From 44a9f04e7f0a741a7e9e72387809ae1fdf6b2a4e Mon Sep 17 00:00:00 2001 From: Paul Chaignon Date: Tue, 7 Nov 2023 12:10:53 +0100 Subject: sys/linux: add null check BPF instructions This commit adds a new struct with two BPF instructions to perform a null check on a given pointer. It is then used to update our small ringbuf program to null check the ringbuf reserved data pointer as follows. u64 *e; e = bpf_ringbuf_reserve(&rb, sizeof(*e), 0); if (!e) return 0; [...] bpf_ringbuf_submit(e, 0); return 0; With this null check, our test case corresponding to this program now passes the verifier and is successfully loaded. Signed-off-by: Paul Chaignon --- sys/linux/test/bpf_helpers | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'sys/linux/test') diff --git a/sys/linux/test/bpf_helpers b/sys/linux/test/bpf_helpers index 598395ac2..9cd6682b9 100644 --- a/sys/linux/test/bpf_helpers +++ b/sys/linux/test/bpf_helpers @@ -25,4 +25,4 @@ r4 = bpf$PROG_LOAD(AUTO, &AUTO={0x3, AUTO, &AUTO=@framed={{AUTO, AUTO, AUTO, AUT r1 = bpf$MAP_CREATE_RINGBUF(AUTO, &AUTO={AUTO, AUTO, AUTO, 0x40000, AUTO, 0x0, 0x0, "00000000000000000000000000000000", 0x0, 0x0, 0x0, 0x0, 0x0, AUTO}, 0x48) -r2 = bpf$PROG_LOAD(AUTO, &AUTO={0x3, AUTO, &AUTO=@ringbuf={{AUTO, AUTO, AUTO, AUTO, 0x0, AUTO, AUTO, AUTO, 0x0}, {{AUTO, AUTO, AUTO, AUTO, r1, AUTO, AUTO, AUTO, AUTO}, {AUTO, AUTO, AUTO, AUTO, AUTO, AUTO, AUTO}, {AUTO, AUTO, AUTO, AUTO, AUTO, AUTO, AUTO}, {AUTO, AUTO, AUTO, AUTO}, {AUTO, AUTO, AUTO, AUTO, AUTO, AUTO, AUTO}}, [], {{AUTO, AUTO, AUTO, AUTO, AUTO, AUTO, AUTO}, {AUTO, AUTO, AUTO, AUTO, AUTO, AUTO, AUTO}, {AUTO, AUTO, AUTO, AUTO}, {AUTO, AUTO, AUTO, AUTO, AUTO, AUTO, AUTO}}, {AUTO, AUTO, AUTO, AUTO}}, &AUTO='GPL\x00', 0x0, 0x0, 0x0, 0x0, 0x0, "00000000000000000000000000000000", 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0}, 0xa0) +r2 = bpf$PROG_LOAD(AUTO, &AUTO={0x3, AUTO, &AUTO=@ringbuf={{AUTO, AUTO, AUTO, AUTO, 0x0, AUTO, AUTO, AUTO, 0x0}, {{AUTO, AUTO, AUTO, AUTO, r1, AUTO, AUTO, AUTO, AUTO}, {AUTO, AUTO, AUTO, AUTO, AUTO, AUTO, AUTO}, {AUTO, AUTO, AUTO, AUTO, AUTO, AUTO, AUTO}, {AUTO, AUTO, AUTO, AUTO}, {AUTO, AUTO, AUTO, AUTO, AUTO, AUTO, AUTO}}, {{AUTO, AUTO, AUTO, AUTO, AUTO, AUTO, AUTO}, {AUTO, AUTO, AUTO, AUTO}}, [], {{AUTO, AUTO, AUTO, AUTO, AUTO, AUTO, AUTO}, {AUTO, AUTO, AUTO, AUTO, AUTO, AUTO, AUTO}, {AUTO, AUTO, AUTO, AUTO}, {AUTO, AUTO, AUTO, AUTO, AUTO, AUTO, AUTO}}, {AUTO, AUTO, AUTO, AUTO}}, &AUTO='GPL\x00', 0x0, 0x0, 0x0, 0x0, 0x0, "00000000000000000000000000000000", 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0}, 0xa0) -- cgit mrf-deployment