * fmt, ...) +{ + ssize_t ssize = size; + va_list args; + int i; + + va_start(args, fmt); + i = vscnprintf(buf, size, fmt, args); + va_end(args); + + if (i < (int) size) { + for (; i < (int) size; i++) + buf[i] = ' '; + buf[i] = 0x0; + } + + return (i >= ssize) ? (ssize - 1) : i; +} -- cgit v1.3.1