| CVE |
Vendors |
Products |
Updated |
CVSS v3.1 |
| In the Linux kernel, the following vulnerability has been resolved:
mptcp: use the workqueue to destroy unaccepted sockets
Christoph reported a UaF at token lookup time after having
refactored the passive socket initialization part:
BUG: KASAN: use-after-free in __token_bucket_busy+0x253/0x260
Read of size 4 at addr ffff88810698d5b0 by task syz-executor653/3198
CPU: 1 PID: 3198 Comm: syz-executor653 Not tainted 6.2.0-rc59af4eaa31c1f6c00c8f1e448ed99a45c66340dd5 #6
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014
Call Trace:
<TASK>
dump_stack_lvl+0x6e/0x91
print_report+0x16a/0x46f
kasan_report+0xad/0x130
__token_bucket_busy+0x253/0x260
mptcp_token_new_connect+0x13d/0x490
mptcp_connect+0x4ed/0x860
__inet_stream_connect+0x80e/0xd90
tcp_sendmsg_fastopen+0x3ce/0x710
mptcp_sendmsg+0xff1/0x1a20
inet_sendmsg+0x11d/0x140
__sys_sendto+0x405/0x490
__x64_sys_sendto+0xdc/0x1b0
do_syscall_64+0x3b/0x90
entry_SYSCALL_64_after_hwframe+0x72/0xdc
We need to properly clean-up all the paired MPTCP-level
resources and be sure to release the msk last, even when
the unaccepted subflow is destroyed by the TCP internals
via inet_child_forget().
We can re-use the existing MPTCP_WORK_CLOSE_SUBFLOW infra,
explicitly checking that for the critical scenario: the
closed subflow is the MPC one, the msk is not accepted and
eventually going through full cleanup.
With such change, __mptcp_destroy_sock() is always called
on msk sockets, even on accepted ones. We don't need anymore
to transiently drop one sk reference at msk clone time.
Please note this commit depends on the parent one:
mptcp: refactor passive socket initialization |
| In the Linux kernel, the following vulnerability has been resolved:
perf/x86/amd/core: Always clear status for idx
The variable 'status' (which contains the unhandled overflow bits) is
not being properly masked in some cases, displaying the following
warning:
WARNING: CPU: 156 PID: 475601 at arch/x86/events/amd/core.c:972 amd_pmu_v2_handle_irq+0x216/0x270
This seems to be happening because the loop is being continued before
the status bit being unset, in case x86_perf_event_set_period()
returns 0. This is also causing an inconsistency because the "handled"
counter is incremented, but the status bit is not cleaned.
Move the bit cleaning together above, together when the "handled"
counter is incremented. |
| In the Linux kernel, the following vulnerability has been resolved:
drm/amdgpu: fix ttm_bo calltrace warning in psp_hw_fini
The call trace occurs when the amdgpu is removed after
the mode1 reset. During mode1 reset, from suspend to resume,
there is no need to reinitialize the ta firmware buffer
which caused the bo pin_count increase redundantly.
[ 489.885525] Call Trace:
[ 489.885525] <TASK>
[ 489.885526] amdttm_bo_put+0x34/0x50 [amdttm]
[ 489.885529] amdgpu_bo_free_kernel+0xe8/0x130 [amdgpu]
[ 489.885620] psp_free_shared_bufs+0xb7/0x150 [amdgpu]
[ 489.885720] psp_hw_fini+0xce/0x170 [amdgpu]
[ 489.885815] amdgpu_device_fini_hw+0x2ff/0x413 [amdgpu]
[ 489.885960] ? blocking_notifier_chain_unregister+0x56/0xb0
[ 489.885962] amdgpu_driver_unload_kms+0x51/0x60 [amdgpu]
[ 489.886049] amdgpu_pci_remove+0x5a/0x140 [amdgpu]
[ 489.886132] ? __pm_runtime_resume+0x60/0x90
[ 489.886134] pci_device_remove+0x3e/0xb0
[ 489.886135] __device_release_driver+0x1ab/0x2a0
[ 489.886137] driver_detach+0xf3/0x140
[ 489.886138] bus_remove_driver+0x6c/0xf0
[ 489.886140] driver_unregister+0x31/0x60
[ 489.886141] pci_unregister_driver+0x40/0x90
[ 489.886142] amdgpu_exit+0x15/0x451 [amdgpu] |
| In the Linux kernel, the following vulnerability has been resolved:
ftrace: Fix invalid address access in lookup_rec() when index is 0
KASAN reported follow problem:
BUG: KASAN: use-after-free in lookup_rec
Read of size 8 at addr ffff000199270ff0 by task modprobe
CPU: 2 Comm: modprobe
Call trace:
kasan_report
__asan_load8
lookup_rec
ftrace_location
arch_check_ftrace_location
check_kprobe_address_safe
register_kprobe
When checking pg->records[pg->index - 1].ip in lookup_rec(), it can get a
pg which is newly added to ftrace_pages_start in ftrace_process_locs().
Before the first pg->index++, index is 0 and accessing pg->records[-1].ip
will cause this problem.
Don't check the ip when pg->index is 0. |
| In the Linux kernel, the following vulnerability has been resolved:
drm/amd/display: fix shift-out-of-bounds in CalculateVMAndRowBytes
[WHY]
When PTEBufferSizeInRequests is zero, UBSAN reports the following
warning because dml_log2 returns an unexpected negative value:
shift exponent 4294966273 is too large for 32-bit type 'int'
[HOW]
In the case PTEBufferSizeInRequests is zero, skip the dml_log2() and
assign the result directly. |
| In the Linux kernel, the following vulnerability has been resolved:
scsi: scsi_dh_alua: Fix memleak for 'qdata' in alua_activate()
If alua_rtpg_queue() failed from alua_activate(), then 'qdata' is not
freed, which will cause following memleak:
unreferenced object 0xffff88810b2c6980 (size 32):
comm "kworker/u16:2", pid 635322, jiffies 4355801099 (age 1216426.076s)
hex dump (first 32 bytes):
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
40 39 24 c1 ff ff ff ff 00 f8 ea 0a 81 88 ff ff @9$.............
backtrace:
[<0000000098f3a26d>] alua_activate+0xb0/0x320
[<000000003b529641>] scsi_dh_activate+0xb2/0x140
[<000000007b296db3>] activate_path_work+0xc6/0xe0 [dm_multipath]
[<000000007adc9ace>] process_one_work+0x3c5/0x730
[<00000000c457a985>] worker_thread+0x93/0x650
[<00000000cb80e628>] kthread+0x1ba/0x210
[<00000000a1e61077>] ret_from_fork+0x22/0x30
Fix the problem by freeing 'qdata' in error path. |
| In the Linux kernel, the following vulnerability has been resolved:
net/mlx5: Fix steering rules cleanup
vport's mc, uc and multicast rules are not deleted in teardown path when
EEH happens. Since the vport's promisc settings(uc, mc and all) in
firmware are reset after EEH, mlx5 driver will try to delete the above
rules in the initialization path. This cause kernel crash because these
software rules are no longer valid.
Fix by nullifying these rules right after delete to avoid accessing any dangling
pointers.
Call Trace:
__list_del_entry_valid+0xcc/0x100 (unreliable)
tree_put_node+0xf4/0x1b0 [mlx5_core]
tree_remove_node+0x30/0x70 [mlx5_core]
mlx5_del_flow_rules+0x14c/0x1f0 [mlx5_core]
esw_apply_vport_rx_mode+0x10c/0x200 [mlx5_core]
esw_update_vport_rx_mode+0xb4/0x180 [mlx5_core]
esw_vport_change_handle_locked+0x1ec/0x230 [mlx5_core]
esw_enable_vport+0x130/0x260 [mlx5_core]
mlx5_eswitch_enable_sriov+0x2a0/0x2f0 [mlx5_core]
mlx5_device_enable_sriov+0x74/0x440 [mlx5_core]
mlx5_load_one+0x114c/0x1550 [mlx5_core]
mlx5_pci_resume+0x68/0xf0 [mlx5_core]
eeh_report_resume+0x1a4/0x230
eeh_pe_dev_traverse+0x98/0x170
eeh_handle_normal_event+0x3e4/0x640
eeh_handle_event+0x4c/0x370
eeh_event_handler+0x14c/0x210
kthread+0x168/0x1b0
ret_from_kernel_thread+0x5c/0x84 |
| In the Linux kernel, the following vulnerability has been resolved:
xsk: Add missing overflow check in xdp_umem_reg
The number of chunks can overflow u32. Make sure to return -EINVAL on
overflow. Also remove a redundant u32 cast assigning umem->npgs. |
| In the Linux kernel, the following vulnerability has been resolved:
ocfs2: fix data corruption after failed write
When buffered write fails to copy data into underlying page cache page,
ocfs2_write_end_nolock() just zeroes out and dirties the page. This can
leave dirty page beyond EOF and if page writeback tries to write this page
before write succeeds and expands i_size, page gets into inconsistent
state where page dirty bit is clear but buffer dirty bits stay set
resulting in page data never getting written and so data copied to the
page is lost. Fix the problem by invalidating page beyond EOF after
failed write. |
| In the Linux kernel, the following vulnerability has been resolved:
vp_vdpa: fix the crash in hot unplug with vp_vdpa
While unplugging the vp_vdpa device, it triggers a kernel panic
The root cause is: vdpa_mgmtdev_unregister() will accesses modern
devices which will cause a use after free.
So need to change the sequence in vp_vdpa_remove
[ 195.003359] BUG: unable to handle page fault for address: ff4e8beb80199014
[ 195.004012] #PF: supervisor read access in kernel mode
[ 195.004486] #PF: error_code(0x0000) - not-present page
[ 195.004960] PGD 100000067 P4D 1001b6067 PUD 1001b7067 PMD 1001b8067 PTE 0
[ 195.005578] Oops: 0000 1 PREEMPT SMP PTI
[ 195.005968] CPU: 13 PID: 164 Comm: kworker/u56:10 Kdump: loaded Not tainted 5.14.0-252.el9.x86_64 #1
[ 195.006792] Hardware name: Red Hat KVM/RHEL, BIOS edk2-20221207gitfff6d81270b5-2.el9 unknown
[ 195.007556] Workqueue: kacpi_hotplug acpi_hotplug_work_fn
[ 195.008059] RIP: 0010:ioread8+0x31/0x80
[ 195.008418] Code: 77 28 48 81 ff 00 00 01 00 76 0b 89 fa ec 0f b6 c0 c3 cc cc cc cc 8b 15 ad 72 93 01 b8 ff 00 00 00 85 d2 75 0f c3 cc cc cc cc <8a> 07 0f b6 c0 c3 cc cc cc cc 83 ea 01 48 83 ec 08 48 89 fe 48 c7
[ 195.010104] RSP: 0018:ff4e8beb8067bab8 EFLAGS: 00010292
[ 195.010584] RAX: ffffffffc05834a0 RBX: ffffffffc05843c0 RCX: ff4e8beb8067bae0
[ 195.011233] RDX: ff1bcbd580f88000 RSI: 0000000000000246 RDI: ff4e8beb80199014
[ 195.011881] RBP: ff1bcbd587e39000 R08: ffffffff916fa2d0 R09: ff4e8beb8067ba68
[ 195.012527] R10: 000000000000001c R11: 0000000000000000 R12: ff1bcbd5a3de9120
[ 195.013179] R13: ffffffffc062d000 R14: 0000000000000080 R15: ff1bcbe402bc7805
[ 195.013826] FS: 0000000000000000(0000) GS:ff1bcbe402740000(0000) knlGS:0000000000000000
[ 195.014564] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 195.015093] CR2: ff4e8beb80199014 CR3: 0000000107dea002 CR4: 0000000000771ee0
[ 195.015741] PKRU: 55555554
[ 195.016001] Call Trace:
[ 195.016233] <TASK>
[ 195.016434] vp_modern_get_status+0x12/0x20
[ 195.016823] vp_vdpa_reset+0x1b/0x50 [vp_vdpa]
[ 195.017238] virtio_vdpa_reset+0x3c/0x48 [virtio_vdpa]
[ 195.017709] remove_vq_common+0x1f/0x3a0 [virtio_net]
[ 195.018178] virtnet_remove+0x5d/0x70 [virtio_net]
[ 195.018618] virtio_dev_remove+0x3d/0x90
[ 195.018986] device_release_driver_internal+0x1aa/0x230
[ 195.019466] bus_remove_device+0xd8/0x150
[ 195.019841] device_del+0x18b/0x3f0
[ 195.020167] ? kernfs_find_ns+0x35/0xd0
[ 195.020526] device_unregister+0x13/0x60
[ 195.020894] unregister_virtio_device+0x11/0x20
[ 195.021311] device_release_driver_internal+0x1aa/0x230
[ 195.021790] bus_remove_device+0xd8/0x150
[ 195.022162] device_del+0x18b/0x3f0
[ 195.022487] device_unregister+0x13/0x60
[ 195.022852] ? vdpa_dev_remove+0x30/0x30 [vdpa]
[ 195.023270] vp_vdpa_dev_del+0x12/0x20 [vp_vdpa]
[ 195.023694] vdpa_match_remove+0x2b/0x40 [vdpa]
[ 195.024115] bus_for_each_dev+0x78/0xc0
[ 195.024471] vdpa_mgmtdev_unregister+0x65/0x80 [vdpa]
[ 195.024937] vp_vdpa_remove+0x23/0x40 [vp_vdpa]
[ 195.025353] pci_device_remove+0x36/0xa0
[ 195.025719] device_release_driver_internal+0x1aa/0x230
[ 195.026201] pci_stop_bus_device+0x6c/0x90
[ 195.026580] pci_stop_and_remove_bus_device+0xe/0x20
[ 195.027039] disable_slot+0x49/0x90
[ 195.027366] acpiphp_disable_and_eject_slot+0x15/0x90
[ 195.027832] hotplug_event+0xea/0x210
[ 195.028171] ? hotplug_event+0x210/0x210
[ 195.028535] acpiphp_hotplug_notify+0x22/0x80
[ 195.028942] ? hotplug_event+0x210/0x210
[ 195.029303] acpi_device_hotplug+0x8a/0x1d0
[ 195.029690] acpi_hotplug_work_fn+0x1a/0x30
[ 195.030077] process_one_work+0x1e8/0x3c0
[ 195.030451] worker_thread+0x50/0x3b0
[ 195.030791] ? rescuer_thread+0x3a0/0x3a0
[ 195.031165] kthread+0xd9/0x100
[ 195.031459] ? kthread_complete_and_exit+0x20/0x20
[ 195.031899] ret_from_fork+0x22/0x30
[ 195.032233] </TASK> |
| In the Linux kernel, the following vulnerability has been resolved:
drm/amd/display: prevent hang on link training fail
[Why]
When link training fails, the phy clock will be disabled. However, in
enable_streams, it is assumed that link training succeeded and the
mux selects the phy clock, causing a hang when a register write is made.
[How]
When enable_stream is hit, check if link training failed. If it did, fall
back to the ref clock to avoid a hang and keep the system in a recoverable
state. |
| In the Linux kernel, the following vulnerability has been resolved:
drm/xe: Use local fence in error path of xe_migrate_clear
The intent of the error path in xe_migrate_clear is to wait on locally
generated fence and then return. The code is waiting on m->fence which
could be the local fence but this is only stable under the job mutex
leading to a possible UAF. Fix code to wait on local fence.
(cherry picked from commit 762b7e95362170b3e13a8704f38d5e47eca4ba74) |
| In the Linux kernel, the following vulnerability has been resolved:
net: use sock_gen_put() when sk_state is TCP_TIME_WAIT
It is possible for a pointer of type struct inet_timewait_sock to be
returned from the functions __inet_lookup_established() and
__inet6_lookup_established(). This can cause a crash when the
returned pointer is of type struct inet_timewait_sock and
sock_put() is called on it. The following is a crash call stack that
shows sk->sk_wmem_alloc being accessed in sk_free() during the call to
sock_put() on a struct inet_timewait_sock pointer. To avoid this issue,
use sock_gen_put() instead of sock_put() when sk->sk_state
is TCP_TIME_WAIT.
mrdump.ko ipanic() + 120
vmlinux notifier_call_chain(nr_to_call=-1, nr_calls=0) + 132
vmlinux atomic_notifier_call_chain(val=0) + 56
vmlinux panic() + 344
vmlinux add_taint() + 164
vmlinux end_report() + 136
vmlinux kasan_report(size=0) + 236
vmlinux report_tag_fault() + 16
vmlinux do_tag_recovery() + 16
vmlinux __do_kernel_fault() + 88
vmlinux do_bad_area() + 28
vmlinux do_tag_check_fault() + 60
vmlinux do_mem_abort() + 80
vmlinux el1_abort() + 56
vmlinux el1h_64_sync_handler() + 124
vmlinux > 0xFFFFFFC080011294()
vmlinux __lse_atomic_fetch_add_release(v=0xF2FFFF82A896087C)
vmlinux __lse_atomic_fetch_sub_release(v=0xF2FFFF82A896087C)
vmlinux arch_atomic_fetch_sub_release(i=1, v=0xF2FFFF82A896087C)
+ 8
vmlinux raw_atomic_fetch_sub_release(i=1, v=0xF2FFFF82A896087C)
+ 8
vmlinux atomic_fetch_sub_release(i=1, v=0xF2FFFF82A896087C) + 8
vmlinux __refcount_sub_and_test(i=1, r=0xF2FFFF82A896087C,
oldp=0) + 8
vmlinux __refcount_dec_and_test(r=0xF2FFFF82A896087C, oldp=0) + 8
vmlinux refcount_dec_and_test(r=0xF2FFFF82A896087C) + 8
vmlinux sk_free(sk=0xF2FFFF82A8960700) + 28
vmlinux sock_put() + 48
vmlinux tcp6_check_fraglist_gro() + 236
vmlinux tcp6_gro_receive() + 624
vmlinux ipv6_gro_receive() + 912
vmlinux dev_gro_receive() + 1116
vmlinux napi_gro_receive() + 196
ccmni.ko ccmni_rx_callback() + 208
ccmni.ko ccmni_queue_recv_skb() + 388
ccci_dpmaif.ko dpmaif_rxq_push_thread() + 1088
vmlinux kthread() + 268
vmlinux 0xFFFFFFC08001F30C() |
| In the Linux kernel, the following vulnerability has been resolved:
drm/xe/userptr: fix notifier vs folio deadlock
User is reporting what smells like notifier vs folio deadlock, where
migrate_pages_batch() on core kernel side is holding folio lock(s) and
then interacting with the mappings of it, however those mappings are
tied to some userptr, which means calling into the notifier callback and
grabbing the notifier lock. With perfect timing it looks possible that
the pages we pulled from the hmm fault can get sniped by
migrate_pages_batch() at the same time that we are holding the notifier
lock to mark the pages as accessed/dirty, but at this point we also want
to grab the folio locks(s) to mark them as dirty, but if they are
contended from notifier/migrate_pages_batch side then we deadlock since
folio lock won't be dropped until we drop the notifier lock.
Fortunately the mark_page_accessed/dirty is not really needed in the
first place it seems and should have already been done by hmm fault, so
just remove it.
(cherry picked from commit bd7c0cb695e87c0e43247be8196b4919edbe0e85) |
| In the Linux kernel, the following vulnerability has been resolved:
mtd: inftlcore: Add error check for inftl_read_oob()
In INFTL_findwriteunit(), the return value of inftl_read_oob()
need to be checked. A proper implementation can be
found in INFTL_deleteblock(). The status will be set as
SECTOR_IGNORE to break from the while-loop correctly
if the inftl_read_oob() fails. |
| In the Linux kernel, the following vulnerability has been resolved:
RDMA/core: Silence oversized kvmalloc() warning
syzkaller triggered an oversized kvmalloc() warning.
Silence it by adding __GFP_NOWARN.
syzkaller log:
WARNING: CPU: 7 PID: 518 at mm/util.c:665 __kvmalloc_node_noprof+0x175/0x180
CPU: 7 UID: 0 PID: 518 Comm: c_repro Not tainted 6.11.0-rc6+ #6
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014
RIP: 0010:__kvmalloc_node_noprof+0x175/0x180
RSP: 0018:ffffc90001e67c10 EFLAGS: 00010246
RAX: 0000000000000100 RBX: 0000000000000400 RCX: ffffffff8149d46b
RDX: 0000000000000000 RSI: ffff8881030fae80 RDI: 0000000000000002
RBP: 000000712c800000 R08: 0000000000000100 R09: 0000000000000000
R10: ffffc90001e67c10 R11: 0030ae0601000000 R12: 0000000000000000
R13: 0000000000000000 R14: 00000000ffffffff R15: 0000000000000000
FS: 00007fde79159740(0000) GS:ffff88813bdc0000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000020000180 CR3: 0000000105eb4005 CR4: 00000000003706b0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
ib_umem_odp_get+0x1f6/0x390
mlx5_ib_reg_user_mr+0x1e8/0x450
ib_uverbs_reg_mr+0x28b/0x440
ib_uverbs_write+0x7d3/0xa30
vfs_write+0x1ac/0x6c0
ksys_write+0x134/0x170
? __sanitizer_cov_trace_pc+0x1c/0x50
do_syscall_64+0x50/0x110
entry_SYSCALL_64_after_hwframe+0x76/0x7e |
| In the Linux kernel, the following vulnerability has been resolved:
mlxbf-bootctl: use sysfs_emit_at() in secure_boot_fuse_state_show()
A warning is seen when running the latest kernel on a BlueField SOC:
[251.512704] ------------[ cut here ]------------
[251.512711] invalid sysfs_emit: buf:0000000003aa32ae
[251.512720] WARNING: CPU: 1 PID: 705264 at fs/sysfs/file.c:767 sysfs_emit+0xac/0xc8
The warning is triggered because the mlxbf-bootctl driver invokes
"sysfs_emit()" with a buffer pointer that is not aligned to the
start of the page. The driver should instead use "sysfs_emit_at()"
to support non-zero offsets into the destination buffer. |
| In the Linux kernel, the following vulnerability has been resolved:
net: dsa: mv88e6xxx: fix -ENOENT when deleting VLANs and MST is unsupported
Russell King reports that on the ZII dev rev B, deleting a bridge VLAN
from a user port fails with -ENOENT:
https://lore.kernel.org/netdev/Z_lQXNP0s5-IiJzd@shell.armlinux.org.uk/
This comes from mv88e6xxx_port_vlan_leave() -> mv88e6xxx_mst_put(),
which tries to find an MST entry in &chip->msts associated with the SID,
but fails and returns -ENOENT as such.
But we know that this chip does not support MST at all, so that is not
surprising. The question is why does the guard in mv88e6xxx_mst_put()
not exit early:
if (!sid)
return 0;
And the answer seems to be simple: the sid comes from vlan.sid which
supposedly was previously populated by mv88e6xxx_vtu_get().
But some chip->info->ops->vtu_getnext() implementations do not populate
vlan.sid, for example see mv88e6185_g1_vtu_getnext(). In that case,
later in mv88e6xxx_port_vlan_leave() we are using a garbage sid which is
just residual stack memory.
Testing for sid == 0 covers all cases of a non-bridge VLAN or a bridge
VLAN mapped to the default MSTI. For some chips, SID 0 is valid and
installed by mv88e6xxx_stu_setup(). A chip which does not support the
STU would implicitly only support mapping all VLANs to the default MSTI,
so although SID 0 is not valid, it would be sufficient, if we were to
zero-initialize the vlan structure, to fix the bug, due to the
coincidence that a test for vlan.sid == 0 already exists and leads to
the same (correct) behavior.
Another option which would be sufficient would be to add a test for
mv88e6xxx_has_stu() inside mv88e6xxx_mst_put(), symmetric to the one
which already exists in mv88e6xxx_mst_get(). But that placement means
the caller will have to dereference vlan.sid, which means it will access
uninitialized memory, which is not nice even if it ignores it later.
So we end up making both modifications, in order to not rely just on the
sid == 0 coincidence, but also to avoid having uninitialized structure
fields which might get temporarily accessed. |
| In the Linux kernel, the following vulnerability has been resolved:
net: dsa: clean up FDB, MDB, VLAN entries on unbind
As explained in many places such as commit b117e1e8a86d ("net: dsa:
delete dsa_legacy_fdb_add and dsa_legacy_fdb_del"), DSA is written given
the assumption that higher layers have balanced additions/deletions.
As such, it only makes sense to be extremely vocal when those
assumptions are violated and the driver unbinds with entries still
present.
But Ido Schimmel points out a very simple situation where that is wrong:
https://lore.kernel.org/netdev/ZDazSM5UsPPjQuKr@shredder/
(also briefly discussed by me in the aforementioned commit).
Basically, while the bridge bypass operations are not something that DSA
explicitly documents, and for the majority of DSA drivers this API
simply causes them to go to promiscuous mode, that isn't the case for
all drivers. Some have the necessary requirements for bridge bypass
operations to do something useful - see dsa_switch_supports_uc_filtering().
Although in tools/testing/selftests/net/forwarding/local_termination.sh,
we made an effort to popularize better mechanisms to manage address
filters on DSA interfaces from user space - namely macvlan for unicast,
and setsockopt(IP_ADD_MEMBERSHIP) - through mtools - for multicast, the
fact is that 'bridge fdb add ... self static local' also exists as
kernel UAPI, and might be useful to someone, even if only for a quick
hack.
It seems counter-productive to block that path by implementing shim
.ndo_fdb_add and .ndo_fdb_del operations which just return -EOPNOTSUPP
in order to prevent the ndo_dflt_fdb_add() and ndo_dflt_fdb_del() from
running, although we could do that.
Accepting that cleanup is necessary seems to be the only option.
Especially since we appear to be coming back at this from a different
angle as well. Russell King is noticing that the WARN_ON() triggers even
for VLANs:
https://lore.kernel.org/netdev/Z_li8Bj8bD4-BYKQ@shell.armlinux.org.uk/
What happens in the bug report above is that dsa_port_do_vlan_del() fails,
then the VLAN entry lingers on, and then we warn on unbind and leak it.
This is not a straight revert of the blamed commit, but we now add an
informational print to the kernel log (to still have a way to see
that bugs exist), and some extra comments gathered from past years'
experience, to justify the logic. |
| In the Linux kernel, the following vulnerability has been resolved:
ovl: don't allow datadir only
In theory overlayfs could support upper layer directly referring to a data
layer, but there's no current use case for this.
Originally, when data-only layers were introduced, this wasn't allowed,
only introduced by the "datadir+" feature, but without actually handling
this case, resulting in an Oops.
Fix by disallowing datadir without lowerdir. |
