4.9-stable patches

added patches:
	kcm-avoid-potential-race-in-kcm_tx_work.patch
	tcp-cdg-allow-tcp_cdg_release-to-be-called-multiple-times.patch

diff --git a/queue-4.9/kcm-avoid-potential-race-in-kcm_tx_work.patch b/queue-4.9/kcm-avoid-potential-race-in-kcm_tx_work.patch
new file mode 100644 (file)
index 0000000..c9981bb
--- /dev/null
+++ b/queue-4.9/kcm-avoid-potential-race-in-kcm_tx_work.patch
@@ -0,0 +1,72 @@
+From ec7eede369fe5b0d085ac51fdbb95184f87bfc6c Mon Sep 17 00:00:00 2001
+From: Eric Dumazet <edumazet@google.com>
+Date: Wed, 12 Oct 2022 13:34:12 +0000
+Subject: kcm: avoid potential race in kcm_tx_work
+
+From: Eric Dumazet <edumazet@google.com>
+
+commit ec7eede369fe5b0d085ac51fdbb95184f87bfc6c upstream.
+
+syzbot found that kcm_tx_work() could crash [1] in:
+
+       /* Primarily for SOCK_SEQPACKET sockets */
+       if (likely(sk->sk_socket) &&
+           test_bit(SOCK_NOSPACE, &sk->sk_socket->flags)) {
+<<*>>  clear_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
+               sk->sk_write_space(sk);
+       }
+
+I think the reason is that another thread might concurrently
+run in kcm_release() and call sock_orphan(sk) while sk is not
+locked. kcm_tx_work() find sk->sk_socket being NULL.
+
+[1]
+BUG: KASAN: null-ptr-deref in instrument_atomic_write include/linux/instrumented.h:86 [inline]
+BUG: KASAN: null-ptr-deref in clear_bit include/asm-generic/bitops/instrumented-atomic.h:41 [inline]
+BUG: KASAN: null-ptr-deref in kcm_tx_work+0xff/0x160 net/kcm/kcmsock.c:742
+Write of size 8 at addr 0000000000000008 by task kworker/u4:3/53
+
+CPU: 0 PID: 53 Comm: kworker/u4:3 Not tainted 5.19.0-rc3-next-20220621-syzkaller #0
+Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
+Workqueue: kkcmd kcm_tx_work
+Call Trace:
+<TASK>
+__dump_stack lib/dump_stack.c:88 [inline]
+dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106
+kasan_report+0xbe/0x1f0 mm/kasan/report.c:495
+check_region_inline mm/kasan/generic.c:183 [inline]
+kasan_check_range+0x13d/0x180 mm/kasan/generic.c:189
+instrument_atomic_write include/linux/instrumented.h:86 [inline]
+clear_bit include/asm-generic/bitops/instrumented-atomic.h:41 [inline]
+kcm_tx_work+0xff/0x160 net/kcm/kcmsock.c:742
+process_one_work+0x996/0x1610 kernel/workqueue.c:2289
+worker_thread+0x665/0x1080 kernel/workqueue.c:2436
+kthread+0x2e9/0x3a0 kernel/kthread.c:376
+ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:302
+</TASK>
+
+Fixes: ab7ac4eb9832 ("kcm: Kernel Connection Multiplexor module")
+Reported-by: syzbot <syzkaller@googlegroups.com>
+Signed-off-by: Eric Dumazet <edumazet@google.com>
+Cc: Tom Herbert <tom@herbertland.com>
+Link: https://lore.kernel.org/r/20221012133412.519394-1-edumazet@google.com
+Signed-off-by: Jakub Kicinski <kuba@kernel.org>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+---
+ net/kcm/kcmsock.c |    2 +-
+ 1 file changed, 1 insertion(+), 1 deletion(-)
+
+--- a/net/kcm/kcmsock.c
++++ b/net/kcm/kcmsock.c
+@@ -1850,10 +1850,10 @@ static int kcm_release(struct socket *so
+       kcm = kcm_sk(sk);
+       mux = kcm->mux;
+ 
++      lock_sock(sk);
+       sock_orphan(sk);
+       kfree_skb(kcm->seq_skb);
+ 
+-      lock_sock(sk);
+       /* Purge queue under lock to avoid race condition with tx_work trying
+        * to act when queue is nonempty. If tx_work runs after this point
+        * it will just return.

diff --git a/queue-4.9/series b/queue-4.9/series
index 0a20bba85c7d6c708497fcd396d617993ceceb0b..086c022e755efea9d22681786d8d0281480a6f26 100644 (file)
--- a/queue-4.9/series
+++ b/queue-4.9/series
@@ -64,3 +64,5 @@ mmc-core-properly-select-voltage-range-without-power-cycle.patch
 misc-vmw_vmci-fix-an-infoleak-in-vmci_host_do_receive_datagram.patch
 nilfs2-fix-use-after-free-bug-of-ns_writer-on-remount.patch
 serial-8250-flush-dma-rx-on-rlsi.patch
+tcp-cdg-allow-tcp_cdg_release-to-be-called-multiple-times.patch
+kcm-avoid-potential-race-in-kcm_tx_work.patch

diff --git a/queue-4.9/tcp-cdg-allow-tcp_cdg_release-to-be-called-multiple-times.patch b/queue-4.9/tcp-cdg-allow-tcp_cdg_release-to-be-called-multiple-times.patch
new file mode 100644 (file)
index 0000000..5dd806b
--- /dev/null
+++ b/queue-4.9/tcp-cdg-allow-tcp_cdg_release-to-be-called-multiple-times.patch
@@ -0,0 +1,155 @@
+From 72e560cb8c6f80fc2b4afc5d3634a32465e13a51 Mon Sep 17 00:00:00 2001
+From: Eric Dumazet <edumazet@google.com>
+Date: Tue, 11 Oct 2022 15:07:48 -0700
+Subject: tcp: cdg: allow tcp_cdg_release() to be called multiple times
+
+From: Eric Dumazet <edumazet@google.com>
+
+commit 72e560cb8c6f80fc2b4afc5d3634a32465e13a51 upstream.
+
+Apparently, mptcp is able to call tcp_disconnect() on an already
+disconnected flow. This is generally fine, unless current congestion
+control is CDG, because it might trigger a double-free [1]
+
+Instead of fixing MPTCP, and future bugs, we can make tcp_disconnect()
+more resilient.
+
+[1]
+BUG: KASAN: double-free in slab_free mm/slub.c:3539 [inline]
+BUG: KASAN: double-free in kfree+0xe2/0x580 mm/slub.c:4567
+
+CPU: 0 PID: 3645 Comm: kworker/0:7 Not tainted 6.0.0-syzkaller-02734-g0326074ff465 #0
+Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/22/2022
+Workqueue: events mptcp_worker
+Call Trace:
+<TASK>
+__dump_stack lib/dump_stack.c:88 [inline]
+dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106
+print_address_description mm/kasan/report.c:317 [inline]
+print_report.cold+0x2ba/0x719 mm/kasan/report.c:433
+kasan_report_invalid_free+0x81/0x190 mm/kasan/report.c:462
+____kasan_slab_free+0x18b/0x1c0 mm/kasan/common.c:356
+kasan_slab_free include/linux/kasan.h:200 [inline]
+slab_free_hook mm/slub.c:1759 [inline]
+slab_free_freelist_hook+0x8b/0x1c0 mm/slub.c:1785
+slab_free mm/slub.c:3539 [inline]
+kfree+0xe2/0x580 mm/slub.c:4567
+tcp_disconnect+0x980/0x1e20 net/ipv4/tcp.c:3145
+__mptcp_close_ssk+0x5ca/0x7e0 net/mptcp/protocol.c:2327
+mptcp_do_fastclose net/mptcp/protocol.c:2592 [inline]
+mptcp_worker+0x78c/0xff0 net/mptcp/protocol.c:2627
+process_one_work+0x991/0x1610 kernel/workqueue.c:2289
+worker_thread+0x665/0x1080 kernel/workqueue.c:2436
+kthread+0x2e4/0x3a0 kernel/kthread.c:376
+ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306
+</TASK>
+
+Allocated by task 3671:
+kasan_save_stack+0x1e/0x40 mm/kasan/common.c:38
+kasan_set_track mm/kasan/common.c:45 [inline]
+set_alloc_info mm/kasan/common.c:437 [inline]
+____kasan_kmalloc mm/kasan/common.c:516 [inline]
+____kasan_kmalloc mm/kasan/common.c:475 [inline]
+__kasan_kmalloc+0xa9/0xd0 mm/kasan/common.c:525
+kmalloc_array include/linux/slab.h:640 [inline]
+kcalloc include/linux/slab.h:671 [inline]
+tcp_cdg_init+0x10d/0x170 net/ipv4/tcp_cdg.c:380
+tcp_init_congestion_control+0xab/0x550 net/ipv4/tcp_cong.c:193
+tcp_reinit_congestion_control net/ipv4/tcp_cong.c:217 [inline]
+tcp_set_congestion_control+0x96c/0xaa0 net/ipv4/tcp_cong.c:391
+do_tcp_setsockopt+0x505/0x2320 net/ipv4/tcp.c:3513
+tcp_setsockopt+0xd4/0x100 net/ipv4/tcp.c:3801
+mptcp_setsockopt+0x35f/0x2570 net/mptcp/sockopt.c:844
+__sys_setsockopt+0x2d6/0x690 net/socket.c:2252
+__do_sys_setsockopt net/socket.c:2263 [inline]
+__se_sys_setsockopt net/socket.c:2260 [inline]
+__x64_sys_setsockopt+0xba/0x150 net/socket.c:2260
+do_syscall_x64 arch/x86/entry/common.c:50 [inline]
+do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
+entry_SYSCALL_64_after_hwframe+0x63/0xcd
+
+Freed by task 16:
+kasan_save_stack+0x1e/0x40 mm/kasan/common.c:38
+kasan_set_track+0x21/0x30 mm/kasan/common.c:45
+kasan_set_free_info+0x20/0x30 mm/kasan/generic.c:370
+____kasan_slab_free mm/kasan/common.c:367 [inline]
+____kasan_slab_free+0x166/0x1c0 mm/kasan/common.c:329
+kasan_slab_free include/linux/kasan.h:200 [inline]
+slab_free_hook mm/slub.c:1759 [inline]
+slab_free_freelist_hook+0x8b/0x1c0 mm/slub.c:1785
+slab_free mm/slub.c:3539 [inline]
+kfree+0xe2/0x580 mm/slub.c:4567
+tcp_cleanup_congestion_control+0x70/0x120 net/ipv4/tcp_cong.c:226
+tcp_v4_destroy_sock+0xdd/0x750 net/ipv4/tcp_ipv4.c:2254
+tcp_v6_destroy_sock+0x11/0x20 net/ipv6/tcp_ipv6.c:1969
+inet_csk_destroy_sock+0x196/0x440 net/ipv4/inet_connection_sock.c:1157
+tcp_done+0x23b/0x340 net/ipv4/tcp.c:4649
+tcp_rcv_state_process+0x40e7/0x4990 net/ipv4/tcp_input.c:6624
+tcp_v6_do_rcv+0x3fc/0x13c0 net/ipv6/tcp_ipv6.c:1525
+tcp_v6_rcv+0x2e8e/0x3830 net/ipv6/tcp_ipv6.c:1759
+ip6_protocol_deliver_rcu+0x2db/0x1950 net/ipv6/ip6_input.c:439
+ip6_input_finish+0x14c/0x2c0 net/ipv6/ip6_input.c:484
+NF_HOOK include/linux/netfilter.h:302 [inline]
+NF_HOOK include/linux/netfilter.h:296 [inline]
+ip6_input+0x9c/0xd0 net/ipv6/ip6_input.c:493
+dst_input include/net/dst.h:455 [inline]
+ip6_rcv_finish+0x193/0x2c0 net/ipv6/ip6_input.c:79
+ip_sabotage_in net/bridge/br_netfilter_hooks.c:874 [inline]
+ip_sabotage_in+0x1fa/0x260 net/bridge/br_netfilter_hooks.c:865
+nf_hook_entry_hookfn include/linux/netfilter.h:142 [inline]
+nf_hook_slow+0xc5/0x1f0 net/netfilter/core.c:614
+nf_hook.constprop.0+0x3ac/0x650 include/linux/netfilter.h:257
+NF_HOOK include/linux/netfilter.h:300 [inline]
+ipv6_rcv+0x9e/0x380 net/ipv6/ip6_input.c:309
+__netif_receive_skb_one_core+0x114/0x180 net/core/dev.c:5485
+__netif_receive_skb+0x1f/0x1c0 net/core/dev.c:5599
+netif_receive_skb_internal net/core/dev.c:5685 [inline]
+netif_receive_skb+0x12f/0x8d0 net/core/dev.c:5744
+NF_HOOK include/linux/netfilter.h:302 [inline]
+NF_HOOK include/linux/netfilter.h:296 [inline]
+br_pass_frame_up+0x303/0x410 net/bridge/br_input.c:68
+br_handle_frame_finish+0x909/0x1aa0 net/bridge/br_input.c:199
+br_nf_hook_thresh+0x2f8/0x3d0 net/bridge/br_netfilter_hooks.c:1041
+br_nf_pre_routing_finish_ipv6+0x695/0xef0 net/bridge/br_netfilter_ipv6.c:207
+NF_HOOK include/linux/netfilter.h:302 [inline]
+br_nf_pre_routing_ipv6+0x417/0x7c0 net/bridge/br_netfilter_ipv6.c:237
+br_nf_pre_routing+0x1496/0x1fe0 net/bridge/br_netfilter_hooks.c:507
+nf_hook_entry_hookfn include/linux/netfilter.h:142 [inline]
+nf_hook_bridge_pre net/bridge/br_input.c:255 [inline]
+br_handle_frame+0x9c9/0x12d0 net/bridge/br_input.c:399
+__netif_receive_skb_core+0x9fe/0x38f0 net/core/dev.c:5379
+__netif_receive_skb_one_core+0xae/0x180 net/core/dev.c:5483
+__netif_receive_skb+0x1f/0x1c0 net/core/dev.c:5599
+process_backlog+0x3a0/0x7c0 net/core/dev.c:5927
+__napi_poll+0xb3/0x6d0 net/core/dev.c:6494
+napi_poll net/core/dev.c:6561 [inline]
+net_rx_action+0x9c1/0xd90 net/core/dev.c:6672
+__do_softirq+0x1d0/0x9c8 kernel/softirq.c:571
+
+Fixes: 2b0a8c9eee81 ("tcp: add CDG congestion control")
+Reported-by: syzbot <syzkaller@googlegroups.com>
+Signed-off-by: Eric Dumazet <edumazet@google.com>
+Signed-off-by: David S. Miller <davem@davemloft.net>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+---
+ net/ipv4/tcp_cdg.c |    2 ++
+ 1 file changed, 2 insertions(+)
+
+--- a/net/ipv4/tcp_cdg.c
++++ b/net/ipv4/tcp_cdg.c
+@@ -382,6 +382,7 @@ static void tcp_cdg_init(struct sock *sk
+       struct cdg *ca = inet_csk_ca(sk);
+       struct tcp_sock *tp = tcp_sk(sk);
+ 
++      ca->gradients = NULL;
+       /* We silently fall back to window = 1 if allocation fails. */
+       if (window > 1)
+               ca->gradients = kcalloc(window, sizeof(ca->gradients[0]),
+@@ -395,6 +396,7 @@ static void tcp_cdg_release(struct sock
+       struct cdg *ca = inet_csk_ca(sk);
+ 
+       kfree(ca->gradients);
++      ca->gradients = NULL;
+ }
+ 
+ struct tcp_congestion_ops tcp_cdg __read_mostly = {