diff mbox series

[bpf] bpf, sockmap: fix an infinite loop error when len is 0 in tcp_bpf_recvmsg_parser()

Message ID 20230223120212.1604148-1-liujian56@huawei.com (mailing list archive)
State Superseded
Delegated to: BPF
Headers show
Series [bpf] bpf, sockmap: fix an infinite loop error when len is 0 in tcp_bpf_recvmsg_parser() | expand

Checks

Context Check Description
netdev/tree_selection success Clearly marked for bpf
netdev/fixes_present success Fixes tag present in non-next series
netdev/subject_prefix success Link
netdev/cover_letter success Single patches do not need cover letters
netdev/patch_count success Link
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 2 this patch: 2
netdev/cc_maintainers success CCed 12 of 12 maintainers
netdev/build_clang success Errors and warnings before: 0 this patch: 0
netdev/module_param success Was 0 now: 0
netdev/verify_signedoff success Signed-off-by tag matches author and committer
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: 2 this patch: 2
netdev/checkpatch success total: 0 errors, 0 warnings, 0 checks, 36 lines checked
netdev/kdoc success Errors and warnings before: 0 this patch: 0
netdev/source_inline success Was 0 now: 0
bpf/vmtest-bpf-PR success PR summary
bpf/vmtest-bpf-VM_Test-1 success Logs for ShellCheck
bpf/vmtest-bpf-VM_Test-2 success Logs for build for aarch64 with gcc
bpf/vmtest-bpf-VM_Test-3 success Logs for build for aarch64 with llvm-17
bpf/vmtest-bpf-VM_Test-5 success Logs for build for x86_64 with gcc
bpf/vmtest-bpf-VM_Test-6 success Logs for build for x86_64 with llvm-17
bpf/vmtest-bpf-VM_Test-7 success Logs for llvm-toolchain
bpf/vmtest-bpf-VM_Test-8 success Logs for set-matrix
bpf/vmtest-bpf-VM_Test-4 success Logs for build for s390x with gcc
bpf/vmtest-bpf-VM_Test-9 success Logs for test_maps on aarch64 with gcc
bpf/vmtest-bpf-VM_Test-10 success Logs for test_maps on aarch64 with llvm-17
bpf/vmtest-bpf-VM_Test-12 success Logs for test_maps on x86_64 with gcc
bpf/vmtest-bpf-VM_Test-13 success Logs for test_maps on x86_64 with llvm-17
bpf/vmtest-bpf-VM_Test-14 fail Logs for test_progs on aarch64 with gcc
bpf/vmtest-bpf-VM_Test-17 fail Logs for test_progs on x86_64 with gcc
bpf/vmtest-bpf-VM_Test-18 fail Logs for test_progs on x86_64 with llvm-17
bpf/vmtest-bpf-VM_Test-19 fail Logs for test_progs_no_alu32 on aarch64 with gcc
bpf/vmtest-bpf-VM_Test-20 fail Logs for test_progs_no_alu32 on aarch64 with llvm-17
bpf/vmtest-bpf-VM_Test-22 fail Logs for test_progs_no_alu32 on x86_64 with gcc
bpf/vmtest-bpf-VM_Test-23 fail Logs for test_progs_no_alu32 on x86_64 with llvm-17
bpf/vmtest-bpf-VM_Test-24 success Logs for test_progs_no_alu32_parallel on aarch64 with gcc
bpf/vmtest-bpf-VM_Test-25 success Logs for test_progs_no_alu32_parallel on aarch64 with llvm-17
bpf/vmtest-bpf-VM_Test-27 success Logs for test_progs_no_alu32_parallel on x86_64 with gcc
bpf/vmtest-bpf-VM_Test-28 success Logs for test_progs_no_alu32_parallel on x86_64 with llvm-17
bpf/vmtest-bpf-VM_Test-29 success Logs for test_progs_parallel on aarch64 with gcc
bpf/vmtest-bpf-VM_Test-30 success Logs for test_progs_parallel on aarch64 with llvm-17
bpf/vmtest-bpf-VM_Test-32 success Logs for test_progs_parallel on x86_64 with gcc
bpf/vmtest-bpf-VM_Test-33 success Logs for test_progs_parallel on x86_64 with llvm-17
bpf/vmtest-bpf-VM_Test-34 success Logs for test_verifier on aarch64 with gcc
bpf/vmtest-bpf-VM_Test-35 success Logs for test_verifier on aarch64 with llvm-17
bpf/vmtest-bpf-VM_Test-37 success Logs for test_verifier on x86_64 with gcc
bpf/vmtest-bpf-VM_Test-38 success Logs for test_verifier on x86_64 with llvm-17
bpf/vmtest-bpf-VM_Test-15 fail Logs for test_progs on aarch64 with llvm-17
bpf/vmtest-bpf-VM_Test-21 fail Logs for test_progs_no_alu32 on s390x with gcc
bpf/vmtest-bpf-VM_Test-36 success Logs for test_verifier on s390x with gcc
bpf/vmtest-bpf-VM_Test-16 fail Logs for test_progs on s390x with gcc
bpf/vmtest-bpf-VM_Test-31 success Logs for test_progs_parallel on s390x with gcc
bpf/vmtest-bpf-VM_Test-11 success Logs for test_maps on s390x with gcc
bpf/vmtest-bpf-VM_Test-26 success Logs for test_progs_no_alu32_parallel on s390x with gcc

Commit Message

liujian (CE) Feb. 23, 2023, 12:02 p.m. UTC 
When the buffer length of the recvmsg system call is 0, we got the
flollowing soft lockup problem:

watchdog: BUG: soft lockup - CPU#3 stuck for 27s! [a.out:6149]
CPU: 3 PID: 6149 Comm: a.out Kdump: loaded Not tainted 6.2.0+ #30
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.15.0-1 04/01/2014
RIP: 0010:remove_wait_queue+0xb/0xc0
Code: 5e 41 5f c3 cc cc cc cc 0f 1f 80 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 0f 1f 44 00 00 41 57 <41> 56 41 55 41 54 55 48 89 fd 53 48 89 f3 4c 8d 6b 18 4c 8d 73 20
RSP: 0018:ffff88811b5978b8 EFLAGS: 00000246
RAX: 0000000000000000 RBX: ffff88811a7d3780 RCX: ffffffffb7a4d768
RDX: dffffc0000000000 RSI: ffff88811b597908 RDI: ffff888115408040
RBP: 1ffff110236b2f1b R08: 0000000000000000 R09: ffff88811a7d37e7
R10: ffffed10234fa6fc R11: 0000000000000001 R12: ffff88811179b800
R13: 0000000000000001 R14: ffff88811a7d38a8 R15: ffff88811a7d37e0
FS:  00007f6fb5398740(0000) GS:ffff888237180000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000020000000 CR3: 000000010b6ba002 CR4: 0000000000370ee0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 tcp_msg_wait_data+0x279/0x2f0
 tcp_bpf_recvmsg_parser+0x3c6/0x490
 inet_recvmsg+0x280/0x290
 sock_recvmsg+0xfc/0x120
 ____sys_recvmsg+0x160/0x3d0
 ___sys_recvmsg+0xf0/0x180
 __sys_recvmsg+0xea/0x1a0
 do_syscall_64+0x3f/0x90
 entry_SYSCALL_64_after_hwframe+0x72/0xdc

The logic in tcp_bpf_recvmsg_parser is as follows:

msg_bytes_ready:
	copied = sk_msg_recvmsg(sk, psock, msg, len, flags);
	if (!copied) {
		wait data;
		goto msg_bytes_ready;
	}

In this case, "copied" alway is 0, the infinite loop occurs.

According to the Linux system call man page, 0 should be returned in this
case. Therefore, in tcp_bpf_recvmsg_parser(), if the length is 0, directly
return.

Also modify several other functions with the same problem.

Fixes: 1f5be6b3b063 ("udp: Implement udp_bpf_recvmsg() for sockmap")
Fixes: 9825d866ce0d ("af_unix: Implement unix_dgram_bpf_recvmsg()")
Fixes: c5d2177a72a1 ("bpf, sockmap: Fix race in ingress receive verdict with redirect to self")
Fixes: 604326b41a6f ("bpf, sockmap: convert to generic sk_msg interface")
Signed-off-by: Liu Jian <liujian56@huawei.com>
---
 net/ipv4/tcp_bpf.c  | 6 ++++++
 net/ipv4/udp_bpf.c  | 3 +++
 net/unix/unix_bpf.c | 3 +++
 3 files changed, 12 insertions(+)

Comments

John Fastabend Feb. 28, 2023, 8:36 a.m. UTC | #1 
Liu Jian wrote:
> When the buffer length of the recvmsg system call is 0, we got the
> flollowing soft lockup problem:
> 
> watchdog: BUG: soft lockup - CPU#3 stuck for 27s! [a.out:6149]
> CPU: 3 PID: 6149 Comm: a.out Kdump: loaded Not tainted 6.2.0+ #30
> Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.15.0-1 04/01/2014
> RIP: 0010:remove_wait_queue+0xb/0xc0
> Code: 5e 41 5f c3 cc cc cc cc 0f 1f 80 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 0f 1f 44 00 00 41 57 <41> 56 41 55 41 54 55 48 89 fd 53 48 89 f3 4c 8d 6b 18 4c 8d 73 20
> RSP: 0018:ffff88811b5978b8 EFLAGS: 00000246
> RAX: 0000000000000000 RBX: ffff88811a7d3780 RCX: ffffffffb7a4d768
> RDX: dffffc0000000000 RSI: ffff88811b597908 RDI: ffff888115408040
> RBP: 1ffff110236b2f1b R08: 0000000000000000 R09: ffff88811a7d37e7
> R10: ffffed10234fa6fc R11: 0000000000000001 R12: ffff88811179b800
> R13: 0000000000000001 R14: ffff88811a7d38a8 R15: ffff88811a7d37e0
> FS:  00007f6fb5398740(0000) GS:ffff888237180000(0000) knlGS:0000000000000000
> CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
> CR2: 0000000020000000 CR3: 000000010b6ba002 CR4: 0000000000370ee0
> DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
> DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
> Call Trace:
>  <TASK>
>  tcp_msg_wait_data+0x279/0x2f0
>  tcp_bpf_recvmsg_parser+0x3c6/0x490
>  inet_recvmsg+0x280/0x290
>  sock_recvmsg+0xfc/0x120
>  ____sys_recvmsg+0x160/0x3d0
>  ___sys_recvmsg+0xf0/0x180
>  __sys_recvmsg+0xea/0x1a0
>  do_syscall_64+0x3f/0x90
>  entry_SYSCALL_64_after_hwframe+0x72/0xdc
> 
> The logic in tcp_bpf_recvmsg_parser is as follows:
> 
> msg_bytes_ready:
> 	copied = sk_msg_recvmsg(sk, psock, msg, len, flags);
> 	if (!copied) {
> 		wait data;
> 		goto msg_bytes_ready;
> 	}
> 
> In this case, "copied" alway is 0, the infinite loop occurs.
> 
> According to the Linux system call man page, 0 should be returned in this
> case. Therefore, in tcp_bpf_recvmsg_parser(), if the length is 0, directly
> return.
> 
> Also modify several other functions with the same problem.
> 
> Fixes: 1f5be6b3b063 ("udp: Implement udp_bpf_recvmsg() for sockmap")
> Fixes: 9825d866ce0d ("af_unix: Implement unix_dgram_bpf_recvmsg()")
> Fixes: c5d2177a72a1 ("bpf, sockmap: Fix race in ingress receive verdict with redirect to self")
> Fixes: 604326b41a6f ("bpf, sockmap: convert to generic sk_msg interface")
> Signed-off-by: Liu Jian <liujian56@huawei.com>
> ---

Thanks.

Acked-by: John Fastabend <john.fastabend@gmail.com>
Alexei Starovoitov March 3, 2023, 7:03 a.m. UTC | #2 
On Tue, Feb 28, 2023 at 12:36 AM John Fastabend
<john.fastabend@gmail.com> wrote:
>
> Liu Jian wrote:
> > When the buffer length of the recvmsg system call is 0, we got the
> > flollowing soft lockup problem:
> >
> > watchdog: BUG: soft lockup - CPU#3 stuck for 27s! [a.out:6149]
> > CPU: 3 PID: 6149 Comm: a.out Kdump: loaded Not tainted 6.2.0+ #30
> > Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.15.0-1 04/01/2014
> > RIP: 0010:remove_wait_queue+0xb/0xc0
> > Code: 5e 41 5f c3 cc cc cc cc 0f 1f 80 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 0f 1f 44 00 00 41 57 <41> 56 41 55 41 54 55 48 89 fd 53 48 89 f3 4c 8d 6b 18 4c 8d 73 20
> > RSP: 0018:ffff88811b5978b8 EFLAGS: 00000246
> > RAX: 0000000000000000 RBX: ffff88811a7d3780 RCX: ffffffffb7a4d768
> > RDX: dffffc0000000000 RSI: ffff88811b597908 RDI: ffff888115408040
> > RBP: 1ffff110236b2f1b R08: 0000000000000000 R09: ffff88811a7d37e7
> > R10: ffffed10234fa6fc R11: 0000000000000001 R12: ffff88811179b800
> > R13: 0000000000000001 R14: ffff88811a7d38a8 R15: ffff88811a7d37e0
> > FS:  00007f6fb5398740(0000) GS:ffff888237180000(0000) knlGS:0000000000000000
> > CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
> > CR2: 0000000020000000 CR3: 000000010b6ba002 CR4: 0000000000370ee0
> > DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
> > DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
> > Call Trace:
> >  <TASK>
> >  tcp_msg_wait_data+0x279/0x2f0
> >  tcp_bpf_recvmsg_parser+0x3c6/0x490
> >  inet_recvmsg+0x280/0x290
> >  sock_recvmsg+0xfc/0x120
> >  ____sys_recvmsg+0x160/0x3d0
> >  ___sys_recvmsg+0xf0/0x180
> >  __sys_recvmsg+0xea/0x1a0
> >  do_syscall_64+0x3f/0x90
> >  entry_SYSCALL_64_after_hwframe+0x72/0xdc
> >
> > The logic in tcp_bpf_recvmsg_parser is as follows:
> >
> > msg_bytes_ready:
> >       copied = sk_msg_recvmsg(sk, psock, msg, len, flags);
> >       if (!copied) {
> >               wait data;
> >               goto msg_bytes_ready;
> >       }
> >
> > In this case, "copied" alway is 0, the infinite loop occurs.
> >
> > According to the Linux system call man page, 0 should be returned in this
> > case. Therefore, in tcp_bpf_recvmsg_parser(), if the length is 0, directly
> > return.
> >
> > Also modify several other functions with the same problem.
> >
> > Fixes: 1f5be6b3b063 ("udp: Implement udp_bpf_recvmsg() for sockmap")
> > Fixes: 9825d866ce0d ("af_unix: Implement unix_dgram_bpf_recvmsg()")
> > Fixes: c5d2177a72a1 ("bpf, sockmap: Fix race in ingress receive verdict with redirect to self")
> > Fixes: 604326b41a6f ("bpf, sockmap: convert to generic sk_msg interface")
> > Signed-off-by: Liu Jian <liujian56@huawei.com>
> > ---
>
> Thanks.
>
> Acked-by: John Fastabend <john.fastabend@gmail.com>

Thanks John.

Liu,

could you please change if (len == 0) to if (!len) and respin with John's ack.
Thanks
liujian (CE) March 3, 2023, 7:49 a.m. UTC | #3 
> -----Original Message-----
> From: Alexei Starovoitov [mailto:alexei.starovoitov@gmail.com]
> Sent: Friday, March 3, 2023 3:04 PM
> To: John Fastabend <john.fastabend@gmail.com>
> Cc: liujian (CE) <liujian56@huawei.com>; Eric Dumazet
> <edumazet@google.com>; Jakub Sitnicki <jakub@cloudflare.com>; David S.
> Miller <davem@davemloft.net>; David Ahern <dsahern@kernel.org>; Jakub
> Kicinski <kuba@kernel.org>; Paolo Abeni <pabeni@redhat.com>; Alexei
> Starovoitov <ast@kernel.org>; Cong Wang <cong.wang@bytedance.com>;
> Daniel Borkmann <daniel@iogearbox.net>; Network Development
> <netdev@vger.kernel.org>; bpf <bpf@vger.kernel.org>
> Subject: Re: [PATCH bpf] bpf, sockmap: fix an infinite loop error when len is 0
> in tcp_bpf_recvmsg_parser()
> 
> On Tue, Feb 28, 2023 at 12:36 AM John Fastabend
> <john.fastabend@gmail.com> wrote:
> >
> > Liu Jian wrote:
> > > When the buffer length of the recvmsg system call is 0, we got the
> > > flollowing soft lockup problem:
> > >
> > > watchdog: BUG: soft lockup - CPU#3 stuck for 27s! [a.out:6149]
> > > CPU: 3 PID: 6149 Comm: a.out Kdump: loaded Not tainted 6.2.0+ #30
> > > Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.15.0-1
> > > 04/01/2014
> > > RIP: 0010:remove_wait_queue+0xb/0xc0
> > > Code: 5e 41 5f c3 cc cc cc cc 0f 1f 80 00 00 00 00 90 90 90 90 90 90
> > > 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 0f 1f 44 00 00 41 57 <41>
> > > 56 41 55 41 54 55 48 89 fd 53 48 89 f3 4c 8d 6b 18 4c 8d 73 20
> > > RSP: 0018:ffff88811b5978b8 EFLAGS: 00000246
> > > RAX: 0000000000000000 RBX: ffff88811a7d3780 RCX: ffffffffb7a4d768
> > > RDX: dffffc0000000000 RSI: ffff88811b597908 RDI: ffff888115408040
> > > RBP: 1ffff110236b2f1b R08: 0000000000000000 R09: ffff88811a7d37e7
> > > R10: ffffed10234fa6fc R11: 0000000000000001 R12: ffff88811179b800
> > > R13: 0000000000000001 R14: ffff88811a7d38a8 R15: ffff88811a7d37e0
> > > FS:  00007f6fb5398740(0000) GS:ffff888237180000(0000)
> > > knlGS:0000000000000000
> > > CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
> > > CR2: 0000000020000000 CR3: 000000010b6ba002 CR4: 0000000000370ee0
> > > DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
> > > DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
> > > Call Trace:
> > >  <TASK>
> > >  tcp_msg_wait_data+0x279/0x2f0
> > >  tcp_bpf_recvmsg_parser+0x3c6/0x490
> > >  inet_recvmsg+0x280/0x290
> > >  sock_recvmsg+0xfc/0x120
> > >  ____sys_recvmsg+0x160/0x3d0
> > >  ___sys_recvmsg+0xf0/0x180
> > >  __sys_recvmsg+0xea/0x1a0
> > >  do_syscall_64+0x3f/0x90
> > >  entry_SYSCALL_64_after_hwframe+0x72/0xdc
> > >
> > > The logic in tcp_bpf_recvmsg_parser is as follows:
> > >
> > > msg_bytes_ready:
> > >       copied = sk_msg_recvmsg(sk, psock, msg, len, flags);
> > >       if (!copied) {
> > >               wait data;
> > >               goto msg_bytes_ready;
> > >       }
> > >
> > > In this case, "copied" alway is 0, the infinite loop occurs.
> > >
> > > According to the Linux system call man page, 0 should be returned in
> > > this case. Therefore, in tcp_bpf_recvmsg_parser(), if the length is
> > > 0, directly return.
> > >
> > > Also modify several other functions with the same problem.
> > >
> > > Fixes: 1f5be6b3b063 ("udp: Implement udp_bpf_recvmsg() for sockmap")
> > > Fixes: 9825d866ce0d ("af_unix: Implement unix_dgram_bpf_recvmsg()")
> > > Fixes: c5d2177a72a1 ("bpf, sockmap: Fix race in ingress receive
> > > verdict with redirect to self")
> > > Fixes: 604326b41a6f ("bpf, sockmap: convert to generic sk_msg
> > > interface")
> > > Signed-off-by: Liu Jian <liujian56@huawei.com>
> > > ---
> >
> > Thanks.
> >
> > Acked-by: John Fastabend <john.fastabend@gmail.com>
> 
> Thanks John.
> 
> Liu,
> 
> could you please change if (len == 0) to if (!len) and respin with John's ack.
> Thanks
Okay, I will send v2. 
Thanks.
diff mbox series

Patch

diff --git a/net/ipv4/tcp_bpf.c b/net/ipv4/tcp_bpf.c
index cf26d65ca389..36b52ae519ab 100644
--- a/net/ipv4/tcp_bpf.c
+++ b/net/ipv4/tcp_bpf.c
@@ -186,6 +186,9 @@  static int tcp_bpf_recvmsg_parser(struct sock *sk,
 	if (unlikely(flags & MSG_ERRQUEUE))
 		return inet_recv_error(sk, msg, len, addr_len);
 
+	if (len == 0)
+		return 0;
+
 	psock = sk_psock_get(sk);
 	if (unlikely(!psock))
 		return tcp_recvmsg(sk, msg, len, flags, addr_len);
@@ -244,6 +247,9 @@  static int tcp_bpf_recvmsg(struct sock *sk, struct msghdr *msg, size_t len,
 	if (unlikely(flags & MSG_ERRQUEUE))
 		return inet_recv_error(sk, msg, len, addr_len);
 
+	if (len == 0)
+		return 0;
+
 	psock = sk_psock_get(sk);
 	if (unlikely(!psock))
 		return tcp_recvmsg(sk, msg, len, flags, addr_len);
diff --git a/net/ipv4/udp_bpf.c b/net/ipv4/udp_bpf.c
index e5dc91d0e079..a2a9d67bd3ff 100644
--- a/net/ipv4/udp_bpf.c
+++ b/net/ipv4/udp_bpf.c
@@ -68,6 +68,9 @@  static int udp_bpf_recvmsg(struct sock *sk, struct msghdr *msg, size_t len,
 	if (unlikely(flags & MSG_ERRQUEUE))
 		return inet_recv_error(sk, msg, len, addr_len);
 
+	if (len == 0)
+		return 0;
+
 	psock = sk_psock_get(sk);
 	if (unlikely(!psock))
 		return sk_udp_recvmsg(sk, msg, len, flags, addr_len);
diff --git a/net/unix/unix_bpf.c b/net/unix/unix_bpf.c
index e9bf15513961..851c4719f8a9 100644
--- a/net/unix/unix_bpf.c
+++ b/net/unix/unix_bpf.c
@@ -54,6 +54,9 @@  static int unix_bpf_recvmsg(struct sock *sk, struct msghdr *msg,
 	struct sk_psock *psock;
 	int copied;
 
+	if (len == 0)
+		return 0;
+
 	psock = sk_psock_get(sk);
 	if (unlikely(!psock))
 		return __unix_recvmsg(sk, msg, len, flags);