| CVE |
Vendors |
Products |
Updated |
CVSS v3.1 |
| In the Linux kernel, the following vulnerability has been resolved:
fs/ntfs3: Validate BOOT record_size
When the NTFS BOOT record_size field < 0, it represents a
shift value. However, there is no sanity check on the shift result
and the sbi->record_bits calculation through blksize_bits() assumes
the size always > 256, which could lead to NPD while mounting a
malformed NTFS image.
[ 318.675159] BUG: kernel NULL pointer dereference, address: 0000000000000158
[ 318.675682] #PF: supervisor read access in kernel mode
[ 318.675869] #PF: error_code(0x0000) - not-present page
[ 318.676246] PGD 0 P4D 0
[ 318.676502] Oops: 0000 [#1] PREEMPT SMP NOPTI
[ 318.676934] CPU: 0 PID: 259 Comm: mount Not tainted 5.19.0 #5
[ 318.677289] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.14.0-0-g155821a1990b-prebuilt.qemu.org 04/01/2014
[ 318.678136] RIP: 0010:ni_find_attr+0x2d/0x1c0
[ 318.678656] Code: 89 ca 4d 89 c7 41 56 41 55 41 54 41 89 cc 55 48 89 fd 53 48 89 d3 48 83 ec 20 65 48 8b 04 25 28 00 00 00 48 89 44 24 180
[ 318.679848] RSP: 0018:ffffa6c8c0297bd8 EFLAGS: 00000246
[ 318.680104] RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000080
[ 318.680790] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
[ 318.681679] RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
[ 318.682577] R10: 0000000000000000 R11: 0000000000000005 R12: 0000000000000080
[ 318.683015] R13: ffff8d5582e68400 R14: 0000000000000100 R15: 0000000000000000
[ 318.683618] FS: 00007fd9e1c81e40(0000) GS:ffff8d55fdc00000(0000) knlGS:0000000000000000
[ 318.684280] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 318.684651] CR2: 0000000000000158 CR3: 0000000002e1a000 CR4: 00000000000006f0
[ 318.685623] Call Trace:
[ 318.686607] <TASK>
[ 318.686872] ? ntfs_alloc_inode+0x1a/0x60
[ 318.687235] attr_load_runs_vcn+0x2b/0xa0
[ 318.687468] mi_read+0xbb/0x250
[ 318.687576] ntfs_iget5+0x114/0xd90
[ 318.687750] ntfs_fill_super+0x588/0x11b0
[ 318.687953] ? put_ntfs+0x130/0x130
[ 318.688065] ? snprintf+0x49/0x70
[ 318.688164] ? put_ntfs+0x130/0x130
[ 318.688256] get_tree_bdev+0x16a/0x260
[ 318.688407] vfs_get_tree+0x20/0xb0
[ 318.688519] path_mount+0x2dc/0x9b0
[ 318.688877] do_mount+0x74/0x90
[ 318.689142] __x64_sys_mount+0x89/0xd0
[ 318.689636] do_syscall_64+0x3b/0x90
[ 318.689998] entry_SYSCALL_64_after_hwframe+0x63/0xcd
[ 318.690318] RIP: 0033:0x7fd9e133c48a
[ 318.690687] Code: 48 8b 0d 11 fa 2a 00 f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 49 89 ca b8 a5 00 00 008
[ 318.691357] RSP: 002b:00007ffd374406c8 EFLAGS: 00000202 ORIG_RAX: 00000000000000a5
[ 318.691632] RAX: ffffffffffffffda RBX: 0000564d0b051080 RCX: 00007fd9e133c48a
[ 318.691920] RDX: 0000564d0b051280 RSI: 0000564d0b051300 RDI: 0000564d0b0596a0
[ 318.692123] RBP: 0000000000000000 R08: 0000564d0b0512a0 R09: 0000000000000020
[ 318.692349] R10: 00000000c0ed0000 R11: 0000000000000202 R12: 0000564d0b0596a0
[ 318.692673] R13: 0000564d0b051280 R14: 0000000000000000 R15: 00000000ffffffff
[ 318.693007] </TASK>
[ 318.693271] Modules linked in:
[ 318.693614] CR2: 0000000000000158
[ 318.694446] ---[ end trace 0000000000000000 ]---
[ 318.694779] RIP: 0010:ni_find_attr+0x2d/0x1c0
[ 318.694952] Code: 89 ca 4d 89 c7 41 56 41 55 41 54 41 89 cc 55 48 89 fd 53 48 89 d3 48 83 ec 20 65 48 8b 04 25 28 00 00 00 48 89 44 24 180
[ 318.696042] RSP: 0018:ffffa6c8c0297bd8 EFLAGS: 00000246
[ 318.696531] RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000080
[ 318.698114] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
[ 318.699286] RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
[ 318.699795] R10: 0000000000000000 R11: 0000000000000005 R12: 0000000000000080
[ 318.700236] R13: ffff8d5582e68400 R14: 0000000000000100 R15: 0000000000000000
[ 318.700973] FS: 00007fd9e1c81e40(0000) GS:ffff8d55fdc00000(0000) knlGS:0000000000000000
[
---truncated--- |
| In the Linux kernel, the following vulnerability has been resolved:
raw: Fix NULL deref in raw_get_next().
Dae R. Jeong reported a NULL deref in raw_get_next() [0].
It seems that the repro was running these sequences in parallel so
that one thread was iterating on a socket that was being freed in
another netns.
unshare(0x40060200)
r0 = syz_open_procfs(0x0, &(0x7f0000002080)='net/raw\x00')
socket$inet_icmp_raw(0x2, 0x3, 0x1)
pread64(r0, &(0x7f0000000000)=""/10, 0xa, 0x10000000007f)
After commit 0daf07e52709 ("raw: convert raw sockets to RCU"), we
use RCU and hlist_nulls_for_each_entry() to iterate over SOCK_RAW
sockets. However, we should use spinlock for slow paths to avoid
the NULL deref.
Also, SOCK_RAW does not use SLAB_TYPESAFE_BY_RCU, and the slab object
is not reused during iteration in the grace period. In fact, the
lockless readers do not check the nulls marker with get_nulls_value().
So, SOCK_RAW should use hlist instead of hlist_nulls.
Instead of adding an unnecessary barrier by sk_nulls_for_each_rcu(),
let's convert hlist_nulls to hlist and use sk_for_each_rcu() for
fast paths and sk_for_each() and spinlock for /proc/net/raw.
[0]:
general protection fault, probably for non-canonical address 0xdffffc0000000005: 0000 [#1] PREEMPT SMP KASAN
KASAN: null-ptr-deref in range [0x0000000000000028-0x000000000000002f]
CPU: 2 PID: 20952 Comm: syz-executor.0 Not tainted 6.2.0-g048ec869bafd-dirty #7
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.14.0-0-g155821a1990b-prebuilt.qemu.org 04/01/2014
RIP: 0010:read_pnet include/net/net_namespace.h:383 [inline]
RIP: 0010:sock_net include/net/sock.h:649 [inline]
RIP: 0010:raw_get_next net/ipv4/raw.c:974 [inline]
RIP: 0010:raw_get_idx net/ipv4/raw.c:986 [inline]
RIP: 0010:raw_seq_start+0x431/0x800 net/ipv4/raw.c:995
Code: ef e8 33 3d 94 f7 49 8b 6d 00 4c 89 ef e8 b7 65 5f f7 49 89 ed 49 83 c5 98 0f 84 9a 00 00 00 48 83 c5 c8 48 89 e8 48 c1 e8 03 <42> 80 3c 30 00 74 08 48 89 ef e8 00 3d 94 f7 4c 8b 7d 00 48 89 ef
RSP: 0018:ffffc9001154f9b0 EFLAGS: 00010206
RAX: 0000000000000005 RBX: 1ffff1100302c8fd RCX: 0000000000000000
RDX: 0000000000000028 RSI: ffffc9001154f988 RDI: ffffc9000f77a338
RBP: 0000000000000029 R08: ffffffff8a50ffb4 R09: fffffbfff24b6bd9
R10: fffffbfff24b6bd9 R11: 0000000000000000 R12: ffff88801db73b78
R13: fffffffffffffff9 R14: dffffc0000000000 R15: 0000000000000030
FS: 00007f843ae8e700(0000) GS:ffff888063700000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055bb9614b35f CR3: 000000003c672000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
seq_read_iter+0x4c6/0x10f0 fs/seq_file.c:225
seq_read+0x224/0x320 fs/seq_file.c:162
pde_read fs/proc/inode.c:316 [inline]
proc_reg_read+0x23f/0x330 fs/proc/inode.c:328
vfs_read+0x31e/0xd30 fs/read_write.c:468
ksys_pread64 fs/read_write.c:665 [inline]
__do_sys_pread64 fs/read_write.c:675 [inline]
__se_sys_pread64 fs/read_write.c:672 [inline]
__x64_sys_pread64+0x1e9/0x280 fs/read_write.c:672
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x4e/0xa0 arch/x86/entry/common.c:82
entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x478d29
Code: f7 d8 64 89 02 b8 ff ff ff ff c3 66 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f843ae8dbe8 EFLAGS: 00000246 ORIG_RAX: 0000000000000011
RAX: ffffffffffffffda RBX: 0000000000791408 RCX: 0000000000478d29
RDX: 000000000000000a RSI: 0000000020000000 RDI: 0000000000000003
RBP: 00000000f477909a R08: 0000000000000000 R09: 0000000000000000
R10: 000010000000007f R11: 0000000000000246 R12: 0000000000791740
R13: 0000000000791414 R14: 0000000000791408 R15: 00007ffc2eb48a50
</TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010
---truncated--- |
| In the Linux kernel, the following vulnerability has been resolved:
usb: dwc3: qcom: Fix potential memory leak
Function dwc3_qcom_probe() allocates memory for resource structure
which is pointed by parent_res pointer. This memory is not
freed. This leads to memory leak. Use stack memory to prevent
memory leak.
Found by Linux Verification Center (linuxtesting.org) with SVACE. |
| In the Linux kernel, the following vulnerability has been resolved:
x86/resctrl: Clear staged_config[] before and after it is used
As a temporary storage, staged_config[] in rdt_domain should be cleared
before and after it is used. The stale value in staged_config[] could
cause an MSR access error.
Here is a reproducer on a system with 16 usable CLOSIDs for a 15-way L3
Cache (MBA should be disabled if the number of CLOSIDs for MB is less than
16.) :
mount -t resctrl resctrl -o cdp /sys/fs/resctrl
mkdir /sys/fs/resctrl/p{1..7}
umount /sys/fs/resctrl/
mount -t resctrl resctrl /sys/fs/resctrl
mkdir /sys/fs/resctrl/p{1..8}
An error occurs when creating resource group named p8:
unchecked MSR access error: WRMSR to 0xca0 (tried to write 0x00000000000007ff) at rIP: 0xffffffff82249142 (cat_wrmsr+0x32/0x60)
Call Trace:
<IRQ>
__flush_smp_call_function_queue+0x11d/0x170
__sysvec_call_function+0x24/0xd0
sysvec_call_function+0x89/0xc0
</IRQ>
<TASK>
asm_sysvec_call_function+0x16/0x20
When creating a new resource control group, hardware will be configured
by the following process:
rdtgroup_mkdir()
rdtgroup_mkdir_ctrl_mon()
rdtgroup_init_alloc()
resctrl_arch_update_domains()
resctrl_arch_update_domains() iterates and updates all resctrl_conf_type
whose have_new_ctrl is true. Since staged_config[] holds the same values as
when CDP was enabled, it will continue to update the CDP_CODE and CDP_DATA
configurations. When group p8 is created, get_config_index() called in
resctrl_arch_update_domains() will return 16 and 17 as the CLOSIDs for
CDP_CODE and CDP_DATA, which will be translated to an invalid register -
0xca0 in this scenario.
Fix it by clearing staged_config[] before and after it is used.
[reinette: re-order commit tags] |
| Cross-site request forgery vulnerability exists in LogStare Collector. If a user views a crafted page while logged, unintended operations may be performed. |
| LogStare Collector improperly handles the password hash data. An administrative user may obtain the other users' password hashes. |
| Twonky Server 8.5.2 on Linux and Windows is vulnerable to an access control flaw. An unauthenticated attacker can bypass web service API authentication controls to leak a log file and read the administrator's username and encrypted password. |
| OpenPLC ScadaBR through 0.9.1 on Linux and through 1.12.4 on Windows allows stored XSS via system_settings.shtm. |
| In the Linux kernel, the following vulnerability has been resolved:
vfio/type1: prevent underflow of locked_vm via exec()
When a vfio container is preserved across exec, the task does not change,
but it gets a new mm with locked_vm=0, and loses the count from existing
dma mappings. If the user later unmaps a dma mapping, locked_vm underflows
to a large unsigned value, and a subsequent dma map request fails with
ENOMEM in __account_locked_vm.
To avoid underflow, grab and save the mm at the time a dma is mapped.
Use that mm when adjusting locked_vm, rather than re-acquiring the saved
task's mm, which may have changed. If the saved mm is dead, do nothing.
locked_vm is incremented for existing mappings in a subsequent patch. |
| In the Linux kernel, the following vulnerability has been resolved:
scsi: core: Fix possible memory leak if device_add() fails
If device_add() returns error, the name allocated by dev_set_name() needs
be freed. As the comment of device_add() says, put_device() should be used
to decrease the reference count in the error path. So fix this by calling
put_device(), then the name can be freed in kobject_cleanp(). |
| In the Linux kernel, the following vulnerability has been resolved:
media: hi846: fix usage of pm_runtime_get_if_in_use()
pm_runtime_get_if_in_use() does not only return nonzero values when
the device is in use, it can return a negative errno too.
And especially during resuming from system suspend, when runtime pm
is not yet up again, -EAGAIN is being returned, so the subsequent
pm_runtime_put() call results in a refcount underflow.
Fix system-resume by handling -EAGAIN of pm_runtime_get_if_in_use(). |
| In the Linux kernel, the following vulnerability has been resolved:
PCI: hv: Fix a crash in hv_pci_restore_msi_msg() during hibernation
When a Linux VM with an assigned PCI device runs on Hyper-V, if the PCI
device driver is not loaded yet (i.e. MSI-X/MSI is not enabled on the
device yet), doing a VM hibernation triggers a panic in
hv_pci_restore_msi_msg() -> msi_lock_descs(&pdev->dev), because
pdev->dev.msi.data is still NULL.
Avoid the panic by checking if MSI-X/MSI is enabled. |
| In the Linux kernel, the following vulnerability has been resolved:
wifi: ath12k: Avoid NULL pointer access during management transmit cleanup
Currently 'ar' reference is not added in skb_cb.
Though this is generally not used during transmit completion
callbacks, on interface removal the remaining idr cleanup callback
uses the ar pointer from skb_cb from management txmgmt_idr. Hence fill them
during transmit call for proper usage to avoid NULL pointer dereference.
Tested-on: QCN9274 hw2.0 PCI WLAN.WBE.1.0.1-00029-QCAHKSWPL_SILICONZ-1 |
| In the Linux kernel, the following vulnerability has been resolved:
netfilter: ipset: add the missing IP_SET_HASH_WITH_NET0 macro for ip_set_hash_netportnet.c
The missing IP_SET_HASH_WITH_NET0 macro in ip_set_hash_netportnet can
lead to the use of wrong `CIDR_POS(c)` for calculating array offsets,
which can lead to integer underflow. As a result, it leads to slab
out-of-bound access.
This patch adds back the IP_SET_HASH_WITH_NET0 macro to
ip_set_hash_netportnet to address the issue. |
| In the Linux kernel, the following vulnerability has been resolved:
dma-buf/dma-resv: Stop leaking on krealloc() failure
Currently dma_resv_get_fences() will leak the previously
allocated array if the fence iteration got restarted and
the krealloc_array() fails.
Free the old array by hand, and make sure we still clear
the returned *fences so the caller won't end up accessing
freed memory. Some (but not all) of the callers of
dma_resv_get_fences() seem to still trawl through the
array even when dma_resv_get_fences() failed. And let's
zero out *num_fences as well for good measure. |
| In the Linux kernel, the following vulnerability has been resolved:
wifi: ath9k: don't allow to overwrite ENDPOINT0 attributes
A bad USB device is able to construct a service connection response
message with target endpoint being ENDPOINT0 which is reserved for
HTC_CTRL_RSVD_SVC and should not be modified to be used for any other
services.
Reject such service connection responses.
Found by Linux Verification Center (linuxtesting.org) with Syzkaller. |
| In the Linux kernel, the following vulnerability has been resolved:
skbuff: Fix a race between coalescing and releasing SKBs
Commit 1effe8ca4e34 ("skbuff: fix coalescing for page_pool fragment
recycling") allowed coalescing to proceed with non page pool page and page
pool page when @from is cloned, i.e.
to->pp_recycle --> false
from->pp_recycle --> true
skb_cloned(from) --> true
However, it actually requires skb_cloned(@from) to hold true until
coalescing finishes in this situation. If the other cloned SKB is
released while the merging is in process, from_shinfo->nr_frags will be
set to 0 toward the end of the function, causing the increment of frag
page _refcount to be unexpectedly skipped resulting in inconsistent
reference counts. Later when SKB(@to) is released, it frees the page
directly even though the page pool page is still in use, leading to
use-after-free or double-free errors. So it should be prohibited.
The double-free error message below prompted us to investigate:
BUG: Bad page state in process swapper/1 pfn:0e0d1
page:00000000c6548b28 refcount:-1 mapcount:0 mapping:0000000000000000
index:0x2 pfn:0xe0d1
flags: 0xfffffc0000000(node=0|zone=1|lastcpupid=0x1fffff)
raw: 000fffffc0000000 0000000000000000 ffffffff00000101 0000000000000000
raw: 0000000000000002 0000000000000000 ffffffffffffffff 0000000000000000
page dumped because: nonzero _refcount
CPU: 1 PID: 0 Comm: swapper/1 Tainted: G E 6.2.0+
Call Trace:
<IRQ>
dump_stack_lvl+0x32/0x50
bad_page+0x69/0xf0
free_pcp_prepare+0x260/0x2f0
free_unref_page+0x20/0x1c0
skb_release_data+0x10b/0x1a0
napi_consume_skb+0x56/0x150
net_rx_action+0xf0/0x350
? __napi_schedule+0x79/0x90
__do_softirq+0xc8/0x2b1
__irq_exit_rcu+0xb9/0xf0
common_interrupt+0x82/0xa0
</IRQ>
<TASK>
asm_common_interrupt+0x22/0x40
RIP: 0010:default_idle+0xb/0x20 |
| In the Linux kernel, the following vulnerability has been resolved:
btrfs: fix use-after-free of new block group that became unused
If a task creates a new block group and that block group becomes unused
before we finish its creation, at btrfs_create_pending_block_groups(),
then when btrfs_mark_bg_unused() is called against the block group, we
assume that the block group is currently in the list of block groups to
reclaim, and we move it out of the list of new block groups and into the
list of unused block groups. This has two consequences:
1) We move it out of the list of new block groups associated to the
current transaction. So the block group creation is not finished and
if we attempt to delete the bg because it's unused, we will not find
the block group item in the extent tree (or the new block group tree),
its device extent items in the device tree etc, resulting in the
deletion to fail due to the missing items;
2) We don't increment the reference count on the block group when we
move it to the list of unused block groups, because we assumed the
block group was on the list of block groups to reclaim, and in that
case it already has the correct reference count. However the block
group was on the list of new block groups, in which case no extra
reference was taken because it's local to the current task. This
later results in doing an extra reference count decrement when
removing the block group from the unused list, eventually leading the
reference count to 0.
This second case was caught when running generic/297 from fstests, which
produced the following assertion failure and stack trace:
[589.559] assertion failed: refcount_read(&block_group->refs) == 1, in fs/btrfs/block-group.c:4299
[589.559] ------------[ cut here ]------------
[589.559] kernel BUG at fs/btrfs/block-group.c:4299!
[589.560] invalid opcode: 0000 [#1] PREEMPT SMP PTI
[589.560] CPU: 8 PID: 2819134 Comm: umount Tainted: G W 6.4.0-rc6-btrfs-next-134+ #1
[589.560] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.2-0-gea1b7a073390-prebuilt.qemu.org 04/01/2014
[589.560] RIP: 0010:btrfs_free_block_groups+0x449/0x4a0 [btrfs]
[589.561] Code: 68 62 da c0 (...)
[589.561] RSP: 0018:ffffa55a8c3b3d98 EFLAGS: 00010246
[589.561] RAX: 0000000000000058 RBX: ffff8f030d7f2000 RCX: 0000000000000000
[589.562] RDX: 0000000000000000 RSI: ffffffff953f0878 RDI: 00000000ffffffff
[589.562] RBP: ffff8f030d7f2088 R08: 0000000000000000 R09: ffffa55a8c3b3c50
[589.562] R10: 0000000000000001 R11: 0000000000000001 R12: ffff8f05850b4c00
[589.562] R13: ffff8f030d7f2090 R14: ffff8f05850b4cd8 R15: dead000000000100
[589.563] FS: 00007f497fd2e840(0000) GS:ffff8f09dfc00000(0000) knlGS:0000000000000000
[589.563] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[589.563] CR2: 00007f497ff8ec10 CR3: 0000000271472006 CR4: 0000000000370ee0
[589.563] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[589.564] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[589.564] Call Trace:
[589.564] <TASK>
[589.565] ? __die_body+0x1b/0x60
[589.565] ? die+0x39/0x60
[589.565] ? do_trap+0xeb/0x110
[589.565] ? btrfs_free_block_groups+0x449/0x4a0 [btrfs]
[589.566] ? do_error_trap+0x6a/0x90
[589.566] ? btrfs_free_block_groups+0x449/0x4a0 [btrfs]
[589.566] ? exc_invalid_op+0x4e/0x70
[589.566] ? btrfs_free_block_groups+0x449/0x4a0 [btrfs]
[589.567] ? asm_exc_invalid_op+0x16/0x20
[589.567] ? btrfs_free_block_groups+0x449/0x4a0 [btrfs]
[589.567] ? btrfs_free_block_groups+0x449/0x4a0 [btrfs]
[589.567] close_ctree+0x35d/0x560 [btrfs]
[589.568] ? fsnotify_sb_delete+0x13e/0x1d0
[589.568] ? dispose_list+0x3a/0x50
[589.568] ? evict_inodes+0x151/0x1a0
[589.568] generic_shutdown_super+0x73/0x1a0
[589.569] kill_anon_super+0x14/0x30
[589.569] btrfs_kill_super+0x12/0x20 [btrfs]
[589.569] deactivate_locked
---truncated--- |
| In the Linux kernel, the following vulnerability has been resolved:
net: openvswitch: fix race on port output
assume the following setup on a single machine:
1. An openvswitch instance with one bridge and default flows
2. two network namespaces "server" and "client"
3. two ovs interfaces "server" and "client" on the bridge
4. for each ovs interface a veth pair with a matching name and 32 rx and
tx queues
5. move the ends of the veth pairs to the respective network namespaces
6. assign ip addresses to each of the veth ends in the namespaces (needs
to be the same subnet)
7. start some http server on the server network namespace
8. test if a client in the client namespace can reach the http server
when following the actions below the host has a chance of getting a cpu
stuck in a infinite loop:
1. send a large amount of parallel requests to the http server (around
3000 curls should work)
2. in parallel delete the network namespace (do not delete interfaces or
stop the server, just kill the namespace)
there is a low chance that this will cause the below kernel cpu stuck
message. If this does not happen just retry.
Below there is also the output of bpftrace for the functions mentioned
in the output.
The series of events happening here is:
1. the network namespace is deleted calling
`unregister_netdevice_many_notify` somewhere in the process
2. this sets first `NETREG_UNREGISTERING` on both ends of the veth and
then runs `synchronize_net`
3. it then calls `call_netdevice_notifiers` with `NETDEV_UNREGISTER`
4. this is then handled by `dp_device_event` which calls
`ovs_netdev_detach_dev` (if a vport is found, which is the case for
the veth interface attached to ovs)
5. this removes the rx_handlers of the device but does not prevent
packages to be sent to the device
6. `dp_device_event` then queues the vport deletion to work in
background as a ovs_lock is needed that we do not hold in the
unregistration path
7. `unregister_netdevice_many_notify` continues to call
`netdev_unregister_kobject` which sets `real_num_tx_queues` to 0
8. port deletion continues (but details are not relevant for this issue)
9. at some future point the background task deletes the vport
If after 7. but before 9. a packet is send to the ovs vport (which is
not deleted at this point in time) which forwards it to the
`dev_queue_xmit` flow even though the device is unregistering.
In `skb_tx_hash` (which is called in the `dev_queue_xmit`) path there is
a while loop (if the packet has a rx_queue recorded) that is infinite if
`dev->real_num_tx_queues` is zero.
To prevent this from happening we update `do_output` to handle devices
without carrier the same as if the device is not found (which would
be the code path after 9. is done).
Additionally we now produce a warning in `skb_tx_hash` if we will hit
the infinite loop.
bpftrace (first word is function name):
__dev_queue_xmit server: real_num_tx_queues: 1, cpu: 2, pid: 28024, tid: 28024, skb_addr: 0xffff9edb6f207000, reg_state: 1
netdev_core_pick_tx server: addr: 0xffff9f0a46d4a000 real_num_tx_queues: 1, cpu: 2, pid: 28024, tid: 28024, skb_addr: 0xffff9edb6f207000, reg_state: 1
dp_device_event server: real_num_tx_queues: 1 cpu 9, pid: 21024, tid: 21024, event 2, reg_state: 1
synchronize_rcu_expedited: cpu 9, pid: 21024, tid: 21024
synchronize_rcu_expedited: cpu 9, pid: 21024, tid: 21024
synchronize_rcu_expedited: cpu 9, pid: 21024, tid: 21024
synchronize_rcu_expedited: cpu 9, pid: 21024, tid: 21024
dp_device_event server: real_num_tx_queues: 1 cpu 9, pid: 21024, tid: 21024, event 6, reg_state: 2
ovs_netdev_detach_dev server: real_num_tx_queues: 1 cpu 9, pid: 21024, tid: 21024, reg_state: 2
netdev_rx_handler_unregister server: real_num_tx_queues: 1, cpu: 9, pid: 21024, tid: 21024, reg_state: 2
synchronize_rcu_expedited: cpu 9, pid: 21024, tid: 21024
netdev_rx_handler_unregister ret server: real_num_tx_queues: 1, cpu: 9, pid: 21024, tid: 21024, reg_state: 2
dp_
---truncated--- |
| In the Linux kernel, the following vulnerability has been resolved:
ipv6/addrconf: fix a potential refcount underflow for idev
Now in addrconf_mod_rs_timer(), reference idev depends on whether
rs_timer is not pending. Then modify rs_timer timeout.
There is a time gap in [1], during which if the pending rs_timer
becomes not pending. It will miss to hold idev, but the rs_timer
is activated. Thus rs_timer callback function addrconf_rs_timer()
will be executed and put idev later without holding idev. A refcount
underflow issue for idev can be caused by this.
if (!timer_pending(&idev->rs_timer))
in6_dev_hold(idev);
<--------------[1]
mod_timer(&idev->rs_timer, jiffies + when);
To fix the issue, hold idev if mod_timer() return 0. |
