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MAINTAINERS: Update the MODULE SUPPORT section#62

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MAINTAINERS: Update the MODULE SUPPORT section#62
modules-kpd-app[bot] wants to merge 2 commits intomodules-next_basefrom
series/941087=>modules-next

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Pull request for series with
subject: MAINTAINERS: Update the MODULE SUPPORT section
version: 1
url: https://patchwork.kernel.org/project/linux-modules/list/?series=941087

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Upstream branch: afa9286
series: https://patchwork.kernel.org/project/linux-modules/list/?series=941087
version: 1

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Upstream branch: afa9286
series: https://patchwork.kernel.org/project/linux-modules/list/?series=941087
version: 1

@modules-kpd-app modules-kpd-app bot force-pushed the series/941087=>modules-next branch from f9e9792 to fec171d Compare March 6, 2025 17:12
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Upstream branch: afa9286
series: https://patchwork.kernel.org/project/linux-modules/list/?series=941087
version: 1

@modules-kpd-app modules-kpd-app bot force-pushed the series/941087=>modules-next branch from fec171d to 5b7aa9c Compare March 6, 2025 17:27
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Upstream branch: 085c5e3
series: https://patchwork.kernel.org/project/linux-modules/list/?series=941087
version: 1

Change my role for MODULE SUPPORT from a reviewer to a maintainer. We
started to rotate its maintainership and I currently look after the modules
tree. This not being reflected in MAINTAINERS proved to confuse folks.

Add lib/tests/module/ and tools/testing/selftests/module/ to maintained
files. They were introduced previously by commit 84b4a51 ("selftests:
add new kallsyms selftests").

Signed-off-by: Petr Pavlu <petr.pavlu@suse.com>
Acked-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Reviewed-by: Luis Chamberlain <mcgrof@kernel.org>
@modules-kpd-app modules-kpd-app bot force-pushed the series/941087=>modules-next branch from 5b7aa9c to 137a29f Compare March 18, 2025 22:56
@modules-kpd-app modules-kpd-app bot force-pushed the modules-next_base branch from 7c2b408 to 2996654 Compare April 7, 2025 01:58
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At least one diff in series https://patchwork.kernel.org/project/linux-modules/list/?series=941087 irrelevant now. Closing PR.

@modules-kpd-app modules-kpd-app bot added accepted and removed new labels Apr 7, 2025
@modules-kpd-app modules-kpd-app bot closed this Apr 7, 2025
@modules-kpd-app modules-kpd-app bot deleted the series/941087=>modules-next branch April 7, 2025 01:59
dagomez137 pushed a commit that referenced this pull request Sep 22, 2025
syzbot reported the splat below where a socket had tcp_sk(sk)->fastopen_rsk
in the TCP_ESTABLISHED state. [0]

syzbot reused the server-side TCP Fast Open socket as a new client before
the TFO socket completes 3WHS:

  1. accept()
  2. connect(AF_UNSPEC)
  3. connect() to another destination

As of accept(), sk->sk_state is TCP_SYN_RECV, and tcp_disconnect() changes
it to TCP_CLOSE and makes connect() possible, which restarts timers.

Since tcp_disconnect() forgot to clear tcp_sk(sk)->fastopen_rsk, the
retransmit timer triggered the warning and the intended packet was not
retransmitted.

Let's call reqsk_fastopen_remove() in tcp_disconnect().

[0]:
WARNING: CPU: 2 PID: 0 at net/ipv4/tcp_timer.c:542 tcp_retransmit_timer (net/ipv4/tcp_timer.c:542 (discriminator 7))
Modules linked in:
CPU: 2 UID: 0 PID: 0 Comm: swapper/2 Not tainted 6.17.0-rc5-g201825fb4278 #62 PREEMPT(voluntary)
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
RIP: 0010:tcp_retransmit_timer (net/ipv4/tcp_timer.c:542 (discriminator 7))
Code: 41 55 41 54 55 53 48 8b af b8 08 00 00 48 89 fb 48 85 ed 0f 84 55 01 00 00 0f b6 47 12 3c 03 74 0c 0f b6 47 12 3c 04 74 04 90 <0f> 0b 90 48 8b 85 c0 00 00 00 48 89 ef 48 8b 40 30 e8 6a 4f 06 3e
RSP: 0018:ffffc900002f8d40 EFLAGS: 00010293
RAX: 0000000000000002 RBX: ffff888106911400 RCX: 0000000000000017
RDX: 0000000002517619 RSI: ffffffff83764080 RDI: ffff888106911400
RBP: ffff888106d5c000 R08: 0000000000000001 R09: ffffc900002f8de8
R10: 00000000000000c2 R11: ffffc900002f8ff8 R12: ffff888106911540
R13: ffff888106911480 R14: ffff888106911840 R15: ffffc900002f8de0
FS:  0000000000000000(0000) GS:ffff88907b768000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f8044d69d90 CR3: 0000000002c30003 CR4: 0000000000370ef0
Call Trace:
 <IRQ>
 tcp_write_timer (net/ipv4/tcp_timer.c:738)
 call_timer_fn (kernel/time/timer.c:1747)
 __run_timers (kernel/time/timer.c:1799 kernel/time/timer.c:2372)
 timer_expire_remote (kernel/time/timer.c:2385 kernel/time/timer.c:2376 kernel/time/timer.c:2135)
 tmigr_handle_remote_up (kernel/time/timer_migration.c:944 kernel/time/timer_migration.c:1035)
 __walk_groups.isra.0 (kernel/time/timer_migration.c:533 (discriminator 1))
 tmigr_handle_remote (kernel/time/timer_migration.c:1096)
 handle_softirqs (./arch/x86/include/asm/jump_label.h:36 ./include/trace/events/irq.h:142 kernel/softirq.c:580)
 irq_exit_rcu (kernel/softirq.c:614 kernel/softirq.c:453 kernel/softirq.c:680 kernel/softirq.c:696)
 sysvec_apic_timer_interrupt (arch/x86/kernel/apic/apic.c:1050 (discriminator 35) arch/x86/kernel/apic/apic.c:1050 (discriminator 35))
 </IRQ>

Fixes: 8336886 ("tcp: TCP Fast Open Server - support TFO listeners")
Reported-by: syzkaller <syzkaller@googlegroups.com>
Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com>
Link: https://patch.msgid.link/20250915175800.118793-2-kuniyu@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
dagomez137 pushed a commit that referenced this pull request Dec 29, 2025
vhost_vsock_get() uses hash_for_each_possible_rcu() to find the
`vhost_vsock` associated with the `guest_cid`. hash_for_each_possible_rcu()
should only be called within an RCU read section, as mentioned in the
following comment in include/linux/rculist.h:

/**
 * hlist_for_each_entry_rcu - iterate over rcu list of given type
 * @pos:	the type * to use as a loop cursor.
 * @Head:	the head for your list.
 * @member:	the name of the hlist_node within the struct.
 * @cond:	optional lockdep expression if called from non-RCU protection.
 *
 * This list-traversal primitive may safely run concurrently with
 * the _rcu list-mutation primitives such as hlist_add_head_rcu()
 * as long as the traversal is guarded by rcu_read_lock().
 */

Currently, all calls to vhost_vsock_get() are between rcu_read_lock()
and rcu_read_unlock() except for calls in vhost_vsock_set_cid() and
vhost_vsock_reset_orphans(). In both cases, the current code is safe,
but we can make improvements to make it more robust.

About vhost_vsock_set_cid(), when building the kernel with
CONFIG_PROVE_RCU_LIST enabled, we get the following RCU warning when the
user space issues `ioctl(dev, VHOST_VSOCK_SET_GUEST_CID, ...)` :

  WARNING: suspicious RCU usage
  6.18.0-rc7 #62 Not tainted
  -----------------------------
  drivers/vhost/vsock.c:74 RCU-list traversed in non-reader section!!

  other info that might help us debug this:

  rcu_scheduler_active = 2, debug_locks = 1
  1 lock held by rpc-libvirtd/3443:
   #0: ffffffffc05032a8 (vhost_vsock_mutex){+.+.}-{4:4}, at: vhost_vsock_dev_ioctl+0x2ff/0x530 [vhost_vsock]

  stack backtrace:
  CPU: 2 UID: 0 PID: 3443 Comm: rpc-libvirtd Not tainted 6.18.0-rc7 #62 PREEMPT(none)
  Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.17.0-7.fc42 06/10/2025
  Call Trace:
   <TASK>
   dump_stack_lvl+0x75/0xb0
   dump_stack+0x14/0x1a
   lockdep_rcu_suspicious.cold+0x4e/0x97
   vhost_vsock_get+0x8f/0xa0 [vhost_vsock]
   vhost_vsock_dev_ioctl+0x307/0x530 [vhost_vsock]
   __x64_sys_ioctl+0x4f2/0xa00
   x64_sys_call+0xed0/0x1da0
   do_syscall_64+0x73/0xfa0
   entry_SYSCALL_64_after_hwframe+0x76/0x7e
   ...
   </TASK>

This is not a real problem, because the vhost_vsock_get() caller, i.e.
vhost_vsock_set_cid(), holds the `vhost_vsock_mutex` used by the hash
table writers. Anyway, to prevent that warning, add lockdep_is_held()
condition to hash_for_each_possible_rcu() to verify that either the
caller is in an RCU read section or `vhost_vsock_mutex` is held when
CONFIG_PROVE_RCU_LIST is enabled; and also clarify the comment for
vhost_vsock_get() to better describe the locking requirements and the
scope of the returned pointer validity.

About vhost_vsock_reset_orphans(), currently this function is only
called via vsock_for_each_connected_socket(), which holds the
`vsock_table_lock` spinlock (which is also an RCU read-side critical
section). However, add an explicit RCU read lock there to make the code
more robust and explicit about the RCU requirements, and to prevent
issues if the calling context changes in the future or if
vhost_vsock_reset_orphans() is called from other contexts.

Fixes: 834e772 ("vhost/vsock: fix use-after-free in network stack callers")
Cc: stefanha@redhat.com
Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <20251126133826.142496-1-sgarzare@redhat.com>
Message-ID: <20251126210313.GA499503@fedora>
Acked-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
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