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Integrate kernel specific checkers - check-uapi-headers, sparse-check, checkpatch, dt-binding-check and dtb-check https://github.com/qualcomm-linux/kernel-checkers

Integrate kernel specific checkers - check-uapi-headers, sparse-check, checkpatch, dt-binding-check and dtb-check https://github.com/qualcomm-linux/kernel-checkers

Signed-off-by: VISHAL KUMAR <viskuma@qti.qualcomm.com>
@quic-viskuma quic-viskuma merged commit 8d8cacc into qcom-next May 19, 2025
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quic-viskuma pushed a commit that referenced this pull request May 22, 2025
Currently iwdev->rf is allocated in irdma_probe(), but free in
irdma_ib_dealloc_device(). It can be misleading. Move the free to
irdma_remove() to be more obvious.

Freeing in irdma_ib_dealloc_device() leads to KASAN use-after-free
issue. Which can also lead to NULL pointer dereference. Fix this.

irdma_deinit_interrupts() can't be moved before freeing iwdef->rf,
because in this case deinit interrupts will be done before freeing irqs.
The simplest solution is to move kfree(iwdev->rf) to irdma_remove().

Reproducer:
  sudo rmmod irdma

Minified splat(s):
  BUG: KASAN: use-after-free in irdma_remove+0x257/0x2d0 [irdma]
  Call Trace:
   <TASK>
   ? __pfx__raw_spin_lock_irqsave+0x10/0x10
   ? kfree+0x253/0x450
   ? irdma_remove+0x257/0x2d0 [irdma]
   kasan_report+0xed/0x120
   ? irdma_remove+0x257/0x2d0 [irdma]
   irdma_remove+0x257/0x2d0 [irdma]
   auxiliary_bus_remove+0x56/0x80
   device_release_driver_internal+0x371/0x530
   ? kernfs_put.part.0+0x147/0x310
   driver_detach+0xbf/0x180
   bus_remove_driver+0x11b/0x2a0
   auxiliary_driver_unregister+0x1a/0x50
   irdma_exit_module+0x40/0x4c [irdma]

  Oops: general protection fault, probably for non-canonical address 0xdffffc0000000000: 0000 [#1] PREEMPT SMP KASAN NOPTI
  KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007]
  RIP: 0010:ice_free_rdma_qvector+0x2a/0xa0 [ice]
  Call Trace:
   ? ice_free_rdma_qvector+0x2a/0xa0 [ice]
   irdma_remove+0x179/0x2d0 [irdma]
   auxiliary_bus_remove+0x56/0x80
   device_release_driver_internal+0x371/0x530
   ? kobject_put+0x61/0x4b0
   driver_detach+0xbf/0x180
   bus_remove_driver+0x11b/0x2a0
   auxiliary_driver_unregister+0x1a/0x50
   irdma_exit_module+0x40/0x4c [irdma]

Reported-by: Marcin Szycik <marcin.szycik@linux.intel.com>
Closes: https://lore.kernel.org/netdev/8e533834-4564-472f-b29b-4f1cb7730053@linux.intel.com/
Fixes: 3e0d3cb ("ice, irdma: move interrupts code to irdma")
Reviewed-by: Marcin Szycik <marcin.szycik@linux.intel.com>
Signed-off-by: Michal Swiatkowski <michal.swiatkowski@linux.intel.com>
Signed-off-by: Tatyana Nikolova <tatyana.e.nikolova@intel.com>
Link: https://patch.msgid.link/20250414234231.523-1-tatyana.e.nikolova@intel.com
Signed-off-by: Leon Romanovsky <leon@kernel.org>
quic-viskuma pushed a commit that referenced this pull request May 22, 2025
When memory is insufficient, the allocation of nfs_lock_context in
nfs_get_lock_context() fails and returns -ENOMEM. If we mistakenly treat
an nfs4_unlockdata structure (whose l_ctx member has been set to -ENOMEM)
as valid and proceed to execute rpc_run_task(), this will trigger a NULL
pointer dereference in nfs4_locku_prepare. For example:

BUG: kernel NULL pointer dereference, address: 000000000000000c
PGD 0 P4D 0
Oops: Oops: 0000 [#1] SMP PTI
CPU: 15 UID: 0 PID: 12 Comm: kworker/u64:0 Not tainted 6.15.0-rc2-dirty qualcomm-linux#60
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.3-2.fc40
Workqueue: rpciod rpc_async_schedule
RIP: 0010:nfs4_locku_prepare+0x35/0xc2
Code: 89 f2 48 89 fd 48 c7 c7 68 69 ef b5 53 48 8b 8e 90 00 00 00 48 89 f3
RSP: 0018:ffffbbafc006bdb8 EFLAGS: 00010246
RAX: 000000000000004b RBX: ffff9b964fc1fa00 RCX: 0000000000000000
RDX: 0000000000000000 RSI: fffffffffffffff4 RDI: ffff9ba53fddbf40
RBP: ffff9ba539934000 R08: 0000000000000000 R09: ffffbbafc006bc38
R10: ffffffffb6b689c8 R11: 0000000000000003 R12: ffff9ba539934030
R13: 0000000000000001 R14: 0000000004248060 R15: ffffffffb56d1c30
FS: 0000000000000000(0000) GS:ffff9ba5881f0000(0000) knlGS:00000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000000000000c CR3: 000000093f244000 CR4: 00000000000006f0
Call Trace:
 <TASK>
 __rpc_execute+0xbc/0x480
 rpc_async_schedule+0x2f/0x40
 process_one_work+0x232/0x5d0
 worker_thread+0x1da/0x3d0
 ? __pfx_worker_thread+0x10/0x10
 kthread+0x10d/0x240
 ? __pfx_kthread+0x10/0x10
 ret_from_fork+0x34/0x50
 ? __pfx_kthread+0x10/0x10
 ret_from_fork_asm+0x1a/0x30
 </TASK>
Modules linked in:
CR2: 000000000000000c
---[ end trace 0000000000000000 ]---

Free the allocated nfs4_unlockdata when nfs_get_lock_context() fails and
return NULL to terminate subsequent rpc_run_task, preventing NULL pointer
dereference.

Fixes: f30cb75 ("NFS: Always wait for I/O completion before unlock")
Signed-off-by: Li Lingfeng <lilingfeng3@huawei.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Link: https://lore.kernel.org/r/20250417072508.3850532-1-lilingfeng3@huawei.com
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
quic-viskuma pushed a commit that referenced this pull request May 22, 2025
When CONFIG_PROVE_RCU_LIST is enabled, fprobe triggers the following
warning:

    WARNING: suspicious RCU usage
    kernel/trace/fprobe.c:457 RCU-list traversed in non-reader section!!

    other info that might help us debug this:
	#1: ffffffff863c4e08 (fprobe_mutex){+.+.}-{4:4}, at: fprobe_module_callback+0x7b/0x8c0

    Call Trace:
	fprobe_module_callback
	notifier_call_chain
	blocking_notifier_call_chain

This warning occurs because fprobe_remove_node_in_module() traverses an
RCU list using RCU primitives without holding an RCU read lock. However,
the function is only called from fprobe_module_callback(), which holds
the fprobe_mutex lock that provides sufficient protection for safely
traversing the list.

Fix the warning by specifying the locking design to the
CONFIG_PROVE_RCU_LIST mechanism. Add the lockdep_is_held() argument to
hlist_for_each_entry_rcu() to inform the RCU checker that fprobe_mutex
provides the required protection.

Link: https://lore.kernel.org/all/20250410-fprobe-v1-1-068ef5f41436@debian.org/

Fixes: a3dc298 ("tracing: fprobe: Cleanup fprobe hash when module unloading")
Signed-off-by: Breno Leitao <leitao@debian.org>
Tested-by: Antonio Quartulli <antonio@mandelbit.com>
Tested-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
quic-viskuma pushed a commit that referenced this pull request May 22, 2025
If the discard worker is running and there's currently only one block
group, that block group is a data block group, it's in the unused block
groups discard list and is being used (it got an extent allocated from it
after becoming unused), the worker can end up in an infinite loop if a
transaction abort happens or the async discard is disabled (during remount
or unmount for example).

This happens like this:

1) Task A, the discard worker, is at peek_discard_list() and
   find_next_block_group() returns block group X;

2) Block group X is in the unused block groups discard list (its discard
   index is BTRFS_DISCARD_INDEX_UNUSED) since at some point in the past
   it become an unused block group and was added to that list, but then
   later it got an extent allocated from it, so its ->used counter is not
   zero anymore;

3) The current transaction is aborted by task B and we end up at
   __btrfs_handle_fs_error() in the transaction abort path, where we call
   btrfs_discard_stop(), which clears BTRFS_FS_DISCARD_RUNNING from
   fs_info, and then at __btrfs_handle_fs_error() we set the fs to RO mode
   (setting SB_RDONLY in the super block's s_flags field);

4) Task A calls __add_to_discard_list() with the goal of moving the block
   group from the unused block groups discard list into another discard
   list, but at __add_to_discard_list() we end up doing nothing because
   btrfs_run_discard_work() returns false, since the super block has
   SB_RDONLY set in its flags and BTRFS_FS_DISCARD_RUNNING is not set
   anymore in fs_info->flags. So block group X remains in the unused block
   groups discard list;

5) Task A then does a goto into the 'again' label, calls
   find_next_block_group() again we gets block group X again. Then it
   repeats the previous steps over and over since there are not other
   block groups in the discard lists and block group X is never moved
   out of the unused block groups discard list since
   btrfs_run_discard_work() keeps returning false and therefore
   __add_to_discard_list() doesn't move block group X out of that discard
   list.

When this happens we can get a soft lockup report like this:

  [71.957] watchdog: BUG: soft lockup - CPU#0 stuck for 27s! [kworker/u4:3:97]
  [71.957] Modules linked in: xfs af_packet rfkill (...)
  [71.957] CPU: 0 UID: 0 PID: 97 Comm: kworker/u4:3 Tainted: G        W          6.14.2-1-default #1 openSUSE Tumbleweed 968795ef2b1407352128b466fe887416c33af6fa
  [71.957] Tainted: [W]=WARN
  [71.957] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.2-3-gd478f380-rebuilt.opensuse.org 04/01/2014
  [71.957] Workqueue: btrfs_discard btrfs_discard_workfn [btrfs]
  [71.957] RIP: 0010:btrfs_discard_workfn+0xc4/0x400 [btrfs]
  [71.957] Code: c1 01 48 83 (...)
  [71.957] RSP: 0018:ffffafaec03efe08 EFLAGS: 00000246
  [71.957] RAX: ffff897045500000 RBX: ffff8970413ed8d0 RCX: 0000000000000000
  [71.957] RDX: 0000000000000001 RSI: ffff8970413ed8d0 RDI: 0000000a8f1272ad
  [71.957] RBP: 0000000a9d61c60e R08: ffff897045500140 R09: 8080808080808080
  [71.957] R10: ffff897040276800 R11: fefefefefefefeff R12: ffff8970413ed860
  [71.957] R13: ffff897045500000 R14: ffff8970413ed868 R15: 0000000000000000
  [71.957] FS:  0000000000000000(0000) GS:ffff89707bc00000(0000) knlGS:0000000000000000
  [71.957] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  [71.957] CR2: 00005605bcc8d2f0 CR3: 000000010376a001 CR4: 0000000000770ef0
  [71.957] PKRU: 55555554
  [71.957] Call Trace:
  [71.957]  <TASK>
  [71.957]  process_one_work+0x17e/0x330
  [71.957]  worker_thread+0x2ce/0x3f0
  [71.957]  ? __pfx_worker_thread+0x10/0x10
  [71.957]  kthread+0xef/0x220
  [71.957]  ? __pfx_kthread+0x10/0x10
  [71.957]  ret_from_fork+0x34/0x50
  [71.957]  ? __pfx_kthread+0x10/0x10
  [71.957]  ret_from_fork_asm+0x1a/0x30
  [71.957]  </TASK>
  [71.957] Kernel panic - not syncing: softlockup: hung tasks
  [71.987] CPU: 0 UID: 0 PID: 97 Comm: kworker/u4:3 Tainted: G        W    L     6.14.2-1-default #1 openSUSE Tumbleweed 968795ef2b1407352128b466fe887416c33af6fa
  [71.989] Tainted: [W]=WARN, [L]=SOFTLOCKUP
  [71.989] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.2-3-gd478f380-rebuilt.opensuse.org 04/01/2014
  [71.991] Workqueue: btrfs_discard btrfs_discard_workfn [btrfs]
  [71.992] Call Trace:
  [71.993]  <IRQ>
  [71.994]  dump_stack_lvl+0x5a/0x80
  [71.994]  panic+0x10b/0x2da
  [71.995]  watchdog_timer_fn.cold+0x9a/0xa1
  [71.996]  ? __pfx_watchdog_timer_fn+0x10/0x10
  [71.997]  __hrtimer_run_queues+0x132/0x2a0
  [71.997]  hrtimer_interrupt+0xff/0x230
  [71.998]  __sysvec_apic_timer_interrupt+0x55/0x100
  [71.999]  sysvec_apic_timer_interrupt+0x6c/0x90
  [72.000]  </IRQ>
  [72.000]  <TASK>
  [72.001]  asm_sysvec_apic_timer_interrupt+0x1a/0x20
  [72.002] RIP: 0010:btrfs_discard_workfn+0xc4/0x400 [btrfs]
  [72.002] Code: c1 01 48 83 (...)
  [72.005] RSP: 0018:ffffafaec03efe08 EFLAGS: 00000246
  [72.006] RAX: ffff897045500000 RBX: ffff8970413ed8d0 RCX: 0000000000000000
  [72.006] RDX: 0000000000000001 RSI: ffff8970413ed8d0 RDI: 0000000a8f1272ad
  [72.007] RBP: 0000000a9d61c60e R08: ffff897045500140 R09: 8080808080808080
  [72.008] R10: ffff897040276800 R11: fefefefefefefeff R12: ffff8970413ed860
  [72.009] R13: ffff897045500000 R14: ffff8970413ed868 R15: 0000000000000000
  [72.010]  ? btrfs_discard_workfn+0x51/0x400 [btrfs 23b01089228eb964071fb7ca156eee8cd3bf996f]
  [72.011]  process_one_work+0x17e/0x330
  [72.012]  worker_thread+0x2ce/0x3f0
  [72.013]  ? __pfx_worker_thread+0x10/0x10
  [72.014]  kthread+0xef/0x220
  [72.014]  ? __pfx_kthread+0x10/0x10
  [72.015]  ret_from_fork+0x34/0x50
  [72.015]  ? __pfx_kthread+0x10/0x10
  [72.016]  ret_from_fork_asm+0x1a/0x30
  [72.017]  </TASK>
  [72.017] Kernel Offset: 0x15000000 from 0xffffffff81000000 (relocation range: 0xffffffff80000000-0xffffffffbfffffff)
  [72.019] Rebooting in 90 seconds..

So fix this by making sure we move a block group out of the unused block
groups discard list when calling __add_to_discard_list().

Fixes: 2bee7eb ("btrfs: discard one region at a time in async discard")
Link: https://bugzilla.suse.com/show_bug.cgi?id=1242012
CC: stable@vger.kernel.org # 5.10+
Reviewed-by: Boris Burkov <boris@bur.io>
Reviewed-by: Daniel Vacek <neelx@suse.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
quic-viskuma pushed a commit that referenced this pull request May 22, 2025
MACsec offload is not supported in switchdev mode for uplink
representors. When switching to the uplink representor profile, the
MACsec offload feature must be cleared from the netdevice's features.

If left enabled, attempts to add offloads result in a null pointer
dereference, as the uplink representor does not support MACsec offload
even though the feature bit remains set.

Clear NETIF_F_HW_MACSEC in mlx5e_fix_uplink_rep_features().

Kernel log:

Oops: general protection fault, probably for non-canonical address 0xdffffc000000000f: 0000 [#1] SMP KASAN
KASAN: null-ptr-deref in range [0x0000000000000078-0x000000000000007f]
CPU: 29 UID: 0 PID: 4714 Comm: ip Not tainted 6.14.0-rc4_for_upstream_debug_2025_03_02_17_35 #1
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.16.0-0-gd239552ce722-prebuilt.qemu.org 04/01/2014
RIP: 0010:__mutex_lock+0x128/0x1dd0
Code: d0 7c 08 84 d2 0f 85 ad 15 00 00 8b 35 91 5c fe 03 85 f6 75 29 49 8d 7e 60 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 a6 15 00 00 4d 3b 76 60 0f 85 fd 0b 00 00 65 ff
RSP: 0018:ffff888147a4f160 EFLAGS: 00010206
RAX: dffffc0000000000 RBX: 0000000000000000 RCX: 0000000000000001
RDX: 000000000000000f RSI: 0000000000000000 RDI: 0000000000000078
RBP: ffff888147a4f2e0 R08: ffffffffa05d2c19 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: 0000000000000000
R13: dffffc0000000000 R14: 0000000000000018 R15: ffff888152de0000
FS:  00007f855e27d800(0000) GS:ffff88881ee80000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000004e5768 CR3: 000000013ae7c005 CR4: 0000000000372eb0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe07f0 DR7: 0000000000000400
Call Trace:
 <TASK>
 ? die_addr+0x3d/0xa0
 ? exc_general_protection+0x144/0x220
 ? asm_exc_general_protection+0x22/0x30
 ? mlx5e_macsec_add_secy+0xf9/0x700 [mlx5_core]
 ? __mutex_lock+0x128/0x1dd0
 ? lockdep_set_lock_cmp_fn+0x190/0x190
 ? mlx5e_macsec_add_secy+0xf9/0x700 [mlx5_core]
 ? mutex_lock_io_nested+0x1ae0/0x1ae0
 ? lock_acquire+0x1c2/0x530
 ? macsec_upd_offload+0x145/0x380
 ? lockdep_hardirqs_on_prepare+0x400/0x400
 ? kasan_save_stack+0x30/0x40
 ? kasan_save_stack+0x20/0x40
 ? kasan_save_track+0x10/0x30
 ? __kasan_kmalloc+0x77/0x90
 ? __kmalloc_noprof+0x249/0x6b0
 ? genl_family_rcv_msg_attrs_parse.constprop.0+0xb5/0x240
 ? mlx5e_macsec_add_secy+0xf9/0x700 [mlx5_core]
 mlx5e_macsec_add_secy+0xf9/0x700 [mlx5_core]
 ? mlx5e_macsec_add_rxsa+0x11a0/0x11a0 [mlx5_core]
 macsec_update_offload+0x26c/0x820
 ? macsec_set_mac_address+0x4b0/0x4b0
 ? lockdep_hardirqs_on_prepare+0x284/0x400
 ? _raw_spin_unlock_irqrestore+0x47/0x50
 macsec_upd_offload+0x2c8/0x380
 ? macsec_update_offload+0x820/0x820
 ? __nla_parse+0x22/0x30
 ? genl_family_rcv_msg_attrs_parse.constprop.0+0x15e/0x240
 genl_family_rcv_msg_doit+0x1cc/0x2a0
 ? genl_family_rcv_msg_attrs_parse.constprop.0+0x240/0x240
 ? cap_capable+0xd4/0x330
 genl_rcv_msg+0x3ea/0x670
 ? genl_family_rcv_msg_dumpit+0x2a0/0x2a0
 ? lockdep_set_lock_cmp_fn+0x190/0x190
 ? macsec_update_offload+0x820/0x820
 netlink_rcv_skb+0x12b/0x390
 ? genl_family_rcv_msg_dumpit+0x2a0/0x2a0
 ? netlink_ack+0xd80/0xd80
 ? rwsem_down_read_slowpath+0xf90/0xf90
 ? netlink_deliver_tap+0xcd/0xac0
 ? netlink_deliver_tap+0x155/0xac0
 ? _copy_from_iter+0x1bb/0x12c0
 genl_rcv+0x24/0x40
 netlink_unicast+0x440/0x700
 ? netlink_attachskb+0x760/0x760
 ? lock_acquire+0x1c2/0x530
 ? __might_fault+0xbb/0x170
 netlink_sendmsg+0x749/0xc10
 ? netlink_unicast+0x700/0x700
 ? __might_fault+0xbb/0x170
 ? netlink_unicast+0x700/0x700
 __sock_sendmsg+0xc5/0x190
 ____sys_sendmsg+0x53f/0x760
 ? import_iovec+0x7/0x10
 ? kernel_sendmsg+0x30/0x30
 ? __copy_msghdr+0x3c0/0x3c0
 ? filter_irq_stacks+0x90/0x90
 ? stack_depot_save_flags+0x28/0xa30
 ___sys_sendmsg+0xeb/0x170
 ? kasan_save_stack+0x30/0x40
 ? copy_msghdr_from_user+0x110/0x110
 ? do_syscall_64+0x6d/0x140
 ? lock_acquire+0x1c2/0x530
 ? __virt_addr_valid+0x116/0x3b0
 ? __virt_addr_valid+0x1da/0x3b0
 ? lock_downgrade+0x680/0x680
 ? __delete_object+0x21/0x50
 __sys_sendmsg+0xf7/0x180
 ? __sys_sendmsg_sock+0x20/0x20
 ? kmem_cache_free+0x14c/0x4e0
 ? __x64_sys_close+0x78/0xd0
 do_syscall_64+0x6d/0x140
 entry_SYSCALL_64_after_hwframe+0x4b/0x53
RIP: 0033:0x7f855e113367
Code: 0e 00 f7 d8 64 89 02 48 c7 c0 ff ff ff ff eb b9 0f 1f 00 f3 0f 1e fa 64 8b 04 25 18 00 00 00 85 c0 75 10 b8 2e 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 51 c3 48 83 ec 28 89 54 24 1c 48 89 74 24 10
RSP: 002b:00007ffd15e90c88 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 0000000000000002 RCX: 00007f855e113367
RDX: 0000000000000000 RSI: 00007ffd15e90cf0 RDI: 0000000000000004
RBP: 00007ffd15e90dbc R08: 0000000000000028 R09: 000000000045d100
R10: 00007f855e011dd8 R11: 0000000000000246 R12: 0000000000000019
R13: 0000000067c6b785 R14: 00000000004a1e80 R15: 0000000000000000
 </TASK>
Modules linked in: 8021q garp mrp sch_ingress openvswitch nsh mlx5_ib mlx5_fwctl mlx5_dpll mlx5_core rpcrdma rdma_ucm ib_iser libiscsi scsi_transport_iscsi ib_umad rdma_cm ib_ipoib iw_cm ib_cm ib_uverbs ib_core xt_conntrack xt_MASQUERADE nf_conntrack_netlink nfnetlink xt_addrtype iptable_nat nf_nat br_netfilter rpcsec_gss_krb5 auth_rpcgss oid_registry overlay zram zsmalloc fuse [last unloaded: mlx5_core]
---[ end trace 0000000000000000 ]---

Fixes: 8ff0ac5 ("net/mlx5: Add MACsec offload Tx command support")
Signed-off-by: Carolina Jubran <cjubran@nvidia.com>
Reviewed-by: Shahar Shitrit <shshitrit@nvidia.com>
Reviewed-by: Dragos Tatulea <dtatulea@nvidia.com>
Signed-off-by: Tariq Toukan <tariqt@nvidia.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/1746958552-561295-1-git-send-email-tariqt@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
quic-viskuma pushed a commit that referenced this pull request May 22, 2025
…unload

Kernel panic occurs when a devmem TCP socket is closed after NIC module
is unloaded.

This is Devmem TCP unregistration scenarios. number is an order.
(a)netlink socket close    (b)pp destroy    (c)uninstall    result
1                          2                3               OK
1                          3                2               (d)Impossible
2                          1                3               OK
3                          1                2               (e)Kernel panic
2                          3                1               (d)Impossible
3                          2                1               (d)Impossible

(a) netdev_nl_sock_priv_destroy() is called when devmem TCP socket is
    closed.
(b) page_pool_destroy() is called when the interface is down.
(c) mp_ops->uninstall() is called when an interface is unregistered.
(d) There is no scenario in mp_ops->uninstall() is called before
    page_pool_destroy().
    Because unregister_netdevice_many_notify() closes interfaces first
    and then calls mp_ops->uninstall().
(e) netdev_nl_sock_priv_destroy() accesses struct net_device to acquire
    netdev_lock().
    But if the interface module has already been removed, net_device
    pointer is invalid, so it causes kernel panic.

In summary, there are only 3 possible scenarios.
 A. sk close -> pp destroy -> uninstall.
 B. pp destroy -> sk close -> uninstall.
 C. pp destroy -> uninstall -> sk close.

Case C is a kernel panic scenario.

In order to fix this problem, It makes mp_dmabuf_devmem_uninstall() set
binding->dev to NULL.
It indicates an bound net_device was unregistered.

It makes netdev_nl_sock_priv_destroy() do not acquire netdev_lock()
if binding->dev is NULL.

A new binding->lock is added to protect a dev of a binding.
So, lock ordering is like below.
 priv->lock
 netdev_lock(dev)
 binding->lock

Tests:
Scenario A:
    ./ncdevmem -s 192.168.1.4 -c 192.168.1.2 -f $interface -l -p 8000 \
        -v 7 -t 1 -q 1 &
    pid=$!
    sleep 10
    kill $pid
    ip link set $interface down
    modprobe -rv $module

Scenario B:
    ./ncdevmem -s 192.168.1.4 -c 192.168.1.2 -f $interface -l -p 8000 \
        -v 7 -t 1 -q 1 &
    pid=$!
    sleep 10
    ip link set $interface down
    kill $pid
    modprobe -rv $module

Scenario C:
    ./ncdevmem -s 192.168.1.4 -c 192.168.1.2 -f $interface -l -p 8000 \
        -v 7 -t 1 -q 1 &
    pid=$!
    sleep 10
    modprobe -rv $module
    sleep 5
    kill $pid

Splat looks like:
Oops: general protection fault, probably for non-canonical address 0xdffffc001fffa9f7: 0000 [#1] SMP DEBUG_PAGEALLOC KASAN NOPTI
KASAN: probably user-memory-access in range [0x00000000fffd4fb8-0x00000000fffd4fbf]
CPU: 0 UID: 0 PID: 2041 Comm: ncdevmem Tainted: G    B   W           6.15.0-rc1+ qualcomm-linux#2 PREEMPT(undef)  0947ec89efa0fd68838b78e36aa1617e97ff5d7f
Tainted: [B]=BAD_PAGE, [W]=WARN
RIP: 0010:__mutex_lock (./include/linux/sched.h:2244 kernel/locking/mutex.c:400 kernel/locking/mutex.c:443 kernel/locking/mutex.c:605 kernel/locking/mutex.c:746)
Code: ea 03 80 3c 02 00 0f 85 4f 13 00 00 49 8b 1e 48 83 e3 f8 74 6a 48 b8 00 00 00 00 00 fc ff df 48 8d 7b 34 48 89 fa 48 c1 ea 03 <0f> b6 f
RSP: 0018:ffff88826f7ef730 EFLAGS: 00010203
RAX: dffffc0000000000 RBX: 00000000fffd4f88 RCX: ffffffffaa9bc811
RDX: 000000001fffa9f7 RSI: 0000000000000008 RDI: 00000000fffd4fbc
RBP: ffff88826f7ef8b0 R08: 0000000000000000 R09: ffffed103e6aa1a4
R10: 0000000000000007 R11: ffff88826f7ef442 R12: fffffbfff669f65e
R13: ffff88812a830040 R14: ffff8881f3550d20 R15: 00000000fffd4f88
FS:  0000000000000000(0000) GS:ffff888866c05000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000563bed0cb288 CR3: 00000001a7c98000 CR4: 00000000007506f0
PKRU: 55555554
Call Trace:
<TASK>
 ...
 netdev_nl_sock_priv_destroy (net/core/netdev-genl.c:953 (discriminator 3))
 genl_release (net/netlink/genetlink.c:653 net/netlink/genetlink.c:694 net/netlink/genetlink.c:705)
 ...
 netlink_release (net/netlink/af_netlink.c:737)
 ...
 __sock_release (net/socket.c:647)
 sock_close (net/socket.c:1393)

Fixes: 1d22d30 ("net: drop rtnl_lock for queue_mgmt operations")
Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Acked-by: Stanislav Fomichev <sdf@fomichev.me>
Link: https://patch.msgid.link/20250514154028.1062909-1-ap420073@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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