| CVE |
Vendors |
Products |
Updated |
CVSS v3.1 |
| In the Linux kernel, the following vulnerability has been resolved:
net, hsr: reject HSR frame if skb can't hold tag
Receiving HSR frame with insufficient space to hold HSR tag in the skb
can result in a crash (kernel BUG):
[ 45.390915] skbuff: skb_under_panic: text:ffffffff86f32cac len:26 put:14 head:ffff888042418000 data:ffff888042417ff4 tail:0xe end:0x180 dev:bridge_slave_1
[ 45.392559] ------------[ cut here ]------------
[ 45.392912] kernel BUG at net/core/skbuff.c:211!
[ 45.393276] Oops: invalid opcode: 0000 [#1] SMP DEBUG_PAGEALLOC KASAN NOPTI
[ 45.393809] CPU: 1 UID: 0 PID: 2496 Comm: reproducer Not tainted 6.15.0 #12 PREEMPT(undef)
[ 45.394433] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014
[ 45.395273] RIP: 0010:skb_panic+0x15b/0x1d0
<snip registers, remove unreliable trace>
[ 45.402911] Call Trace:
[ 45.403105] <IRQ>
[ 45.404470] skb_push+0xcd/0xf0
[ 45.404726] br_dev_queue_push_xmit+0x7c/0x6c0
[ 45.406513] br_forward_finish+0x128/0x260
[ 45.408483] __br_forward+0x42d/0x590
[ 45.409464] maybe_deliver+0x2eb/0x420
[ 45.409763] br_flood+0x174/0x4a0
[ 45.410030] br_handle_frame_finish+0xc7c/0x1bc0
[ 45.411618] br_handle_frame+0xac3/0x1230
[ 45.413674] __netif_receive_skb_core.constprop.0+0x808/0x3df0
[ 45.422966] __netif_receive_skb_one_core+0xb4/0x1f0
[ 45.424478] __netif_receive_skb+0x22/0x170
[ 45.424806] process_backlog+0x242/0x6d0
[ 45.425116] __napi_poll+0xbb/0x630
[ 45.425394] net_rx_action+0x4d1/0xcc0
[ 45.427613] handle_softirqs+0x1a4/0x580
[ 45.427926] do_softirq+0x74/0x90
[ 45.428196] </IRQ>
This issue was found by syzkaller.
The panic happens in br_dev_queue_push_xmit() once it receives a
corrupted skb with ETH header already pushed in linear data. When it
attempts the skb_push() call, there's not enough headroom and
skb_push() panics.
The corrupted skb is put on the queue by HSR layer, which makes a
sequence of unintended transformations when it receives a specific
corrupted HSR frame (with incomplete TAG).
Fix it by dropping and consuming frames that are not long enough to
contain both ethernet and hsr headers.
Alternative fix would be to check for enough headroom before skb_push()
in br_dev_queue_push_xmit().
In the reproducer, this is injected via AF_PACKET, but I don't easily
see why it couldn't be sent over the wire from adjacent network.
Further Details:
In the reproducer, the following network interface chain is set up:
┌────────────────┐ ┌────────────────┐
│ veth0_to_hsr ├───┤ hsr_slave0 ┼───┐
└────────────────┘ └────────────────┘ │
│ ┌──────┐
├─┤ hsr0 ├───┐
│ └──────┘ │
┌────────────────┐ ┌────────────────┐ │ │┌────────┐
│ veth1_to_hsr ┼───┤ hsr_slave1 ├───┘ └┤ │
└────────────────┘ └────────────────┘ ┌┼ bridge │
││ │
│└────────┘
│
┌───────┐ │
│ ... ├──────┘
└───────┘
To trigger the events leading up to crash, reproducer sends a corrupted
HSR fr
---truncated--- |
| In the Linux kernel, the following vulnerability has been resolved:
ipv6: sr: Fix MAC comparison to be constant-time
To prevent timing attacks, MACs need to be compared in constant time.
Use the appropriate helper function for this. |
| In the Linux kernel, the following vulnerability has been resolved:
NFS: Fix a race when updating an existing write
After nfs_lock_and_join_requests() tests for whether the request is
still attached to the mapping, nothing prevents a call to
nfs_inode_remove_request() from succeeding until we actually lock the
page group.
The reason is that whoever called nfs_inode_remove_request() doesn't
necessarily have a lock on the page group head.
So in order to avoid races, let's take the page group lock earlier in
nfs_lock_and_join_requests(), and hold it across the removal of the
request in nfs_inode_remove_request(). |
| In the Linux kernel, the following vulnerability has been resolved:
s390/sclp: Fix SCCB present check
Tracing code called by the SCLP interrupt handler contains early exits
if the SCCB address associated with an interrupt is NULL. This check is
performed after physical to virtual address translation.
If the kernel identity mapping does not start at address zero, the
resulting virtual address is never zero, so that the NULL checks won't
work. Subsequently this may result in incorrect accesses to the first
page of the identity mapping.
Fix this by introducing a function that handles the NULL case before
address translation. |
| In the Linux kernel, the following vulnerability has been resolved:
tracing: Limit access to parser->buffer when trace_get_user failed
When the length of the string written to set_ftrace_filter exceeds
FTRACE_BUFF_MAX, the following KASAN alarm will be triggered:
BUG: KASAN: slab-out-of-bounds in strsep+0x18c/0x1b0
Read of size 1 at addr ffff0000d00bd5ba by task ash/165
CPU: 1 UID: 0 PID: 165 Comm: ash Not tainted 6.16.0-g6bcdbd62bd56-dirty
Hardware name: linux,dummy-virt (DT)
Call trace:
show_stack+0x34/0x50 (C)
dump_stack_lvl+0xa0/0x158
print_address_description.constprop.0+0x88/0x398
print_report+0xb0/0x280
kasan_report+0xa4/0xf0
__asan_report_load1_noabort+0x20/0x30
strsep+0x18c/0x1b0
ftrace_process_regex.isra.0+0x100/0x2d8
ftrace_regex_release+0x484/0x618
__fput+0x364/0xa58
____fput+0x28/0x40
task_work_run+0x154/0x278
do_notify_resume+0x1f0/0x220
el0_svc+0xec/0xf0
el0t_64_sync_handler+0xa0/0xe8
el0t_64_sync+0x1ac/0x1b0
The reason is that trace_get_user will fail when processing a string
longer than FTRACE_BUFF_MAX, but not set the end of parser->buffer to 0.
Then an OOB access will be triggered in ftrace_regex_release->
ftrace_process_regex->strsep->strpbrk. We can solve this problem by
limiting access to parser->buffer when trace_get_user failed. |
| In the Linux kernel, the following vulnerability has been resolved:
tls: fix handling of zero-length records on the rx_list
Each recvmsg() call must process either
- only contiguous DATA records (any number of them)
- one non-DATA record
If the next record has different type than what has already been
processed we break out of the main processing loop. If the record
has already been decrypted (which may be the case for TLS 1.3 where
we don't know type until decryption) we queue the pending record
to the rx_list. Next recvmsg() will pick it up from there.
Queuing the skb to rx_list after zero-copy decrypt is not possible,
since in that case we decrypted directly to the user space buffer,
and we don't have an skb to queue (darg.skb points to the ciphertext
skb for access to metadata like length).
Only data records are allowed zero-copy, and we break the processing
loop after each non-data record. So we should never zero-copy and
then find out that the record type has changed. The corner case
we missed is when the initial record comes from rx_list, and it's
zero length. |
| In the Linux kernel, the following vulnerability has been resolved:
ppp: fix race conditions in ppp_fill_forward_path
ppp_fill_forward_path() has two race conditions:
1. The ppp->channels list can change between list_empty() and
list_first_entry(), as ppp_lock() is not held. If the only channel
is deleted in ppp_disconnect_channel(), list_first_entry() may
access an empty head or a freed entry, and trigger a panic.
2. pch->chan can be NULL. When ppp_unregister_channel() is called,
pch->chan is set to NULL before pch is removed from ppp->channels.
Fix these by using a lockless RCU approach:
- Use list_first_or_null_rcu() to safely test and access the first list
entry.
- Convert list modifications on ppp->channels to their RCU variants and
add synchronize_net() after removal.
- Check for a NULL pch->chan before dereferencing it. |
| In the Linux kernel, the following vulnerability has been resolved:
gve: prevent ethtool ops after shutdown
A crash can occur if an ethtool operation is invoked
after shutdown() is called.
shutdown() is invoked during system shutdown to stop DMA operations
without performing expensive deallocations. It is discouraged to
unregister the netdev in this path, so the device may still be visible
to userspace and kernel helpers.
In gve, shutdown() tears down most internal data structures. If an
ethtool operation is dispatched after shutdown(), it will dereference
freed or NULL pointers, leading to a kernel panic. While graceful
shutdown normally quiesces userspace before invoking the reboot
syscall, forced shutdowns (as observed on GCP VMs) can still trigger
this path.
Fix by calling netif_device_detach() in shutdown().
This marks the device as detached so the ethtool ioctl handler
will skip dispatching operations to the driver. |
| In the Linux kernel, the following vulnerability has been resolved:
smb3: fix for slab out of bounds on mount to ksmbd
With KASAN enabled, it is possible to get a slab out of bounds
during mount to ksmbd due to missing check in parse_server_interfaces()
(see below):
BUG: KASAN: slab-out-of-bounds in
parse_server_interfaces+0x14ee/0x1880 [cifs]
Read of size 4 at addr ffff8881433dba98 by task mount/9827
CPU: 5 UID: 0 PID: 9827 Comm: mount Tainted: G
OE 6.16.0-rc2-kasan #2 PREEMPT(voluntary)
Tainted: [O]=OOT_MODULE, [E]=UNSIGNED_MODULE
Hardware name: Dell Inc. Precision Tower 3620/0MWYPT,
BIOS 2.13.1 06/14/2019
Call Trace:
<TASK>
dump_stack_lvl+0x9f/0xf0
print_report+0xd1/0x670
__virt_addr_valid+0x22c/0x430
? parse_server_interfaces+0x14ee/0x1880 [cifs]
? kasan_complete_mode_report_info+0x2a/0x1f0
? parse_server_interfaces+0x14ee/0x1880 [cifs]
kasan_report+0xd6/0x110
parse_server_interfaces+0x14ee/0x1880 [cifs]
__asan_report_load_n_noabort+0x13/0x20
parse_server_interfaces+0x14ee/0x1880 [cifs]
? __pfx_parse_server_interfaces+0x10/0x10 [cifs]
? trace_hardirqs_on+0x51/0x60
SMB3_request_interfaces+0x1ad/0x3f0 [cifs]
? __pfx_SMB3_request_interfaces+0x10/0x10 [cifs]
? SMB2_tcon+0x23c/0x15d0 [cifs]
smb3_qfs_tcon+0x173/0x2b0 [cifs]
? __pfx_smb3_qfs_tcon+0x10/0x10 [cifs]
? cifs_get_tcon+0x105d/0x2120 [cifs]
? do_raw_spin_unlock+0x5d/0x200
? cifs_get_tcon+0x105d/0x2120 [cifs]
? __pfx_smb3_qfs_tcon+0x10/0x10 [cifs]
cifs_mount_get_tcon+0x369/0xb90 [cifs]
? dfs_cache_find+0xe7/0x150 [cifs]
dfs_mount_share+0x985/0x2970 [cifs]
? check_path.constprop.0+0x28/0x50
? save_trace+0x54/0x370
? __pfx_dfs_mount_share+0x10/0x10 [cifs]
? __lock_acquire+0xb82/0x2ba0
? __kasan_check_write+0x18/0x20
cifs_mount+0xbc/0x9e0 [cifs]
? __pfx_cifs_mount+0x10/0x10 [cifs]
? do_raw_spin_unlock+0x5d/0x200
? cifs_setup_cifs_sb+0x29d/0x810 [cifs]
cifs_smb3_do_mount+0x263/0x1990 [cifs] |
| In the Linux kernel, the following vulnerability has been resolved:
nfsd: handle get_client_locked() failure in nfsd4_setclientid_confirm()
Lei Lu recently reported that nfsd4_setclientid_confirm() did not check
the return value from get_client_locked(). a SETCLIENTID_CONFIRM could
race with a confirmed client expiring and fail to get a reference. That
could later lead to a UAF.
Fix this by getting a reference early in the case where there is an
extant confirmed client. If that fails then treat it as if there were no
confirmed client found at all.
In the case where the unconfirmed client is expiring, just fail and
return the result from get_client_locked(). |
| In the Linux kernel, the following vulnerability has been resolved:
hfs: fix slab-out-of-bounds in hfs_bnode_read()
This patch introduces is_bnode_offset_valid() method that checks
the requested offset value. Also, it introduces
check_and_correct_requested_length() method that checks and
correct the requested length (if it is necessary). These methods
are used in hfs_bnode_read(), hfs_bnode_write(), hfs_bnode_clear(),
hfs_bnode_copy(), and hfs_bnode_move() with the goal to prevent
the access out of allocated memory and triggering the crash. |
| In the Linux kernel, the following vulnerability has been resolved:
hfsplus: fix slab-out-of-bounds in hfsplus_bnode_read()
The hfsplus_bnode_read() method can trigger the issue:
[ 174.852007][ T9784] ==================================================================
[ 174.852709][ T9784] BUG: KASAN: slab-out-of-bounds in hfsplus_bnode_read+0x2f4/0x360
[ 174.853412][ T9784] Read of size 8 at addr ffff88810b5fc6c0 by task repro/9784
[ 174.854059][ T9784]
[ 174.854272][ T9784] CPU: 1 UID: 0 PID: 9784 Comm: repro Not tainted 6.16.0-rc3 #7 PREEMPT(full)
[ 174.854281][ T9784] Hardware name: QEMU Ubuntu 24.04 PC (i440FX + PIIX, 1996), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
[ 174.854286][ T9784] Call Trace:
[ 174.854289][ T9784] <TASK>
[ 174.854292][ T9784] dump_stack_lvl+0x10e/0x1f0
[ 174.854305][ T9784] print_report+0xd0/0x660
[ 174.854315][ T9784] ? __virt_addr_valid+0x81/0x610
[ 174.854323][ T9784] ? __phys_addr+0xe8/0x180
[ 174.854330][ T9784] ? hfsplus_bnode_read+0x2f4/0x360
[ 174.854337][ T9784] kasan_report+0xc6/0x100
[ 174.854346][ T9784] ? hfsplus_bnode_read+0x2f4/0x360
[ 174.854354][ T9784] hfsplus_bnode_read+0x2f4/0x360
[ 174.854362][ T9784] hfsplus_bnode_dump+0x2ec/0x380
[ 174.854370][ T9784] ? __pfx_hfsplus_bnode_dump+0x10/0x10
[ 174.854377][ T9784] ? hfsplus_bnode_write_u16+0x83/0xb0
[ 174.854385][ T9784] ? srcu_gp_start+0xd0/0x310
[ 174.854393][ T9784] ? __mark_inode_dirty+0x29e/0xe40
[ 174.854402][ T9784] hfsplus_brec_remove+0x3d2/0x4e0
[ 174.854411][ T9784] __hfsplus_delete_attr+0x290/0x3a0
[ 174.854419][ T9784] ? __pfx_hfs_find_1st_rec_by_cnid+0x10/0x10
[ 174.854427][ T9784] ? __pfx___hfsplus_delete_attr+0x10/0x10
[ 174.854436][ T9784] ? __asan_memset+0x23/0x50
[ 174.854450][ T9784] hfsplus_delete_all_attrs+0x262/0x320
[ 174.854459][ T9784] ? __pfx_hfsplus_delete_all_attrs+0x10/0x10
[ 174.854469][ T9784] ? rcu_is_watching+0x12/0xc0
[ 174.854476][ T9784] ? __mark_inode_dirty+0x29e/0xe40
[ 174.854483][ T9784] hfsplus_delete_cat+0x845/0xde0
[ 174.854493][ T9784] ? __pfx_hfsplus_delete_cat+0x10/0x10
[ 174.854507][ T9784] hfsplus_unlink+0x1ca/0x7c0
[ 174.854516][ T9784] ? __pfx_hfsplus_unlink+0x10/0x10
[ 174.854525][ T9784] ? down_write+0x148/0x200
[ 174.854532][ T9784] ? __pfx_down_write+0x10/0x10
[ 174.854540][ T9784] vfs_unlink+0x2fe/0x9b0
[ 174.854549][ T9784] do_unlinkat+0x490/0x670
[ 174.854557][ T9784] ? __pfx_do_unlinkat+0x10/0x10
[ 174.854565][ T9784] ? __might_fault+0xbc/0x130
[ 174.854576][ T9784] ? getname_flags.part.0+0x1c5/0x550
[ 174.854584][ T9784] __x64_sys_unlink+0xc5/0x110
[ 174.854592][ T9784] do_syscall_64+0xc9/0x480
[ 174.854600][ T9784] entry_SYSCALL_64_after_hwframe+0x77/0x7f
[ 174.854608][ T9784] RIP: 0033:0x7f6fdf4c3167
[ 174.854614][ T9784] Code: f0 ff ff 73 01 c3 48 8b 0d 26 0d 0e 00 f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 08
[ 174.854622][ T9784] RSP: 002b:00007ffcb948bca8 EFLAGS: 00000206 ORIG_RAX: 0000000000000057
[ 174.854630][ T9784] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f6fdf4c3167
[ 174.854636][ T9784] RDX: 00007ffcb948bcc0 RSI: 00007ffcb948bcc0 RDI: 00007ffcb948bd50
[ 174.854641][ T9784] RBP: 00007ffcb948cd90 R08: 0000000000000001 R09: 00007ffcb948bb40
[ 174.854645][ T9784] R10: 00007f6fdf564fc0 R11: 0000000000000206 R12: 0000561e1bc9c2d0
[ 174.854650][ T9784] R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
[ 174.854658][ T9784] </TASK>
[ 174.854661][ T9784]
[ 174.879281][ T9784] Allocated by task 9784:
[ 174.879664][ T9784] kasan_save_stack+0x20/0x40
[ 174.880082][ T9784] kasan_save_track+0x14/0x30
[ 174.880500][ T9784] __kasan_kmalloc+0xaa/0xb0
[ 174.880908][ T9784] __kmalloc_noprof+0x205/0x550
[ 174.881337][ T9784] __hfs_bnode_create+0x107/0x890
[ 174.881779][ T9784] hfsplus_bnode_find+0x2d0/0xd10
[ 174.882222][ T9784] hfsplus_brec_find+0x2b0/0x520
[ 174.882659][ T9784] hfsplus_delete_all_attrs+0x23b/0x3
---truncated--- |
| In the Linux kernel, the following vulnerability has been resolved:
drbd: add missing kref_get in handle_write_conflicts
With `two-primaries` enabled, DRBD tries to detect "concurrent" writes
and handle write conflicts, so that even if you write to the same sector
simultaneously on both nodes, they end up with the identical data once
the writes are completed.
In handling "superseeded" writes, we forgot a kref_get,
resulting in a premature drbd_destroy_device and use after free,
and further to kernel crashes with symptoms.
Relevance: No one should use DRBD as a random data generator, and apparently
all users of "two-primaries" handle concurrent writes correctly on layer up.
That is cluster file systems use some distributed lock manager,
and live migration in virtualization environments stops writes on one node
before starting writes on the other node.
Which means that other than for "test cases",
this code path is never taken in real life.
FYI, in DRBD 9, things are handled differently nowadays. We still detect
"write conflicts", but no longer try to be smart about them.
We decided to disconnect hard instead: upper layers must not submit concurrent
writes. If they do, that's their fault. |
| In the Linux kernel, the following vulnerability has been resolved:
fs/ntfs3: Add sanity check for file name
The length of the file name should be smaller than the directory entry size. |
| In the Linux kernel, the following vulnerability has been resolved:
comedi: fix race between polling and detaching
syzbot reports a use-after-free in comedi in the below link, which is
due to comedi gladly removing the allocated async area even though poll
requests are still active on the wait_queue_head inside of it. This can
cause a use-after-free when the poll entries are later triggered or
removed, as the memory for the wait_queue_head has been freed. We need
to check there are no tasks queued on any of the subdevices' wait queues
before allowing the device to be detached by the `COMEDI_DEVCONFIG`
ioctl.
Tasks will read-lock `dev->attach_lock` before adding themselves to the
subdevice wait queue, so fix the problem in the `COMEDI_DEVCONFIG` ioctl
handler by write-locking `dev->attach_lock` before checking that all of
the subdevices are safe to be deleted. This includes testing for any
sleepers on the subdevices' wait queues. It remains locked until the
device has been detached. This requires the `comedi_device_detach()`
function to be refactored slightly, moving the bulk of it into new
function `comedi_device_detach_locked()`.
Note that the refactor of `comedi_device_detach()` results in
`comedi_device_cancel_all()` now being called while `dev->attach_lock`
is write-locked, which wasn't the case previously, but that does not
matter.
Thanks to Jens Axboe for diagnosing the problem and co-developing this
patch. |
| In the Linux kernel, the following vulnerability has been resolved:
media: venus: Fix OOB read due to missing payload bound check
Currently, The event_seq_changed() handler processes a variable number
of properties sent by the firmware. The number of properties is indicated
by the firmware and used to iterate over the payload. However, the
payload size is not being validated against the actual message length.
This can lead to out-of-bounds memory access if the firmware provides a
property count that exceeds the data available in the payload. Such a
condition can result in kernel crashes or potential information leaks if
memory beyond the buffer is accessed.
Fix this by properly validating the remaining size of the payload before
each property access and updating bounds accordingly as properties are
parsed.
This ensures that property parsing is safely bounded within the received
message buffer and protects against malformed or malicious firmware
behavior. |
| In the Linux kernel, the following vulnerability has been resolved:
f2fs: fix to avoid out-of-boundary access in dnode page
As Jiaming Zhang reported:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x1c1/0x2a0 lib/dump_stack.c:120
print_address_description mm/kasan/report.c:378 [inline]
print_report+0x17e/0x800 mm/kasan/report.c:480
kasan_report+0x147/0x180 mm/kasan/report.c:593
data_blkaddr fs/f2fs/f2fs.h:3053 [inline]
f2fs_data_blkaddr fs/f2fs/f2fs.h:3058 [inline]
f2fs_get_dnode_of_data+0x1a09/0x1c40 fs/f2fs/node.c:855
f2fs_reserve_block+0x53/0x310 fs/f2fs/data.c:1195
prepare_write_begin fs/f2fs/data.c:3395 [inline]
f2fs_write_begin+0xf39/0x2190 fs/f2fs/data.c:3594
generic_perform_write+0x2c7/0x910 mm/filemap.c:4112
f2fs_buffered_write_iter fs/f2fs/file.c:4988 [inline]
f2fs_file_write_iter+0x1ec8/0x2410 fs/f2fs/file.c:5216
new_sync_write fs/read_write.c:593 [inline]
vfs_write+0x546/0xa90 fs/read_write.c:686
ksys_write+0x149/0x250 fs/read_write.c:738
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xf3/0x3d0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
The root cause is in the corrupted image, there is a dnode has the same
node id w/ its inode, so during f2fs_get_dnode_of_data(), it tries to
access block address in dnode at offset 934, however it parses the dnode
as inode node, so that get_dnode_addr() returns 360, then it tries to
access page address from 360 + 934 * 4 = 4096 w/ 4 bytes.
To fix this issue, let's add sanity check for node id of all direct nodes
during f2fs_get_dnode_of_data(). |
| In the Linux kernel, the following vulnerability has been resolved:
arm64/entry: Mask DAIF in cpu_switch_to(), call_on_irq_stack()
`cpu_switch_to()` and `call_on_irq_stack()` manipulate SP to change
to different stacks along with the Shadow Call Stack if it is enabled.
Those two stack changes cannot be done atomically and both functions
can be interrupted by SErrors or Debug Exceptions which, though unlikely,
is very much broken : if interrupted, we can end up with mismatched stacks
and Shadow Call Stack leading to clobbered stacks.
In `cpu_switch_to()`, it can happen when SP_EL0 points to the new task,
but x18 stills points to the old task's SCS. When the interrupt handler
tries to save the task's SCS pointer, it will save the old task
SCS pointer (x18) into the new task struct (pointed to by SP_EL0),
clobbering it.
In `call_on_irq_stack()`, it can happen when switching from the task stack
to the IRQ stack and when switching back. In both cases, we can be
interrupted when the SCS pointer points to the IRQ SCS, but SP points to
the task stack. The nested interrupt handler pushes its return addresses
on the IRQ SCS. It then detects that SP points to the task stack,
calls `call_on_irq_stack()` and clobbers the task SCS pointer with
the IRQ SCS pointer, which it will also use !
This leads to tasks returning to addresses on the wrong SCS,
or even on the IRQ SCS, triggering kernel panics via CONFIG_VMAP_STACK
or FPAC if enabled.
This is possible on a default config, but unlikely.
However, when enabling CONFIG_ARM64_PSEUDO_NMI, DAIF is unmasked and
instead the GIC is responsible for filtering what interrupts the CPU
should receive based on priority.
Given the goal of emulating NMIs, pseudo-NMIs can be received by the CPU
even in `cpu_switch_to()` and `call_on_irq_stack()`, possibly *very*
frequently depending on the system configuration and workload, leading
to unpredictable kernel panics.
Completely mask DAIF in `cpu_switch_to()` and restore it when returning.
Do the same in `call_on_irq_stack()`, but restore and mask around
the branch.
Mask DAIF even if CONFIG_SHADOW_CALL_STACK is not enabled for consistency
of behaviour between all configurations.
Introduce and use an assembly macro for saving and masking DAIF,
as the existing one saves but only masks IF. |
| In the Linux kernel, the following vulnerability has been resolved:
f2fs: fix to avoid out-of-boundary access in devs.path
- touch /mnt/f2fs/012345678901234567890123456789012345678901234567890123
- truncate -s $((1024*1024*1024)) \
/mnt/f2fs/012345678901234567890123456789012345678901234567890123
- touch /mnt/f2fs/file
- truncate -s $((1024*1024*1024)) /mnt/f2fs/file
- mkfs.f2fs /mnt/f2fs/012345678901234567890123456789012345678901234567890123 \
-c /mnt/f2fs/file
- mount /mnt/f2fs/012345678901234567890123456789012345678901234567890123 \
/mnt/f2fs/loop
[16937.192225] F2FS-fs (loop0): Mount Device [ 0]: /mnt/f2fs/012345678901234567890123456789012345678901234567890123\xff\x01, 511, 0 - 3ffff
[16937.192268] F2FS-fs (loop0): Failed to find devices
If device path length equals to MAX_PATH_LEN, sbi->devs.path[] may
not end up w/ null character due to path array is fully filled, So
accidently, fields locate after path[] may be treated as part of
device path, result in parsing wrong device path.
struct f2fs_dev_info {
...
char path[MAX_PATH_LEN];
...
};
Let's add one byte space for sbi->devs.path[] to store null
character of device path string. |
| In the Linux kernel, the following vulnerability has been resolved:
netfilter: xt_nfacct: don't assume acct name is null-terminated
BUG: KASAN: slab-out-of-bounds in .. lib/vsprintf.c:721
Read of size 1 at addr ffff88801eac95c8 by task syz-executor183/5851
[..]
string+0x231/0x2b0 lib/vsprintf.c:721
vsnprintf+0x739/0xf00 lib/vsprintf.c:2874
[..]
nfacct_mt_checkentry+0xd2/0xe0 net/netfilter/xt_nfacct.c:41
xt_check_match+0x3d1/0xab0 net/netfilter/x_tables.c:523
nfnl_acct_find_get() handles non-null input, but the error
printk relied on its presence. |