diff mbox series

[net,2/4] virtio/vsock: Fix sk_error_queue memory leak

Message ID 20241106-vsock-mem-leaks-v1-2-8f4ffc3099e6@rbox.co (mailing list archive)
State Superseded
Delegated to: Netdev Maintainers
Headers show
Series virtio/vsock: Fix memory leaks | expand

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Context Check Description
netdev/series_format success Posting correctly formatted
netdev/tree_selection success Clearly marked for net
netdev/ynl success Generated files up to date; no warnings/errors; no diff in generated;
netdev/fixes_present success Fixes tag present in non-next series
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 3 this patch: 3
netdev/build_tools success No tools touched, skip
netdev/cc_maintainers success CCed 9 of 9 maintainers
netdev/build_clang success Errors and warnings before: 3 this patch: 3
netdev/verify_signedoff success Signed-off-by tag matches author and committer
netdev/deprecated_api success None detected
netdev/check_selftest success No net selftest shell script
netdev/verify_fixes success Fixes tag looks correct
netdev/build_allmodconfig_warn success Errors and warnings before: 4 this patch: 4
netdev/checkpatch success total: 0 errors, 0 warnings, 0 checks, 9 lines checked
netdev/build_clang_rust success No Rust files in patch. Skipping build
netdev/kdoc success Errors and warnings before: 0 this patch: 0
netdev/source_inline success Was 0 now: 0
netdev/contest success net-next-2024-11-07--12-00 (tests: 787)

Commit Message

Michal Luczaj Nov. 6, 2024, 5:51 p.m. UTC
Kernel queues MSG_ZEROCOPY completion notifications on the error queue.
Where they remain, until explicitly recv()ed. To prevent memory leaks,
clean up the queue when the socket is destroyed.

unreferenced object 0xffff8881028beb00 (size 224):
  comm "vsock_test", pid 1218, jiffies 4294694897
  hex dump (first 32 bytes):
    90 b0 21 17 81 88 ff ff 90 b0 21 17 81 88 ff ff  ..!.......!.....
    00 00 00 00 00 00 00 00 00 b0 21 17 81 88 ff ff  ..........!.....
  backtrace (crc 6c7031ca):
    [<ffffffff81418ef7>] kmem_cache_alloc_node_noprof+0x2f7/0x370
    [<ffffffff81d35882>] __alloc_skb+0x132/0x180
    [<ffffffff81d2d32b>] sock_omalloc+0x4b/0x80
    [<ffffffff81d3a8ae>] msg_zerocopy_realloc+0x9e/0x240
    [<ffffffff81fe5cb2>] virtio_transport_send_pkt_info+0x412/0x4c0
    [<ffffffff81fe6183>] virtio_transport_stream_enqueue+0x43/0x50
    [<ffffffff81fe0813>] vsock_connectible_sendmsg+0x373/0x450
    [<ffffffff81d233d5>] ____sys_sendmsg+0x365/0x3a0
    [<ffffffff81d246f4>] ___sys_sendmsg+0x84/0xd0
    [<ffffffff81d26f47>] __sys_sendmsg+0x47/0x80
    [<ffffffff820d3df3>] do_syscall_64+0x93/0x180
    [<ffffffff8220012b>] entry_SYSCALL_64_after_hwframe+0x76/0x7e

Fixes: 581512a6dc93 ("vsock/virtio: MSG_ZEROCOPY flag support")
Signed-off-by: Michal Luczaj <mhal@rbox.co>
---
 net/vmw_vsock/af_vsock.c | 3 +++
 1 file changed, 3 insertions(+)

Comments

Stefano Garzarella Nov. 7, 2024, 10:17 a.m. UTC | #1
On Wed, Nov 06, 2024 at 06:51:19PM +0100, Michal Luczaj wrote:
>Kernel queues MSG_ZEROCOPY completion notifications on the error queue.
>Where they remain, until explicitly recv()ed. To prevent memory leaks,
>clean up the queue when the socket is destroyed.
>
>unreferenced object 0xffff8881028beb00 (size 224):
>  comm "vsock_test", pid 1218, jiffies 4294694897
>  hex dump (first 32 bytes):
>    90 b0 21 17 81 88 ff ff 90 b0 21 17 81 88 ff ff  ..!.......!.....
>    00 00 00 00 00 00 00 00 00 b0 21 17 81 88 ff ff  ..........!.....
>  backtrace (crc 6c7031ca):
>    [<ffffffff81418ef7>] kmem_cache_alloc_node_noprof+0x2f7/0x370
>    [<ffffffff81d35882>] __alloc_skb+0x132/0x180
>    [<ffffffff81d2d32b>] sock_omalloc+0x4b/0x80
>    [<ffffffff81d3a8ae>] msg_zerocopy_realloc+0x9e/0x240
>    [<ffffffff81fe5cb2>] virtio_transport_send_pkt_info+0x412/0x4c0
>    [<ffffffff81fe6183>] virtio_transport_stream_enqueue+0x43/0x50
>    [<ffffffff81fe0813>] vsock_connectible_sendmsg+0x373/0x450
>    [<ffffffff81d233d5>] ____sys_sendmsg+0x365/0x3a0
>    [<ffffffff81d246f4>] ___sys_sendmsg+0x84/0xd0
>    [<ffffffff81d26f47>] __sys_sendmsg+0x47/0x80
>    [<ffffffff820d3df3>] do_syscall_64+0x93/0x180
>    [<ffffffff8220012b>] entry_SYSCALL_64_after_hwframe+0x76/0x7e
>
>Fixes: 581512a6dc93 ("vsock/virtio: MSG_ZEROCOPY flag support")
>Signed-off-by: Michal Luczaj <mhal@rbox.co>
>---
> net/vmw_vsock/af_vsock.c | 3 +++
> 1 file changed, 3 insertions(+)
>
>diff --git a/net/vmw_vsock/af_vsock.c b/net/vmw_vsock/af_vsock.c
>index 35681adedd9aaec3565495158f5342b8aa76c9bc..dfd29160fe11c4675f872c1ee123d65b2da0dae6 100644
>--- a/net/vmw_vsock/af_vsock.c
>+++ b/net/vmw_vsock/af_vsock.c
>@@ -836,6 +836,9 @@ static void vsock_sk_destruct(struct sock *sk)
> {
> 	struct vsock_sock *vsk = vsock_sk(sk);
>
>+	/* Flush MSG_ZEROCOPY leftovers. */
>+	__skb_queue_purge(&sk->sk_error_queue);
>+

It is true that for now this is supported only in the virtio transport, 
but it's more related to the core, so please remove `virtio` from the 
commit title.

The rest LGTM.

Thanks,
Stefano

> 	vsock_deassign_transport(vsk);
>
> 	/* When clearing these addresses, there's no need to set the family and
>
>-- 
>2.46.2
>
Michal Luczaj Nov. 7, 2024, 8:49 p.m. UTC | #2
On 11/7/24 11:17, Stefano Garzarella wrote:
> On Wed, Nov 06, 2024 at 06:51:19PM +0100, Michal Luczaj wrote:
>> Kernel queues MSG_ZEROCOPY completion notifications on the error queue.
>> Where they remain, until explicitly recv()ed. To prevent memory leaks,
>> clean up the queue when the socket is destroyed.
>>
>> unreferenced object 0xffff8881028beb00 (size 224):
>>  comm "vsock_test", pid 1218, jiffies 4294694897
>>  hex dump (first 32 bytes):
>>    90 b0 21 17 81 88 ff ff 90 b0 21 17 81 88 ff ff  ..!.......!.....
>>    00 00 00 00 00 00 00 00 00 b0 21 17 81 88 ff ff  ..........!.....
>>  backtrace (crc 6c7031ca):
>>    [<ffffffff81418ef7>] kmem_cache_alloc_node_noprof+0x2f7/0x370
>>    [<ffffffff81d35882>] __alloc_skb+0x132/0x180
>>    [<ffffffff81d2d32b>] sock_omalloc+0x4b/0x80
>>    [<ffffffff81d3a8ae>] msg_zerocopy_realloc+0x9e/0x240
>>    [<ffffffff81fe5cb2>] virtio_transport_send_pkt_info+0x412/0x4c0
>>    [<ffffffff81fe6183>] virtio_transport_stream_enqueue+0x43/0x50
>>    [<ffffffff81fe0813>] vsock_connectible_sendmsg+0x373/0x450
>>    [<ffffffff81d233d5>] ____sys_sendmsg+0x365/0x3a0
>>    [<ffffffff81d246f4>] ___sys_sendmsg+0x84/0xd0
>>    [<ffffffff81d26f47>] __sys_sendmsg+0x47/0x80
>>    [<ffffffff820d3df3>] do_syscall_64+0x93/0x180
>>    [<ffffffff8220012b>] entry_SYSCALL_64_after_hwframe+0x76/0x7e
>>
>> Fixes: 581512a6dc93 ("vsock/virtio: MSG_ZEROCOPY flag support")
>> Signed-off-by: Michal Luczaj <mhal@rbox.co>
>> ---
>> net/vmw_vsock/af_vsock.c | 3 +++
>> 1 file changed, 3 insertions(+)
>>
>> diff --git a/net/vmw_vsock/af_vsock.c b/net/vmw_vsock/af_vsock.c
>> index 35681adedd9aaec3565495158f5342b8aa76c9bc..dfd29160fe11c4675f872c1ee123d65b2da0dae6 100644
>> --- a/net/vmw_vsock/af_vsock.c
>> +++ b/net/vmw_vsock/af_vsock.c
>> @@ -836,6 +836,9 @@ static void vsock_sk_destruct(struct sock *sk)
>> {
>> 	struct vsock_sock *vsk = vsock_sk(sk);
>>
>> +	/* Flush MSG_ZEROCOPY leftovers. */
>> +	__skb_queue_purge(&sk->sk_error_queue);
>> +
> 
> It is true that for now this is supported only in the virtio transport, 
> but it's more related to the core, so please remove `virtio` from the 
> commit title.
> 
> The rest LGTM.
> ...

OK, done. Here's v2 of the series:
https://lore.kernel.org/netdev/20241107-vsock-mem-leaks-v2-0-4e21bfcfc818@rbox.co/

Thanks for the reviews,
Michal
diff mbox series

Patch

diff --git a/net/vmw_vsock/af_vsock.c b/net/vmw_vsock/af_vsock.c
index 35681adedd9aaec3565495158f5342b8aa76c9bc..dfd29160fe11c4675f872c1ee123d65b2da0dae6 100644
--- a/net/vmw_vsock/af_vsock.c
+++ b/net/vmw_vsock/af_vsock.c
@@ -836,6 +836,9 @@  static void vsock_sk_destruct(struct sock *sk)
 {
 	struct vsock_sock *vsk = vsock_sk(sk);
 
+	/* Flush MSG_ZEROCOPY leftovers. */
+	__skb_queue_purge(&sk->sk_error_queue);
+
 	vsock_deassign_transport(vsk);
 
 	/* When clearing these addresses, there's no need to set the family and