linux-stable.git/net/phonet, branch linux-5.15.y Linux kernel stable tree net: phonet: free phonet_device after RCU grace period 2026-07-04T11:39:41+00:00 Santosh Kalluri santosh.kalluri129@gmail.com 2026-06-17T14:49:18+00:00 6cd7067d6e4b0b2033ba2f918ecbd54dc2af3763 [ Upstream commit 71de0177b28da751f407581a4515cf4d762f6296 ] phonet_device_destroy() removes a phonet_device from the per-net device list with list_del_rcu(), but frees it immediately. RCU readers walking the same list can still hold a pointer to the object after it has been removed, leading to a slab-use-after-free. Use kfree_rcu(), matching the lifetime rule already used by phonet_address_del() for the same object type. Fixes: eeb74a9d45f7 ("Phonet: convert devices list to RCU") Cc: stable@vger.kernel.org Signed-off-by: Santosh Kalluri <santosh.kalluri129@gmail.com> Acked-by: Rémi Denis-Courmont <remi@remlab.net> Reviewed-by: Simon Horman <horms@kernel.org> Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
[ Upstream commit 71de0177b28da751f407581a4515cf4d762f6296 ]

phonet_device_destroy() removes a phonet_device from the per-net device
list with list_del_rcu(), but frees it immediately. RCU readers walking
the same list can still hold a pointer to the object after it has been
removed, leading to a slab-use-after-free.

Use kfree_rcu(), matching the lifetime rule already used by
phonet_address_del() for the same object type.

Fixes: eeb74a9d45f7 ("Phonet: convert devices list to RCU")
Cc: stable@vger.kernel.org
Signed-off-by: Santosh Kalluri <santosh.kalluri129@gmail.com>
Acked-by: Rémi Denis-Courmont <remi@remlab.net>
Reviewed-by: Simon Horman <horms@kernel.org>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
phonet: Pass net and ifindex to phonet_address_notify(). 2026-07-04T11:39:41+00:00 Kuniyuki Iwashima kuniyu@amazon.com 2026-06-17T14:49:17+00:00 53700a63768ca43bd6e3d2798738fcc32f44e21b [ Upstream commit 68ed5c38b512b734caf3da1f87db4a99fcfe3002 ] Currently, phonet_address_notify() fetches netns and ifindex from dev. Once addr_doit() is converted to RCU, phonet_address_notify() will be called outside of RCU due to GFP_KERNEL, and dev will be unavailable there. Let's pass net and ifindex to phonet_address_notify(). Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Paolo Abeni <pabeni@redhat.com> Stable-dep-of: 71de0177b28d ("net: phonet: free phonet_device after RCU grace period") Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
[ Upstream commit 68ed5c38b512b734caf3da1f87db4a99fcfe3002 ]

Currently, phonet_address_notify() fetches netns and ifindex from dev.

Once addr_doit() is converted to RCU, phonet_address_notify() will be
called outside of RCU due to GFP_KERNEL, and dev will be unavailable
there.

Let's pass net and ifindex to phonet_address_notify().

Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Stable-dep-of: 71de0177b28d ("net: phonet: free phonet_device after RCU grace period")
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
phonet: Pass ifindex to fill_addr(). 2026-07-04T11:39:40+00:00 Kuniyuki Iwashima kuniyu@amazon.com 2026-06-17T14:49:16+00:00 5d85eb3e1ce515a79589513fa56d713e77a1e65a [ Upstream commit 08a9572be36819b5d9011604edfa5db6c5062a7a ] We will convert addr_doit() and getaddr_dumpit() to RCU, both of which call fill_addr(). The former will call phonet_address_notify() outside of RCU due to GFP_KERNEL, so dev will not be available in fill_addr(). Let's pass ifindex directly to fill_addr(). Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Paolo Abeni <pabeni@redhat.com> Stable-dep-of: 71de0177b28d ("net: phonet: free phonet_device after RCU grace period") Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
[ Upstream commit 08a9572be36819b5d9011604edfa5db6c5062a7a ]

We will convert addr_doit() and getaddr_dumpit() to RCU, both
of which call fill_addr().

The former will call phonet_address_notify() outside of RCU
due to GFP_KERNEL, so dev will not be available in fill_addr().

Let's pass ifindex directly to fill_addr().

Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Stable-dep-of: 71de0177b28d ("net: phonet: free phonet_device after RCU grace period")
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
phonet/pep: disable BH around forwarded sk_receive_skb() 2026-06-01T15:35:46+00:00 Zijing Yin yzjaurora@gmail.com 2026-05-19T17:26:33+00:00 b2606c302d7f2b4ee48da05e32ed60aed1b0cd53 commit dbc81608e3a653dea6cf403f20cae35468b8ab9c upstream. The networking receive path is usually run from softirq context, but protocols that take the socket lock may have packets stored in the backlog and processed later from process context. In that case release_sock() -> __release_sock() drops the slock with spin_unlock_bh() and then calls sk->sk_backlog_rcv() with bottom halves enabled. Typical sk_backlog_rcv handlers process the socket whose backlog is being drained, so the BH state at entry is irrelevant for the slocks they touch. pep_do_rcv() is different: when the inbound skb targets an existing PEP pipe, it forwards the skb to a different *child* socket via sk_receive_skb(). That helper takes the child slock with bh_lock_sock_nested(), which is just spin_lock_nested() and assumes BH is already off. The same child slock therefore ends up acquired with BH on (process path) and with BH off (softirq path): process context softirq context --------------- --------------- release_sock(listener) __netif_receive_skb() __release_sock() phonet_rcv() spin_unlock_bh() __sk_receive_skb(listener) [BH now ENABLED] [BH already disabled] sk_backlog_rcv: sk_backlog_rcv: pep_do_rcv() pep_do_rcv() sk_receive_skb(child) sk_receive_skb(child) bh_lock_sock_nested(child) bh_lock_sock_nested(child) => SOFTIRQ-ON-W => IN-SOFTIRQ-W Lockdep flags this as inconsistent lock state, and it can become a real self-deadlock if a softirq on the same CPU tries to receive to the same child socket while its slock is held in the BH-enabled path: WARNING: inconsistent lock state inconsistent {SOFTIRQ-ON-W} -> {IN-SOFTIRQ-W} usage. (slock-AF_PHONET/1){+.?.}-{3:3}, at: __sk_receive_skb+0x1cf/0x900 __sk_receive_skb net/core/sock.c:563 sk_receive_skb include/net/sock.h:2022 [inline] pep_do_rcv net/phonet/pep.c:675 sk_backlog_rcv include/net/sock.h:1190 __release_sock net/core/sock.c:3216 release_sock net/core/sock.c:3815 pep_sock_accept net/phonet/pep.c:879 Wrap the forwarded sk_receive_skb() in local_bh_disable() / local_bh_enable() so the child slock is always acquired with BH off. local_bh_disable() nests safely on the softirq path. Discovered via in-house syzkaller fuzzing; the same root cause also on the linux-6.1.y syzbot dashboard as extid 44f0626dd6284f02663c. Reproduced under KASAN + LOCKDEP + PROVE_LOCKING, reproducer: https://pastebin.com/A3t8xzCR Fixes: 9641458d3ec4 ("Phonet: Pipe End Point for Phonet Pipes protocol") Link: https://syzkaller.appspot.com/bug?extid=44f0626dd6284f02663c Cc: stable@vger.kernel.org Signed-off-by: Zijing Yin <yzjaurora@gmail.com> Acked-by: Rémi Denis-Courmont <remi@remlab.net> Reported-by: syzbot+9f4a135646b66c509935@syzkaller.appspotmail.com Reviewed-by: Eric Dumazet <edumazet@google.com> Link: https://patch.msgid.link/20260519172635.86304-1-yzjaurora@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit dbc81608e3a653dea6cf403f20cae35468b8ab9c upstream.

The networking receive path is usually run from softirq context, but
protocols that take the socket lock may have packets stored in the
backlog and processed later from process context. In that case
release_sock() -> __release_sock() drops the slock with spin_unlock_bh()
and then calls sk->sk_backlog_rcv() with bottom halves enabled.

Typical sk_backlog_rcv handlers process the socket whose backlog is
being drained, so the BH state at entry is irrelevant for the slocks
they touch. pep_do_rcv() is different: when the inbound skb targets an
existing PEP pipe, it forwards the skb to a different *child* socket
via sk_receive_skb(). That helper takes the child slock with
bh_lock_sock_nested(), which is just spin_lock_nested() and assumes BH
is already off. The same child slock therefore ends up acquired with
BH on (process path) and with BH off (softirq path):

  process context                   softirq context
  ---------------                   ---------------
  release_sock(listener)            __netif_receive_skb()
   __release_sock()                  phonet_rcv()
    spin_unlock_bh()                  __sk_receive_skb(listener)
    [BH now ENABLED]                  [BH already disabled]
    sk_backlog_rcv:                   sk_backlog_rcv:
     pep_do_rcv()                      pep_do_rcv()
      sk_receive_skb(child)             sk_receive_skb(child)
       bh_lock_sock_nested(child)        bh_lock_sock_nested(child)
       => SOFTIRQ-ON-W                   => IN-SOFTIRQ-W

Lockdep flags this as inconsistent lock state, and it can become a real
self-deadlock if a softirq on the same CPU tries to receive to the same
child socket while its slock is held in the BH-enabled path:

  WARNING: inconsistent lock state
  inconsistent {SOFTIRQ-ON-W} -> {IN-SOFTIRQ-W} usage.
   (slock-AF_PHONET/1){+.?.}-{3:3}, at: __sk_receive_skb+0x1cf/0x900
    __sk_receive_skb              net/core/sock.c:563
    sk_receive_skb                include/net/sock.h:2022 [inline]
    pep_do_rcv                    net/phonet/pep.c:675
    sk_backlog_rcv                include/net/sock.h:1190
    __release_sock                net/core/sock.c:3216
    release_sock                  net/core/sock.c:3815
    pep_sock_accept               net/phonet/pep.c:879

Wrap the forwarded sk_receive_skb() in local_bh_disable() /
local_bh_enable() so the child slock is always acquired with BH off.
local_bh_disable() nests safely on the softirq path.

Discovered via in-house syzkaller fuzzing; the same root cause also
on the linux-6.1.y syzbot dashboard as extid 44f0626dd6284f02663c.
Reproduced under KASAN + LOCKDEP + PROVE_LOCKING, reproducer:
https://pastebin.com/A3t8xzCR

Fixes: 9641458d3ec4 ("Phonet: Pipe End Point for Phonet Pipes protocol")
Link: https://syzkaller.appspot.com/bug?extid=44f0626dd6284f02663c
Cc: stable@vger.kernel.org
Signed-off-by: Zijing Yin <yzjaurora@gmail.com>
Acked-by: Rémi Denis-Courmont <remi@remlab.net>
Reported-by: syzbot+9f4a135646b66c509935@syzkaller.appspotmail.com
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20260519172635.86304-1-yzjaurora@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
phonet/pep: Move call to pn_skb_get_dst_sockaddr() earlier in pep_sock_accept() 2025-08-28T14:23:59+00:00 Nathan Chancellor nathan@kernel.org 2025-07-15T23:15:40+00:00 e98c1dfae40e4f28af67ec9eec734a1e50e3d61e commit 17ba793f381eb813596d6de1cc6820bcbda5ed8b upstream. A new warning in clang [1] points out a place in pep_sock_accept() where dst is uninitialized then passed as a const pointer to pep_find_pipe(): net/phonet/pep.c:829:37: error: variable 'dst' is uninitialized when passed as a const pointer argument here [-Werror,-Wuninitialized-const-pointer] 829 | newsk = pep_find_pipe(&pn->hlist, &dst, pipe_handle); | ^~~: Move the call to pn_skb_get_dst_sockaddr(), which initializes dst, to before the call to pep_find_pipe(), so that dst is consistently used initialized throughout the function. Cc: stable@vger.kernel.org Fixes: f7ae8d59f661 ("Phonet: allocate sock from accept syscall rather than soft IRQ") Link: https://github.com/llvm/llvm-project/commit/00dacf8c22f065cb52efb14cd091d441f19b319e [1] Closes: https://github.com/ClangBuiltLinux/linux/issues/2101 Signed-off-by: Nathan Chancellor <nathan@kernel.org> Link: https://patch.msgid.link/20250715-net-phonet-fix-uninit-const-pointer-v1-1-8efd1bd188b3@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 17ba793f381eb813596d6de1cc6820bcbda5ed8b upstream.

A new warning in clang [1] points out a place in pep_sock_accept() where
dst is uninitialized then passed as a const pointer to pep_find_pipe():

  net/phonet/pep.c:829:37: error: variable 'dst' is uninitialized when passed as a const pointer argument here [-Werror,-Wuninitialized-const-pointer]
    829 |         newsk = pep_find_pipe(&pn->hlist, &dst, pipe_handle);
        |                                            ^~~:

Move the call to pn_skb_get_dst_sockaddr(), which initializes dst, to
before the call to pep_find_pipe(), so that dst is consistently used
initialized throughout the function.

Cc: stable@vger.kernel.org
Fixes: f7ae8d59f661 ("Phonet: allocate sock from accept syscall rather than soft IRQ")
Link: https://github.com/llvm/llvm-project/commit/00dacf8c22f065cb52efb14cd091d441f19b319e [1]
Closes: https://github.com/ClangBuiltLinux/linux/issues/2101
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Link: https://patch.msgid.link/20250715-net-phonet-fix-uninit-const-pointer-v1-1-8efd1bd188b3@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
phonet/pep: fix racy skb_queue_empty() use 2025-05-02T05:44:18+00:00 Rémi Denis-Courmont courmisch@gmail.com 2025-04-14T18:50:20+00:00 7d3914a477eed92b48c493a8631cc4554ab4fd4f [ Upstream commit 7d2a894d7f487dcb894df023e9d3014cf5b93fe5 ] The receive queues are protected by their respective spin-lock, not the socket lock. This could lead to skb_peek() unexpectedly returning NULL or a pointer to an already dequeued socket buffer. Fixes: 9641458d3ec4 ("Phonet: Pipe End Point for Phonet Pipes protocol") Signed-off-by: Rémi Denis-Courmont <courmisch@gmail.com> Link: https://lore.kernel.org/r/20240218081214.4806-2-remi@remlab.net Signed-off-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: Sasha Levin <sashal@kernel.org> [Harshit: backport to 5.15.y, clean cherrypick from 6.1.y commit] Signed-off-by: Harshit Mogalapalli <harshit.m.mogalapalli@oracle.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
[ Upstream commit 7d2a894d7f487dcb894df023e9d3014cf5b93fe5 ]

The receive queues are protected by their respective spin-lock, not
the socket lock. This could lead to skb_peek() unexpectedly
returning NULL or a pointer to an already dequeued socket buffer.

Fixes: 9641458d3ec4 ("Phonet: Pipe End Point for Phonet Pipes protocol")
Signed-off-by: Rémi Denis-Courmont <courmisch@gmail.com>
Link: https://lore.kernel.org/r/20240218081214.4806-2-remi@remlab.net
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[Harshit: backport to 5.15.y, clean cherrypick from 6.1.y commit]
Signed-off-by: Harshit Mogalapalli <harshit.m.mogalapalli@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
phonet: fix rtm_phonet_notify() skb allocation 2024-05-17T09:50:58+00:00 Eric Dumazet edumazet@google.com 2024-05-02T16:17:00+00:00 4ff334cade9dae50e4be387f71e94fae634aa9b4 [ Upstream commit d8cac8568618dcb8a51af3db1103e8d4cc4aeea7 ] fill_route() stores three components in the skb: - struct rtmsg - RTA_DST (u8) - RTA_OIF (u32) Therefore, rtm_phonet_notify() should use NLMSG_ALIGN(sizeof(struct rtmsg)) + nla_total_size(1) + nla_total_size(4) Fixes: f062f41d0657 ("Phonet: routing table Netlink interface") Signed-off-by: Eric Dumazet <edumazet@google.com> Acked-by: Rémi Denis-Courmont <courmisch@gmail.com> Link: https://lore.kernel.org/r/20240502161700.1804476-1-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit d8cac8568618dcb8a51af3db1103e8d4cc4aeea7 ]

fill_route() stores three components in the skb:

- struct rtmsg
- RTA_DST (u8)
- RTA_OIF (u32)

Therefore, rtm_phonet_notify() should use

NLMSG_ALIGN(sizeof(struct rtmsg)) +
nla_total_size(1) +
nla_total_size(4)

Fixes: f062f41d0657 ("Phonet: routing table Netlink interface")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Rémi Denis-Courmont <courmisch@gmail.com>
Link: https://lore.kernel.org/r/20240502161700.1804476-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
phonet: refcount leak in pep_sock_accep 2022-01-11T14:35:16+00:00 Hangyu Hua hbh25y@gmail.com 2021-12-09T08:28:39+00:00 9ca97a693aa8b86e8424f0047198ea3ab997d50f commit bcd0f93353326954817a4f9fa55ec57fb38acbb0 upstream. sock_hold(sk) is invoked in pep_sock_accept(), but __sock_put(sk) is not invoked in subsequent failure branches(pep_accept_conn() != 0). Signed-off-by: Hangyu Hua <hbh25y@gmail.com> Link: https://lore.kernel.org/r/20211209082839.33985-1-hbh25y@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Aayush Agarwal <aayush.a.agarwal@oracle.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit bcd0f93353326954817a4f9fa55ec57fb38acbb0 upstream.

sock_hold(sk) is invoked in pep_sock_accept(), but __sock_put(sk) is not
invoked in subsequent failure branches(pep_accept_conn() != 0).

Signed-off-by: Hangyu Hua <hbh25y@gmail.com>
Link: https://lore.kernel.org/r/20211209082839.33985-1-hbh25y@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Aayush Agarwal <aayush.a.agarwal@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
phonet/pep: refuse to enable an unbound pipe 2021-12-29T11:29:03+00:00 Rémi Denis-Courmont remi@remlab.net 2021-12-19T17:03:39+00:00 53ccdc73eedaf0e922c45b569b797d2796fbaafa commit 75a2f31520095600f650597c0ac41f48b5ba0068 upstream. This ioctl() implicitly assumed that the socket was already bound to a valid local socket name, i.e. Phonet object. If the socket was not bound, two separate problems would occur: 1) We'd send an pipe enablement request with an invalid source object. 2) Later socket calls could BUG on the socket unexpectedly being connected yet not bound to a valid object. Reported-by: syzbot+2dc91e7fc3dea88b1e8a@syzkaller.appspotmail.com Signed-off-by: Rémi Denis-Courmont <remi@remlab.net> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 75a2f31520095600f650597c0ac41f48b5ba0068 upstream.

This ioctl() implicitly assumed that the socket was already bound to
a valid local socket name, i.e. Phonet object. If the socket was not
bound, two separate problems would occur:

1) We'd send an pipe enablement request with an invalid source object.
2) Later socket calls could BUG on the socket unexpectedly being
   connected yet not bound to a valid object.

Reported-by: syzbot+2dc91e7fc3dea88b1e8a@syzkaller.appspotmail.com
Signed-off-by: Rémi Denis-Courmont <remi@remlab.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
net: Remove redundant if statements 2021-08-05T12:27:50+00:00 Yajun Deng yajun.deng@linux.dev 2021-08-05T11:55:27+00:00 1160dfa178eb848327e9dec39960a735f4dc1685 The 'if (dev)' statement already move into dev_{put , hold}, so remove redundant if statements. Signed-off-by: Yajun Deng <yajun.deng@linux.dev> Signed-off-by: David S. Miller <davem@davemloft.net> 
The 'if (dev)' statement already move into dev_{put , hold}, so remove
redundant if statements.

Signed-off-by: Yajun Deng <yajun.deng@linux.dev>
Signed-off-by: David S. Miller <davem@davemloft.net>