diff mbox series

[v5.10] bpf, skmsg: Fix NULL pointer dereference in sk_psock_skb_ingress_enqueue

Message ID 1721196416-13046-1-git-send-email-ashwin.kamat@broadcom.com (mailing list archive)
State Not Applicable
Delegated to: BPF
Headers show
Series [v5.10] bpf, skmsg: Fix NULL pointer dereference in sk_psock_skb_ingress_enqueue | expand

Checks

Context Check Description
netdev/tree_selection success Not a local patch
bpf/vmtest-bpf-PR success PR summary
bpf/vmtest-bpf-VM_Test-13 success Logs for s390x-gcc / test (test_maps, false, 360) / test_maps on s390x with gcc
bpf/vmtest-bpf-VM_Test-21 success Logs for x86_64-gcc / test (test_maps, false, 360) / test_maps on x86_64 with gcc
bpf/vmtest-bpf-VM_Test-3 success Logs for Validate matrix.py
bpf/vmtest-bpf-VM_Test-9 success Logs for aarch64-gcc / test (test_verifier, false, 360) / test_verifier on aarch64 with gcc
bpf/vmtest-bpf-VM_Test-2 success Logs for Unittests
bpf/vmtest-bpf-VM_Test-5 success Logs for aarch64-gcc / build-release
bpf/vmtest-bpf-VM_Test-7 success Logs for aarch64-gcc / test (test_progs, false, 360) / test_progs on aarch64 with gcc
bpf/vmtest-bpf-VM_Test-6 success Logs for aarch64-gcc / test (test_maps, false, 360) / test_maps on aarch64 with gcc
bpf/vmtest-bpf-VM_Test-33 success Logs for x86_64-llvm-17 / test (test_verifier, false, 360) / test_verifier on x86_64 with llvm-17
bpf/vmtest-bpf-VM_Test-40 success Logs for x86_64-llvm-18 / test (test_progs_no_alu32, false, 360) / test_progs_no_alu32 on x86_64 with llvm-18
bpf/vmtest-bpf-VM_Test-18 success Logs for set-matrix
bpf/vmtest-bpf-VM_Test-22 success Logs for x86_64-gcc / test (test_progs, false, 360) / test_progs on x86_64 with gcc
bpf/vmtest-bpf-VM_Test-1 success Logs for ShellCheck
bpf/vmtest-bpf-VM_Test-16 success Logs for s390x-gcc / test (test_verifier, false, 360) / test_verifier on s390x with gcc
bpf/vmtest-bpf-VM_Test-4 success Logs for aarch64-gcc / build / build for aarch64 with gcc
bpf/vmtest-bpf-VM_Test-28 success Logs for x86_64-llvm-17 / build / build for x86_64 with llvm-17
bpf/vmtest-bpf-VM_Test-14 success Logs for s390x-gcc / test (test_progs, false, 360) / test_progs on s390x with gcc
bpf/vmtest-bpf-VM_Test-17 success Logs for s390x-gcc / veristat
bpf/vmtest-bpf-VM_Test-0 success Logs for Lint
bpf/vmtest-bpf-VM_Test-10 success Logs for aarch64-gcc / veristat
bpf/vmtest-bpf-VM_Test-11 success Logs for s390x-gcc / build / build for s390x with gcc
bpf/vmtest-bpf-VM_Test-36 success Logs for x86_64-llvm-18 / build-release / build for x86_64 with llvm-18-O2
bpf/vmtest-bpf-VM_Test-42 success Logs for x86_64-llvm-18 / veristat
bpf/vmtest-bpf-VM_Test-25 success Logs for x86_64-gcc / test (test_progs_parallel, true, 30) / test_progs_parallel on x86_64 with gcc
bpf/vmtest-bpf-VM_Test-24 success Logs for x86_64-gcc / test (test_progs_no_alu32_parallel, true, 30) / test_progs_no_alu32_parallel on x86_64 with gcc
bpf/vmtest-bpf-VM_Test-41 success Logs for x86_64-llvm-18 / test (test_verifier, false, 360) / test_verifier on x86_64 with llvm-18
bpf/vmtest-bpf-VM_Test-32 success Logs for x86_64-llvm-17 / test (test_progs_no_alu32, false, 360) / test_progs_no_alu32 on x86_64 with llvm-17
bpf/vmtest-bpf-VM_Test-29 success Logs for x86_64-llvm-17 / build-release / build for x86_64 with llvm-17-O2
bpf/vmtest-bpf-VM_Test-20 success Logs for x86_64-gcc / build-release
bpf/vmtest-bpf-VM_Test-26 success Logs for x86_64-gcc / test (test_verifier, false, 360) / test_verifier on x86_64 with gcc
bpf/vmtest-bpf-VM_Test-31 success Logs for x86_64-llvm-17 / test (test_progs, false, 360) / test_progs on x86_64 with llvm-17
bpf/vmtest-bpf-VM_Test-38 success Logs for x86_64-llvm-18 / test (test_progs, false, 360) / test_progs on x86_64 with llvm-18
bpf/vmtest-bpf-VM_Test-12 success Logs for s390x-gcc / build-release
bpf/vmtest-bpf-VM_Test-27 success Logs for x86_64-gcc / veristat / veristat on x86_64 with gcc
bpf/vmtest-bpf-VM_Test-37 success Logs for x86_64-llvm-18 / test (test_maps, false, 360) / test_maps on x86_64 with llvm-18
bpf/vmtest-bpf-VM_Test-30 success Logs for x86_64-llvm-17 / test (test_maps, false, 360) / test_maps on x86_64 with llvm-17
bpf/vmtest-bpf-VM_Test-39 success Logs for x86_64-llvm-18 / test (test_progs_cpuv4, false, 360) / test_progs_cpuv4 on x86_64 with llvm-18
bpf/vmtest-bpf-VM_Test-34 success Logs for x86_64-llvm-17 / veristat
bpf/vmtest-bpf-VM_Test-15 success Logs for s390x-gcc / test (test_progs_no_alu32, false, 360) / test_progs_no_alu32 on s390x with gcc
bpf/vmtest-bpf-VM_Test-8 success Logs for aarch64-gcc / test (test_progs_no_alu32, false, 360) / test_progs_no_alu32 on aarch64 with gcc
bpf/vmtest-bpf-VM_Test-19 success Logs for x86_64-gcc / build / build for x86_64 with gcc
bpf/vmtest-bpf-VM_Test-23 success Logs for x86_64-gcc / test (test_progs_no_alu32, false, 360) / test_progs_no_alu32 on x86_64 with gcc
bpf/vmtest-bpf-VM_Test-35 success Logs for x86_64-llvm-18 / build / build for x86_64 with llvm-18

Commit Message

Ashwin Kamat July 17, 2024, 6:06 a.m. UTC 
From: Jason Xing <kernelxing@tencent.com>

[ Upstream commit 6648e613226e18897231ab5e42ffc29e63fa3365 ]

Fix NULL pointer data-races in sk_psock_skb_ingress_enqueue() which
syzbot reported [1].

[1]
BUG: KCSAN: data-race in sk_psock_drop / sk_psock_skb_ingress_enqueue

write to 0xffff88814b3278b8 of 8 bytes by task 10724 on cpu 1:
 sk_psock_stop_verdict net/core/skmsg.c:1257 [inline]
 sk_psock_drop+0x13e/0x1f0 net/core/skmsg.c:843
 sk_psock_put include/linux/skmsg.h:459 [inline]
 sock_map_close+0x1a7/0x260 net/core/sock_map.c:1648
 unix_release+0x4b/0x80 net/unix/af_unix.c:1048
 __sock_release net/socket.c:659 [inline]
 sock_close+0x68/0x150 net/socket.c:1421
 __fput+0x2c1/0x660 fs/file_table.c:422
 __fput_sync+0x44/0x60 fs/file_table.c:507
 __do_sys_close fs/open.c:1556 [inline]
 __se_sys_close+0x101/0x1b0 fs/open.c:1541
 __x64_sys_close+0x1f/0x30 fs/open.c:1541
 do_syscall_64+0xd3/0x1d0
 entry_SYSCALL_64_after_hwframe+0x6d/0x75

read to 0xffff88814b3278b8 of 8 bytes by task 10713 on cpu 0:
 sk_psock_data_ready include/linux/skmsg.h:464 [inline]
 sk_psock_skb_ingress_enqueue+0x32d/0x390 net/core/skmsg.c:555
 sk_psock_skb_ingress_self+0x185/0x1e0 net/core/skmsg.c:606
 sk_psock_verdict_apply net/core/skmsg.c:1008 [inline]
 sk_psock_verdict_recv+0x3e4/0x4a0 net/core/skmsg.c:1202
 unix_read_skb net/unix/af_unix.c:2546 [inline]
 unix_stream_read_skb+0x9e/0xf0 net/unix/af_unix.c:2682
 sk_psock_verdict_data_ready+0x77/0x220 net/core/skmsg.c:1223
 unix_stream_sendmsg+0x527/0x860 net/unix/af_unix.c:2339
 sock_sendmsg_nosec net/socket.c:730 [inline]
 __sock_sendmsg+0x140/0x180 net/socket.c:745
 ____sys_sendmsg+0x312/0x410 net/socket.c:2584
 ___sys_sendmsg net/socket.c:2638 [inline]
 __sys_sendmsg+0x1e9/0x280 net/socket.c:2667
 __do_sys_sendmsg net/socket.c:2676 [inline]
 __se_sys_sendmsg net/socket.c:2674 [inline]
 __x64_sys_sendmsg+0x46/0x50 net/socket.c:2674
 do_syscall_64+0xd3/0x1d0
 entry_SYSCALL_64_after_hwframe+0x6d/0x75

value changed: 0xffffffff83d7feb0 -> 0x0000000000000000

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 10713 Comm: syz-executor.4 Tainted: G        W          6.8.0-syzkaller-08951-gfe46a7dd189e #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/29/2024

Prior to this, commit 4cd12c6065df ("bpf, sockmap: Fix NULL pointer
dereference in sk_psock_verdict_data_ready()") fixed one NULL pointer
similarly due to no protection of saved_data_ready. Here is another
different caller causing the same issue because of the same reason. So
we should protect it with sk_callback_lock read lock because the writer
side in the sk_psock_drop() uses "write_lock_bh(&sk->sk_callback_lock);".

To avoid errors that could happen in future, I move those two pairs of
lock into the sk_psock_data_ready(), which is suggested by John Fastabend.

Fixes: 604326b41a6f ("bpf, sockmap: convert to generic sk_msg interface")
Reported-by: syzbot+aa8c8ec2538929f18f2d@syzkaller.appspotmail.com
Signed-off-by: Jason Xing <kernelxing@tencent.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: John Fastabend <john.fastabend@gmail.com>
Closes: https://syzkaller.appspot.com/bug?extid=aa8c8ec2538929f18f2d
Link: https://lore.kernel.org/all/20240329134037.92124-1-kerneljasonxing@gmail.com
Link: https://lore.kernel.org/bpf/20240404021001.94815-1-kerneljasonxing@gmail.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
[Ashwin: Regenerated the patch for v5.10]
Signed-off-by: Ashwin Dayanand Kamat <ashwin.kamat@broadcom.com>
---
 include/linux/skmsg.h | 2 ++
 1 file changed, 2 insertions(+)

Comments

Greg KH July 23, 2024, 1:25 p.m. UTC | #1 
On Wed, Jul 17, 2024 at 11:36:56AM +0530, Ashwin Kamat wrote:
> From: Jason Xing <kernelxing@tencent.com>
> 
> [ Upstream commit 6648e613226e18897231ab5e42ffc29e63fa3365 ]
> 
> Fix NULL pointer data-races in sk_psock_skb_ingress_enqueue() which
> syzbot reported [1].
> 
> [1]
> BUG: KCSAN: data-race in sk_psock_drop / sk_psock_skb_ingress_enqueue
> 
> write to 0xffff88814b3278b8 of 8 bytes by task 10724 on cpu 1:
>  sk_psock_stop_verdict net/core/skmsg.c:1257 [inline]
>  sk_psock_drop+0x13e/0x1f0 net/core/skmsg.c:843
>  sk_psock_put include/linux/skmsg.h:459 [inline]
>  sock_map_close+0x1a7/0x260 net/core/sock_map.c:1648
>  unix_release+0x4b/0x80 net/unix/af_unix.c:1048
>  __sock_release net/socket.c:659 [inline]
>  sock_close+0x68/0x150 net/socket.c:1421
>  __fput+0x2c1/0x660 fs/file_table.c:422
>  __fput_sync+0x44/0x60 fs/file_table.c:507
>  __do_sys_close fs/open.c:1556 [inline]
>  __se_sys_close+0x101/0x1b0 fs/open.c:1541
>  __x64_sys_close+0x1f/0x30 fs/open.c:1541
>  do_syscall_64+0xd3/0x1d0
>  entry_SYSCALL_64_after_hwframe+0x6d/0x75
> 
> read to 0xffff88814b3278b8 of 8 bytes by task 10713 on cpu 0:
>  sk_psock_data_ready include/linux/skmsg.h:464 [inline]
>  sk_psock_skb_ingress_enqueue+0x32d/0x390 net/core/skmsg.c:555
>  sk_psock_skb_ingress_self+0x185/0x1e0 net/core/skmsg.c:606
>  sk_psock_verdict_apply net/core/skmsg.c:1008 [inline]
>  sk_psock_verdict_recv+0x3e4/0x4a0 net/core/skmsg.c:1202
>  unix_read_skb net/unix/af_unix.c:2546 [inline]
>  unix_stream_read_skb+0x9e/0xf0 net/unix/af_unix.c:2682
>  sk_psock_verdict_data_ready+0x77/0x220 net/core/skmsg.c:1223
>  unix_stream_sendmsg+0x527/0x860 net/unix/af_unix.c:2339
>  sock_sendmsg_nosec net/socket.c:730 [inline]
>  __sock_sendmsg+0x140/0x180 net/socket.c:745
>  ____sys_sendmsg+0x312/0x410 net/socket.c:2584
>  ___sys_sendmsg net/socket.c:2638 [inline]
>  __sys_sendmsg+0x1e9/0x280 net/socket.c:2667
>  __do_sys_sendmsg net/socket.c:2676 [inline]
>  __se_sys_sendmsg net/socket.c:2674 [inline]
>  __x64_sys_sendmsg+0x46/0x50 net/socket.c:2674
>  do_syscall_64+0xd3/0x1d0
>  entry_SYSCALL_64_after_hwframe+0x6d/0x75
> 
> value changed: 0xffffffff83d7feb0 -> 0x0000000000000000
> 
> Reported by Kernel Concurrency Sanitizer on:
> CPU: 0 PID: 10713 Comm: syz-executor.4 Tainted: G        W          6.8.0-syzkaller-08951-gfe46a7dd189e #0
> Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/29/2024
> 
> Prior to this, commit 4cd12c6065df ("bpf, sockmap: Fix NULL pointer
> dereference in sk_psock_verdict_data_ready()") fixed one NULL pointer
> similarly due to no protection of saved_data_ready. Here is another
> different caller causing the same issue because of the same reason. So
> we should protect it with sk_callback_lock read lock because the writer
> side in the sk_psock_drop() uses "write_lock_bh(&sk->sk_callback_lock);".
> 
> To avoid errors that could happen in future, I move those two pairs of
> lock into the sk_psock_data_ready(), which is suggested by John Fastabend.
> 
> Fixes: 604326b41a6f ("bpf, sockmap: convert to generic sk_msg interface")
> Reported-by: syzbot+aa8c8ec2538929f18f2d@syzkaller.appspotmail.com
> Signed-off-by: Jason Xing <kernelxing@tencent.com>
> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
> Reviewed-by: John Fastabend <john.fastabend@gmail.com>
> Closes: https://syzkaller.appspot.com/bug?extid=aa8c8ec2538929f18f2d
> Link: https://lore.kernel.org/all/20240329134037.92124-1-kerneljasonxing@gmail.com
> Link: https://lore.kernel.org/bpf/20240404021001.94815-1-kerneljasonxing@gmail.com
> Signed-off-by: Sasha Levin <sashal@kernel.org>
> [Ashwin: Regenerated the patch for v5.10]
> Signed-off-by: Ashwin Dayanand Kamat <ashwin.kamat@broadcom.com>
> ---
>  include/linux/skmsg.h | 2 ++
>  1 file changed, 2 insertions(+)

Now queued up, thanks.

greg k-h
diff mbox series

Patch

diff --git a/include/linux/skmsg.h b/include/linux/skmsg.h
index 1138dd3071db..a197c9a49e97 100644
--- a/include/linux/skmsg.h
+++ b/include/linux/skmsg.h
@@ -406,10 +406,12 @@  static inline void sk_psock_put(struct sock *sk, struct sk_psock *psock)
 
 static inline void sk_psock_data_ready(struct sock *sk, struct sk_psock *psock)
 {
+	read_lock_bh(&sk->sk_callback_lock);
 	if (psock->parser.enabled)
 		psock->parser.saved_data_ready(sk);
 	else
 		sk->sk_data_ready(sk);
+	read_unlock_bh(&sk->sk_callback_lock);
 }
 
 static inline void psock_set_prog(struct bpf_prog **pprog,