diff mbox series

[bpf,sockmap,2/2] bpf, sockmap: sk_prot needs inuse_idx set for proc stats

Message ID 20210630215349.73263-3-john.fastabend@gmail.com
State New
Headers show
Series potential memleak and proc stats fix | expand

Commit Message

John Fastabend June 30, 2021, 9:53 p.m. UTC 
Proc socket stats use sk_prot->inuse_idx value to record inuse sock stats.
We currently do not set this correctly from sockmap side. The result is
reading sock stats '/proc/net/sockstat' gives incorrect values. The
socket counter is incremented correctly, but because we don't set the
counter correctly when we replace sk_prot we may omit the decrement.

Fixes: 604326b41a6fb ("bpf, sockmap: convert to generic sk_msg interface")
Signed-off-by: John Fastabend <john.fastabend@gmail.com>
---
 net/core/sock_map.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

Comments

kernel test robot July 1, 2021, 6:58 a.m. UTC | #1 
Hi John,

I love your patch! Yet something to improve:

[auto build test ERROR on linus/master]
[also build test ERROR on v5.13 next-20210630]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch]

url:    https://github.com/0day-ci/linux/commits/John-Fastabend/potential-memleak-and-proc-stats-fix/20210701-055546
base:   https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git 440462198d9c45e48f2d8d9b18c5702d92282f46
config: sparc-buildonly-randconfig-r006-20210701 (attached as .config)
compiler: sparc64-linux-gcc (GCC) 9.3.0
reproduce (this is a W=1 build):
        wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # https://github.com/0day-ci/linux/commit/82ee893f50c6899cb557f22d0ae9a657b14d183f
        git remote add linux-review https://github.com/0day-ci/linux
        git fetch --no-tags linux-review John-Fastabend/potential-memleak-and-proc-stats-fix/20210701-055546
        git checkout 82ee893f50c6899cb557f22d0ae9a657b14d183f
        # save the attached .config to linux build tree
        mkdir build_dir
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-9.3.0 make.cross O=build_dir ARCH=sparc SHELL=/bin/bash net/core/

If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@intel.com>

All errors (new ones prefixed by >>):

   net/core/sock_map.c: In function 'sock_map_link':
>> net/core/sock_map.c:296:19: error: 'struct proto' has no member named 'inuse_idx'

     296 |  idx = sk->sk_prot->inuse_idx;
         |                   ^~
   net/core/sock_map.c:300:13: error: 'struct proto' has no member named 'inuse_idx'
     300 |  sk->sk_prot->inuse_idx = idx;
         |             ^~


vim +296 net/core/sock_map.c

   215	
   216	static int sock_map_link(struct bpf_map *map, struct sock *sk)
   217	{
   218		struct sk_psock_progs *progs = sock_map_progs(map);
   219		struct bpf_prog *stream_verdict = NULL;
   220		struct bpf_prog *stream_parser = NULL;
   221		struct bpf_prog *skb_verdict = NULL;
   222		struct bpf_prog *msg_parser = NULL;
   223		struct sk_psock *psock;
   224		int ret, idx;
   225	
   226		/* Only sockets we can redirect into/from in BPF need to hold
   227		 * refs to parser/verdict progs and have their sk_data_ready
   228		 * and sk_write_space callbacks overridden.
   229		 */
   230		if (!sock_map_redirect_allowed(sk))
   231			goto no_progs;
   232	
   233		stream_verdict = READ_ONCE(progs->stream_verdict);
   234		if (stream_verdict) {
   235			stream_verdict = bpf_prog_inc_not_zero(stream_verdict);
   236			if (IS_ERR(stream_verdict))
   237				return PTR_ERR(stream_verdict);
   238		}
   239	
   240		stream_parser = READ_ONCE(progs->stream_parser);
   241		if (stream_parser) {
   242			stream_parser = bpf_prog_inc_not_zero(stream_parser);
   243			if (IS_ERR(stream_parser)) {
   244				ret = PTR_ERR(stream_parser);
   245				goto out_put_stream_verdict;
   246			}
   247		}
   248	
   249		msg_parser = READ_ONCE(progs->msg_parser);
   250		if (msg_parser) {
   251			msg_parser = bpf_prog_inc_not_zero(msg_parser);
   252			if (IS_ERR(msg_parser)) {
   253				ret = PTR_ERR(msg_parser);
   254				goto out_put_stream_parser;
   255			}
   256		}
   257	
   258		skb_verdict = READ_ONCE(progs->skb_verdict);
   259		if (skb_verdict) {
   260			skb_verdict = bpf_prog_inc_not_zero(skb_verdict);
   261			if (IS_ERR(skb_verdict)) {
   262				ret = PTR_ERR(skb_verdict);
   263				goto out_put_msg_parser;
   264			}
   265		}
   266	
   267	no_progs:
   268		psock = sock_map_psock_get_checked(sk);
   269		if (IS_ERR(psock)) {
   270			ret = PTR_ERR(psock);
   271			goto out_progs;
   272		}
   273	
   274		if (psock) {
   275			if ((msg_parser && READ_ONCE(psock->progs.msg_parser)) ||
   276			    (stream_parser  && READ_ONCE(psock->progs.stream_parser)) ||
   277			    (skb_verdict && READ_ONCE(psock->progs.skb_verdict)) ||
   278			    (skb_verdict && READ_ONCE(psock->progs.stream_verdict)) ||
   279			    (stream_verdict && READ_ONCE(psock->progs.skb_verdict)) ||
   280			    (stream_verdict && READ_ONCE(psock->progs.stream_verdict))) {
   281				sk_psock_put(sk, psock);
   282				ret = -EBUSY;
   283				goto out_progs;
   284			}
   285		} else {
   286			psock = sk_psock_init(sk, map->numa_node);
   287			if (IS_ERR(psock)) {
   288				ret = PTR_ERR(psock);
   289				goto out_progs;
   290			}
   291		}
   292	
   293		if (msg_parser)
   294			psock_set_prog(&psock->progs.msg_parser, msg_parser);
   295	
 > 296		idx = sk->sk_prot->inuse_idx;

   297		ret = sock_map_init_proto(sk, psock);
   298		if (ret < 0)
   299			goto out_drop;
   300		sk->sk_prot->inuse_idx = idx;
   301	
   302		write_lock_bh(&sk->sk_callback_lock);
   303		if (stream_parser && stream_verdict && !psock->saved_data_ready) {
   304			ret = sk_psock_init_strp(sk, psock);
   305			if (ret)
   306				goto out_unlock_drop;
   307			psock_set_prog(&psock->progs.stream_verdict, stream_verdict);
   308			psock_set_prog(&psock->progs.stream_parser, stream_parser);
   309			sk_psock_start_strp(sk, psock);
   310		} else if (!stream_parser && stream_verdict && !psock->saved_data_ready) {
   311			psock_set_prog(&psock->progs.stream_verdict, stream_verdict);
   312			sk_psock_start_verdict(sk,psock);
   313		} else if (!stream_verdict && skb_verdict && !psock->saved_data_ready) {
   314			psock_set_prog(&psock->progs.skb_verdict, skb_verdict);
   315			sk_psock_start_verdict(sk, psock);
   316		}
   317		write_unlock_bh(&sk->sk_callback_lock);
   318		return 0;
   319	out_unlock_drop:
   320		write_unlock_bh(&sk->sk_callback_lock);
   321	out_drop:
   322		sk_psock_put(sk, psock);
   323	out_progs:
   324		if (skb_verdict)
   325			bpf_prog_put(skb_verdict);
   326	out_put_msg_parser:
   327		if (msg_parser)
   328			bpf_prog_put(msg_parser);
   329	out_put_stream_parser:
   330		if (stream_parser)
   331			bpf_prog_put(stream_parser);
   332	out_put_stream_verdict:
   333		if (stream_verdict)
   334			bpf_prog_put(stream_verdict);
   335		return ret;
   336	}
   337	

---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org
kernel test robot July 1, 2021, 8:21 a.m. UTC | #2 
Hi John,

I love your patch! Yet something to improve:

[auto build test ERROR on linus/master]
[also build test ERROR on v5.13 next-20210630]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch]

url:    https://github.com/0day-ci/linux/commits/John-Fastabend/potential-memleak-and-proc-stats-fix/20210701-055546
base:   https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git 440462198d9c45e48f2d8d9b18c5702d92282f46
config: arm64-randconfig-r026-20210630 (attached as .config)
compiler: clang version 13.0.0 (https://github.com/llvm/llvm-project e7e71e9454ed76c1b3d8140170b5333c28bef1be)
reproduce (this is a W=1 build):
        wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # install arm64 cross compiling tool for clang build
        # apt-get install binutils-aarch64-linux-gnu
        # https://github.com/0day-ci/linux/commit/82ee893f50c6899cb557f22d0ae9a657b14d183f
        git remote add linux-review https://github.com/0day-ci/linux
        git fetch --no-tags linux-review John-Fastabend/potential-memleak-and-proc-stats-fix/20210701-055546
        git checkout 82ee893f50c6899cb557f22d0ae9a657b14d183f
        # save the attached .config to linux build tree
        mkdir build_dir
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross O=build_dir ARCH=arm64 SHELL=/bin/bash arch/arm64/ net/

If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@intel.com>

All errors (new ones prefixed by >>):

>> net/core/sock_map.c:296:21: error: no member named 'inuse_idx' in 'struct proto'

           idx = sk->sk_prot->inuse_idx;
                 ~~~~~~~~~~~  ^
   net/core/sock_map.c:300:15: error: no member named 'inuse_idx' in 'struct proto'
           sk->sk_prot->inuse_idx = idx;
           ~~~~~~~~~~~  ^
   2 errors generated.


vim +296 net/core/sock_map.c

   215	
   216	static int sock_map_link(struct bpf_map *map, struct sock *sk)
   217	{
   218		struct sk_psock_progs *progs = sock_map_progs(map);
   219		struct bpf_prog *stream_verdict = NULL;
   220		struct bpf_prog *stream_parser = NULL;
   221		struct bpf_prog *skb_verdict = NULL;
   222		struct bpf_prog *msg_parser = NULL;
   223		struct sk_psock *psock;
   224		int ret, idx;
   225	
   226		/* Only sockets we can redirect into/from in BPF need to hold
   227		 * refs to parser/verdict progs and have their sk_data_ready
   228		 * and sk_write_space callbacks overridden.
   229		 */
   230		if (!sock_map_redirect_allowed(sk))
   231			goto no_progs;
   232	
   233		stream_verdict = READ_ONCE(progs->stream_verdict);
   234		if (stream_verdict) {
   235			stream_verdict = bpf_prog_inc_not_zero(stream_verdict);
   236			if (IS_ERR(stream_verdict))
   237				return PTR_ERR(stream_verdict);
   238		}
   239	
   240		stream_parser = READ_ONCE(progs->stream_parser);
   241		if (stream_parser) {
   242			stream_parser = bpf_prog_inc_not_zero(stream_parser);
   243			if (IS_ERR(stream_parser)) {
   244				ret = PTR_ERR(stream_parser);
   245				goto out_put_stream_verdict;
   246			}
   247		}
   248	
   249		msg_parser = READ_ONCE(progs->msg_parser);
   250		if (msg_parser) {
   251			msg_parser = bpf_prog_inc_not_zero(msg_parser);
   252			if (IS_ERR(msg_parser)) {
   253				ret = PTR_ERR(msg_parser);
   254				goto out_put_stream_parser;
   255			}
   256		}
   257	
   258		skb_verdict = READ_ONCE(progs->skb_verdict);
   259		if (skb_verdict) {
   260			skb_verdict = bpf_prog_inc_not_zero(skb_verdict);
   261			if (IS_ERR(skb_verdict)) {
   262				ret = PTR_ERR(skb_verdict);
   263				goto out_put_msg_parser;
   264			}
   265		}
   266	
   267	no_progs:
   268		psock = sock_map_psock_get_checked(sk);
   269		if (IS_ERR(psock)) {
   270			ret = PTR_ERR(psock);
   271			goto out_progs;
   272		}
   273	
   274		if (psock) {
   275			if ((msg_parser && READ_ONCE(psock->progs.msg_parser)) ||
   276			    (stream_parser  && READ_ONCE(psock->progs.stream_parser)) ||
   277			    (skb_verdict && READ_ONCE(psock->progs.skb_verdict)) ||
   278			    (skb_verdict && READ_ONCE(psock->progs.stream_verdict)) ||
   279			    (stream_verdict && READ_ONCE(psock->progs.skb_verdict)) ||
   280			    (stream_verdict && READ_ONCE(psock->progs.stream_verdict))) {
   281				sk_psock_put(sk, psock);
   282				ret = -EBUSY;
   283				goto out_progs;
   284			}
   285		} else {
   286			psock = sk_psock_init(sk, map->numa_node);
   287			if (IS_ERR(psock)) {
   288				ret = PTR_ERR(psock);
   289				goto out_progs;
   290			}
   291		}
   292	
   293		if (msg_parser)
   294			psock_set_prog(&psock->progs.msg_parser, msg_parser);
   295	
 > 296		idx = sk->sk_prot->inuse_idx;

   297		ret = sock_map_init_proto(sk, psock);
   298		if (ret < 0)
   299			goto out_drop;
   300		sk->sk_prot->inuse_idx = idx;
   301	
   302		write_lock_bh(&sk->sk_callback_lock);
   303		if (stream_parser && stream_verdict && !psock->saved_data_ready) {
   304			ret = sk_psock_init_strp(sk, psock);
   305			if (ret)
   306				goto out_unlock_drop;
   307			psock_set_prog(&psock->progs.stream_verdict, stream_verdict);
   308			psock_set_prog(&psock->progs.stream_parser, stream_parser);
   309			sk_psock_start_strp(sk, psock);
   310		} else if (!stream_parser && stream_verdict && !psock->saved_data_ready) {
   311			psock_set_prog(&psock->progs.stream_verdict, stream_verdict);
   312			sk_psock_start_verdict(sk,psock);
   313		} else if (!stream_verdict && skb_verdict && !psock->saved_data_ready) {
   314			psock_set_prog(&psock->progs.skb_verdict, skb_verdict);
   315			sk_psock_start_verdict(sk, psock);
   316		}
   317		write_unlock_bh(&sk->sk_callback_lock);
   318		return 0;
   319	out_unlock_drop:
   320		write_unlock_bh(&sk->sk_callback_lock);
   321	out_drop:
   322		sk_psock_put(sk, psock);
   323	out_progs:
   324		if (skb_verdict)
   325			bpf_prog_put(skb_verdict);
   326	out_put_msg_parser:
   327		if (msg_parser)
   328			bpf_prog_put(msg_parser);
   329	out_put_stream_parser:
   330		if (stream_parser)
   331			bpf_prog_put(stream_parser);
   332	out_put_stream_verdict:
   333		if (stream_verdict)
   334			bpf_prog_put(stream_verdict);
   335		return ret;
   336	}
   337	

---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org
diff mbox series

Patch

diff --git a/net/core/sock_map.c b/net/core/sock_map.c
index 60decd6420ca..29e7bae65db5 100644
--- a/net/core/sock_map.c
+++ b/net/core/sock_map.c
@@ -221,7 +221,7 @@  static int sock_map_link(struct bpf_map *map, struct sock *sk)
 	struct bpf_prog *skb_verdict = NULL;
 	struct bpf_prog *msg_parser = NULL;
 	struct sk_psock *psock;
-	int ret;
+	int ret, idx;
 
 	/* Only sockets we can redirect into/from in BPF need to hold
 	 * refs to parser/verdict progs and have their sk_data_ready
@@ -293,9 +293,11 @@  static int sock_map_link(struct bpf_map *map, struct sock *sk)
 	if (msg_parser)
 		psock_set_prog(&psock->progs.msg_parser, msg_parser);

+	idx = sk->sk_prot->inuse_idx;
 	ret = sock_map_init_proto(sk, psock);
 	if (ret < 0)
 		goto out_drop;
+	sk->sk_prot->inuse_idx = idx;
 
 	write_lock_bh(&sk->sk_callback_lock);
 	if (stream_parser && stream_verdict && !psock->saved_data_ready) {