Security Vulnerabilities
- CVEs Published In June 2025
In the Linux kernel, the following vulnerability has been resolved:
drm/amd/display: Check correct bounds for stream encoder instances for DCN303
[Why & How]
eng_id for DCN303 cannot be more than 1, since we have only two
instances of stream encoders.
Check the correct boundary condition for engine ID for DCN303 prevent
the potential out of bounds access.
In the Linux kernel, the following vulnerability has been resolved:
tee: add overflow check in register_shm_helper()
With special lengths supplied by user space, register_shm_helper() has
an integer overflow when calculating the number of pages covered by a
supplied user space memory region.
This causes internal_get_user_pages_fast() a helper function of
pin_user_pages_fast() to do a NULL pointer dereference:
Unable to handle kernel NULL pointer dereference at virtual address 0000000000000010
Modules linked in:
CPU: 1 PID: 173 Comm: optee_example_a Not tainted 5.19.0 #11
Hardware name: QEMU QEMU Virtual Machine, BIOS 0.0.0 02/06/2015
pc : internal_get_user_pages_fast+0x474/0xa80
Call trace:
internal_get_user_pages_fast+0x474/0xa80
pin_user_pages_fast+0x24/0x4c
register_shm_helper+0x194/0x330
tee_shm_register_user_buf+0x78/0x120
tee_ioctl+0xd0/0x11a0
__arm64_sys_ioctl+0xa8/0xec
invoke_syscall+0x48/0x114
Fix this by adding an an explicit call to access_ok() in
tee_shm_register_user_buf() to catch an invalid user space address
early.
In the Linux kernel, the following vulnerability has been resolved:
net: dsa: felix: suppress non-changes to the tagging protocol
The way in which dsa_tree_change_tag_proto() works is that when
dsa_tree_notify() fails, it doesn't know whether the operation failed
mid way in a multi-switch tree, or it failed for a single-switch tree.
So even though drivers need to fail cleanly in
ds->ops->change_tag_protocol(), DSA will still call dsa_tree_notify()
again, to restore the old tag protocol for potential switches in the
tree where the change did succeeed (before failing for others).
This means for the felix driver that if we report an error in
felix_change_tag_protocol(), we'll get another call where proto_ops ==
old_proto_ops. If we proceed to act upon that, we may do unexpected
things. For example, we will call dsa_tag_8021q_register() twice in a
row, without any dsa_tag_8021q_unregister() in between. Then we will
actually call dsa_tag_8021q_unregister() via old_proto_ops->teardown,
which (if it manages to run at all, after walking through corrupted data
structures) will leave the ports inoperational anyway.
The bug can be readily reproduced if we force an error while in
tag_8021q mode; this crashes the kernel.
echo ocelot-8021q > /sys/class/net/eno2/dsa/tagging
echo edsa > /sys/class/net/eno2/dsa/tagging # -EPROTONOSUPPORT
Unable to handle kernel NULL pointer dereference at virtual address 0000000000000014
Call trace:
vcap_entry_get+0x24/0x124
ocelot_vcap_filter_del+0x198/0x270
felix_tag_8021q_vlan_del+0xd4/0x21c
dsa_switch_tag_8021q_vlan_del+0x168/0x2cc
dsa_switch_event+0x68/0x1170
dsa_tree_notify+0x14/0x34
dsa_port_tag_8021q_vlan_del+0x84/0x110
dsa_tag_8021q_unregister+0x15c/0x1c0
felix_tag_8021q_teardown+0x16c/0x180
felix_change_tag_protocol+0x1bc/0x230
dsa_switch_event+0x14c/0x1170
dsa_tree_change_tag_proto+0x118/0x1c0
In the Linux kernel, the following vulnerability has been resolved:
virtio-blk: Avoid use-after-free on suspend/resume
hctx->user_data is set to vq in virtblk_init_hctx(). However, vq is
freed on suspend and reallocated on resume. So, hctx->user_data is
invalid after resume, and it will cause use-after-free accessing which
will result in the kernel crash something like below:
[ 22.428391] Call Trace:
[ 22.428899] <TASK>
[ 22.429339] virtqueue_add_split+0x3eb/0x620
[ 22.430035] ? __blk_mq_alloc_requests+0x17f/0x2d0
[ 22.430789] ? kvm_clock_get_cycles+0x14/0x30
[ 22.431496] virtqueue_add_sgs+0xad/0xd0
[ 22.432108] virtblk_add_req+0xe8/0x150
[ 22.432692] virtio_queue_rqs+0xeb/0x210
[ 22.433330] blk_mq_flush_plug_list+0x1b8/0x280
[ 22.434059] __blk_flush_plug+0xe1/0x140
[ 22.434853] blk_finish_plug+0x20/0x40
[ 22.435512] read_pages+0x20a/0x2e0
[ 22.436063] ? folio_add_lru+0x62/0xa0
[ 22.436652] page_cache_ra_unbounded+0x112/0x160
[ 22.437365] filemap_get_pages+0xe1/0x5b0
[ 22.437964] ? context_to_sid+0x70/0x100
[ 22.438580] ? sidtab_context_to_sid+0x32/0x400
[ 22.439979] filemap_read+0xcd/0x3d0
[ 22.440917] xfs_file_buffered_read+0x4a/0xc0
[ 22.441984] xfs_file_read_iter+0x65/0xd0
[ 22.442970] __kernel_read+0x160/0x2e0
[ 22.443921] bprm_execve+0x21b/0x640
[ 22.444809] do_execveat_common.isra.0+0x1a8/0x220
[ 22.446008] __x64_sys_execve+0x2d/0x40
[ 22.446920] do_syscall_64+0x37/0x90
[ 22.447773] entry_SYSCALL_64_after_hwframe+0x63/0xcd
This patch fixes this issue by getting vq from vblk, and removes
virtblk_init_hctx().
In the Linux kernel, the following vulnerability has been resolved:
virtio_net: fix memory leak inside XPD_TX with mergeable
When we call xdp_convert_buff_to_frame() to get xdpf, if it returns
NULL, we should check if xdp_page was allocated by xdp_linearize_page().
If it is newly allocated, it should be freed here alone. Just like any
other "goto err_xdp".
In the Linux kernel, the following vulnerability has been resolved:
net: atlantic: fix aq_vec index out of range error
The final update statement of the for loop exceeds the array range, the
dereference of self->aq_vec[i] is not checked and then leads to the
index out of range error.
Also fixed this kind of coding style in other for loop.
[ 97.937604] UBSAN: array-index-out-of-bounds in drivers/net/ethernet/aquantia/atlantic/aq_nic.c:1404:48
[ 97.937607] index 8 is out of range for type 'aq_vec_s *[8]'
[ 97.937608] CPU: 38 PID: 3767 Comm: kworker/u256:18 Not tainted 5.19.0+ #2
[ 97.937610] Hardware name: Dell Inc. Precision 7865 Tower/, BIOS 1.0.0 06/12/2022
[ 97.937611] Workqueue: events_unbound async_run_entry_fn
[ 97.937616] Call Trace:
[ 97.937617] <TASK>
[ 97.937619] dump_stack_lvl+0x49/0x63
[ 97.937624] dump_stack+0x10/0x16
[ 97.937626] ubsan_epilogue+0x9/0x3f
[ 97.937627] __ubsan_handle_out_of_bounds.cold+0x44/0x49
[ 97.937629] ? __scm_send+0x348/0x440
[ 97.937632] ? aq_vec_stop+0x72/0x80 [atlantic]
[ 97.937639] aq_nic_stop+0x1b6/0x1c0 [atlantic]
[ 97.937644] aq_suspend_common+0x88/0x90 [atlantic]
[ 97.937648] aq_pm_suspend_poweroff+0xe/0x20 [atlantic]
[ 97.937653] pci_pm_suspend+0x7e/0x1a0
[ 97.937655] ? pci_pm_suspend_noirq+0x2b0/0x2b0
[ 97.937657] dpm_run_callback+0x54/0x190
[ 97.937660] __device_suspend+0x14c/0x4d0
[ 97.937661] async_suspend+0x23/0x70
[ 97.937663] async_run_entry_fn+0x33/0x120
[ 97.937664] process_one_work+0x21f/0x3f0
[ 97.937666] worker_thread+0x4a/0x3c0
[ 97.937668] ? process_one_work+0x3f0/0x3f0
[ 97.937669] kthread+0xf0/0x120
[ 97.937671] ? kthread_complete_and_exit+0x20/0x20
[ 97.937672] ret_from_fork+0x22/0x30
[ 97.937676] </TASK>
v2. fixed "warning: variable 'aq_vec' set but not used"
v3. simplified a for loop
In the Linux kernel, the following vulnerability has been resolved:
btrfs: unset reloc control if transaction commit fails in prepare_to_relocate()
In btrfs_relocate_block_group(), the rc is allocated. Then
btrfs_relocate_block_group() calls
relocate_block_group()
prepare_to_relocate()
set_reloc_control()
that assigns rc to the variable fs_info->reloc_ctl. When
prepare_to_relocate() returns, it calls
btrfs_commit_transaction()
btrfs_start_dirty_block_groups()
btrfs_alloc_path()
kmem_cache_zalloc()
which may fail for example (or other errors could happen). When the
failure occurs, btrfs_relocate_block_group() detects the error and frees
rc and doesn't set fs_info->reloc_ctl to NULL. After that, in
btrfs_init_reloc_root(), rc is retrieved from fs_info->reloc_ctl and
then used, which may cause a use-after-free bug.
This possible bug can be triggered by calling btrfs_ioctl_balance()
before calling btrfs_ioctl_defrag().
To fix this possible bug, in prepare_to_relocate(), check if
btrfs_commit_transaction() fails. If the failure occurs,
unset_reloc_control() is called to set fs_info->reloc_ctl to NULL.
The error log in our fault-injection testing is shown as follows:
[ 58.751070] BUG: KASAN: use-after-free in btrfs_init_reloc_root+0x7ca/0x920 [btrfs]
...
[ 58.753577] Call Trace:
...
[ 58.755800] kasan_report+0x45/0x60
[ 58.756066] btrfs_init_reloc_root+0x7ca/0x920 [btrfs]
[ 58.757304] record_root_in_trans+0x792/0xa10 [btrfs]
[ 58.757748] btrfs_record_root_in_trans+0x463/0x4f0 [btrfs]
[ 58.758231] start_transaction+0x896/0x2950 [btrfs]
[ 58.758661] btrfs_defrag_root+0x250/0xc00 [btrfs]
[ 58.759083] btrfs_ioctl_defrag+0x467/0xa00 [btrfs]
[ 58.759513] btrfs_ioctl+0x3c95/0x114e0 [btrfs]
...
[ 58.768510] Allocated by task 23683:
[ 58.768777] ____kasan_kmalloc+0xb5/0xf0
[ 58.769069] __kmalloc+0x227/0x3d0
[ 58.769325] alloc_reloc_control+0x10a/0x3d0 [btrfs]
[ 58.769755] btrfs_relocate_block_group+0x7aa/0x1e20 [btrfs]
[ 58.770228] btrfs_relocate_chunk+0xf1/0x760 [btrfs]
[ 58.770655] __btrfs_balance+0x1326/0x1f10 [btrfs]
[ 58.771071] btrfs_balance+0x3150/0x3d30 [btrfs]
[ 58.771472] btrfs_ioctl_balance+0xd84/0x1410 [btrfs]
[ 58.771902] btrfs_ioctl+0x4caa/0x114e0 [btrfs]
...
[ 58.773337] Freed by task 23683:
...
[ 58.774815] kfree+0xda/0x2b0
[ 58.775038] free_reloc_control+0x1d6/0x220 [btrfs]
[ 58.775465] btrfs_relocate_block_group+0x115c/0x1e20 [btrfs]
[ 58.775944] btrfs_relocate_chunk+0xf1/0x760 [btrfs]
[ 58.776369] __btrfs_balance+0x1326/0x1f10 [btrfs]
[ 58.776784] btrfs_balance+0x3150/0x3d30 [btrfs]
[ 58.777185] btrfs_ioctl_balance+0xd84/0x1410 [btrfs]
[ 58.777621] btrfs_ioctl+0x4caa/0x114e0 [btrfs]
...
In the Linux kernel, the following vulnerability has been resolved:
drm/ttm: Fix dummy res NULL ptr deref bug
Check the bo->resource value before accessing the resource
mem_type.
v2: Fix commit description unwrapped warning
<log snip>
[ 40.191227][ T184] general protection fault, probably for non-canonical address 0xdffffc0000000002: 0000 [#1] SMP KASAN PTI
[ 40.192995][ T184] KASAN: null-ptr-deref in range [0x0000000000000010-0x0000000000000017]
[ 40.194411][ T184] CPU: 1 PID: 184 Comm: systemd-udevd Not tainted 5.19.0-rc4-00721-gb297c22b7070 #1
[ 40.196063][ T184] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.0-debian-1.16.0-4 04/01/2014
[ 40.199605][ T184] RIP: 0010:ttm_bo_validate+0x1b3/0x240 [ttm]
[ 40.200754][ T184] Code: e8 72 c5 ff ff 83 f8 b8 74 d4 85 c0 75 54 49 8b 9e 58 01 00 00 48 b8 00 00 00 00 00 fc ff df 48 8d 7b 10 48 89 fa 48 c1 ea 03 <0f> b6 04 02 84 c0 74 04 3c 03 7e 44 8b 53 10 31 c0 85 d2 0f 85 58
[ 40.203685][ T184] RSP: 0018:ffffc900006df0c8 EFLAGS: 00010202
[ 40.204630][ T184] RAX: dffffc0000000000 RBX: 0000000000000000 RCX: 1ffff1102f4bb71b
[ 40.205864][ T184] RDX: 0000000000000002 RSI: ffffc900006df208 RDI: 0000000000000010
[ 40.207102][ T184] RBP: 1ffff920000dbe1a R08: ffffc900006df208 R09: 0000000000000000
[ 40.208394][ T184] R10: ffff88817a5f0000 R11: 0000000000000001 R12: ffffc900006df110
[ 40.209692][ T184] R13: ffffc900006df0f0 R14: ffff88817a5db800 R15: ffffc900006df208
[ 40.210862][ T184] FS: 00007f6b1d16e8c0(0000) GS:ffff88839d700000(0000) knlGS:0000000000000000
[ 40.212250][ T184] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 40.213275][ T184] CR2: 000055a1001d4ff0 CR3: 00000001700f4000 CR4: 00000000000006e0
[ 40.214469][ T184] Call Trace:
[ 40.214974][ T184] <TASK>
[ 40.215438][ T184] ? ttm_bo_bounce_temp_buffer+0x140/0x140 [ttm]
[ 40.216572][ T184] ? mutex_spin_on_owner+0x240/0x240
[ 40.217456][ T184] ? drm_vma_offset_add+0xaa/0x100 [drm]
[ 40.218457][ T184] ttm_bo_init_reserved+0x3d6/0x540 [ttm]
[ 40.219410][ T184] ? shmem_get_inode+0x744/0x980
[ 40.220231][ T184] ttm_bo_init_validate+0xb1/0x200 [ttm]
[ 40.221172][ T184] ? bo_driver_evict_flags+0x340/0x340 [drm_vram_helper]
[ 40.222530][ T184] ? ttm_bo_init_reserved+0x540/0x540 [ttm]
[ 40.223643][ T184] ? __do_sys_finit_module+0x11a/0x1c0
[ 40.224654][ T184] ? __shmem_file_setup+0x102/0x280
[ 40.234764][ T184] drm_gem_vram_create+0x305/0x480 [drm_vram_helper]
[ 40.235766][ T184] ? bo_driver_evict_flags+0x340/0x340 [drm_vram_helper]
[ 40.236846][ T184] ? __kasan_slab_free+0x108/0x180
[ 40.237650][ T184] drm_gem_vram_fill_create_dumb+0x134/0x340 [drm_vram_helper]
[ 40.238864][ T184] ? local_pci_probe+0xdf/0x180
[ 40.239674][ T184] ? drmm_vram_helper_init+0x400/0x400 [drm_vram_helper]
[ 40.240826][ T184] drm_client_framebuffer_create+0x19c/0x400 [drm]
[ 40.241955][ T184] ? drm_client_buffer_delete+0x200/0x200 [drm]
[ 40.243001][ T184] ? drm_client_pick_crtcs+0x554/0xb80 [drm]
[ 40.244030][ T184] drm_fb_helper_generic_probe+0x23f/0x940 [drm_kms_helper]
[ 40.245226][ T184] ? __cond_resched+0x1c/0xc0
[ 40.245987][ T184] ? drm_fb_helper_memory_range_to_clip+0x180/0x180 [drm_kms_helper]
[ 40.247316][ T184] ? mutex_unlock+0x80/0x100
[ 40.248005][ T184] ? __mutex_unlock_slowpath+0x2c0/0x2c0
[ 40.249083][ T184] drm_fb_helper_single_fb_probe+0x907/0xf00 [drm_kms_helper]
[ 40.250314][ T184] ? drm_fb_helper_check_var+0x1180/0x1180 [drm_kms_helper]
[ 40.251540][ T184] ? __cond_resched+0x1c/0xc0
[ 40.252321][ T184] ? mutex_lock+0x9f/0x100
[ 40.253062][ T184] __drm_fb_helper_initial_config_and_unlock+0xb9/0x2c0 [drm_kms_helper]
[ 40.254394][ T184] drm_fbdev_client_hotplug+0x56f/0x840 [drm_kms_helper]
[ 40.255477][ T184] drm_fbdev_generic_setup+0x165/0x3c0 [drm_kms_helper]
[ 40.256607][ T184] bochs_pci_probe+0x6b7/0x900 [bochs]
[
---truncated---
In the Linux kernel, the following vulnerability has been resolved:
BPF: Fix potential bad pointer dereference in bpf_sys_bpf()
The bpf_sys_bpf() helper function allows an eBPF program to load another
eBPF program from within the kernel. In this case the argument union
bpf_attr pointer (as well as the insns and license pointers inside) is a
kernel address instead of a userspace address (which is the case of a
usual bpf() syscall). To make the memory copying process in the syscall
work in both cases, bpfptr_t was introduced to wrap around the pointer
and distinguish its origin. Specifically, when copying memory contents
from a bpfptr_t, a copy_from_user() is performed in case of a userspace
address and a memcpy() is performed for a kernel address.
This can lead to problems because the in-kernel pointer is never checked
for validity. The problem happens when an eBPF syscall program tries to
call bpf_sys_bpf() to load a program but provides a bad insns pointer --
say 0xdeadbeef -- in the bpf_attr union. The helper calls __sys_bpf()
which would then call bpf_prog_load() to load the program.
bpf_prog_load() is responsible for copying the eBPF instructions to the
newly allocated memory for the program; it creates a kernel bpfptr_t for
insns and invokes copy_from_bpfptr(). Internally, all bpfptr_t
operations are backed by the corresponding sockptr_t operations, which
performs direct memcpy() on kernel pointers for copy_from/strncpy_from
operations. Therefore, the code is always happy to dereference the bad
pointer to trigger a un-handle-able page fault and in turn an oops.
However, this is not supposed to happen because at that point the eBPF
program is already verified and should not cause a memory error.
Sample KASAN trace:
[ 25.685056][ T228] ==================================================================
[ 25.685680][ T228] BUG: KASAN: user-memory-access in copy_from_bpfptr+0x21/0x30
[ 25.686210][ T228] Read of size 80 at addr 00000000deadbeef by task poc/228
[ 25.686732][ T228]
[ 25.686893][ T228] CPU: 3 PID: 228 Comm: poc Not tainted 5.19.0-rc7 #7
[ 25.687375][ T228] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS d55cb5a 04/01/2014
[ 25.687991][ T228] Call Trace:
[ 25.688223][ T228] <TASK>
[ 25.688429][ T228] dump_stack_lvl+0x73/0x9e
[ 25.688747][ T228] print_report+0xea/0x200
[ 25.689061][ T228] ? copy_from_bpfptr+0x21/0x30
[ 25.689401][ T228] ? _printk+0x54/0x6e
[ 25.689693][ T228] ? _raw_spin_lock_irqsave+0x70/0xd0
[ 25.690071][ T228] ? copy_from_bpfptr+0x21/0x30
[ 25.690412][ T228] kasan_report+0xb5/0xe0
[ 25.690716][ T228] ? copy_from_bpfptr+0x21/0x30
[ 25.691059][ T228] kasan_check_range+0x2bd/0x2e0
[ 25.691405][ T228] ? copy_from_bpfptr+0x21/0x30
[ 25.691734][ T228] memcpy+0x25/0x60
[ 25.692000][ T228] copy_from_bpfptr+0x21/0x30
[ 25.692328][ T228] bpf_prog_load+0x604/0x9e0
[ 25.692653][ T228] ? cap_capable+0xb4/0xe0
[ 25.692956][ T228] ? security_capable+0x4f/0x70
[ 25.693324][ T228] __sys_bpf+0x3af/0x580
[ 25.693635][ T228] bpf_sys_bpf+0x45/0x240
[ 25.693937][ T228] bpf_prog_f0ec79a5a3caca46_bpf_func1+0xa2/0xbd
[ 25.694394][ T228] bpf_prog_run_pin_on_cpu+0x2f/0xb0
[ 25.694756][ T228] bpf_prog_test_run_syscall+0x146/0x1c0
[ 25.695144][ T228] bpf_prog_test_run+0x172/0x190
[ 25.695487][ T228] __sys_bpf+0x2c5/0x580
[ 25.695776][ T228] __x64_sys_bpf+0x3a/0x50
[ 25.696084][ T228] do_syscall_64+0x60/0x90
[ 25.696393][ T228] ? fpregs_assert_state_consistent+0x50/0x60
[ 25.696815][ T228] ? exit_to_user_mode_prepare+0x36/0xa0
[ 25.697202][ T228] ? syscall_exit_to_user_mode+0x20/0x40
[ 25.697586][ T228] ? do_syscall_64+0x6e/0x90
[ 25.697899][ T228] entry_SYSCALL_64_after_hwframe+0x63/0xcd
[ 25.698312][ T228] RIP: 0033:0x7f6d543fb759
[ 25.698624][ T228] Code: 08 5b 89 e8 5d c3 66 2e 0f 1f 84 00 00 00 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d
---truncated---
In the Linux kernel, the following vulnerability has been resolved:
mptcp: do not queue data on closed subflows
Dipanjan reported a syzbot splat at close time:
WARNING: CPU: 1 PID: 10818 at net/ipv4/af_inet.c:153
inet_sock_destruct+0x6d0/0x8e0 net/ipv4/af_inet.c:153
Modules linked in: uio_ivshmem(OE) uio(E)
CPU: 1 PID: 10818 Comm: kworker/1:16 Tainted: G OE
5.19.0-rc6-g2eae0556bb9d #2
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS
1.13.0-1ubuntu1.1 04/01/2014
Workqueue: events mptcp_worker
RIP: 0010:inet_sock_destruct+0x6d0/0x8e0 net/ipv4/af_inet.c:153
Code: 21 02 00 00 41 8b 9c 24 28 02 00 00 e9 07 ff ff ff e8 34 4d 91
f9 89 ee 4c 89 e7 e8 4a 47 60 ff e9 a6 fc ff ff e8 20 4d 91 f9 <0f> 0b
e9 84 fe ff ff e8 14 4d 91 f9 0f 0b e9 d4 fd ff ff e8 08 4d
RSP: 0018:ffffc9001b35fa78 EFLAGS: 00010246
RAX: 0000000000000000 RBX: 00000000002879d0 RCX: ffff8881326f3b00
RDX: 0000000000000000 RSI: ffff8881326f3b00 RDI: 0000000000000002
RBP: ffff888179662674 R08: ffffffff87e983a0 R09: 0000000000000000
R10: 0000000000000005 R11: 00000000000004ea R12: ffff888179662400
R13: ffff888179662428 R14: 0000000000000001 R15: ffff88817e38e258
FS: 0000000000000000(0000) GS:ffff8881f5f00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000020007bc0 CR3: 0000000179592000 CR4: 0000000000150ee0
Call Trace:
<TASK>
__sk_destruct+0x4f/0x8e0 net/core/sock.c:2067
sk_destruct+0xbd/0xe0 net/core/sock.c:2112
__sk_free+0xef/0x3d0 net/core/sock.c:2123
sk_free+0x78/0xa0 net/core/sock.c:2134
sock_put include/net/sock.h:1927 [inline]
__mptcp_close_ssk+0x50f/0x780 net/mptcp/protocol.c:2351
__mptcp_destroy_sock+0x332/0x760 net/mptcp/protocol.c:2828
mptcp_worker+0x5d2/0xc90 net/mptcp/protocol.c:2586
process_one_work+0x9cc/0x1650 kernel/workqueue.c:2289
worker_thread+0x623/0x1070 kernel/workqueue.c:2436
kthread+0x2e9/0x3a0 kernel/kthread.c:376
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:302
</TASK>
The root cause of the problem is that an mptcp-level (re)transmit can
race with mptcp_close() and the packet scheduler checks the subflow
state before acquiring the socket lock: we can try to (re)transmit on
an already closed ssk.
Fix the issue checking again the subflow socket status under the
subflow socket lock protection. Additionally add the missing check
for the fallback-to-tcp case.