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This patch ensures that len is set to 0 on readlink failure, preventing such issues. Signed-off-by: Ruslan Semchenko Acked-by: Daniel Borkmann --- tools/bpf/bpf_jit_disasm.c | 2 ++ 1 file changed, 2 insertions(+) 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); =20 len =3D readlink(path, tpath, size); + if (len < 0) + len =3D 0; tpath[len] =3D 0; =20 free(path); --=20 2.49.0