From: Pu Lehui <pulehui@xxxxxxxxxx> [ Upstream commit 34de8e6e0e1f66e431abf4123934a2581cb5f133 ] When using bpftool to pin {PROG, MAP, LINK} without FILE, segmentation fault will occur. The reson is that the lack of FILE will cause strlen to trigger NULL pointer dereference. The corresponding stacktrace is shown below: do_pin do_pin_any do_pin_fd mount_bpffs_for_pin strlen(name) <- NULL pointer dereference Fix it by adding validation to the common process. Fixes: 75a1e792c335 ("tools: bpftool: Allow all prog/map handles for pinning objects") Signed-off-by: Pu Lehui <pulehui@xxxxxxxxxx> Signed-off-by: Daniel Borkmann <daniel@xxxxxxxxxxxxx> Reviewed-by: Quentin Monnet <quentin@xxxxxxxxxxxxx> Link: https://lore.kernel.org/bpf/20221102084034.3342995-1-pulehui@xxxxxxxxxxxxxxx Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- tools/bpf/bpftool/common.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/tools/bpf/bpftool/common.c b/tools/bpf/bpftool/common.c index 6ebf2b215ef4..eefa2b34e641 100644 --- a/tools/bpf/bpftool/common.c +++ b/tools/bpf/bpftool/common.c @@ -271,6 +271,9 @@ int do_pin_any(int argc, char **argv, int (*get_fd)(int *, char ***)) int err; int fd; + if (!REQ_ARGS(3)) + return -EINVAL; + fd = get_fd(&argc, &argv); if (fd < 0) return fd; -- 2.35.1