| CVE |
Vendors |
Products |
Updated |
CVSS v3.1 |
| In the Linux kernel, the following vulnerability has been resolved:
wifi: brcmsmac: add gain range check to wlc_phy_iqcal_gainparams_nphy()
In 'wlc_phy_iqcal_gainparams_nphy()', add gain range check to WARN()
instead of possible out-of-bounds 'tbl_iqcal_gainparams_nphy' access.
Compile tested only.
Found by Linux Verification Center (linuxtesting.org) with SVACE. |
| In the Linux kernel, the following vulnerability has been resolved:
netlink: prevent potential spectre v1 gadgets
Most netlink attributes are parsed and validated from
__nla_validate_parse() or validate_nla()
u16 type = nla_type(nla);
if (type == 0 || type > maxtype) {
/* error or continue */
}
@type is then used as an array index and can be used
as a Spectre v1 gadget.
array_index_nospec() can be used to prevent leaking
content of kernel memory to malicious users.
This should take care of vast majority of netlink uses,
but an audit is needed to take care of others where
validation is not yet centralized in core netlink functions. |
| In the Linux kernel, the following vulnerability has been resolved:
bonding: fix missed rcu protection
When removing the rcu_read_lock in bond_ethtool_get_ts_info() as
discussed [1], I didn't notice it could be called via setsockopt,
which doesn't hold rcu lock, as syzbot pointed:
stack backtrace:
CPU: 0 PID: 3599 Comm: syz-executor317 Not tainted 5.18.0-rc5-syzkaller-01392-g01f4685797a5 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106
bond_option_active_slave_get_rcu include/net/bonding.h:353 [inline]
bond_ethtool_get_ts_info+0x32c/0x3a0 drivers/net/bonding/bond_main.c:5595
__ethtool_get_ts_info+0x173/0x240 net/ethtool/common.c:554
ethtool_get_phc_vclocks+0x99/0x110 net/ethtool/common.c:568
sock_timestamping_bind_phc net/core/sock.c:869 [inline]
sock_set_timestamping+0x3a3/0x7e0 net/core/sock.c:916
sock_setsockopt+0x543/0x2ec0 net/core/sock.c:1221
__sys_setsockopt+0x55e/0x6a0 net/socket.c:2223
__do_sys_setsockopt net/socket.c:2238 [inline]
__se_sys_setsockopt net/socket.c:2235 [inline]
__x64_sys_setsockopt+0xba/0x150 net/socket.c:2235
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7f8902c8eb39
Fix it by adding rcu_read_lock and take a ref on the real_dev.
Since dev_hold() and dev_put() can take NULL these days, we can
skip checking if real_dev exist.
[1] https://lore.kernel.org/netdev/27565.1642742439@famine/ |
| In the Linux kernel, the following vulnerability has been resolved:
media: tc358743: register v4l2 async device only after successful setup
Ensure the device has been setup correctly before registering the v4l2
async device, thus allowing userspace to access. |
| In the Linux kernel, the following vulnerability has been resolved:
mtd: rawnand: denali: Use managed device resources
All of the resources used by this driver has managed interfaces, so use
them. Otherwise we will get the following splat:
[ 4.472703] denali-nand-pci 0000:00:05.0: timeout while waiting for irq 0x1000
[ 4.474071] denali-nand-pci: probe of 0000:00:05.0 failed with error -5
[ 4.473538] nand: No NAND device found
[ 4.474068] BUG: unable to handle page fault for address: ffffc90005000410
[ 4.475169] #PF: supervisor write access in kernel mode
[ 4.475579] #PF: error_code(0x0002) - not-present page
[ 4.478362] RIP: 0010:iowrite32+0x9/0x50
[ 4.486068] Call Trace:
[ 4.486269] <IRQ>
[ 4.486443] denali_isr+0x15b/0x300 [denali]
[ 4.486788] ? denali_direct_write+0x50/0x50 [denali]
[ 4.487189] __handle_irq_event_percpu+0x161/0x3b0
[ 4.487571] handle_irq_event+0x7d/0x1b0
[ 4.487884] handle_fasteoi_irq+0x2b0/0x770
[ 4.488219] __common_interrupt+0xc8/0x1b0
[ 4.488549] common_interrupt+0x9a/0xc0 |
| In the Linux kernel, the following vulnerability has been resolved:
btrfs: release correct delalloc amount in direct IO write path
Running generic/406 causes the following WARNING in btrfs_destroy_inode()
which tells there are outstanding extents left.
In btrfs_get_blocks_direct_write(), we reserve a temporary outstanding
extents with btrfs_delalloc_reserve_metadata() (or indirectly from
btrfs_delalloc_reserve_space(()). We then release the outstanding extents
with btrfs_delalloc_release_extents(). However, the "len" can be modified
in the COW case, which releases fewer outstanding extents than expected.
Fix it by calling btrfs_delalloc_release_extents() for the original length.
To reproduce the warning, the filesystem should be 1 GiB. It's
triggering a short-write, due to not being able to allocate a large
extent and instead allocating a smaller one.
WARNING: CPU: 0 PID: 757 at fs/btrfs/inode.c:8848 btrfs_destroy_inode+0x1e6/0x210 [btrfs]
Modules linked in: btrfs blake2b_generic xor lzo_compress
lzo_decompress raid6_pq zstd zstd_decompress zstd_compress xxhash zram
zsmalloc
CPU: 0 PID: 757 Comm: umount Not tainted 5.17.0-rc8+ #101
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS d55cb5a 04/01/2014
RIP: 0010:btrfs_destroy_inode+0x1e6/0x210 [btrfs]
RSP: 0018:ffffc9000327bda8 EFLAGS: 00010206
RAX: 0000000000000000 RBX: ffff888100548b78 RCX: 0000000000000000
RDX: 0000000000026900 RSI: 0000000000000000 RDI: ffff888100548b78
RBP: ffff888100548940 R08: 0000000000000000 R09: ffff88810b48aba8
R10: 0000000000000001 R11: ffff8881004eb240 R12: ffff88810b48a800
R13: ffff88810b48ec08 R14: ffff88810b48ed00 R15: ffff888100490c68
FS: 00007f8549ea0b80(0000) GS:ffff888237c00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f854a09e733 CR3: 000000010a2e9003 CR4: 0000000000370eb0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
destroy_inode+0x33/0x70
dispose_list+0x43/0x60
evict_inodes+0x161/0x1b0
generic_shutdown_super+0x2d/0x110
kill_anon_super+0xf/0x20
btrfs_kill_super+0xd/0x20 [btrfs]
deactivate_locked_super+0x27/0x90
cleanup_mnt+0x12c/0x180
task_work_run+0x54/0x80
exit_to_user_mode_prepare+0x152/0x160
syscall_exit_to_user_mode+0x12/0x30
do_syscall_64+0x42/0x80
entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7f854a000fb7 |
| In the Linux kernel, the following vulnerability has been resolved:
f2fs: fix to do sanity check on inline_dots inode
As Wenqing reported in bugzilla:
https://bugzilla.kernel.org/show_bug.cgi?id=215765
It will cause a kernel panic with steps:
- mkdir mnt
- mount tmp40.img mnt
- ls mnt
folio_mark_dirty+0x33/0x50
f2fs_add_regular_entry+0x541/0xad0 [f2fs]
f2fs_add_dentry+0x6c/0xb0 [f2fs]
f2fs_do_add_link+0x182/0x230 [f2fs]
__recover_dot_dentries+0x2d6/0x470 [f2fs]
f2fs_lookup+0x5af/0x6a0 [f2fs]
__lookup_slow+0xac/0x200
lookup_slow+0x45/0x70
walk_component+0x16c/0x250
path_lookupat+0x8b/0x1f0
filename_lookup+0xef/0x250
user_path_at_empty+0x46/0x70
vfs_statx+0x98/0x190
__do_sys_newlstat+0x41/0x90
__x64_sys_newlstat+0x1a/0x30
do_syscall_64+0x37/0xb0
entry_SYSCALL_64_after_hwframe+0x44/0xae
The root cause is for special file: e.g. character, block, fifo or
socket file, f2fs doesn't assign address space operations pointer array
for mapping->a_ops field, so, in a fuzzed image, if inline_dots flag was
tagged in special file, during lookup(), when f2fs runs into
__recover_dot_dentries(), it will cause NULL pointer access once
f2fs_add_regular_entry() calls a_ops->set_dirty_page(). |
| In the Linux kernel, the following vulnerability has been resolved:
scsi: hisi_sas: Free irq vectors in order for v3 HW
If the driver probe fails to request the channel IRQ or fatal IRQ, the
driver will free the IRQ vectors before freeing the IRQs in free_irq(),
and this will cause a kernel BUG like this:
------------[ cut here ]------------
kernel BUG at drivers/pci/msi.c:369!
Internal error: Oops - BUG: 0 [#1] PREEMPT SMP
Call trace:
free_msi_irqs+0x118/0x13c
pci_disable_msi+0xfc/0x120
pci_free_irq_vectors+0x24/0x3c
hisi_sas_v3_probe+0x360/0x9d0 [hisi_sas_v3_hw]
local_pci_probe+0x44/0xb0
work_for_cpu_fn+0x20/0x34
process_one_work+0x1d0/0x340
worker_thread+0x2e0/0x460
kthread+0x180/0x190
ret_from_fork+0x10/0x20
---[ end trace b88990335b610c11 ]---
So we use devm_add_action() to control the order in which we free the
vectors. |
| In the Linux kernel, the following vulnerability has been resolved:
geneve: do not assume mac header is set in geneve_xmit_skb()
We should not assume mac header is set in output path.
Use skb_eth_hdr() instead of eth_hdr() to fix the issue.
sysbot reported the following :
WARNING: CPU: 0 PID: 11635 at include/linux/skbuff.h:3052 skb_mac_header include/linux/skbuff.h:3052 [inline]
WARNING: CPU: 0 PID: 11635 at include/linux/skbuff.h:3052 eth_hdr include/linux/if_ether.h:24 [inline]
WARNING: CPU: 0 PID: 11635 at include/linux/skbuff.h:3052 geneve_xmit_skb drivers/net/geneve.c:898 [inline]
WARNING: CPU: 0 PID: 11635 at include/linux/skbuff.h:3052 geneve_xmit+0x4c38/0x5730 drivers/net/geneve.c:1039
Modules linked in:
CPU: 0 UID: 0 PID: 11635 Comm: syz.4.1423 Not tainted 6.12.0-syzkaller-10296-gaaf20f870da0 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
RIP: 0010:skb_mac_header include/linux/skbuff.h:3052 [inline]
RIP: 0010:eth_hdr include/linux/if_ether.h:24 [inline]
RIP: 0010:geneve_xmit_skb drivers/net/geneve.c:898 [inline]
RIP: 0010:geneve_xmit+0x4c38/0x5730 drivers/net/geneve.c:1039
Code: 21 c6 02 e9 35 d4 ff ff e8 a5 48 4c fb 90 0f 0b 90 e9 fd f5 ff ff e8 97 48 4c fb 90 0f 0b 90 e9 d8 f5 ff ff e8 89 48 4c fb 90 <0f> 0b 90 e9 41 e4 ff ff e8 7b 48 4c fb 90 0f 0b 90 e9 cd e7 ff ff
RSP: 0018:ffffc90003b2f870 EFLAGS: 00010283
RAX: 000000000000037a RBX: 000000000000ffff RCX: ffffc9000dc3d000
RDX: 0000000000080000 RSI: ffffffff86428417 RDI: 0000000000000003
RBP: ffffc90003b2f9f0 R08: 0000000000000003 R09: 000000000000ffff
R10: 000000000000ffff R11: 0000000000000002 R12: ffff88806603c000
R13: 0000000000000000 R14: ffff8880685b2780 R15: 0000000000000e23
FS: 00007fdc2deed6c0(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b30a1dff8 CR3: 0000000056b8c000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
__netdev_start_xmit include/linux/netdevice.h:5002 [inline]
netdev_start_xmit include/linux/netdevice.h:5011 [inline]
__dev_direct_xmit+0x58a/0x720 net/core/dev.c:4490
dev_direct_xmit include/linux/netdevice.h:3181 [inline]
packet_xmit+0x1e4/0x360 net/packet/af_packet.c:285
packet_snd net/packet/af_packet.c:3146 [inline]
packet_sendmsg+0x2700/0x5660 net/packet/af_packet.c:3178
sock_sendmsg_nosec net/socket.c:711 [inline]
__sock_sendmsg net/socket.c:726 [inline]
__sys_sendto+0x488/0x4f0 net/socket.c:2197
__do_sys_sendto net/socket.c:2204 [inline]
__se_sys_sendto net/socket.c:2200 [inline]
__x64_sys_sendto+0xe0/0x1c0 net/socket.c:2200
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f |
| In the Linux kernel, the following vulnerability has been resolved:
f2fs: Require FMODE_WRITE for atomic write ioctls
The F2FS ioctls for starting and committing atomic writes check for
inode_owner_or_capable(), but this does not give LSMs like SELinux or
Landlock an opportunity to deny the write access - if the caller's FSUID
matches the inode's UID, inode_owner_or_capable() immediately returns true.
There are scenarios where LSMs want to deny a process the ability to write
particular files, even files that the FSUID of the process owns; but this
can currently partially be bypassed using atomic write ioctls in two ways:
- F2FS_IOC_START_ATOMIC_REPLACE + F2FS_IOC_COMMIT_ATOMIC_WRITE can
truncate an inode to size 0
- F2FS_IOC_START_ATOMIC_WRITE + F2FS_IOC_ABORT_ATOMIC_WRITE can revert
changes another process concurrently made to a file
Fix it by requiring FMODE_WRITE for these operations, just like for
F2FS_IOC_MOVE_RANGE. Since any legitimate caller should only be using these
ioctls when intending to write into the file, that seems unlikely to break
anything. |
| In the Linux kernel, the following vulnerability has been resolved:
drm/bridge: adv7511: fix crash on irq during probe
Moved IRQ registration down to end of adv7511_probe().
If an IRQ already is pending during adv7511_probe
(before adv7511_cec_init) then cec_received_msg_ts
could crash using uninitialized data:
Unable to handle kernel read from unreadable memory at virtual address 00000000000003d5
Internal error: Oops: 96000004 [#1] PREEMPT_RT SMP
Call trace:
cec_received_msg_ts+0x48/0x990 [cec]
adv7511_cec_irq_process+0x1cc/0x308 [adv7511]
adv7511_irq_process+0xd8/0x120 [adv7511]
adv7511_irq_handler+0x1c/0x30 [adv7511]
irq_thread_fn+0x30/0xa0
irq_thread+0x14c/0x238
kthread+0x190/0x1a8 |
| In the Linux kernel, the following vulnerability has been resolved:
tcp_bpf: Fix the sk_mem_uncharge logic in tcp_bpf_sendmsg
The current sk memory accounting logic in __SK_REDIRECT is pre-uncharging
tosend bytes, which is either msg->sg.size or a smaller value apply_bytes.
Potential problems with this strategy are as follows:
- If the actual sent bytes are smaller than tosend, we need to charge some
bytes back, as in line 487, which is okay but seems not clean.
- When tosend is set to apply_bytes, as in line 417, and (ret < 0), we may
miss uncharging (msg->sg.size - apply_bytes) bytes.
[...]
415 tosend = msg->sg.size;
416 if (psock->apply_bytes && psock->apply_bytes < tosend)
417 tosend = psock->apply_bytes;
[...]
443 sk_msg_return(sk, msg, tosend);
444 release_sock(sk);
446 origsize = msg->sg.size;
447 ret = tcp_bpf_sendmsg_redir(sk_redir, redir_ingress,
448 msg, tosend, flags);
449 sent = origsize - msg->sg.size;
[...]
454 lock_sock(sk);
455 if (unlikely(ret < 0)) {
456 int free = sk_msg_free_nocharge(sk, msg);
458 if (!cork)
459 *copied -= free;
460 }
[...]
487 if (eval == __SK_REDIRECT)
488 sk_mem_charge(sk, tosend - sent);
[...]
When running the selftest test_txmsg_redir_wait_sndmem with txmsg_apply,
the following warning will be reported:
------------[ cut here ]------------
WARNING: CPU: 6 PID: 57 at net/ipv4/af_inet.c:156 inet_sock_destruct+0x190/0x1a0
Modules linked in:
CPU: 6 UID: 0 PID: 57 Comm: kworker/6:0 Not tainted 6.12.0-rc1.bm.1-amd64+ #43
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-1 04/01/2014
Workqueue: events sk_psock_destroy
RIP: 0010:inet_sock_destruct+0x190/0x1a0
RSP: 0018:ffffad0a8021fe08 EFLAGS: 00010206
RAX: 0000000000000011 RBX: ffff9aab4475b900 RCX: ffff9aab481a0800
RDX: 0000000000000303 RSI: 0000000000000011 RDI: ffff9aab4475b900
RBP: ffff9aab4475b990 R08: 0000000000000000 R09: ffff9aab40050ec0
R10: 0000000000000000 R11: ffff9aae6fdb1d01 R12: ffff9aab49c60400
R13: ffff9aab49c60598 R14: ffff9aab49c60598 R15: dead000000000100
FS: 0000000000000000(0000) GS:ffff9aae6fd80000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffec7e47bd8 CR3: 00000001a1a1c004 CR4: 0000000000770ef0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
PKRU: 55555554
Call Trace:
<TASK>
? __warn+0x89/0x130
? inet_sock_destruct+0x190/0x1a0
? report_bug+0xfc/0x1e0
? handle_bug+0x5c/0xa0
? exc_invalid_op+0x17/0x70
? asm_exc_invalid_op+0x1a/0x20
? inet_sock_destruct+0x190/0x1a0
__sk_destruct+0x25/0x220
sk_psock_destroy+0x2b2/0x310
process_scheduled_works+0xa3/0x3e0
worker_thread+0x117/0x240
? __pfx_worker_thread+0x10/0x10
kthread+0xcf/0x100
? __pfx_kthread+0x10/0x10
ret_from_fork+0x31/0x40
? __pfx_kthread+0x10/0x10
ret_from_fork_asm+0x1a/0x30
</TASK>
---[ end trace 0000000000000000 ]---
In __SK_REDIRECT, a more concise way is delaying the uncharging after sent
bytes are finalized, and uncharge this value. When (ret < 0), we shall
invoke sk_msg_free.
Same thing happens in case __SK_DROP, when tosend is set to apply_bytes,
we may miss uncharging (msg->sg.size - apply_bytes) bytes. The same
warning will be reported in selftest.
[...]
468 case __SK_DROP:
469 default:
470 sk_msg_free_partial(sk, msg, tosend);
471 sk_msg_apply_bytes(psock, tosend);
472 *copied -= (tosend + delta);
473 return -EACCES;
[...]
So instead of sk_msg_free_partial we can do sk_msg_free here. |
| In the Linux kernel, the following vulnerability has been resolved:
powerpc/iommu: Add missing of_node_put in iommu_init_early_dart
The device_node pointer is returned by of_find_compatible_node
with refcount incremented. We should use of_node_put() to avoid
the refcount leak. |
| In the Linux kernel, the following vulnerability has been resolved:
media: intel/ipu6: do not handle interrupts when device is disabled
Some IPU6 devices have shared interrupts. We need to handle properly
case when interrupt is triggered from other device on shared irq line
and IPU6 itself disabled. In such case we get 0xffffffff from
ISR_STATUS register and handle all irq's cases, for what we are not
not prepared and usually hang the whole system.
To avoid the issue use pm_runtime_get_if_active() to check if
the device is enabled and prevent suspending it when we handle irq
until the end of irq. Additionally use synchronize_irq() in suspend |
| In the Linux kernel, the following vulnerability has been resolved:
thermal: core: call put_device() only after device_register() fails
put_device() shouldn't be called before a prior call to
device_register(). __thermal_cooling_device_register() doesn't follow
that properly and needs fixing. Also
thermal_cooling_device_destroy_sysfs() is getting called unnecessarily
on few error paths.
Fix all this by placing the calls at the right place.
Based on initial work done by Caleb Connolly. |
| In the Linux kernel, the following vulnerability has been resolved:
netfilter: ipset: Fix overflow before widen in the bitmap_ip_create() function.
When first_ip is 0, last_ip is 0xFFFFFFFF, and netmask is 31, the value of
an arithmetic expression 2 << (netmask - mask_bits - 1) is subject
to overflow due to a failure casting operands to a larger data type
before performing the arithmetic.
Note that it's harmless since the value will be checked at the next step.
Found by InfoTeCS on behalf of Linux Verification Center
(linuxtesting.org) with SVACE. |
| In the Linux kernel, the following vulnerability has been resolved:
nilfs2: prevent kernel bug at submit_bh_wbc()
Fix a bug where nilfs_get_block() returns a successful status when
searching and inserting the specified block both fail inconsistently. If
this inconsistent behavior is not due to a previously fixed bug, then an
unexpected race is occurring, so return a temporary error -EAGAIN instead.
This prevents callers such as __block_write_begin_int() from requesting a
read into a buffer that is not mapped, which would cause the BUG_ON check
for the BH_Mapped flag in submit_bh_wbc() to fail. |
| In the Linux kernel, the following vulnerability has been resolved:
rtla: Avoid record NULL pointer dereference
Fix the following null/deref_null.cocci errors:
./tools/tracing/rtla/src/osnoise_hist.c:870:31-36: ERROR: record is NULL but dereferenced.
./tools/tracing/rtla/src/osnoise_top.c:650:31-36: ERROR: record is NULL but dereferenced.
./tools/tracing/rtla/src/timerlat_hist.c:905:31-36: ERROR: record is NULL but dereferenced.
./tools/tracing/rtla/src/timerlat_top.c:700:31-36: ERROR: record is NULL but dereferenced.
"record" is NULL before calling osnoise_init_trace_tool.
Add a tag "out_free" to avoid dereferring a NULL pointer. |
| In the Linux kernel, the following vulnerability has been resolved:
riscv: process: Fix kernel gp leakage
childregs represents the registers which are active for the new thread
in user context. For a kernel thread, childregs->gp is never used since
the kernel gp is not touched by switch_to. For a user mode helper, the
gp value can be observed in user space after execve or possibly by other
means.
[From the email thread]
The /* Kernel thread */ comment is somewhat inaccurate in that it is also used
for user_mode_helper threads, which exec a user process, e.g. /sbin/init or
when /proc/sys/kernel/core_pattern is a pipe. Such threads do not have
PF_KTHREAD set and are valid targets for ptrace etc. even before they exec.
childregs is the *user* context during syscall execution and it is observable
from userspace in at least five ways:
1. kernel_execve does not currently clear integer registers, so the starting
register state for PID 1 and other user processes started by the kernel has
sp = user stack, gp = kernel __global_pointer$, all other integer registers
zeroed by the memset in the patch comment.
This is a bug in its own right, but I'm unwilling to bet that it is the only
way to exploit the issue addressed by this patch.
2. ptrace(PTRACE_GETREGSET): you can PTRACE_ATTACH to a user_mode_helper thread
before it execs, but ptrace requires SIGSTOP to be delivered which can only
happen at user/kernel boundaries.
3. /proc/*/task/*/syscall: this is perfectly happy to read pt_regs for
user_mode_helpers before the exec completes, but gp is not one of the
registers it returns.
4. PERF_SAMPLE_REGS_USER: LOCKDOWN_PERF normally prevents access to kernel
addresses via PERF_SAMPLE_REGS_INTR, but due to this bug kernel addresses
are also exposed via PERF_SAMPLE_REGS_USER which is permitted under
LOCKDOWN_PERF. I have not attempted to write exploit code.
5. Much of the tracing infrastructure allows access to user registers. I have
not attempted to determine which forms of tracing allow access to user
registers without already allowing access to kernel registers. |
| In the Linux kernel, the following vulnerability has been resolved:
netlink: fix false positive warning in extack during dumps
Commit under fixes extended extack reporting to dumps.
It works under normal conditions, because extack errors are
usually reported during ->start() or the first ->dump(),
it's quite rare that the dump starts okay but fails later.
If the dump does fail later, however, the input skb will
already have the initiating message pulled, so checking
if bad attr falls within skb->data will fail.
Switch the check to using nlh, which is always valid.
syzbot found a way to hit that scenario by filling up
the receive queue. In this case we initiate a dump
but don't call ->dump() until there is read space for
an skb.
WARNING: CPU: 1 PID: 5845 at net/netlink/af_netlink.c:2210 netlink_ack_tlv_fill+0x1a8/0x560 net/netlink/af_netlink.c:2209
RIP: 0010:netlink_ack_tlv_fill+0x1a8/0x560 net/netlink/af_netlink.c:2209
Call Trace:
<TASK>
netlink_dump_done+0x513/0x970 net/netlink/af_netlink.c:2250
netlink_dump+0x91f/0xe10 net/netlink/af_netlink.c:2351
netlink_recvmsg+0x6bb/0x11d0 net/netlink/af_netlink.c:1983
sock_recvmsg_nosec net/socket.c:1051 [inline]
sock_recvmsg+0x22f/0x280 net/socket.c:1073
__sys_recvfrom+0x246/0x3d0 net/socket.c:2267
__do_sys_recvfrom net/socket.c:2285 [inline]
__se_sys_recvfrom net/socket.c:2281 [inline]
__x64_sys_recvfrom+0xde/0x100 net/socket.c:2281
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7ff37dd17a79 |