From: Ruslan Semchenko Date: Thu, 12 Jun 2025 13:18:16 +0000 (+0300) Subject: tools/bpf_jit_disasm: Fix potential negative tpath index in get_exec_path() X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=af91af33c16853c569ca814124781b849886f007;p=thirdparty%2Fkernel%2Fstable.git tools/bpf_jit_disasm: Fix potential negative tpath index in get_exec_path() If readlink() fails, len will be -1, which can cause negative indexing and undefined behavior. This patch ensures that len is set to 0 on readlink failure, preventing such issues. Signed-off-by: Ruslan Semchenko Acked-by: Daniel Borkmann Link: https://lore.kernel.org/r/20250612131816.1870-1-uncleruc2075@gmail.com Signed-off-by: Alexei Starovoitov --- diff --git a/tools/bpf/bpf_jit_disasm.c b/tools/bpf/bpf_jit_disasm.c index 1baee9e2aba9..5ab8f80e2834 100644 --- a/tools/bpf/bpf_jit_disasm.c +++ b/tools/bpf/bpf_jit_disasm.c @@ -45,6 +45,8 @@ static void get_exec_path(char *tpath, size_t size) assert(path); len = readlink(path, tpath, size); + if (len < 0) + len = 0; tpath[len] = 0; free(path);