[PATCH AUTOSEL 5.4 114/459] bpftool: Don't crash on missing xlated program instructions

[PATCH AUTOSEL 5.4 114/459] bpftool: Don't crash on missing xlated program instructions

[Sasha Levin]

From: Toke Høiland-Jørgensen <toke@redhat.com>

[ Upstream commit d95f1e8b462c4372ac409886070bb8719d8a4d3a ]

Turns out the xlated program instructions can also be missing if
kptr_restrict sysctl is set. This means that the previous fix to check the
jited_prog_insns pointer was insufficient; add another check of the
xlated_prog_insns pointer as well.

Fixes: 5b79bcdf0362 ("bpftool: Don't crash on missing jited insns or ksyms")
Fixes: cae73f233923 ("bpftool: use bpf_program__get_prog_info_linear() in prog.c:do_dump()")
Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Quentin Monnet <quentin@isovalent.com>
Link: https://lore.kernel.org/bpf/20200206102906.112551-1-toke@redhat.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 tools/bpf/bpftool/prog.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/tools/bpf/bpftool/prog.c b/tools/bpf/bpftool/prog.c
index ea0bcd58bcb9a..2e388421c32f4 100644
--- a/tools/bpf/bpftool/prog.c
+++ b/tools/bpf/bpftool/prog.c
@@ -500,7 +500,7 @@ static int do_dump(int argc, char **argv)
 		buf = (unsigned char *)(info->jited_prog_insns);
 		member_len = info->jited_prog_len;
 	} else {	/* DUMP_XLATED */
-		if (info->xlated_prog_len == 0) {
+		if (info->xlated_prog_len == 0 || !info->xlated_prog_insns) {
 			p_err("error retrieving insn dump: kernel.kptr_restrict set?");
 			goto err_free;
 		}
-- 
2.20.1

[PATCH AUTOSEL 5.4 115/459] bpf, sockhash: Synchronize_rcu before free'ing map

[Sasha Levin]

From: Jakub Sitnicki <jakub@cloudflare.com>

[ Upstream commit 0b2dc83906cf1e694e48003eae5df8fa63f76fd9 ]

We need to have a synchronize_rcu before free'ing the sockhash because any
outstanding psock references will have a pointer to the map and when they
use it, this could trigger a use after free.

This is a sister fix for sockhash, following commit 2bb90e5cc90e ("bpf:
sockmap, synchronize_rcu before free'ing map") which addressed sockmap,
which comes from a manual audit.

Fixes: 604326b41a6fb ("bpf, sockmap: convert to generic sk_msg interface")
Signed-off-by: Jakub Sitnicki <jakub@cloudflare.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/20200206111652.694507-3-jakub@cloudflare.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 net/core/sock_map.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/net/core/sock_map.c b/net/core/sock_map.c
index 8998e356f4232..058422b932607 100644
--- a/net/core/sock_map.c
+++ b/net/core/sock_map.c
@@ -250,6 +250,7 @@ static void sock_map_free(struct bpf_map *map)
 	raw_spin_unlock_bh(&stab->lock);
 	rcu_read_unlock();
 
+	/* wait for psock readers accessing its map link */
 	synchronize_rcu();
 
 	bpf_map_area_free(stab->sks);
@@ -873,6 +874,9 @@ static void sock_hash_free(struct bpf_map *map)
 	}
 	rcu_read_unlock();
 
+	/* wait for psock readers accessing its map link */
+	synchronize_rcu();
+
 	bpf_map_area_free(htab->buckets);
 	kfree(htab);
 }
-- 
2.20.1

[PATCH AUTOSEL 5.4 116/459] bpf, sockmap: Check update requirements after locking

[Sasha Levin]

From: Lorenz Bauer <lmb@cloudflare.com>

[ Upstream commit 85b8ac01a421791d66c3a458a7f83cfd173fe3fa ]

It's currently possible to insert sockets in unexpected states into
a sockmap, due to a TOCTTOU when updating the map from a syscall.
sock_map_update_elem checks that sk->sk_state == TCP_ESTABLISHED,
locks the socket and then calls sock_map_update_common. At this
point, the socket may have transitioned into another state, and
the earlier assumptions don't hold anymore. Crucially, it's
conceivable (though very unlikely) that a socket has become unhashed.
This breaks the sockmap's assumption that it will get a callback
via sk->sk_prot->unhash.

Fix this by checking the (fixed) sk_type and sk_protocol without the
lock, followed by a locked check of sk_state.

Unfortunately it's not possible to push the check down into
sock_(map|hash)_update_common, since BPF_SOCK_OPS_PASSIVE_ESTABLISHED_CB
run before the socket has transitioned from TCP_SYN_RECV into
TCP_ESTABLISHED.

Fixes: 604326b41a6f ("bpf, sockmap: convert to generic sk_msg interface")
Signed-off-by: Lorenz Bauer <lmb@cloudflare.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Jakub Sitnicki <jakub@cloudflare.com>
Link: https://lore.kernel.org/bpf/20200207103713.28175-1-lmb@cloudflare.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 net/core/sock_map.c | 16 ++++++++++------
 1 file changed, 10 insertions(+), 6 deletions(-)

diff --git a/net/core/sock_map.c b/net/core/sock_map.c
index 058422b932607..b16ff3b8c6503 100644
--- a/net/core/sock_map.c
+++ b/net/core/sock_map.c
@@ -417,14 +417,16 @@ static int sock_map_update_elem(struct bpf_map *map, void *key,
 		ret = -EINVAL;
 		goto out;
 	}
-	if (!sock_map_sk_is_suitable(sk) ||
-	    sk->sk_state != TCP_ESTABLISHED) {
+	if (!sock_map_sk_is_suitable(sk)) {
 		ret = -EOPNOTSUPP;
 		goto out;
 	}
 
 	sock_map_sk_acquire(sk);
-	ret = sock_map_update_common(map, idx, sk, flags);
+	if (sk->sk_state != TCP_ESTABLISHED)
+		ret = -EOPNOTSUPP;
+	else
+		ret = sock_map_update_common(map, idx, sk, flags);
 	sock_map_sk_release(sk);
 out:
 	fput(sock->file);
@@ -740,14 +742,16 @@ static int sock_hash_update_elem(struct bpf_map *map, void *key,
 		ret = -EINVAL;
 		goto out;
 	}
-	if (!sock_map_sk_is_suitable(sk) ||
-	    sk->sk_state != TCP_ESTABLISHED) {
+	if (!sock_map_sk_is_suitable(sk)) {
 		ret = -EOPNOTSUPP;
 		goto out;
 	}
 
 	sock_map_sk_acquire(sk);
-	ret = sock_hash_update_common(map, key, sk, flags);
+	if (sk->sk_state != TCP_ESTABLISHED)
+		ret = -EOPNOTSUPP;
+	else
+		ret = sock_hash_update_common(map, key, sk, flags);
 	sock_map_sk_release(sk);
 out:
 	fput(sock->file);
-- 
2.20.1

[PATCH AUTOSEL 5.4 117/459] bpf: Improve bucket_log calculation logic

[Sasha Levin]

From: Martin KaFai Lau <kafai@fb.com>

[ Upstream commit 88d6f130e5632bbf419a2e184ec7adcbe241260b ]

It was reported that the max_t, ilog2, and roundup_pow_of_two macros have
exponential effects on the number of states in the sparse checker.

This patch breaks them up by calculating the "nbuckets" first so that the
"bucket_log" only needs to take ilog2().

In addition, Linus mentioned:

  Patch looks good, but I'd like to point out that it's not just sparse.

  You can see it with a simple

    make net/core/bpf_sk_storage.i
    grep 'smap->bucket_log = ' net/core/bpf_sk_storage.i | wc

  and see the end result:

      1  365071 2686974

  That's one line (the assignment line) that is 2,686,974 characters in
  length.

  Now, sparse does happen to react particularly badly to that (I didn't
  look to why, but I suspect it's just that evaluating all the types
  that don't actually ever end up getting used ends up being much more
  expensive than it should be), but I bet it's not good for gcc either.

Fixes: 6ac99e8f23d4 ("bpf: Introduce bpf sk local storage")
Reported-by: Randy Dunlap <rdunlap@infradead.org>
Reported-by: Luc Van Oostenryck <luc.vanoostenryck@gmail.com>
Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Luc Van Oostenryck <luc.vanoostenryck@gmail.com>
Link: https://lore.kernel.org/bpf/20200207081810.3918919-1-kafai@fb.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 net/core/bpf_sk_storage.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/net/core/bpf_sk_storage.c b/net/core/bpf_sk_storage.c
index da5639a5bd3b9..0147b26f585a3 100644
--- a/net/core/bpf_sk_storage.c
+++ b/net/core/bpf_sk_storage.c
@@ -643,9 +643,10 @@ static struct bpf_map *bpf_sk_storage_map_alloc(union bpf_attr *attr)
 		return ERR_PTR(-ENOMEM);
 	bpf_map_init_from_attr(&smap->map, attr);
 
+	nbuckets = roundup_pow_of_two(num_possible_cpus());
 	/* Use at least 2 buckets, select_bucket() is undefined behavior with 1 bucket */
-	smap->bucket_log = max_t(u32, 1, ilog2(roundup_pow_of_two(num_possible_cpus())));
-	nbuckets = 1U << smap->bucket_log;
+	nbuckets = max_t(u32, 2, nbuckets);
+	smap->bucket_log = ilog2(nbuckets);
 	cost = sizeof(*smap->buckets) * nbuckets + sizeof(*smap);
 
 	ret = bpf_map_charge_init(&smap->map.memory, cost);
-- 
2.20.1

[PATCH AUTOSEL 5.4 118/459] bpf, sockmap: Don't sleep while holding RCU lock on tear-down

[Sasha Levin]

From: Jakub Sitnicki <jakub@cloudflare.com>

[ Upstream commit db6a5018b6e008c1d69c6628cdaa9541b8e70940 ]

rcu_read_lock is needed to protect access to psock inside sock_map_unref
when tearing down the map. However, we can't afford to sleep in lock_sock
while in RCU read-side critical section. Grab the RCU lock only after we
have locked the socket.

This fixes RCU warnings triggerable on a VM with 1 vCPU when free'ing a
sockmap/sockhash that contains at least one socket:

| =============================
| WARNING: suspicious RCU usage
| 5.5.0-04005-g8fc91b972b73 #450 Not tainted
| -----------------------------
| include/linux/rcupdate.h:272 Illegal context switch in RCU read-side critical section!
|
| other info that might help us debug this:
|
|
| rcu_scheduler_active = 2, debug_locks = 1
| 4 locks held by kworker/0:1/62:
|  #0: ffff88813b019748 ((wq_completion)events){+.+.}, at: process_one_work+0x1d7/0x5e0
|  #1: ffffc900000abe50 ((work_completion)(&map->work)){+.+.}, at: process_one_work+0x1d7/0x5e0
|  #2: ffffffff82065d20 (rcu_read_lock){....}, at: sock_map_free+0x5/0x170
|  #3: ffff8881368c5df8 (&stab->lock){+...}, at: sock_map_free+0x64/0x170
|
| stack backtrace:
| CPU: 0 PID: 62 Comm: kworker/0:1 Not tainted 5.5.0-04005-g8fc91b972b73 #450
| Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS ?-20190727_073836-buildvm-ppc64le-16.ppc.fedoraproject.org-3.fc31 04/01/2014
| Workqueue: events bpf_map_free_deferred
| Call Trace:
|  dump_stack+0x71/0xa0
|  ___might_sleep+0x105/0x190
|  lock_sock_nested+0x28/0x90
|  sock_map_free+0x95/0x170
|  bpf_map_free_deferred+0x58/0x80
|  process_one_work+0x260/0x5e0
|  worker_thread+0x4d/0x3e0
|  kthread+0x108/0x140
|  ? process_one_work+0x5e0/0x5e0
|  ? kthread_park+0x90/0x90
|  ret_from_fork+0x3a/0x50

| =============================
| WARNING: suspicious RCU usage
| 5.5.0-04005-g8fc91b972b73-dirty #452 Not tainted
| -----------------------------
| include/linux/rcupdate.h:272 Illegal context switch in RCU read-side critical section!
|
| other info that might help us debug this:
|
|
| rcu_scheduler_active = 2, debug_locks = 1
| 4 locks held by kworker/0:1/62:
|  #0: ffff88813b019748 ((wq_completion)events){+.+.}, at: process_one_work+0x1d7/0x5e0
|  #1: ffffc900000abe50 ((work_completion)(&map->work)){+.+.}, at: process_one_work+0x1d7/0x5e0
|  #2: ffffffff82065d20 (rcu_read_lock){....}, at: sock_hash_free+0x5/0x1d0
|  #3: ffff888139966e00 (&htab->buckets[i].lock){+...}, at: sock_hash_free+0x92/0x1d0
|
| stack backtrace:
| CPU: 0 PID: 62 Comm: kworker/0:1 Not tainted 5.5.0-04005-g8fc91b972b73-dirty #452
| Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS ?-20190727_073836-buildvm-ppc64le-16.ppc.fedoraproject.org-3.fc31 04/01/2014
| Workqueue: events bpf_map_free_deferred
| Call Trace:
|  dump_stack+0x71/0xa0
|  ___might_sleep+0x105/0x190
|  lock_sock_nested+0x28/0x90
|  sock_hash_free+0xec/0x1d0
|  bpf_map_free_deferred+0x58/0x80
|  process_one_work+0x260/0x5e0
|  worker_thread+0x4d/0x3e0
|  kthread+0x108/0x140
|  ? process_one_work+0x5e0/0x5e0
|  ? kthread_park+0x90/0x90
|  ret_from_fork+0x3a/0x50

Fixes: 7e81a3530206 ("bpf: Sockmap, ensure sock lock held during tear down")
Signed-off-by: Jakub Sitnicki <jakub@cloudflare.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/20200206111652.694507-2-jakub@cloudflare.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 net/core/sock_map.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/net/core/sock_map.c b/net/core/sock_map.c
index b16ff3b8c6503..085cef5857bbf 100644
--- a/net/core/sock_map.c
+++ b/net/core/sock_map.c
@@ -234,7 +234,6 @@ static void sock_map_free(struct bpf_map *map)
 	int i;
 
 	synchronize_rcu();
-	rcu_read_lock();
 	raw_spin_lock_bh(&stab->lock);
 	for (i = 0; i < stab->map.max_entries; i++) {
 		struct sock **psk = &stab->sks[i];
@@ -243,12 +242,13 @@ static void sock_map_free(struct bpf_map *map)
 		sk = xchg(psk, NULL);
 		if (sk) {
 			lock_sock(sk);
+			rcu_read_lock();
 			sock_map_unref(sk, psk);
+			rcu_read_unlock();
 			release_sock(sk);
 		}
 	}
 	raw_spin_unlock_bh(&stab->lock);
-	rcu_read_unlock();
 
 	/* wait for psock readers accessing its map link */
 	synchronize_rcu();
@@ -864,19 +864,19 @@ static void sock_hash_free(struct bpf_map *map)
 	int i;
 
 	synchronize_rcu();
-	rcu_read_lock();
 	for (i = 0; i < htab->buckets_num; i++) {
 		bucket = sock_hash_select_bucket(htab, i);
 		raw_spin_lock_bh(&bucket->lock);
 		hlist_for_each_entry_safe(elem, node, &bucket->head, node) {
 			hlist_del_rcu(&elem->node);
 			lock_sock(elem->sk);
+			rcu_read_lock();
 			sock_map_unref(elem->sk, elem);
+			rcu_read_unlock();
 			release_sock(elem->sk);
 		}
 		raw_spin_unlock_bh(&bucket->lock);
 	}
-	rcu_read_unlock();
 
 	/* wait for psock readers accessing its map link */
 	synchronize_rcu();
-- 
2.20.1

[PATCH AUTOSEL 5.4 186/459] samples/bpf: Set -fno-stack-protector when building BPF programs

[Sasha Levin]

From: Toke Høiland-Jørgensen <toke@redhat.com>

[ Upstream commit 450278977acbf494a20367c22fbb38729772d1fc ]

It seems Clang can in some cases turn on stack protection by default, which
doesn't work with BPF. This was reported once before[0], but it seems the
flag to explicitly turn off the stack protector wasn't added to the
Makefile, so do that now.

The symptom of this is compile errors like the following:

error: <unknown>:0:0: in function bpf_prog1 i32 (%struct.__sk_buff*): A call to built-in function '__stack_chk_fail' is not supported.

[0] https://www.spinics.net/lists/netdev/msg556400.html

Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20191216103819.359535-1-toke@redhat.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 samples/bpf/Makefile | 1 +
 1 file changed, 1 insertion(+)

diff --git a/samples/bpf/Makefile b/samples/bpf/Makefile
index e7ad48c605e0f..6d1df7117e117 100644
--- a/samples/bpf/Makefile
+++ b/samples/bpf/Makefile
@@ -219,6 +219,7 @@ BTF_LLVM_PROBE := $(shell echo "int main() { return 0; }" | \
 			  readelf -S ./llvm_btf_verify.o | grep BTF; \
 			  /bin/rm -f ./llvm_btf_verify.o)
 
+BPF_EXTRA_CFLAGS += -fno-stack-protector
 ifneq ($(BTF_LLVM_PROBE),)
 	EXTRA_CFLAGS += -g
 else
-- 
2.20.1

[PATCH AUTOSEL 5.4 227/459] bpf: Print error message for bpftool cgroup show

[Sasha Levin]

From: Hechao Li <hechaol@fb.com>

[ Upstream commit 1162f844030ac1ac7321b5e8f6c9badc7a11428f ]

Currently, when bpftool cgroup show <path> has an error, no error
message is printed. This is confusing because the user may think the
result is empty.

Before the change:

$ bpftool cgroup show /sys/fs/cgroup
ID       AttachType      AttachFlags     Name
$ echo $?
255

After the change:
$ ./bpftool cgroup show /sys/fs/cgroup
Error: can't query bpf programs attached to /sys/fs/cgroup: Operation
not permitted

v2: Rename check_query_cgroup_progs to cgroup_has_attached_progs

Signed-off-by: Hechao Li <hechaol@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20191224011742.3714301-1-hechaol@fb.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 tools/bpf/bpftool/cgroup.c | 56 ++++++++++++++++++++++++++------------
 1 file changed, 39 insertions(+), 17 deletions(-)

diff --git a/tools/bpf/bpftool/cgroup.c b/tools/bpf/bpftool/cgroup.c
index 1ef45e55039e1..2f017caa678dc 100644
--- a/tools/bpf/bpftool/cgroup.c
+++ b/tools/bpf/bpftool/cgroup.c
@@ -117,6 +117,25 @@ static int count_attached_bpf_progs(int cgroup_fd, enum bpf_attach_type type)
 	return prog_cnt;
 }
 
+static int cgroup_has_attached_progs(int cgroup_fd)
+{
+	enum bpf_attach_type type;
+	bool no_prog = true;
+
+	for (type = 0; type < __MAX_BPF_ATTACH_TYPE; type++) {
+		int count = count_attached_bpf_progs(cgroup_fd, type);
+
+		if (count < 0 && errno != EINVAL)
+			return -1;
+
+		if (count > 0) {
+			no_prog = false;
+			break;
+		}
+	}
+
+	return no_prog ? 0 : 1;
+}
 static int show_attached_bpf_progs(int cgroup_fd, enum bpf_attach_type type,
 				   int level)
 {
@@ -161,6 +180,7 @@ static int show_attached_bpf_progs(int cgroup_fd, enum bpf_attach_type type,
 static int do_show(int argc, char **argv)
 {
 	enum bpf_attach_type type;
+	int has_attached_progs;
 	const char *path;
 	int cgroup_fd;
 	int ret = -1;
@@ -192,6 +212,16 @@ static int do_show(int argc, char **argv)
 		goto exit;
 	}
 
+	has_attached_progs = cgroup_has_attached_progs(cgroup_fd);
+	if (has_attached_progs < 0) {
+		p_err("can't query bpf programs attached to %s: %s",
+		      path, strerror(errno));
+		goto exit_cgroup;
+	} else if (!has_attached_progs) {
+		ret = 0;
+		goto exit_cgroup;
+	}
+
 	if (json_output)
 		jsonw_start_array(json_wtr);
 	else
@@ -212,6 +242,7 @@ static int do_show(int argc, char **argv)
 	if (json_output)
 		jsonw_end_array(json_wtr);
 
+exit_cgroup:
 	close(cgroup_fd);
 exit:
 	return ret;
@@ -228,7 +259,7 @@ static int do_show_tree_fn(const char *fpath, const struct stat *sb,
 			   int typeflag, struct FTW *ftw)
 {
 	enum bpf_attach_type type;
-	bool skip = true;
+	int has_attached_progs;
 	int cgroup_fd;
 
 	if (typeflag != FTW_D)
@@ -240,22 +271,13 @@ static int do_show_tree_fn(const char *fpath, const struct stat *sb,
 		return SHOW_TREE_FN_ERR;
 	}
 
-	for (type = 0; type < __MAX_BPF_ATTACH_TYPE; type++) {
-		int count = count_attached_bpf_progs(cgroup_fd, type);
-
-		if (count < 0 && errno != EINVAL) {
-			p_err("can't query bpf programs attached to %s: %s",
-			      fpath, strerror(errno));
-			close(cgroup_fd);
-			return SHOW_TREE_FN_ERR;
-		}
-		if (count > 0) {
-			skip = false;
-			break;
-		}
-	}
-
-	if (skip) {
+	has_attached_progs = cgroup_has_attached_progs(cgroup_fd);
+	if (has_attached_progs < 0) {
+		p_err("can't query bpf programs attached to %s: %s",
+		      fpath, strerror(errno));
+		close(cgroup_fd);
+		return SHOW_TREE_FN_ERR;
+	} else if (!has_attached_progs) {
 		close(cgroup_fd);
 		return 0;
 	}
-- 
2.20.1

[PATCH AUTOSEL 5.4 248/459] tools lib api fs: Fix gcc9 stringop-truncation compilation error

[Sasha Levin]

From: Andrey Zhizhikin <andrey.z@gmail.com>

[ Upstream commit 6794200fa3c9c3e6759dae099145f23e4310f4f7 ]

GCC9 introduced string hardening mechanisms, which exhibits the error
during fs api compilation:

error: '__builtin_strncpy' specified bound 4096 equals destination size
[-Werror=stringop-truncation]

This comes when the length of copy passed to strncpy is is equal to
destination size, which could potentially lead to buffer overflow.

There is a need to mitigate this potential issue by limiting the size of
destination by 1 and explicitly terminate the destination with NULL.

Signed-off-by: Andrey Zhizhikin <andrey.zhizhikin@leica-geosystems.com>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Andrii Nakryiko <andriin@fb.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Kefeng Wang <wangkefeng.wang@huawei.com>
Cc: Martin KaFai Lau <kafai@fb.com>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Cc: Song Liu <songliubraving@fb.com>
Cc: Yonghong Song <yhs@fb.com>
Cc: bpf@vger.kernel.org
Cc: netdev@vger.kernel.org
Link: http://lore.kernel.org/lkml/20191211080109.18765-1-andrey.zhizhikin@leica-geosystems.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 tools/lib/api/fs/fs.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/tools/lib/api/fs/fs.c b/tools/lib/api/fs/fs.c
index 7aba8243a0e7c..bd021a0eeef8c 100644
--- a/tools/lib/api/fs/fs.c
+++ b/tools/lib/api/fs/fs.c
@@ -210,6 +210,7 @@ static bool fs__env_override(struct fs *fs)
 	size_t name_len = strlen(fs->name);
 	/* name + "_PATH" + '\0' */
 	char upper_name[name_len + 5 + 1];
+
 	memcpy(upper_name, fs->name, name_len);
 	mem_toupper(upper_name, name_len);
 	strcpy(&upper_name[name_len], "_PATH");
@@ -219,7 +220,8 @@ static bool fs__env_override(struct fs *fs)
 		return false;
 
 	fs->found = true;
-	strncpy(fs->path, override_path, sizeof(fs->path));
+	strncpy(fs->path, override_path, sizeof(fs->path) - 1);
+	fs->path[sizeof(fs->path) - 1] = '\0';
 	return true;
 }
 
-- 
2.20.1

[PATCH AUTOSEL 5.4 307/459] bpf: Return -EBADRQC for invalid map type in __bpf_tx_xdp_map

[Sasha Levin]

From: Li RongQing <lirongqing@baidu.com>

[ Upstream commit 0a29275b6300f39f78a87f2038bbfe5bdbaeca47 ]

A negative value should be returned if map->map_type is invalid
although that is impossible now, but if we run into such situation
in future, then xdpbuff could be leaked.

Daniel Borkmann suggested:

-EBADRQC should be returned to stay consistent with generic XDP
for the tracepoint output and not to be confused with -EOPNOTSUPP
from other locations like dev_map_enqueue() when ndo_xdp_xmit is
missing and such.

Suggested-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Li RongQing <lirongqing@baidu.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/1578618277-18085-1-git-send-email-lirongqing@baidu.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 net/core/filter.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/net/core/filter.c b/net/core/filter.c
index 1a78d64096bbd..d59dbc88fef5d 100644
--- a/net/core/filter.c
+++ b/net/core/filter.c
@@ -3543,7 +3543,7 @@ static int __bpf_tx_xdp_map(struct net_device *dev_rx, void *fwd,
 		return err;
 	}
 	default:
-		break;
+		return -EBADRQC;
 	}
 	return 0;
 }
-- 
2.20.1

[PATCH AUTOSEL 5.4 376/459] bpf, btf: Always output invariant hit in pahole DWARF to BTF transform

[Sasha Levin]

From: Chris Down <chris@chrisdown.name>

[ Upstream commit 2a67a6ccb01f21b854715d86ff6432a18b97adb3 ]

When trying to compile with CONFIG_DEBUG_INFO_BTF enabled, I got this
error:

    % make -s
    Failed to generate BTF for vmlinux
    Try to disable CONFIG_DEBUG_INFO_BTF
    make[3]: *** [vmlinux] Error 1

Compiling again without -s shows the true error (that pahole is
missing), but since this is fatal, we should show the error
unconditionally on stderr as well, not silence it using the `info`
function. With this patch:

    % make -s
    BTF: .tmp_vmlinux.btf: pahole (pahole) is not available
    Failed to generate BTF for vmlinux
    Try to disable CONFIG_DEBUG_INFO_BTF
    make[3]: *** [vmlinux] Error 1

Signed-off-by: Chris Down <chris@chrisdown.name>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20200122000110.GA310073@chrisdown.name
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 scripts/link-vmlinux.sh | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/scripts/link-vmlinux.sh b/scripts/link-vmlinux.sh
index 4363799403561..408b5c0b99b1b 100755
--- a/scripts/link-vmlinux.sh
+++ b/scripts/link-vmlinux.sh
@@ -108,13 +108,13 @@ gen_btf()
 	local bin_arch
 
 	if ! [ -x "$(command -v ${PAHOLE})" ]; then
-		info "BTF" "${1}: pahole (${PAHOLE}) is not available"
+		echo >&2 "BTF: ${1}: pahole (${PAHOLE}) is not available"
 		return 1
 	fi
 
 	pahole_ver=$(${PAHOLE} --version | sed -E 's/v([0-9]+)\.([0-9]+)/\1\2/')
 	if [ "${pahole_ver}" -lt "113" ]; then
-		info "BTF" "${1}: pahole version $(${PAHOLE} --version) is too old, need at least v1.13"
+		echo >&2 "BTF: ${1}: pahole version $(${PAHOLE} --version) is too old, need at least v1.13"
 		return 1
 	fi
 
-- 
2.20.1

[PATCH AUTOSEL 5.4 397/459] selftests: bpf: Reset global state between reuseport test runs

[Sasha Levin]

From: Lorenz Bauer <lmb@cloudflare.com>

[ Upstream commit 51bad0f05616c43d6d34b0a19bcc9bdab8e8fb39 ]

Currently, there is a lot of false positives if a single reuseport test
fails. This is because expected_results and the result map are not cleared.

Zero both after individual test runs, which fixes the mentioned false
positives.

Fixes: 91134d849a0e ("bpf: Test BPF_PROG_TYPE_SK_REUSEPORT")
Signed-off-by: Lorenz Bauer <lmb@cloudflare.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Jakub Sitnicki <jakub@cloudflare.com>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/20200124112754.19664-5-lmb@cloudflare.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 .../selftests/bpf/test_select_reuseport.c        | 16 ++++++++++++++--
 1 file changed, 14 insertions(+), 2 deletions(-)

diff --git a/tools/testing/selftests/bpf/test_select_reuseport.c b/tools/testing/selftests/bpf/test_select_reuseport.c
index 7566c13eb51a7..079d0f5a29091 100644
--- a/tools/testing/selftests/bpf/test_select_reuseport.c
+++ b/tools/testing/selftests/bpf/test_select_reuseport.c
@@ -30,7 +30,7 @@
 #define REUSEPORT_ARRAY_SIZE 32
 
 static int result_map, tmp_index_ovr_map, linum_map, data_check_map;
-static enum result expected_results[NR_RESULTS];
+static __u32 expected_results[NR_RESULTS];
 static int sk_fds[REUSEPORT_ARRAY_SIZE];
 static int reuseport_array, outer_map;
 static int select_by_skb_data_prog;
@@ -662,7 +662,19 @@ static void setup_per_test(int type, unsigned short family, bool inany)
 
 static void cleanup_per_test(void)
 {
-	int i, err;
+	int i, err, zero = 0;
+
+	memset(expected_results, 0, sizeof(expected_results));
+
+	for (i = 0; i < NR_RESULTS; i++) {
+		err = bpf_map_update_elem(result_map, &i, &zero, BPF_ANY);
+		RET_IF(err, "reset elem in result_map",
+		       "i:%u err:%d errno:%d\n", i, err, errno);
+	}
+
+	err = bpf_map_update_elem(linum_map, &zero, &zero, BPF_ANY);
+	RET_IF(err, "reset line number in linum_map", "err:%d errno:%d\n",
+	       err, errno);
 
 	for (i = 0; i < REUSEPORT_ARRAY_SIZE; i++)
 		close(sk_fds[i]);
-- 
2.20.1

[PATCH AUTOSEL 5.4 415/459] bpf: map_seq_next should always increase position index

[Sasha Levin]

From: Vasily Averin <vvs@virtuozzo.com>

[ Upstream commit 90435a7891a2259b0f74c5a1bc5600d0d64cba8f ]

If seq_file .next fuction does not change position index,
read after some lseek can generate an unexpected output.

See also: https://bugzilla.kernel.org/show_bug.cgi?id=206283

v1 -> v2: removed missed increment in end of function

Signed-off-by: Vasily Averin <vvs@virtuozzo.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/eca84fdd-c374-a154-d874-6c7b55fc3bc4@virtuozzo.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 kernel/bpf/inode.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/kernel/bpf/inode.c b/kernel/bpf/inode.c
index a70f7209cda3f..218c09ff6a273 100644
--- a/kernel/bpf/inode.c
+++ b/kernel/bpf/inode.c
@@ -196,6 +196,7 @@ static void *map_seq_next(struct seq_file *m, void *v, loff_t *pos)
 	void *key = map_iter(m)->key;
 	void *prev_key;
 
+	(*pos)++;
 	if (map_iter(m)->done)
 		return NULL;
 
@@ -208,8 +209,6 @@ static void *map_seq_next(struct seq_file *m, void *v, loff_t *pos)
 		map_iter(m)->done = true;
 		return NULL;
 	}
-
-	++(*pos);
 	return key;
 }
 
-- 
2.20.1

[PATCH AUTOSEL 5.4 430/459] powerpc: Do not consider weak unresolved symbol relocations as bad

[Sasha Levin]

From: Alexandre Ghiti <alex@ghiti.fr>

[ Upstream commit 43e76cd368fbb67e767da5363ffeaa3989993c8c ]

Commit 8580ac9404f6 ("bpf: Process in-kernel BTF") introduced two weak
symbols that may be unresolved at link time which result in an absolute
relocation to 0. relocs_check.sh emits the following warning:

"WARNING: 2 bad relocations
c000000001a41478 R_PPC64_ADDR64    _binary__btf_vmlinux_bin_start
c000000001a41480 R_PPC64_ADDR64    _binary__btf_vmlinux_bin_end"

whereas those relocations are legitimate even for a relocatable kernel
compiled with -pie option.

relocs_check.sh already excluded some weak unresolved symbols explicitly:
remove those hardcoded symbols and add some logic that parses the symbols
using nm, retrieves all the weak unresolved symbols and excludes those from
the list of the potential bad relocations.

Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Alexandre Ghiti <alex@ghiti.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200118170335.21440-1-alex@ghiti.fr
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 arch/powerpc/Makefile.postlink     |  4 ++--
 arch/powerpc/tools/relocs_check.sh | 20 ++++++++++++--------
 2 files changed, 14 insertions(+), 10 deletions(-)

diff --git a/arch/powerpc/Makefile.postlink b/arch/powerpc/Makefile.postlink
index 134f12f89b92b..2268396ff4bba 100644
--- a/arch/powerpc/Makefile.postlink
+++ b/arch/powerpc/Makefile.postlink
@@ -17,11 +17,11 @@ quiet_cmd_head_check = CHKHEAD $@
 quiet_cmd_relocs_check = CHKREL  $@
 ifdef CONFIG_PPC_BOOK3S_64
       cmd_relocs_check =						\
-	$(CONFIG_SHELL) $(srctree)/arch/powerpc/tools/relocs_check.sh "$(OBJDUMP)" "$@" ; \
+	$(CONFIG_SHELL) $(srctree)/arch/powerpc/tools/relocs_check.sh "$(OBJDUMP)" "$(NM)" "$@" ; \
 	$(BASH) $(srctree)/arch/powerpc/tools/unrel_branch_check.sh "$(OBJDUMP)" "$@"
 else
       cmd_relocs_check =						\
-	$(CONFIG_SHELL) $(srctree)/arch/powerpc/tools/relocs_check.sh "$(OBJDUMP)" "$@"
+	$(CONFIG_SHELL) $(srctree)/arch/powerpc/tools/relocs_check.sh "$(OBJDUMP)" "$(NM)" "$@"
 endif
 
 # `@true` prevents complaint when there is nothing to be done
diff --git a/arch/powerpc/tools/relocs_check.sh b/arch/powerpc/tools/relocs_check.sh
index 7b9fe0a567cf3..014e00e74d2b6 100755
--- a/arch/powerpc/tools/relocs_check.sh
+++ b/arch/powerpc/tools/relocs_check.sh
@@ -10,14 +10,21 @@
 # based on relocs_check.pl
 # Copyright © 2009 IBM Corporation
 
-if [ $# -lt 2 ]; then
-	echo "$0 [path to objdump] [path to vmlinux]" 1>&2
+if [ $# -lt 3 ]; then
+	echo "$0 [path to objdump] [path to nm] [path to vmlinux]" 1>&2
 	exit 1
 fi
 
-# Have Kbuild supply the path to objdump so we handle cross compilation.
+# Have Kbuild supply the path to objdump and nm so we handle cross compilation.
 objdump="$1"
-vmlinux="$2"
+nm="$2"
+vmlinux="$3"
+
+# Remove from the bad relocations those that match an undefined weak symbol
+# which will result in an absolute relocation to 0.
+# Weak unresolved symbols are of that form in nm output:
+# "                  w _binary__btf_vmlinux_bin_end"
+undef_weak_symbols=$($nm "$vmlinux" | awk '$1 ~ /w/ { print $2 }')
 
 bad_relocs=$(
 $objdump -R "$vmlinux" |
@@ -26,8 +33,6 @@ $objdump -R "$vmlinux" |
 	# These relocations are okay
 	# On PPC64:
 	#	R_PPC64_RELATIVE, R_PPC64_NONE
-	#	R_PPC64_ADDR64 mach_<name>
-	#	R_PPC64_ADDR64 __crc_<name>
 	# On PPC:
 	#	R_PPC_RELATIVE, R_PPC_ADDR16_HI,
 	#	R_PPC_ADDR16_HA,R_PPC_ADDR16_LO,
@@ -39,8 +44,7 @@ R_PPC_ADDR16_HI
 R_PPC_ADDR16_HA
 R_PPC_RELATIVE
 R_PPC_NONE' |
-	grep -E -v '\<R_PPC64_ADDR64[[:space:]]+mach_' |
-	grep -E -v '\<R_PPC64_ADDR64[[:space:]]+__crc_'
+	([ "$undef_weak_symbols" ] && grep -F -w -v "$undef_weak_symbols" || cat)
 )
 
 if [ -z "$bad_relocs" ]; then
-- 
2.20.1

[PATCH AUTOSEL 5.4 455/459] i40e: Relax i40e_xsk_wakeup's return value when PF is busy

[Sasha Levin]

From: Maciej Fijalkowski <maciej.fijalkowski@intel.com>

[ Upstream commit c77e9f09143822623dd71a0fdc84331129e97c3a ]

Return -EAGAIN instead of -ENETDOWN to provide a slightly milder
information to user space so that an application will know to retry the
syscall when __I40E_CONFIG_BUSY bit is set on pf->state.

Fixes: b3873a5be757 ("net/i40e: Fix concurrency issues between config flow and XSK")
Signed-off-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Björn Töpel <bjorn.topel@intel.com>
Link: https://lore.kernel.org/bpf/20200205045834.56795-2-maciej.fijalkowski@intel.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/net/ethernet/intel/i40e/i40e_xsk.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/intel/i40e/i40e_xsk.c b/drivers/net/ethernet/intel/i40e/i40e_xsk.c
index f73cd917c44f7..3156de786d955 100644
--- a/drivers/net/ethernet/intel/i40e/i40e_xsk.c
+++ b/drivers/net/ethernet/intel/i40e/i40e_xsk.c
@@ -791,7 +791,7 @@ int i40e_xsk_wakeup(struct net_device *dev, u32 queue_id, u32 flags)
 	struct i40e_ring *ring;
 
 	if (test_bit(__I40E_CONFIG_BUSY, pf->state))
-		return -ENETDOWN;
+		return -EAGAIN;
 
 	if (test_bit(__I40E_VSI_DOWN, vsi->state))
 		return -ENETDOWN;
-- 
2.20.1