kernel/linux.git/net/bpf, branch linux-5.9.y

treewide: Use fallthrough pseudo-keyword

2020-08-23T22:36:59+00:00

Replace the existing /* fall through */ comments and its variants with the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary fall-through markings when it is the case. [1] https://www.kernel.org/doc/html/v5.7/process/deprecated.html?highlight=fallthrough#implicit-switch-case-fall-through Signed-off-by: Gustavo A. R. Silva

bpf: Allow to specify ifindex for skb in bpf_prog_test_run_skb

2020-08-03T21:32:23+00:00

Now skb->dev is unconditionally set to the loopback device in current net namespace. But if we want to test bpf program which contains code branch based on ifindex condition (eg filters out localhost packets) it is useful to allow specifying of ifindex from userspace. This patch adds such option through ctx_in (__sk_buff) parameter. Signed-off-by: Dmitry Yakunin Signed-off-by: Daniel Borkmann Link: https://lore.kernel.org/bpf/20200803090545.82046-3-zeil@yandex-team.ru

bpf: Setup socket family and addresses in bpf_prog_test_run_skb

2020-08-03T21:31:59+00:00

Now it's impossible to test all branches of cgroup_skb bpf program which accesses skb->family and skb->{local,remote}_ip{4,6} fields because they are zeroed during socket allocation. This commit fills socket family and addresses from related fields in constructed skb. Signed-off-by: Dmitry Yakunin Signed-off-by: Daniel Borkmann Link: https://lore.kernel.org/bpf/20200803090545.82046-2-zeil@yandex-team.ru

bpf: Add tests for PTR_TO_BTF_ID vs. null comparison

2020-06-30T20:21:29+00:00

Add two tests for PTR_TO_BTF_ID vs. null ptr comparison, one for PTR_TO_BTF_ID in the ctx structure and the other for PTR_TO_BTF_ID after one level pointer chasing. In both cases, the test ensures condition is not removed. For example, for this test struct bpf_fentry_test_t { struct bpf_fentry_test_t *a; }; int BPF_PROG(test7, struct bpf_fentry_test_t *arg) { if (arg == 0) test7_result = 1; return 0; } Before the previous verifier change, we have xlated codes: int test7(long long unsigned int * ctx): ; int BPF_PROG(test7, struct bpf_fentry_test_t *arg) 0: (79) r1 = *(u64 *)(r1 +0) ; int BPF_PROG(test7, struct bpf_fentry_test_t *arg) 1: (b4) w0 = 0 2: (95) exit After the previous verifier change, we have: int test7(long long unsigned int * ctx): ; int BPF_PROG(test7, struct bpf_fentry_test_t *arg) 0: (79) r1 = *(u64 *)(r1 +0) ; if (arg == 0) 1: (55) if r1 != 0x0 goto pc+4 ; test7_result = 1; 2: (18) r1 = map[id:6][0]+48 4: (b7) r2 = 1 5: (7b) *(u64 *)(r1 +0) = r2 ; int BPF_PROG(test7, struct bpf_fentry_test_t *arg) 6: (b4) w0 = 0 7: (95) exit Signed-off-by: Yonghong Song Signed-off-by: Daniel Borkmann Acked-by: John Fastabend Acked-by: Andrii Nakryiko Link: https://lore.kernel.org/bpf/20200630171241.2523875-1-yhs@fb.com

bpf: Fix too large copy from user in bpf_test_init

2020-05-19T15:56:34+00:00

Commit bc56c919fce7 ("bpf: Add xdp.frame_sz in bpf_prog_test_run_xdp().") recently changed bpf_prog_test_run_xdp() to use larger frames for XDP in order to test tail growing frames (via bpf_xdp_adjust_tail) and to have memory backing frame better resemble drivers. The commit contains a bug, as it tries to copy the max data size from userspace, instead of the size provided by userspace. This cause XDP unit tests to fail sporadically with EFAULT, an unfortunate behavior. The fix is to only copy the size specified by userspace. Fixes: bc56c919fce7 ("bpf: Add xdp.frame_sz in bpf_prog_test_run_xdp().") Signed-off-by: Jesper Dangaard Brouer Signed-off-by: Daniel Borkmann Acked-by: Andrii Nakryiko Link: https://lore.kernel.org/bpf/158980712729.256597.6115007718472928659.stgit@firesoul

bpf: Add xdp.frame_sz in bpf_prog_test_run_xdp().

2020-05-15T04:21:56+00:00

Update the memory requirements, when adding xdp.frame_sz in BPF test_run function bpf_prog_test_run_xdp() which e.g. is used by XDP selftests. Specifically add the expected reserved tailroom, but also allocated a larger memory area to reflect that XDP frames usually comes in this format. Limit the provided packet data size to 4096 minus headroom + tailroom, as this also reflect a common 3520 bytes MTU limit with XDP. Note that bpf_test_init already use a memory allocation method that clears memory. Thus, this already guards against leaking uninit kernel memory. Signed-off-by: Jesper Dangaard Brouer Signed-off-by: Alexei Starovoitov Link: https://lore.kernel.org/bpf/158945349549.97035.15316291762482444006.stgit@firesoul

bpf: Fix build warning regarding missing prototypes

2020-03-28T17:13:18+00:00

Fix build warnings when building net/bpf/test_run.o with W=1 due to missing prototype for bpf_fentry_test{1..6}. Instead of declaring prototypes, turn off warnings with __diag_{push,ignore,pop} as pointed out by Alexei. Signed-off-by: Jean-Philippe Menil Signed-off-by: Daniel Borkmann Link: https://lore.kernel.org/bpf/20200327204713.28050-1-jpmenil@gmail.com

bpf: Add selftests for BPF_MODIFY_RETURN

2020-03-04T21:41:06+00:00

Test for two scenarios: * When the fmod_ret program returns 0, the original function should be called along with fentry and fexit programs. * When the fmod_ret program returns a non-zero value, the original function should not be called, no side effect should be observed and fentry and fexit programs should be called. The result from the kernel function call and whether a side-effect is observed is returned via the retval attr of the BPF_PROG_TEST_RUN (bpf) syscall. Signed-off-by: KP Singh Signed-off-by: Alexei Starovoitov Acked-by: Andrii Nakryiko Acked-by: Daniel Borkmann Link: https://lore.kernel.org/bpf/20200304191853.1529-8-kpsingh@chromium.org

bpf: Add test ops for BPF_PROG_TYPE_TRACING

2020-03-04T21:41:06+00:00

The current fexit and fentry tests rely on a different program to exercise the functions they attach to. Instead of doing this, implement the test operations for tracing which will also be used for BPF_MODIFY_RETURN in a subsequent patch. Also, clean up the fexit test to use the generated skeleton. Signed-off-by: KP Singh Signed-off-by: Alexei Starovoitov Acked-by: Andrii Nakryiko Acked-by: Daniel Borkmann Link: https://lore.kernel.org/bpf/20200304191853.1529-7-kpsingh@chromium.org

bpf: Add gso_size to __sk_buff

2020-03-04T00:23:59+00:00

BPF programs may want to know whether an skb is gso. The canonical answer is skb_is_gso(skb), which tests that gso_size != 0. Expose this field in the same manner as gso_segs. That field itself is not a sufficient signal, as the comment in skb_shared_info makes clear: gso_segs may be zero, e.g., from dodgy sources. Also prepare net/bpf/test_run for upcoming BPF_PROG_TEST_RUN tests of the feature. Signed-off-by: Willem de Bruijn Signed-off-by: Alexei Starovoitov Link: https://lore.kernel.org/bpf/20200303200503.226217-2-willemdebruijn.kernel@gmail.com