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Kernel #2

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Andika-bot opened this issue Dec 5, 2020 · 0 comments
Open

Kernel #2

Andika-bot opened this issue Dec 5, 2020 · 0 comments

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Pierre2324 pushed a commit that referenced this issue Dec 21, 2020
Our static-static calculation returns a failure if the public key is of
low order. We check for this when peers are added, and don't allow them
to be added if they're low order, except in the case where we haven't
yet been given a private key. In that case, we would defer the removal
of the peer until we're given a private key, since at that point we're
doing new static-static calculations which incur failures we can act on.
This meant, however, that we wound up removing peers rather late in the
configuration flow.

Syzkaller points out that peer_remove calls flush_workqueue, which in
turn might then wait for sending a handshake initiation to complete.
Since handshake initiation needs the static identity lock, holding the
static identity lock while calling peer_remove can result in a rare
deadlock. We have precisely this case in this situation of late-stage
peer removal based on an invalid public key. We can't drop the lock when
removing, because then incoming handshakes might interact with a bogus
static-static calculation.

While the band-aid patch for this would involve breaking up the peer
removal into two steps like wg_peer_remove_all does, in order to solve
the locking issue, there's actually a much more elegant way of fixing
this:

If the static-static calculation succeeds with one private key, it
*must* succeed with all others, because all 32-byte strings map to valid
private keys, thanks to clamping. That means we can get rid of this
silly dance and locking headaches of removing peers late in the
configuration flow, and instead just reject them early on, regardless of
whether the device has yet been assigned a private key. For the case
where the device doesn't yet have a private key, we safely use zeros
just for the purposes of checking for low order points by way of
checking the output of the calculation.

The following PoC will trigger the deadlock:

ip link add wg0 type wireguard
ip addr add 10.0.0.1/24 dev wg0
ip link set wg0 up
ping -f 10.0.0.2 &
while true; do
        wg set wg0 private-key /dev/null peer AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA= allowed-ips 10.0.0.0/24 endpoint 10.0.0.3:1234
        wg set wg0 private-key <(echo AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA=)
done

[    0.949105] ======================================================
[    0.949550] WARNING: possible circular locking dependency detected
[    0.950143] 5.5.0-debug+ #18 Not tainted
[    0.950431] ------------------------------------------------------
[    0.950959] wg/89 is trying to acquire lock:
[    0.951252] ffff8880333e2128 ((wq_completion)wg-kex-wg0){+.+.}, at: flush_workqueue+0xe3/0x12f0
[    0.951865]
[    0.951865] but task is already holding lock:
[    0.952280] ffff888032819bc0 (&wg->static_identity.lock){++++}, at: wg_set_device+0x95d/0xcc0
[    0.953011]
[    0.953011] which lock already depends on the new lock.
[    0.953011]
[    0.953651]
[    0.953651] the existing dependency chain (in reverse order) is:
[    0.954292]
[    0.954292] -> #2 (&wg->static_identity.lock){++++}:
[    0.954804]        lock_acquire+0x127/0x350
[    0.955133]        down_read+0x83/0x410
[    0.955428]        wg_noise_handshake_create_initiation+0x97/0x700
[    0.955885]        wg_packet_send_handshake_initiation+0x13a/0x280
[    0.956401]        wg_packet_handshake_send_worker+0x10/0x20
[    0.956841]        process_one_work+0x806/0x1500
[    0.957167]        worker_thread+0x8c/0xcb0
[    0.957549]        kthread+0x2ee/0x3b0
[    0.957792]        ret_from_fork+0x24/0x30
[    0.958234]
[    0.958234] -> #1 ((work_completion)(&peer->transmit_handshake_work)){+.+.}:
[    0.958808]        lock_acquire+0x127/0x350
[    0.959075]        process_one_work+0x7ab/0x1500
[    0.959369]        worker_thread+0x8c/0xcb0
[    0.959639]        kthread+0x2ee/0x3b0
[    0.959896]        ret_from_fork+0x24/0x30
[    0.960346]
[    0.960346] -> #0 ((wq_completion)wg-kex-wg0){+.+.}:
[    0.960945]        check_prev_add+0x167/0x1e20
[    0.961351]        __lock_acquire+0x2012/0x3170
[    0.961725]        lock_acquire+0x127/0x350
[    0.961990]        flush_workqueue+0x106/0x12f0
[    0.962280]        peer_remove_after_dead+0x160/0x220
[    0.962600]        wg_set_device+0xa24/0xcc0
[    0.962994]        genl_rcv_msg+0x52f/0xe90
[    0.963298]        netlink_rcv_skb+0x111/0x320
[    0.963618]        genl_rcv+0x1f/0x30
[    0.963853]        netlink_unicast+0x3f6/0x610
[    0.964245]        netlink_sendmsg+0x700/0xb80
[    0.964586]        __sys_sendto+0x1dd/0x2c0
[    0.964854]        __x64_sys_sendto+0xd8/0x1b0
[    0.965141]        do_syscall_64+0x90/0xd9a
[    0.965408]        entry_SYSCALL_64_after_hwframe+0x49/0xbe
[    0.965769]
[    0.965769] other info that might help us debug this:
[    0.965769]
[    0.966337] Chain exists of:
[    0.966337]   (wq_completion)wg-kex-wg0 --> (work_completion)(&peer->transmit_handshake_work) --> &wg->static_identity.lock
[    0.966337]
[    0.967417]  Possible unsafe locking scenario:
[    0.967417]
[    0.967836]        CPU0                    CPU1
[    0.968155]        ----                    ----
[    0.968497]   lock(&wg->static_identity.lock);
[    0.968779]                                lock((work_completion)(&peer->transmit_handshake_work));
[    0.969345]                                lock(&wg->static_identity.lock);
[    0.969809]   lock((wq_completion)wg-kex-wg0);
[    0.970146]
[    0.970146]  *** DEADLOCK ***
[    0.970146]
[    0.970531] 5 locks held by wg/89:
[    0.970908]  #0: ffffffff827433c8 (cb_lock){++++}, at: genl_rcv+0x10/0x30
[    0.971400]  #1: ffffffff82743480 (genl_mutex){+.+.}, at: genl_rcv_msg+0x642/0xe90
[    0.971924]  #2: ffffffff827160c0 (rtnl_mutex){+.+.}, at: wg_set_device+0x9f/0xcc0
[    0.972488]  #3: ffff888032819de0 (&wg->device_update_lock){+.+.}, at: wg_set_device+0xb0/0xcc0
[    0.973095]  #4: ffff888032819bc0 (&wg->static_identity.lock){++++}, at: wg_set_device+0x95d/0xcc0
[    0.973653]
[    0.973653] stack backtrace:
[    0.973932] CPU: 1 PID: 89 Comm: wg Not tainted 5.5.0-debug+ #18
[    0.974476] Call Trace:
[    0.974638]  dump_stack+0x97/0xe0
[    0.974869]  check_noncircular+0x312/0x3e0
[    0.975132]  ? print_circular_bug+0x1f0/0x1f0
[    0.975410]  ? __kernel_text_address+0x9/0x30
[    0.975727]  ? unwind_get_return_address+0x51/0x90
[    0.976024]  check_prev_add+0x167/0x1e20
[    0.976367]  ? graph_lock+0x70/0x160
[    0.976682]  __lock_acquire+0x2012/0x3170
[    0.976998]  ? register_lock_class+0x1140/0x1140
[    0.977323]  lock_acquire+0x127/0x350
[    0.977627]  ? flush_workqueue+0xe3/0x12f0
[    0.977890]  flush_workqueue+0x106/0x12f0
[    0.978147]  ? flush_workqueue+0xe3/0x12f0
[    0.978410]  ? find_held_lock+0x2c/0x110
[    0.978662]  ? lock_downgrade+0x6e0/0x6e0
[    0.978919]  ? queue_rcu_work+0x60/0x60
[    0.979166]  ? netif_napi_del+0x151/0x3b0
[    0.979501]  ? peer_remove_after_dead+0x160/0x220
[    0.979871]  peer_remove_after_dead+0x160/0x220
[    0.980232]  wg_set_device+0xa24/0xcc0
[    0.980516]  ? deref_stack_reg+0x8e/0xc0
[    0.980801]  ? set_peer+0xe10/0xe10
[    0.981040]  ? __ww_mutex_check_waiters+0x150/0x150
[    0.981430]  ? __nla_validate_parse+0x163/0x270
[    0.981719]  ? genl_family_rcv_msg_attrs_parse+0x13f/0x310
[    0.982078]  genl_rcv_msg+0x52f/0xe90
[    0.982348]  ? genl_family_rcv_msg_attrs_parse+0x310/0x310
[    0.982690]  ? register_lock_class+0x1140/0x1140
[    0.983049]  netlink_rcv_skb+0x111/0x320
[    0.983298]  ? genl_family_rcv_msg_attrs_parse+0x310/0x310
[    0.983645]  ? netlink_ack+0x880/0x880
[    0.983888]  genl_rcv+0x1f/0x30
[    0.984168]  netlink_unicast+0x3f6/0x610
[    0.984443]  ? netlink_detachskb+0x60/0x60
[    0.984729]  ? find_held_lock+0x2c/0x110
[    0.984976]  netlink_sendmsg+0x700/0xb80
[    0.985220]  ? netlink_broadcast_filtered+0xa60/0xa60
[    0.985533]  __sys_sendto+0x1dd/0x2c0
[    0.985763]  ? __x64_sys_getpeername+0xb0/0xb0
[    0.986039]  ? sockfd_lookup_light+0x17/0x160
[    0.986397]  ? __sys_recvmsg+0x8c/0xf0
[    0.986711]  ? __sys_recvmsg_sock+0xd0/0xd0
[    0.987018]  __x64_sys_sendto+0xd8/0x1b0
[    0.987283]  ? lockdep_hardirqs_on+0x39b/0x5a0
[    0.987666]  do_syscall_64+0x90/0xd9a
[    0.987903]  entry_SYSCALL_64_after_hwframe+0x49/0xbe
[    0.988223] RIP: 0033:0x7fe77c12003e
[    0.988508] Code: c3 8b 07 85 c0 75 24 49 89 fb 48 89 f0 48 89 d7 48 89 ce 4c 89 c2 4d 89 ca 4c 8b 44 24 08 4c 8b 4c 24 10 4c 4
[    0.989666] RSP: 002b:00007fffada2ed58 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
[    0.990137] RAX: ffffffffffffffda RBX: 00007fe77c159d48 RCX: 00007fe77c12003e
[    0.990583] RDX: 0000000000000040 RSI: 000055fd1d38e020 RDI: 0000000000000004
[    0.991091] RBP: 000055fd1d38e020 R08: 000055fd1cb63358 R09: 000000000000000c
[    0.991568] R10: 0000000000000000 R11: 0000000000000246 R12: 000000000000002c
[    0.992014] R13: 0000000000000004 R14: 000055fd1d38e020 R15: 0000000000000001

Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
(cherry picked from commit ec31c2676a10e064878927b243fada8c2fb0c03c)
Bug: 152722841
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
Change-Id: I860bfac72c98c8c9b26f4490b4f346dc67892f87
Pierre2324 pushed a commit that referenced this issue Feb 28, 2021
Our static-static calculation returns a failure if the public key is of
low order. We check for this when peers are added, and don't allow them
to be added if they're low order, except in the case where we haven't
yet been given a private key. In that case, we would defer the removal
of the peer until we're given a private key, since at that point we're
doing new static-static calculations which incur failures we can act on.
This meant, however, that we wound up removing peers rather late in the
configuration flow.

Syzkaller points out that peer_remove calls flush_workqueue, which in
turn might then wait for sending a handshake initiation to complete.
Since handshake initiation needs the static identity lock, holding the
static identity lock while calling peer_remove can result in a rare
deadlock. We have precisely this case in this situation of late-stage
peer removal based on an invalid public key. We can't drop the lock when
removing, because then incoming handshakes might interact with a bogus
static-static calculation.

While the band-aid patch for this would involve breaking up the peer
removal into two steps like wg_peer_remove_all does, in order to solve
the locking issue, there's actually a much more elegant way of fixing
this:

If the static-static calculation succeeds with one private key, it
*must* succeed with all others, because all 32-byte strings map to valid
private keys, thanks to clamping. That means we can get rid of this
silly dance and locking headaches of removing peers late in the
configuration flow, and instead just reject them early on, regardless of
whether the device has yet been assigned a private key. For the case
where the device doesn't yet have a private key, we safely use zeros
just for the purposes of checking for low order points by way of
checking the output of the calculation.

The following PoC will trigger the deadlock:

ip link add wg0 type wireguard
ip addr add 10.0.0.1/24 dev wg0
ip link set wg0 up
ping -f 10.0.0.2 &
while true; do
        wg set wg0 private-key /dev/null peer AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA= allowed-ips 10.0.0.0/24 endpoint 10.0.0.3:1234
        wg set wg0 private-key <(echo AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA=)
done

[    0.949105] ======================================================
[    0.949550] WARNING: possible circular locking dependency detected
[    0.950143] 5.5.0-debug+ #18 Not tainted
[    0.950431] ------------------------------------------------------
[    0.950959] wg/89 is trying to acquire lock:
[    0.951252] ffff8880333e2128 ((wq_completion)wg-kex-wg0){+.+.}, at: flush_workqueue+0xe3/0x12f0
[    0.951865]
[    0.951865] but task is already holding lock:
[    0.952280] ffff888032819bc0 (&wg->static_identity.lock){++++}, at: wg_set_device+0x95d/0xcc0
[    0.953011]
[    0.953011] which lock already depends on the new lock.
[    0.953011]
[    0.953651]
[    0.953651] the existing dependency chain (in reverse order) is:
[    0.954292]
[    0.954292] -> #2 (&wg->static_identity.lock){++++}:
[    0.954804]        lock_acquire+0x127/0x350
[    0.955133]        down_read+0x83/0x410
[    0.955428]        wg_noise_handshake_create_initiation+0x97/0x700
[    0.955885]        wg_packet_send_handshake_initiation+0x13a/0x280
[    0.956401]        wg_packet_handshake_send_worker+0x10/0x20
[    0.956841]        process_one_work+0x806/0x1500
[    0.957167]        worker_thread+0x8c/0xcb0
[    0.957549]        kthread+0x2ee/0x3b0
[    0.957792]        ret_from_fork+0x24/0x30
[    0.958234]
[    0.958234] -> #1 ((work_completion)(&peer->transmit_handshake_work)){+.+.}:
[    0.958808]        lock_acquire+0x127/0x350
[    0.959075]        process_one_work+0x7ab/0x1500
[    0.959369]        worker_thread+0x8c/0xcb0
[    0.959639]        kthread+0x2ee/0x3b0
[    0.959896]        ret_from_fork+0x24/0x30
[    0.960346]
[    0.960346] -> #0 ((wq_completion)wg-kex-wg0){+.+.}:
[    0.960945]        check_prev_add+0x167/0x1e20
[    0.961351]        __lock_acquire+0x2012/0x3170
[    0.961725]        lock_acquire+0x127/0x350
[    0.961990]        flush_workqueue+0x106/0x12f0
[    0.962280]        peer_remove_after_dead+0x160/0x220
[    0.962600]        wg_set_device+0xa24/0xcc0
[    0.962994]        genl_rcv_msg+0x52f/0xe90
[    0.963298]        netlink_rcv_skb+0x111/0x320
[    0.963618]        genl_rcv+0x1f/0x30
[    0.963853]        netlink_unicast+0x3f6/0x610
[    0.964245]        netlink_sendmsg+0x700/0xb80
[    0.964586]        __sys_sendto+0x1dd/0x2c0
[    0.964854]        __x64_sys_sendto+0xd8/0x1b0
[    0.965141]        do_syscall_64+0x90/0xd9a
[    0.965408]        entry_SYSCALL_64_after_hwframe+0x49/0xbe
[    0.965769]
[    0.965769] other info that might help us debug this:
[    0.965769]
[    0.966337] Chain exists of:
[    0.966337]   (wq_completion)wg-kex-wg0 --> (work_completion)(&peer->transmit_handshake_work) --> &wg->static_identity.lock
[    0.966337]
[    0.967417]  Possible unsafe locking scenario:
[    0.967417]
[    0.967836]        CPU0                    CPU1
[    0.968155]        ----                    ----
[    0.968497]   lock(&wg->static_identity.lock);
[    0.968779]                                lock((work_completion)(&peer->transmit_handshake_work));
[    0.969345]                                lock(&wg->static_identity.lock);
[    0.969809]   lock((wq_completion)wg-kex-wg0);
[    0.970146]
[    0.970146]  *** DEADLOCK ***
[    0.970146]
[    0.970531] 5 locks held by wg/89:
[    0.970908]  #0: ffffffff827433c8 (cb_lock){++++}, at: genl_rcv+0x10/0x30
[    0.971400]  #1: ffffffff82743480 (genl_mutex){+.+.}, at: genl_rcv_msg+0x642/0xe90
[    0.971924]  #2: ffffffff827160c0 (rtnl_mutex){+.+.}, at: wg_set_device+0x9f/0xcc0
[    0.972488]  #3: ffff888032819de0 (&wg->device_update_lock){+.+.}, at: wg_set_device+0xb0/0xcc0
[    0.973095]  #4: ffff888032819bc0 (&wg->static_identity.lock){++++}, at: wg_set_device+0x95d/0xcc0
[    0.973653]
[    0.973653] stack backtrace:
[    0.973932] CPU: 1 PID: 89 Comm: wg Not tainted 5.5.0-debug+ #18
[    0.974476] Call Trace:
[    0.974638]  dump_stack+0x97/0xe0
[    0.974869]  check_noncircular+0x312/0x3e0
[    0.975132]  ? print_circular_bug+0x1f0/0x1f0
[    0.975410]  ? __kernel_text_address+0x9/0x30
[    0.975727]  ? unwind_get_return_address+0x51/0x90
[    0.976024]  check_prev_add+0x167/0x1e20
[    0.976367]  ? graph_lock+0x70/0x160
[    0.976682]  __lock_acquire+0x2012/0x3170
[    0.976998]  ? register_lock_class+0x1140/0x1140
[    0.977323]  lock_acquire+0x127/0x350
[    0.977627]  ? flush_workqueue+0xe3/0x12f0
[    0.977890]  flush_workqueue+0x106/0x12f0
[    0.978147]  ? flush_workqueue+0xe3/0x12f0
[    0.978410]  ? find_held_lock+0x2c/0x110
[    0.978662]  ? lock_downgrade+0x6e0/0x6e0
[    0.978919]  ? queue_rcu_work+0x60/0x60
[    0.979166]  ? netif_napi_del+0x151/0x3b0
[    0.979501]  ? peer_remove_after_dead+0x160/0x220
[    0.979871]  peer_remove_after_dead+0x160/0x220
[    0.980232]  wg_set_device+0xa24/0xcc0
[    0.980516]  ? deref_stack_reg+0x8e/0xc0
[    0.980801]  ? set_peer+0xe10/0xe10
[    0.981040]  ? __ww_mutex_check_waiters+0x150/0x150
[    0.981430]  ? __nla_validate_parse+0x163/0x270
[    0.981719]  ? genl_family_rcv_msg_attrs_parse+0x13f/0x310
[    0.982078]  genl_rcv_msg+0x52f/0xe90
[    0.982348]  ? genl_family_rcv_msg_attrs_parse+0x310/0x310
[    0.982690]  ? register_lock_class+0x1140/0x1140
[    0.983049]  netlink_rcv_skb+0x111/0x320
[    0.983298]  ? genl_family_rcv_msg_attrs_parse+0x310/0x310
[    0.983645]  ? netlink_ack+0x880/0x880
[    0.983888]  genl_rcv+0x1f/0x30
[    0.984168]  netlink_unicast+0x3f6/0x610
[    0.984443]  ? netlink_detachskb+0x60/0x60
[    0.984729]  ? find_held_lock+0x2c/0x110
[    0.984976]  netlink_sendmsg+0x700/0xb80
[    0.985220]  ? netlink_broadcast_filtered+0xa60/0xa60
[    0.985533]  __sys_sendto+0x1dd/0x2c0
[    0.985763]  ? __x64_sys_getpeername+0xb0/0xb0
[    0.986039]  ? sockfd_lookup_light+0x17/0x160
[    0.986397]  ? __sys_recvmsg+0x8c/0xf0
[    0.986711]  ? __sys_recvmsg_sock+0xd0/0xd0
[    0.987018]  __x64_sys_sendto+0xd8/0x1b0
[    0.987283]  ? lockdep_hardirqs_on+0x39b/0x5a0
[    0.987666]  do_syscall_64+0x90/0xd9a
[    0.987903]  entry_SYSCALL_64_after_hwframe+0x49/0xbe
[    0.988223] RIP: 0033:0x7fe77c12003e
[    0.988508] Code: c3 8b 07 85 c0 75 24 49 89 fb 48 89 f0 48 89 d7 48 89 ce 4c 89 c2 4d 89 ca 4c 8b 44 24 08 4c 8b 4c 24 10 4c 4
[    0.989666] RSP: 002b:00007fffada2ed58 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
[    0.990137] RAX: ffffffffffffffda RBX: 00007fe77c159d48 RCX: 00007fe77c12003e
[    0.990583] RDX: 0000000000000040 RSI: 000055fd1d38e020 RDI: 0000000000000004
[    0.991091] RBP: 000055fd1d38e020 R08: 000055fd1cb63358 R09: 000000000000000c
[    0.991568] R10: 0000000000000000 R11: 0000000000000246 R12: 000000000000002c
[    0.992014] R13: 0000000000000004 R14: 000055fd1d38e020 R15: 0000000000000001

Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
(cherry picked from commit ec31c2676a10e064878927b243fada8c2fb0c03c)
Bug: 152722841
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
Change-Id: I860bfac72c98c8c9b26f4490b4f346dc67892f87
Pierre2324 pushed a commit that referenced this issue Dec 26, 2021
[ Upstream commit 2d3a8e2deddea6c89961c422ec0c5b851e648c14 ]

In blkdev_get() we call __blkdev_get() to do some internal jobs and if
there is some errors in __blkdev_get(), the bdput() is called which
means we have released the refcount of the bdev (actually the refcount of
the bdev inode). This means we cannot access bdev after that point. But
acctually bdev is still accessed in blkdev_get() after calling
__blkdev_get(). This results in use-after-free if the refcount is the
last one we released in __blkdev_get(). Let's take a look at the
following scenerio:

  CPU0            CPU1                    CPU2
blkdev_open     blkdev_open           Remove disk
                  bd_acquire
		  blkdev_get
		    __blkdev_get      del_gendisk
					bdev_unhash_inode
  bd_acquire          bdev_get_gendisk
    bd_forget           failed because of unhashed
	  bdput
	              bdput (the last one)
		        bdev_evict_inode

	  	    access bdev => use after free

[  459.350216] BUG: KASAN: use-after-free in __lock_acquire+0x24c1/0x31b0
[  459.351190] Read of size 8 at addr ffff88806c815a80 by task syz-executor.0/20132
[  459.352347]
[  459.352594] CPU: 0 PID: 20132 Comm: syz-executor.0 Not tainted 4.19.90 #2
[  459.353628] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1ubuntu1 04/01/2014
[  459.354947] Call Trace:
[  459.355337]  dump_stack+0x111/0x19e
[  459.355879]  ? __lock_acquire+0x24c1/0x31b0
[  459.356523]  print_address_description+0x60/0x223
[  459.357248]  ? __lock_acquire+0x24c1/0x31b0
[  459.357887]  kasan_report.cold+0xae/0x2d8
[  459.358503]  __lock_acquire+0x24c1/0x31b0
[  459.359120]  ? _raw_spin_unlock_irq+0x24/0x40
[  459.359784]  ? lockdep_hardirqs_on+0x37b/0x580
[  459.360465]  ? _raw_spin_unlock_irq+0x24/0x40
[  459.361123]  ? finish_task_switch+0x125/0x600
[  459.361812]  ? finish_task_switch+0xee/0x600
[  459.362471]  ? mark_held_locks+0xf0/0xf0
[  459.363108]  ? __schedule+0x96f/0x21d0
[  459.363716]  lock_acquire+0x111/0x320
[  459.364285]  ? blkdev_get+0xce/0xbe0
[  459.364846]  ? blkdev_get+0xce/0xbe0
[  459.365390]  __mutex_lock+0xf9/0x12a0
[  459.365948]  ? blkdev_get+0xce/0xbe0
[  459.366493]  ? bdev_evict_inode+0x1f0/0x1f0
[  459.367130]  ? blkdev_get+0xce/0xbe0
[  459.367678]  ? destroy_inode+0xbc/0x110
[  459.368261]  ? mutex_trylock+0x1a0/0x1a0
[  459.368867]  ? __blkdev_get+0x3e6/0x1280
[  459.369463]  ? bdev_disk_changed+0x1d0/0x1d0
[  459.370114]  ? blkdev_get+0xce/0xbe0
[  459.370656]  blkdev_get+0xce/0xbe0
[  459.371178]  ? find_held_lock+0x2c/0x110
[  459.371774]  ? __blkdev_get+0x1280/0x1280
[  459.372383]  ? lock_downgrade+0x680/0x680
[  459.373002]  ? lock_acquire+0x111/0x320
[  459.373587]  ? bd_acquire+0x21/0x2c0
[  459.374134]  ? do_raw_spin_unlock+0x4f/0x250
[  459.374780]  blkdev_open+0x202/0x290
[  459.375325]  do_dentry_open+0x49e/0x1050
[  459.375924]  ? blkdev_get_by_dev+0x70/0x70
[  459.376543]  ? __x64_sys_fchdir+0x1f0/0x1f0
[  459.377192]  ? inode_permission+0xbe/0x3a0
[  459.377818]  path_openat+0x148c/0x3f50
[  459.378392]  ? kmem_cache_alloc+0xd5/0x280
[  459.379016]  ? entry_SYSCALL_64_after_hwframe+0x49/0xbe
[  459.379802]  ? path_lookupat.isra.0+0x900/0x900
[  459.380489]  ? __lock_is_held+0xad/0x140
[  459.381093]  do_filp_open+0x1a1/0x280
[  459.381654]  ? may_open_dev+0xf0/0xf0
[  459.382214]  ? find_held_lock+0x2c/0x110
[  459.382816]  ? lock_downgrade+0x680/0x680
[  459.383425]  ? __lock_is_held+0xad/0x140
[  459.384024]  ? do_raw_spin_unlock+0x4f/0x250
[  459.384668]  ? _raw_spin_unlock+0x1f/0x30
[  459.385280]  ? __alloc_fd+0x448/0x560
[  459.385841]  do_sys_open+0x3c3/0x500
[  459.386386]  ? filp_open+0x70/0x70
[  459.386911]  ? trace_hardirqs_on_thunk+0x1a/0x1c
[  459.387610]  ? trace_hardirqs_off_caller+0x55/0x1c0
[  459.388342]  ? do_syscall_64+0x1a/0x520
[  459.388930]  do_syscall_64+0xc3/0x520
[  459.389490]  entry_SYSCALL_64_after_hwframe+0x49/0xbe
[  459.390248] RIP: 0033:0x416211
[  459.390720] Code: 75 14 b8 02 00 00 00 0f 05 48 3d 01 f0 ff ff 0f 83
04 19 00 00 c3 48 83 ec 08 e8 0a fa ff ff 48 89 04 24 b8 02 00 00 00 0f
   05 <48> 8b 3c 24 48 89 c2 e8 53 fa ff ff 48 89 d0 48 83 c4 08 48 3d
      01
[  459.393483] RSP: 002b:00007fe45dfe9a60 EFLAGS: 00000293 ORIG_RAX: 0000000000000002
[  459.394610] RAX: ffffffffffffffda RBX: 00007fe45dfea6d4 RCX: 0000000000416211
[  459.395678] RDX: 00007fe45dfe9b0a RSI: 0000000000000002 RDI: 00007fe45dfe9b00
[  459.396758] RBP: 000000000076bf20 R08: 0000000000000000 R09: 000000000000000a
[  459.397930] R10: 0000000000000075 R11: 0000000000000293 R12: 00000000ffffffff
[  459.399022] R13: 0000000000000bd9 R14: 00000000004cdb80 R15: 000000000076bf2c
[  459.400168]
[  459.400430] Allocated by task 20132:
[  459.401038]  kasan_kmalloc+0xbf/0xe0
[  459.401652]  kmem_cache_alloc+0xd5/0x280
[  459.402330]  bdev_alloc_inode+0x18/0x40
[  459.402970]  alloc_inode+0x5f/0x180
[  459.403510]  iget5_locked+0x57/0xd0
[  459.404095]  bdget+0x94/0x4e0
[  459.404607]  bd_acquire+0xfa/0x2c0
[  459.405113]  blkdev_open+0x110/0x290
[  459.405702]  do_dentry_open+0x49e/0x1050
[  459.406340]  path_openat+0x148c/0x3f50
[  459.406926]  do_filp_open+0x1a1/0x280
[  459.407471]  do_sys_open+0x3c3/0x500
[  459.408010]  do_syscall_64+0xc3/0x520
[  459.408572]  entry_SYSCALL_64_after_hwframe+0x49/0xbe
[  459.409415]
[  459.409679] Freed by task 1262:
[  459.410212]  __kasan_slab_free+0x129/0x170
[  459.410919]  kmem_cache_free+0xb2/0x2a0
[  459.411564]  rcu_process_callbacks+0xbb2/0x2320
[  459.412318]  __do_softirq+0x225/0x8ac

Fix this by delaying bdput() to the end of blkdev_get() which means we
have finished accessing bdev.

Fixes: 77ea887 ("implement in-kernel gendisk events handling")
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Jason Yan <yanaijie@huawei.com>
Tested-by: Sedat Dilek <sedat.dilek@gmail.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dan Carpenter <dan.carpenter@oracle.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Ming Lei <ming.lei@redhat.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Change-Id: Id60ab5ab4871856d3ed2570a13912253932558c5
Git-commit: 49289b1fa5a67011c4010e4e9c801b9d565ce395
Git-repo: https://android.googlesource.com/kernel/msm
Signed-off-by: urevanth <urevanth@codeaurora.org>
Pierre2324 pushed a commit that referenced this issue Feb 12, 2022
… devices

commit 8c9db6679be4348b8aae108e11d4be2f83976e30 upstream.

Suppose we have an environment with a number of non-NPIV FCP devices
(virtual HBAs / FCP devices / zfcp "adapter"s) sharing the same physical
FCP channel (HBA port) and its I_T nexus. Plus a number of storage target
ports zoned to such shared channel. Now one target port logs out of the
fabric causing an RSCN. Zfcp reacts with an ADISC ELS and subsequent port
recovery depending on the ADISC result. This happens on all such FCP
devices (in different Linux images) concurrently as they all receive a copy
of this RSCN. In the following we look at one of those FCP devices.

Requests other than FSF_QTCB_FCP_CMND can be slow until they get a
response.

Depending on which requests are affected by slow responses, there are
different recovery outcomes. Here we want to fix failed recoveries on port
or adapter level by avoiding recovery requests that can be slow.

We need the cached N_Port_ID for the remote port "link" test with ADISC.
Just before sending the ADISC, we now intentionally forget the old cached
N_Port_ID. The idea is that on receiving an RSCN for a port, we have to
assume that any cached information about this port is stale.  This forces a
fresh new GID_PN [FC-GS] nameserver lookup on any subsequent recovery for
the same port. Since we typically can still communicate with the nameserver
efficiently, we now reach steady state quicker: Either the nameserver still
does not know about the port so we stop recovery, or the nameserver already
knows the port potentially with a new N_Port_ID and we can successfully and
quickly perform open port recovery.  For the one case, where ADISC returns
successfully, we re-initialize port->d_id because that case does not
involve any port recovery.

This also solves a problem if the storage WWPN quickly logs into the fabric
again but with a different N_Port_ID. Such as on virtual WWPN takeover
during target NPIV failover.
[https://www.redbooks.ibm.com/abstracts/redp5477.html] In that case the
RSCN from the storage FDISC was ignored by zfcp and we could not
successfully recover the failover. On some later failback on the storage,
we could have been lucky if the virtual WWPN got the same old N_Port_ID
from the SAN switch as we still had cached.  Then the related RSCN
triggered a successful port reopen recovery.  However, there is no
guarantee to get the same N_Port_ID on NPIV FDISC.

Even though NPIV-enabled FCP devices are not affected by this problem, this
code change optimizes recovery time for gone remote ports as a side effect.
The timely drop of cached N_Port_IDs prevents unnecessary slow open port
attempts.

While the problem might have been in code before v2.6.32 commit
799b76d ("[SCSI] zfcp: Decouple gid_pn requests from erp") this fix
depends on the gid_pn_work introduced with that commit, so we mark it as
culprit to satisfy fix dependencies.

Note: Point-to-point remote port is already handled separately and gets its
N_Port_ID from the cached peer_d_id. So resetting port->d_id in general
does not affect PtP.

Link: https://lore.kernel.org/r/20220118165803.3667947-1-maier@linux.ibm.com
Fixes: 799b76d ("[SCSI] zfcp: Decouple gid_pn requests from erp")
Cc: <stable@vger.kernel.org> #2.6.32+
Suggested-by: Benjamin Block <bblock@linux.ibm.com>
Reviewed-by: Benjamin Block <bblock@linux.ibm.com>
Signed-off-by: Steffen Maier <maier@linux.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Pierre2324 pushed a commit that referenced this issue Jan 23, 2023
[ Upstream commit f9574cd48679926e2a569e1957a5a1bcc8a719ac ]

Patch series "rapidio: fix three possible memory leaks".

This patchset fixes three name leaks in error handling.
 - patch #1 fixes two name leaks while rio_add_device() fails.
 - patch #2 fixes a name leak while  rio_register_mport() fails.

This patch (of 2):

If rio_add_device() returns error, the name allocated by dev_set_name()
need be freed.  It should use put_device() to give up the reference in the
error path, so that the name can be freed in kobject_cleanup(), and the
'rdev' can be freed in rio_release_dev().

Link: https://lkml.kernel.org/r/20221114152636.2939035-1-yangyingliang@huawei.com
Link: https://lkml.kernel.org/r/20221114152636.2939035-2-yangyingliang@huawei.com
Fixes: e8de370 ("rapidio: add mport char device driver")
Fixes: 1fa5ae8 ("driver core: get rid of struct device's bus_id string array")
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Cc: Alexandre Bounine <alex.bou9@gmail.com>
Cc: Matt Porter <mporter@kernel.crashing.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Pierre2324 pushed a commit that referenced this issue Jan 23, 2023
…g the sock

[ Upstream commit 3cf7203ca620682165706f70a1b12b5194607dce ]

There is a race condition in vxlan that when deleting a vxlan device
during receiving packets, there is a possibility that the sock is
released after getting vxlan_sock vs from sk_user_data. Then in
later vxlan_ecn_decapsulate(), vxlan_get_sk_family() we will got
NULL pointer dereference. e.g.

   #0 [ffffa25ec6978a38] machine_kexec at ffffffff8c669757
   #1 [ffffa25ec6978a90] __crash_kexec at ffffffff8c7c0a4d
   #2 [ffffa25ec6978b58] crash_kexec at ffffffff8c7c1c48
   #3 [ffffa25ec6978b60] oops_end at ffffffff8c627f2b
   #4 [ffffa25ec6978b80] page_fault_oops at ffffffff8c678fcb
   #5 [ffffa25ec6978bd8] exc_page_fault at ffffffff8d109542
   #6 [ffffa25ec6978c00] asm_exc_page_fault at ffffffff8d200b62
      [exception RIP: vxlan_ecn_decapsulate+0x3b]
      RIP: ffffffffc1014e7b  RSP: ffffa25ec6978cb0  RFLAGS: 00010246
      RAX: 0000000000000008  RBX: ffff8aa000888000  RCX: 0000000000000000
      RDX: 000000000000000e  RSI: ffff8a9fc7ab803e  RDI: ffff8a9fd1168700
      RBP: ffff8a9fc7ab803e   R8: 0000000000700000   R9: 00000000000010ae
      R10: ffff8a9fcb748980  R11: 0000000000000000  R12: ffff8a9fd1168700
      R13: ffff8aa000888000  R14: 00000000002a0000  R15: 00000000000010ae
      ORIG_RAX: ffffffffffffffff  CS: 0010  SS: 0018
   #7 [ffffa25ec6978ce8] vxlan_rcv at ffffffffc10189cd [vxlan]
   #8 [ffffa25ec6978d90] udp_queue_rcv_one_skb at ffffffff8cfb6507
   #9 [ffffa25ec6978dc0] udp_unicast_rcv_skb at ffffffff8cfb6e45
  #10 [ffffa25ec6978dc8] __udp4_lib_rcv at ffffffff8cfb8807
  #11 [ffffa25ec6978e20] ip_protocol_deliver_rcu at ffffffff8cf76951
  #12 [ffffa25ec6978e48] ip_local_deliver at ffffffff8cf76bde
  #13 [ffffa25ec6978ea0] __netif_receive_skb_one_core at ffffffff8cecde9b
  #14 [ffffa25ec6978ec8] process_backlog at ffffffff8cece139
  #15 [ffffa25ec6978f00] __napi_poll at ffffffff8ceced1a
  #16 [ffffa25ec6978f28] net_rx_action at ffffffff8cecf1f3
  #17 [ffffa25ec6978fa0] __softirqentry_text_start at ffffffff8d4000ca
  #18 [ffffa25ec6978ff0] do_softirq at ffffffff8c6fbdc3

Reproducer: https://github.com/Mellanox/ovs-tests/blob/master/test-ovs-vxlan-remove-tunnel-during-traffic.sh

Fix this by waiting for all sk_user_data reader to finish before
releasing the sock.

Reported-by: Jianlin Shi <jishi@redhat.com>
Suggested-by: Jakub Sitnicki <jakub@cloudflare.com>
Fixes: 6a93cc9 ("udp-tunnel: Add a few more UDP tunnel APIs")
Signed-off-by: Hangbin Liu <liuhangbin@gmail.com>
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
haikaru17 pushed a commit to haikaru17/NGK_android_kernel_xiaomi_sdm845 that referenced this issue Jul 10, 2024
qos requirement is not inited when update is called.

[   12.682308] msm_pm_qos_update_request: update request 100
[   12.682315] ------------[ cut here ]------------
[   12.682335] WARNING: at /home/cocafe/android/kernel/cocore-x/kernel/kernel/power/qos.c:570 pm_qos_update_request+0x1d0/0x2c8()
[   12.682342] pm_qos_update_request() called for unknown object
[   12.682350] Modules linked in: wlan fm_drv brcm_bt_drv brcm_hci_ldisc kscl ecryptfs
[   12.682371] CPU: 3 PID: 1311 Comm: cammw:sensor Tainted: G        W    3.10.84-cocore-x-g184e4f6c-dirty Pierre2324#3
[   12.682377] Call trace:
[   12.682386] [<ffffffc000088ae8>] dump_backtrace+0x0/0x148
[   12.682393] [<ffffffc000088c40>] show_stack+0x10/0x20
[   12.682403] [<ffffffc000fbf398>] dump_stack+0x1c/0x28
[   12.682409] [<ffffffc0000a25ac>] warn_slowpath_fmt+0x8c/0x100
[   12.682416] [<ffffffc00010ca74>] pm_qos_update_request+0x1cc/0x2c8
[   12.682424] [<ffffffc0009335ac>] msm_pm_qos_update_request+0x3c/0x50
[   12.682429] [<ffffffc00093476c>] camera_v4l2_open+0x164/0x4f0
[   12.682437] [<ffffffc0008c70f4>] v4l2_open+0x9c/0x110
[   12.682444] [<ffffffc00020be04>] chrdev_open+0xa4/0x200
[   12.682452] [<ffffffc000201344>] finish_open+0x1fc/0x2b0
[   12.682459] [<ffffffc000218058>] do_last.isra.12+0x4a8/0xcd0
[   12.682465] [<ffffffc000219c10>] path_openat.isra.13+0x108/0x910
[   12.682471] [<ffffffc00021be64>] do_filp_open+0x2c/0x98
[   12.682476] [<ffffffc000202e68>] do_sys_open+0xf8/0x1e8
[   12.682482] [<ffffffc00026a760>] compat_SyS_openat+0x8/0x18
[   12.682486] ---[ end trace a76b7252eed261da ]---

msm_pm_qos_remove_request: remove request
        : pm_qos_remove_request() called for unknown object
        : ------------[ cut here ]------------
        : WARNING: CPU: 3 PID: 6528 at kernel/power/qos.c:744 pm_qos_remove_request+0x130/0x14c
        : Modules linked in: wlan(O) texfat(PO) machine_ext_dlkm(O) machine_dlkm(O) wcd9335_dlkm(O) cpe_lsm_dlkm(O) wcd_cpe_dlkm(O) analog_cdc_dlkm(O) digital_cdc_dlkm(O) stub_dlkm(O) mbhc_dlkm(O) wsa881x_analog_dlkm(O) wsa881x_dlkm(O) wcd9xxx_dlkm(O) wcd_core_dlkm(O) hdmi_dlkm(O) swr_ctrl_dlkm(O) swr_dlkm(O) pinctrl_wcd_dlkm(O) native_dlkm(O) platform_dlkm(O) usf_dlkm(O) q6_dlkm(O) adsp_loader_dlkm(O) apr_dlkm(O) q6_notifier_dlkm(O)
        : CPU: 3 PID: 6528 Comm: provider@2.4-se Tainted: P S         O    4.9.334+ Pierre2324#2
Hardware name: Qualcomm Technologies, Inc. SDM632 PMI632 MTP S3 (DT)
task    : 0000000067cf7cc5 task.stack: 00000000648a024e
        : PC is at pm_qos_remove_request+0x130/0x14c
        : LR is at pm_qos_remove_request+0x130/0x14c
pc      : [<ffffff9dee934148>] lr : [<ffffff9dee934148>] pstate: 60400145
sp      : ffffffe2b6d0b9f0
        : x29: ffffffe2b6d0b9f0 x28: ffffffe2213498a8
        : x27: 0000000000000009 x26: ffffffe27f70c400
        : x25: ffffff9df0745000 x24: ffffff9df10fd4e0
        : x23: ffffffe2e6d96030 x22: ffffff9defd6e210
        : x21: ffffff9defd6e227 x20: ffffff9df07450a0
        : x19: ffffff9df10fd3b0 x18: 0000000000000000
        : x17: 00000000000c5fc8 x16: 0000000000000000
        : x15: 0000004501639000 x14: ffffffe2b6d0b7e0
        : x13: 0000000000000004 x12: 000000006ff1b4c0
        : x11: 0000000000000015 x10: 000000000682aaab
        : x9 : c366d0a2f1cecf00 x8 : c366d0a2f1cecf00
        : x7 : 0000000000000000 x6 : ffffffe2f15a6079
        : x5 : 0000000000000000 x4 : 0000000000000004
        : x3 : ffffffe2b6d0b738 x2 : ffffff9dee892414
        : x1 : ffffff9dee93acb8 x0 : 0000000000000031
PC      : pm_qos_remove_request+0xf0/0x14c:

Signed-off-by: Ji Huang <cocafehj@gmail.com>

Change-Id: Icc745fa61565e6a3dfc39ffab8c51eada7d674aa
haikaru17 pushed a commit to haikaru17/NGK_android_kernel_xiaomi_sdm845 that referenced this issue Jul 10, 2024
… delayed items

commit e110f8911ddb93e6f55da14ccbbe705397b30d0b upstream.

When running delayed items we are holding a delayed node's mutex and then
we will attempt to modify a subvolume btree to insert/update/delete the
delayed items. However if have an error during the insertions for example,
btrfs_insert_delayed_items() may return with a path that has locked extent
buffers (a leaf at the very least), and then we attempt to release the
delayed node at __btrfs_run_delayed_items(), which requires taking the
delayed node's mutex, causing an ABBA type of deadlock. This was reported
by syzbot and the lockdep splat is the following:

  WARNING: possible circular locking dependency detected
  6.5.0-rc7-syzkaller-00024-g93f5de5f648d #0 Not tainted
  ------------------------------------------------------
  syz-executor.2/13257 is trying to acquire lock:
  ffff88801835c0c0 (&delayed_node->mutex){+.+.}-{3:3}, at: __btrfs_release_delayed_node+0x9a/0xaa0 fs/btrfs/delayed-inode.c:256

  but task is already holding lock:
  ffff88802a5ab8e8 (btrfs-tree-00){++++}-{3:3}, at: __btrfs_tree_lock+0x3c/0x2a0 fs/btrfs/locking.c:198

  which lock already depends on the new lock.

  the existing dependency chain (in reverse order) is:

  -> Pierre2324#1 (btrfs-tree-00){++++}-{3:3}:
         __lock_release kernel/locking/lockdep.c:5475 [inline]
         lock_release+0x36f/0x9d0 kernel/locking/lockdep.c:5781
         up_write+0x79/0x580 kernel/locking/rwsem.c:1625
         btrfs_tree_unlock_rw fs/btrfs/locking.h:189 [inline]
         btrfs_unlock_up_safe+0x179/0x3b0 fs/btrfs/locking.c:239
         search_leaf fs/btrfs/ctree.c:1986 [inline]
         btrfs_search_slot+0x2511/0x2f80 fs/btrfs/ctree.c:2230
         btrfs_insert_empty_items+0x9c/0x180 fs/btrfs/ctree.c:4376
         btrfs_insert_delayed_item fs/btrfs/delayed-inode.c:746 [inline]
         btrfs_insert_delayed_items fs/btrfs/delayed-inode.c:824 [inline]
         __btrfs_commit_inode_delayed_items+0xd24/0x2410 fs/btrfs/delayed-inode.c:1111
         __btrfs_run_delayed_items+0x1db/0x430 fs/btrfs/delayed-inode.c:1153
         flush_space+0x269/0xe70 fs/btrfs/space-info.c:723
         btrfs_async_reclaim_metadata_space+0x106/0x350 fs/btrfs/space-info.c:1078
         process_one_work+0x92c/0x12c0 kernel/workqueue.c:2600
         worker_thread+0xa63/0x1210 kernel/workqueue.c:2751
         kthread+0x2b8/0x350 kernel/kthread.c:389
         ret_from_fork+0x2e/0x60 arch/x86/kernel/process.c:145
         ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:304

  -> #0 (&delayed_node->mutex){+.+.}-{3:3}:
         check_prev_add kernel/locking/lockdep.c:3142 [inline]
         check_prevs_add kernel/locking/lockdep.c:3261 [inline]
         validate_chain kernel/locking/lockdep.c:3876 [inline]
         __lock_acquire+0x39ff/0x7f70 kernel/locking/lockdep.c:5144
         lock_acquire+0x1e3/0x520 kernel/locking/lockdep.c:5761
         __mutex_lock_common+0x1d8/0x2530 kernel/locking/mutex.c:603
         __mutex_lock kernel/locking/mutex.c:747 [inline]
         mutex_lock_nested+0x1b/0x20 kernel/locking/mutex.c:799
         __btrfs_release_delayed_node+0x9a/0xaa0 fs/btrfs/delayed-inode.c:256
         btrfs_release_delayed_node fs/btrfs/delayed-inode.c:281 [inline]
         __btrfs_run_delayed_items+0x2b5/0x430 fs/btrfs/delayed-inode.c:1156
         btrfs_commit_transaction+0x859/0x2ff0 fs/btrfs/transaction.c:2276
         btrfs_sync_file+0xf56/0x1330 fs/btrfs/file.c:1988
         vfs_fsync_range fs/sync.c:188 [inline]
         vfs_fsync fs/sync.c:202 [inline]
         do_fsync fs/sync.c:212 [inline]
         __do_sys_fsync fs/sync.c:220 [inline]
         __se_sys_fsync fs/sync.c:218 [inline]
         __x64_sys_fsync+0x196/0x1e0 fs/sync.c:218
         do_syscall_x64 arch/x86/entry/common.c:50 [inline]
         do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
         entry_SYSCALL_64_after_hwframe+0x63/0xcd

  other info that might help us debug this:

   Possible unsafe locking scenario:

         CPU0                    CPU1
         ----                    ----
    lock(btrfs-tree-00);
                                 lock(&delayed_node->mutex);
                                 lock(btrfs-tree-00);
    lock(&delayed_node->mutex);

   *** DEADLOCK ***

  3 locks held by syz-executor.2/13257:
   #0: ffff88802c1ee370 (btrfs_trans_num_writers){++++}-{0:0}, at: spin_unlock include/linux/spinlock.h:391 [inline]
   #0: ffff88802c1ee370 (btrfs_trans_num_writers){++++}-{0:0}, at: join_transaction+0xb87/0xe00 fs/btrfs/transaction.c:287
   Pierre2324#1: ffff88802c1ee398 (btrfs_trans_num_extwriters){++++}-{0:0}, at: join_transaction+0xbb2/0xe00 fs/btrfs/transaction.c:288
   Pierre2324#2: ffff88802a5ab8e8 (btrfs-tree-00){++++}-{3:3}, at: __btrfs_tree_lock+0x3c/0x2a0 fs/btrfs/locking.c:198

  stack backtrace:
  CPU: 0 PID: 13257 Comm: syz-executor.2 Not tainted 6.5.0-rc7-syzkaller-00024-g93f5de5f648d #0
  Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/26/2023
  Call Trace:
   <TASK>
   __dump_stack lib/dump_stack.c:88 [inline]
   dump_stack_lvl+0x1e7/0x2d0 lib/dump_stack.c:106
   check_noncircular+0x375/0x4a0 kernel/locking/lockdep.c:2195
   check_prev_add kernel/locking/lockdep.c:3142 [inline]
   check_prevs_add kernel/locking/lockdep.c:3261 [inline]
   validate_chain kernel/locking/lockdep.c:3876 [inline]
   __lock_acquire+0x39ff/0x7f70 kernel/locking/lockdep.c:5144
   lock_acquire+0x1e3/0x520 kernel/locking/lockdep.c:5761
   __mutex_lock_common+0x1d8/0x2530 kernel/locking/mutex.c:603
   __mutex_lock kernel/locking/mutex.c:747 [inline]
   mutex_lock_nested+0x1b/0x20 kernel/locking/mutex.c:799
   __btrfs_release_delayed_node+0x9a/0xaa0 fs/btrfs/delayed-inode.c:256
   btrfs_release_delayed_node fs/btrfs/delayed-inode.c:281 [inline]
   __btrfs_run_delayed_items+0x2b5/0x430 fs/btrfs/delayed-inode.c:1156
   btrfs_commit_transaction+0x859/0x2ff0 fs/btrfs/transaction.c:2276
   btrfs_sync_file+0xf56/0x1330 fs/btrfs/file.c:1988
   vfs_fsync_range fs/sync.c:188 [inline]
   vfs_fsync fs/sync.c:202 [inline]
   do_fsync fs/sync.c:212 [inline]
   __do_sys_fsync fs/sync.c:220 [inline]
   __se_sys_fsync fs/sync.c:218 [inline]
   __x64_sys_fsync+0x196/0x1e0 fs/sync.c:218
   do_syscall_x64 arch/x86/entry/common.c:50 [inline]
   do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
   entry_SYSCALL_64_after_hwframe+0x63/0xcd
  RIP: 0033:0x7f3ad047cae9
  Code: 28 00 00 00 75 (...)
  RSP: 002b:00007f3ad12510c8 EFLAGS: 00000246 ORIG_RAX: 000000000000004a
  RAX: ffffffffffffffda RBX: 00007f3ad059bf80 RCX: 00007f3ad047cae9
  RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000005
  RBP: 00007f3ad04c847a R08: 0000000000000000 R09: 0000000000000000
  R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
  R13: 000000000000000b R14: 00007f3ad059bf80 R15: 00007ffe56af92f8
   </TASK>
  ------------[ cut here ]------------

Fix this by releasing the path before releasing the delayed node in the
error path at __btrfs_run_delayed_items().

Reported-by: syzbot+a379155f07c134ea9879@syzkaller.appspotmail.com
Link: https://lore.kernel.org/linux-btrfs/000000000000abba27060403b5bd@google.com/
CC: stable@vger.kernel.org # 4.14+
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Change-Id: I4995c41f897c5362f80cc9f4d2c636740dbaa83f
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
(cherry picked from commit 5a2bec32ebceb94bdcba2a513884739bee6d8d6b)
Signed-off-by: TogoFire <togofire@mailfence.com>
haikaru17 pushed a commit to haikaru17/NGK_android_kernel_xiaomi_sdm845 that referenced this issue Jul 10, 2024
commit cf129830ee820f7fc90b98df193cd49d49344d09 upstream.

When a match has been made to the nth duplicate symbol, return
success not error.

Example:

  Before:

    $ cat file.c
    cat: file.c: No such file or directory
    $ cat file1.c
    #include <stdio.h>

    static void func(void)
    {
            printf("First func\n");
    }

    void other(void);

    int main()
    {
            func();
            other();
            return 0;
    }
    $ cat file2.c
    #include <stdio.h>

    static void func(void)
    {
            printf("Second func\n");
    }

    void other(void)
    {
            func();
    }

    $ gcc -Wall -Wextra -o test file1.c file2.c
    $ perf record -e intel_pt//u --filter 'filter func @ ./test' -- ./test
    Multiple symbols with name 'func'
    Pierre2324#1      0x1149  l       func
                    which is near           main
    Pierre2324#2      0x1179  l       func
                    which is near           other
    Disambiguate symbol name by inserting #n after the name e.g. func Pierre2324#2
    Or select a global symbol by inserting #0 or #g or #G
    Failed to parse address filter: 'filter func @ ./test'
    Filter format is: filter|start|stop|tracestop <start symbol or address> [/ <end symbol or size>] [@<file name>]
    Where multiple filters are separated by space or comma.
    $ perf record -e intel_pt//u --filter 'filter func Pierre2324#2 @ ./test' -- ./test
    Failed to parse address filter: 'filter func Pierre2324#2 @ ./test'
    Filter format is: filter|start|stop|tracestop <start symbol or address> [/ <end symbol or size>] [@<file name>]
    Where multiple filters are separated by space or comma.

  After:

    $ perf record -e intel_pt//u --filter 'filter func Pierre2324#2 @ ./test' -- ./test
    First func
    Second func
    [ perf record: Woken up 1 times to write data ]
    [ perf record: Captured and wrote 0.016 MB perf.data ]
    $ perf script --itrace=b -Ftime,flags,ip,sym,addr --ns
    1231062.526977619:   tr strt                               0 [unknown] =>     558495708179 func
    1231062.526977619:   tr end  call               558495708188 func =>     558495708050 _init
    1231062.526979286:   tr strt                               0 [unknown] =>     55849570818d func
    1231062.526979286:   tr end  return             55849570818f func =>     55849570819d other

Fixes: 1b36c03 ("perf record: Add support for using symbols in address filters")
Reported-by: Dmitrii Dolgov <9erthalion6@gmail.com>
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Tested-by: Dmitry Dolgov <9erthalion6@gmail.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20230110185659.15979-1-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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