[PATCH AUTOSEL 4.9 05/48] netlink: Deal with ESRCH error in nlmsg_notify()

[PATCH AUTOSEL 4.9 05/48] netlink: Deal with ESRCH error in nlmsg_notify()

[Sasha Levin]

From: Yajun Deng <yajun.deng@linux.dev>

[ Upstream commit fef773fc8110d8124c73a5e6610f89e52814637d ]

Yonghong Song report:
The bpf selftest tc_bpf failed with latest bpf-next.
The following is the command to run and the result:
$ ./test_progs -n 132
[   40.947571] bpf_testmod: loading out-of-tree module taints kernel.
test_tc_bpf:PASS:test_tc_bpf__open_and_load 0 nsec
test_tc_bpf:PASS:bpf_tc_hook_create(BPF_TC_INGRESS) 0 nsec
test_tc_bpf:PASS:bpf_tc_hook_create invalid hook.attach_point 0 nsec
test_tc_bpf_basic:PASS:bpf_obj_get_info_by_fd 0 nsec
test_tc_bpf_basic:PASS:bpf_tc_attach 0 nsec
test_tc_bpf_basic:PASS:handle set 0 nsec
test_tc_bpf_basic:PASS:priority set 0 nsec
test_tc_bpf_basic:PASS:prog_id set 0 nsec
test_tc_bpf_basic:PASS:bpf_tc_attach replace mode 0 nsec
test_tc_bpf_basic:PASS:bpf_tc_query 0 nsec
test_tc_bpf_basic:PASS:handle set 0 nsec
test_tc_bpf_basic:PASS:priority set 0 nsec
test_tc_bpf_basic:PASS:prog_id set 0 nsec
libbpf: Kernel error message: Failed to send filter delete notification
test_tc_bpf_basic:FAIL:bpf_tc_detach unexpected error: -3 (errno 3)
test_tc_bpf:FAIL:test_tc_internal ingress unexpected error: -3 (errno 3)

The failure seems due to the commit
    cfdf0d9ae75b ("rtnetlink: use nlmsg_notify() in rtnetlink_send()")

Deal with ESRCH error in nlmsg_notify() even the report variable is zero.

Reported-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Yajun Deng <yajun.deng@linux.dev>
Link: https://lore.kernel.org/r/20210719051816.11762-1-yajun.deng@linux.dev
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 net/netlink/af_netlink.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/net/netlink/af_netlink.c b/net/netlink/af_netlink.c
index 541410f1c3b7..453b0efdc0d7 100644
--- a/net/netlink/af_netlink.c
+++ b/net/netlink/af_netlink.c
@@ -2409,13 +2409,15 @@ int nlmsg_notify(struct sock *sk, struct sk_buff *skb, u32 portid,
 		/* errors reported via destination sk->sk_err, but propagate
 		 * delivery errors if NETLINK_BROADCAST_ERROR flag is set */
 		err = nlmsg_multicast(sk, skb, exclude_portid, group, flags);
+		if (err == -ESRCH)
+			err = 0;
 	}
 
 	if (report) {
 		int err2;
 
 		err2 = nlmsg_unicast(sk, skb, portid);
-		if (!err || err == -ESRCH)
+		if (!err)
 			err = err2;
 	}
 
-- 
2.30.2

[PATCH AUTOSEL 4.9 13/48] bpf/tests: Fix copy-and-paste error in double word test

[Sasha Levin]

From: Johan Almbladh <johan.almbladh@anyfinetworks.com>

[ Upstream commit ae7f47041d928b1a2f28717d095b4153c63cbf6a ]

This test now operates on DW as stated instead of W, which was
already covered by another test.

Signed-off-by: Johan Almbladh <johan.almbladh@anyfinetworks.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20210721104058.3755254-1-johan.almbladh@anyfinetworks.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 lib/test_bpf.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/lib/test_bpf.c b/lib/test_bpf.c
index 960d4d627361..ed2ebf677457 100644
--- a/lib/test_bpf.c
+++ b/lib/test_bpf.c
@@ -4295,8 +4295,8 @@ static struct bpf_test tests[] = {
 		.u.insns_int = {
 			BPF_LD_IMM64(R0, 0),
 			BPF_LD_IMM64(R1, 0xffffffffffffffffLL),
-			BPF_STX_MEM(BPF_W, R10, R1, -40),
-			BPF_LDX_MEM(BPF_W, R0, R10, -40),
+			BPF_STX_MEM(BPF_DW, R10, R1, -40),
+			BPF_LDX_MEM(BPF_DW, R0, R10, -40),
 			BPF_EXIT_INSN(),
 		},
 		INTERNAL,
-- 
2.30.2

[PATCH AUTOSEL 4.9 14/48] bpf/tests: Do not PASS tests without actually testing the result

[Sasha Levin]

From: Johan Almbladh <johan.almbladh@anyfinetworks.com>

[ Upstream commit 2b7e9f25e590726cca76700ebdb10e92a7a72ca1 ]

Each test case can have a set of sub-tests, where each sub-test can
run the cBPF/eBPF test snippet with its own data_size and expected
result. Before, the end of the sub-test array was indicated by both
data_size and result being zero. However, most or all of the internal
eBPF tests has a data_size of zero already. When such a test also had
an expected value of zero, the test was never run but reported as
PASS anyway.

Now the test runner always runs the first sub-test, regardless of the
data_size and result values. The sub-test array zero-termination only
applies for any additional sub-tests.

There are other ways fix it of course, but this solution at least
removes the surprise of eBPF tests with a zero result always succeeding.

Signed-off-by: Johan Almbladh <johan.almbladh@anyfinetworks.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20210721103822.3755111-1-johan.almbladh@anyfinetworks.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 lib/test_bpf.c | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/lib/test_bpf.c b/lib/test_bpf.c
index ed2ebf677457..0c62275630fa 100644
--- a/lib/test_bpf.c
+++ b/lib/test_bpf.c
@@ -5744,7 +5744,14 @@ static int run_one(const struct bpf_prog *fp, struct bpf_test *test)
 		u64 duration;
 		u32 ret;
 
-		if (test->test[i].data_size == 0 &&
+		/*
+		 * NOTE: Several sub-tests may be present, in which case
+		 * a zero {data_size, result} tuple indicates the end of
+		 * the sub-test array. The first test is always run,
+		 * even if both data_size and result happen to be zero.
+		 */
+		if (i > 0 &&
+		    test->test[i].data_size == 0 &&
 		    test->test[i].result == 0)
 			break;
 
-- 
2.30.2

[PATCH AUTOSEL 4.9 29/48] bpf: Fix off-by-one in tail call count limiting

[Sasha Levin]

From: Johan Almbladh <johan.almbladh@anyfinetworks.com>

[ Upstream commit b61a28cf11d61f512172e673b8f8c4a6c789b425 ]

Before, the interpreter allowed up to MAX_TAIL_CALL_CNT + 1 tail calls.
Now precisely MAX_TAIL_CALL_CNT is allowed, which is in line with the
behavior of the x86 JITs.

Signed-off-by: Johan Almbladh <johan.almbladh@anyfinetworks.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20210728164741.350370-1-johan.almbladh@anyfinetworks.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 kernel/bpf/core.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/kernel/bpf/core.c b/kernel/bpf/core.c
index df2ebce927ec..3e1d03512a4f 100644
--- a/kernel/bpf/core.c
+++ b/kernel/bpf/core.c
@@ -774,7 +774,7 @@ static unsigned int __bpf_prog_run(void *ctx, const struct bpf_insn *insn)
 
 		if (unlikely(index >= array->map.max_entries))
 			goto out;
-		if (unlikely(tail_call_cnt > MAX_TAIL_CALL_CNT))
+		if (unlikely(tail_call_cnt >= MAX_TAIL_CALL_CNT))
 			goto out;
 
 		tail_call_cnt++;
-- 
2.30.2