| CVE |
Vendors |
Products |
Updated |
CVSS v3.1 |
| In the Linux kernel, the following vulnerability has been resolved:
fbdev: Fix do_register_framebuffer to prevent null-ptr-deref in fb_videomode_to_var
If fb_add_videomode() in do_register_framebuffer() fails to allocate
memory for fb_videomode, it will later lead to a null-ptr dereference in
fb_videomode_to_var(), as the fb_info is registered while not having the
mode in modelist that is expected to be there, i.e. the one that is
described in fb_info->var.
================================================================
general protection fault, probably for non-canonical address 0xdffffc0000000001: 0000 [#1] PREEMPT SMP KASAN NOPTI
KASAN: null-ptr-deref in range [0x0000000000000008-0x000000000000000f]
CPU: 1 PID: 30371 Comm: syz-executor.1 Not tainted 5.10.226-syzkaller #0
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-1 04/01/2014
RIP: 0010:fb_videomode_to_var+0x24/0x610 drivers/video/fbdev/core/modedb.c:901
Call Trace:
display_to_var+0x3a/0x7c0 drivers/video/fbdev/core/fbcon.c:929
fbcon_resize+0x3e2/0x8f0 drivers/video/fbdev/core/fbcon.c:2071
resize_screen drivers/tty/vt/vt.c:1176 [inline]
vc_do_resize+0x53a/0x1170 drivers/tty/vt/vt.c:1263
fbcon_modechanged+0x3ac/0x6e0 drivers/video/fbdev/core/fbcon.c:2720
fbcon_update_vcs+0x43/0x60 drivers/video/fbdev/core/fbcon.c:2776
do_fb_ioctl+0x6d2/0x740 drivers/video/fbdev/core/fbmem.c:1128
fb_ioctl+0xe7/0x150 drivers/video/fbdev/core/fbmem.c:1203
vfs_ioctl fs/ioctl.c:48 [inline]
__do_sys_ioctl fs/ioctl.c:753 [inline]
__se_sys_ioctl fs/ioctl.c:739 [inline]
__x64_sys_ioctl+0x19a/0x210 fs/ioctl.c:739
do_syscall_64+0x33/0x40 arch/x86/entry/common.c:46
entry_SYSCALL_64_after_hwframe+0x67/0xd1
================================================================
Even though fbcon_init() checks beforehand if fb_match_mode() in
var_to_display() fails, it can not prevent the panic because fbcon_init()
does not return error code. Considering this and the comment in the code
about fb_match_mode() returning NULL - "This should not happen" - it is
better to prevent registering the fb_info if its mode was not set
successfully. Also move fb_add_videomode() closer to the beginning of
do_register_framebuffer() to avoid having to do the cleanup on fail.
Found by Linux Verification Center (linuxtesting.org) with Syzkaller. |
| In the Linux kernel, the following vulnerability has been resolved:
fbdev: Fix fb_set_var to prevent null-ptr-deref in fb_videomode_to_var
If fb_add_videomode() in fb_set_var() fails to allocate memory for
fb_videomode, later it may lead to a null-ptr dereference in
fb_videomode_to_var(), as the fb_info is registered while not having the
mode in modelist that is expected to be there, i.e. the one that is
described in fb_info->var.
================================================================
general protection fault, probably for non-canonical address 0xdffffc0000000001: 0000 [#1] PREEMPT SMP KASAN NOPTI
KASAN: null-ptr-deref in range [0x0000000000000008-0x000000000000000f]
CPU: 1 PID: 30371 Comm: syz-executor.1 Not tainted 5.10.226-syzkaller #0
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-1 04/01/2014
RIP: 0010:fb_videomode_to_var+0x24/0x610 drivers/video/fbdev/core/modedb.c:901
Call Trace:
display_to_var+0x3a/0x7c0 drivers/video/fbdev/core/fbcon.c:929
fbcon_resize+0x3e2/0x8f0 drivers/video/fbdev/core/fbcon.c:2071
resize_screen drivers/tty/vt/vt.c:1176 [inline]
vc_do_resize+0x53a/0x1170 drivers/tty/vt/vt.c:1263
fbcon_modechanged+0x3ac/0x6e0 drivers/video/fbdev/core/fbcon.c:2720
fbcon_update_vcs+0x43/0x60 drivers/video/fbdev/core/fbcon.c:2776
do_fb_ioctl+0x6d2/0x740 drivers/video/fbdev/core/fbmem.c:1128
fb_ioctl+0xe7/0x150 drivers/video/fbdev/core/fbmem.c:1203
vfs_ioctl fs/ioctl.c:48 [inline]
__do_sys_ioctl fs/ioctl.c:753 [inline]
__se_sys_ioctl fs/ioctl.c:739 [inline]
__x64_sys_ioctl+0x19a/0x210 fs/ioctl.c:739
do_syscall_64+0x33/0x40 arch/x86/entry/common.c:46
entry_SYSCALL_64_after_hwframe+0x67/0xd1
================================================================
The reason is that fb_info->var is being modified in fb_set_var(), and
then fb_videomode_to_var() is called. If it fails to add the mode to
fb_info->modelist, fb_set_var() returns error, but does not restore the
old value of fb_info->var. Restore fb_info->var on failure the same way
it is done earlier in the function.
Found by Linux Verification Center (linuxtesting.org) with Syzkaller. |
| In the Linux kernel, the following vulnerability has been resolved:
fs/ntfs3: handle hdr_first_de() return value
The hdr_first_de() function returns a pointer to a struct NTFS_DE. This
pointer may be NULL. To handle the NULL error effectively, it is important
to implement an error handler. This will help manage potential errors
consistently.
Additionally, error handling for the return value already exists at other
points where this function is called.
Found by Linux Verification Center (linuxtesting.org) with SVACE. |
| In the Linux kernel, the following vulnerability has been resolved:
x86/iopl: Cure TIF_IO_BITMAP inconsistencies
io_bitmap_exit() is invoked from exit_thread() when a task exists or
when a fork fails. In the latter case the exit_thread() cleans up
resources which were allocated during fork().
io_bitmap_exit() invokes task_update_io_bitmap(), which in turn ends up
in tss_update_io_bitmap(). tss_update_io_bitmap() operates on the
current task. If current has TIF_IO_BITMAP set, but no bitmap installed,
tss_update_io_bitmap() crashes with a NULL pointer dereference.
There are two issues, which lead to that problem:
1) io_bitmap_exit() should not invoke task_update_io_bitmap() when
the task, which is cleaned up, is not the current task. That's a
clear indicator for a cleanup after a failed fork().
2) A task should not have TIF_IO_BITMAP set and neither a bitmap
installed nor IOPL emulation level 3 activated.
This happens when a kernel thread is created in the context of
a user space thread, which has TIF_IO_BITMAP set as the thread
flags are copied and the IO bitmap pointer is cleared.
Other than in the failed fork() case this has no impact because
kernel threads including IO workers never return to user space and
therefore never invoke tss_update_io_bitmap().
Cure this by adding the missing cleanups and checks:
1) Prevent io_bitmap_exit() to invoke task_update_io_bitmap() if
the to be cleaned up task is not the current task.
2) Clear TIF_IO_BITMAP in copy_thread() unconditionally. For user
space forks it is set later, when the IO bitmap is inherited in
io_bitmap_share().
For paranoia sake, add a warning into tss_update_io_bitmap() to catch
the case, when that code is invoked with inconsistent state. |
| XZ Utils provide a general-purpose data-compression library plus command-line tools. In XZ Utils 5.3.3alpha to 5.8.0, the multithreaded .xz decoder in liblzma has a bug where invalid input can at least result in a crash. The effects include heap use after free and writing to an address based on the null pointer plus an offset. Applications and libraries that use the lzma_stream_decoder_mt function are affected. The bug has been fixed in XZ Utils 5.8.1, and the fix has been committed to the v5.4, v5.6, v5.8, and master branches in the xz Git repository. No new release packages will be made from the old stable branches, but a standalone patch is available that applies to all affected releases. |
| In the Linux kernel, the following vulnerability has been resolved:
net: Fix null-ptr-deref by sock_lock_init_class_and_name() and rmmod.
When I ran the repro [0] and waited a few seconds, I observed two
LOCKDEP splats: a warning immediately followed by a null-ptr-deref. [1]
Reproduction Steps:
1) Mount CIFS
2) Add an iptables rule to drop incoming FIN packets for CIFS
3) Unmount CIFS
4) Unload the CIFS module
5) Remove the iptables rule
At step 3), the CIFS module calls sock_release() for the underlying
TCP socket, and it returns quickly. However, the socket remains in
FIN_WAIT_1 because incoming FIN packets are dropped.
At this point, the module's refcnt is 0 while the socket is still
alive, so the following rmmod command succeeds.
# ss -tan
State Recv-Q Send-Q Local Address:Port Peer Address:Port
FIN-WAIT-1 0 477 10.0.2.15:51062 10.0.0.137:445
# lsmod | grep cifs
cifs 1159168 0
This highlights a discrepancy between the lifetime of the CIFS module
and the underlying TCP socket. Even after CIFS calls sock_release()
and it returns, the TCP socket does not die immediately in order to
close the connection gracefully.
While this is generally fine, it causes an issue with LOCKDEP because
CIFS assigns a different lock class to the TCP socket's sk->sk_lock
using sock_lock_init_class_and_name().
Once an incoming packet is processed for the socket or a timer fires,
sk->sk_lock is acquired.
Then, LOCKDEP checks the lock context in check_wait_context(), where
hlock_class() is called to retrieve the lock class. However, since
the module has already been unloaded, hlock_class() logs a warning
and returns NULL, triggering the null-ptr-deref.
If LOCKDEP is enabled, we must ensure that a module calling
sock_lock_init_class_and_name() (CIFS, NFS, etc) cannot be unloaded
while such a socket is still alive to prevent this issue.
Let's hold the module reference in sock_lock_init_class_and_name()
and release it when the socket is freed in sk_prot_free().
Note that sock_lock_init() clears sk->sk_owner for svc_create_socket()
that calls sock_lock_init_class_and_name() for a listening socket,
which clones a socket by sk_clone_lock() without GFP_ZERO.
[0]:
CIFS_SERVER="10.0.0.137"
CIFS_PATH="//${CIFS_SERVER}/Users/Administrator/Desktop/CIFS_TEST"
DEV="enp0s3"
CRED="/root/WindowsCredential.txt"
MNT=$(mktemp -d /tmp/XXXXXX)
mount -t cifs ${CIFS_PATH} ${MNT} -o vers=3.0,credentials=${CRED},cache=none,echo_interval=1
iptables -A INPUT -s ${CIFS_SERVER} -j DROP
for i in $(seq 10);
do
umount ${MNT}
rmmod cifs
sleep 1
done
rm -r ${MNT}
iptables -D INPUT -s ${CIFS_SERVER} -j DROP
[1]:
DEBUG_LOCKS_WARN_ON(1)
WARNING: CPU: 10 PID: 0 at kernel/locking/lockdep.c:234 hlock_class (kernel/locking/lockdep.c:234 kernel/locking/lockdep.c:223)
Modules linked in: cifs_arc4 nls_ucs2_utils cifs_md4 [last unloaded: cifs]
CPU: 10 UID: 0 PID: 0 Comm: swapper/10 Not tainted 6.14.0 #36
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.0-0-gd239552ce722-prebuilt.qemu.org 04/01/2014
RIP: 0010:hlock_class (kernel/locking/lockdep.c:234 kernel/locking/lockdep.c:223)
...
Call Trace:
<IRQ>
__lock_acquire (kernel/locking/lockdep.c:4853 kernel/locking/lockdep.c:5178)
lock_acquire (kernel/locking/lockdep.c:469 kernel/locking/lockdep.c:5853 kernel/locking/lockdep.c:5816)
_raw_spin_lock_nested (kernel/locking/spinlock.c:379)
tcp_v4_rcv (./include/linux/skbuff.h:1678 ./include/net/tcp.h:2547 net/ipv4/tcp_ipv4.c:2350)
...
BUG: kernel NULL pointer dereference, address: 00000000000000c4
PF: supervisor read access in kernel mode
PF: error_code(0x0000) - not-present page
PGD 0
Oops: Oops: 0000 [#1] PREEMPT SMP NOPTI
CPU: 10 UID: 0 PID: 0 Comm: swapper/10 Tainted: G W 6.14.0 #36
Tainted: [W]=WARN
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.0-0-gd239552ce722-prebuilt.qemu.org 04/01/2014
RIP: 0010:__lock_acquire (kernel/
---truncated--- |
| In the Linux kernel, the following vulnerability has been resolved:
tcp: drop secpath at the same time as we currently drop dst
Xiumei reported hitting the WARN in xfrm6_tunnel_net_exit while
running tests that boil down to:
- create a pair of netns
- run a basic TCP test over ipcomp6
- delete the pair of netns
The xfrm_state found on spi_byaddr was not deleted at the time we
delete the netns, because we still have a reference on it. This
lingering reference comes from a secpath (which holds a ref on the
xfrm_state), which is still attached to an skb. This skb is not
leaked, it ends up on sk_receive_queue and then gets defer-free'd by
skb_attempt_defer_free.
The problem happens when we defer freeing an skb (push it on one CPU's
defer_list), and don't flush that list before the netns is deleted. In
that case, we still have a reference on the xfrm_state that we don't
expect at this point.
We already drop the skb's dst in the TCP receive path when it's no
longer needed, so let's also drop the secpath. At this point,
tcp_filter has already called into the LSM hooks that may require the
secpath, so it should not be needed anymore. However, in some of those
places, the MPTCP extension has just been attached to the skb, so we
cannot simply drop all extensions. |
| In the Linux kernel, the following vulnerability has been resolved:
nfp: bpf: Add check for nfp_app_ctrl_msg_alloc()
Add check for the return value of nfp_app_ctrl_msg_alloc() in
nfp_bpf_cmsg_alloc() to prevent null pointer dereference. |
| In the Linux kernel, the following vulnerability has been resolved:
acct: perform last write from workqueue
In [1] it was reported that the acct(2) system call can be used to
trigger NULL deref in cases where it is set to write to a file that
triggers an internal lookup. This can e.g., happen when pointing acc(2)
to /sys/power/resume. At the point the where the write to this file
happens the calling task has already exited and called exit_fs(). A
lookup will thus trigger a NULL-deref when accessing current->fs.
Reorganize the code so that the the final write happens from the
workqueue but with the caller's credentials. This preserves the
(strange) permission model and has almost no regression risk.
This api should stop to exist though. |
| In the Linux kernel, the following vulnerability has been resolved:
smb: client: Add check for next_buffer in receive_encrypted_standard()
Add check for the return value of cifs_buf_get() and cifs_small_buf_get()
in receive_encrypted_standard() to prevent null pointer dereference. |
| In the Linux kernel, the following vulnerability has been resolved:
ptp: Ensure info->enable callback is always set
The ioctl and sysfs handlers unconditionally call the ->enable callback.
Not all drivers implement that callback, leading to NULL dereferences.
Example of affected drivers: ptp_s390.c, ptp_vclock.c and ptp_mock.c.
Instead use a dummy callback if no better was specified by the driver. |
| In the Linux kernel, the following vulnerability has been resolved:
USB: hub: Ignore non-compliant devices with too many configs or interfaces
Robert Morris created a test program which can cause
usb_hub_to_struct_hub() to dereference a NULL or inappropriate
pointer:
Oops: general protection fault, probably for non-canonical address
0xcccccccccccccccc: 0000 [#1] SMP DEBUG_PAGEALLOC PTI
CPU: 7 UID: 0 PID: 117 Comm: kworker/7:1 Not tainted 6.13.0-rc3-00017-gf44d154d6e3d #14
Hardware name: FreeBSD BHYVE/BHYVE, BIOS 14.0 10/17/2021
Workqueue: usb_hub_wq hub_event
RIP: 0010:usb_hub_adjust_deviceremovable+0x78/0x110
...
Call Trace:
<TASK>
? die_addr+0x31/0x80
? exc_general_protection+0x1b4/0x3c0
? asm_exc_general_protection+0x26/0x30
? usb_hub_adjust_deviceremovable+0x78/0x110
hub_probe+0x7c7/0xab0
usb_probe_interface+0x14b/0x350
really_probe+0xd0/0x2d0
? __pfx___device_attach_driver+0x10/0x10
__driver_probe_device+0x6e/0x110
driver_probe_device+0x1a/0x90
__device_attach_driver+0x7e/0xc0
bus_for_each_drv+0x7f/0xd0
__device_attach+0xaa/0x1a0
bus_probe_device+0x8b/0xa0
device_add+0x62e/0x810
usb_set_configuration+0x65d/0x990
usb_generic_driver_probe+0x4b/0x70
usb_probe_device+0x36/0xd0
The cause of this error is that the device has two interfaces, and the
hub driver binds to interface 1 instead of interface 0, which is where
usb_hub_to_struct_hub() looks.
We can prevent the problem from occurring by refusing to accept hub
devices that violate the USB spec by having more than one
configuration or interface. |
| In the Linux kernel, the following vulnerability has been resolved:
wifi: brcmfmac: fix NULL pointer dereference in brcmf_txfinalize()
On removal of the device or unloading of the kernel module a potential NULL
pointer dereference occurs.
The following sequence deletes the interface:
brcmf_detach()
brcmf_remove_interface()
brcmf_del_if()
Inside the brcmf_del_if() function the drvr->if2bss[ifidx] is updated to
BRCMF_BSSIDX_INVALID (-1) if the bsscfgidx matches.
After brcmf_remove_interface() call the brcmf_proto_detach() function is
called providing the following sequence:
brcmf_detach()
brcmf_proto_detach()
brcmf_proto_msgbuf_detach()
brcmf_flowring_detach()
brcmf_msgbuf_delete_flowring()
brcmf_msgbuf_remove_flowring()
brcmf_flowring_delete()
brcmf_get_ifp()
brcmf_txfinalize()
Since brcmf_get_ip() can and actually will return NULL in this case the
call to brcmf_txfinalize() will result in a NULL pointer dereference inside
brcmf_txfinalize() when trying to update ifp->ndev->stats.tx_errors.
This will only happen if a flowring still has an skb.
Although the NULL pointer dereference has only been seen when trying to
update the tx statistic, all other uses of the ifp pointer have been
guarded as well with an early return if ifp is NULL. |
| In the Linux kernel, the following vulnerability has been resolved:
vsock/virtio: discard packets if the transport changes
If the socket has been de-assigned or assigned to another transport,
we must discard any packets received because they are not expected
and would cause issues when we access vsk->transport.
A possible scenario is described by Hyunwoo Kim in the attached link,
where after a first connect() interrupted by a signal, and a second
connect() failed, we can find `vsk->transport` at NULL, leading to a
NULL pointer dereference. |
| In the Linux kernel, the following vulnerability has been resolved:
vsock: prevent null-ptr-deref in vsock_*[has_data|has_space]
Recent reports have shown how we sometimes call vsock_*_has_data()
when a vsock socket has been de-assigned from a transport (see attached
links), but we shouldn't.
Previous commits should have solved the real problems, but we may have
more in the future, so to avoid null-ptr-deref, we can return 0
(no space, no data available) but with a warning.
This way the code should continue to run in a nearly consistent state
and have a warning that allows us to debug future problems. |
| In the Linux kernel, the following vulnerability has been resolved:
sctp: sysctl: cookie_hmac_alg: avoid using current->nsproxy
As mentioned in a previous commit of this series, using the 'net'
structure via 'current' is not recommended for different reasons:
- Inconsistency: getting info from the reader's/writer's netns vs only
from the opener's netns.
- current->nsproxy can be NULL in some cases, resulting in an 'Oops'
(null-ptr-deref), e.g. when the current task is exiting, as spotted by
syzbot [1] using acct(2).
The 'net' structure can be obtained from the table->data using
container_of().
Note that table->data could also be used directly, as this is the only
member needed from the 'net' structure, but that would increase the size
of this fix, to use '*data' everywhere 'net->sctp.sctp_hmac_alg' is
used. |
| In the Linux kernel, the following vulnerability has been resolved:
sctp: sysctl: rto_min/max: avoid using current->nsproxy
As mentioned in a previous commit of this series, using the 'net'
structure via 'current' is not recommended for different reasons:
- Inconsistency: getting info from the reader's/writer's netns vs only
from the opener's netns.
- current->nsproxy can be NULL in some cases, resulting in an 'Oops'
(null-ptr-deref), e.g. when the current task is exiting, as spotted by
syzbot [1] using acct(2).
The 'net' structure can be obtained from the table->data using
container_of().
Note that table->data could also be used directly, as this is the only
member needed from the 'net' structure, but that would increase the size
of this fix, to use '*data' everywhere 'net->sctp.rto_min/max' is used. |
| In the Linux kernel, the following vulnerability has been resolved:
sctp: sysctl: auth_enable: avoid using current->nsproxy
As mentioned in a previous commit of this series, using the 'net'
structure via 'current' is not recommended for different reasons:
- Inconsistency: getting info from the reader's/writer's netns vs only
from the opener's netns.
- current->nsproxy can be NULL in some cases, resulting in an 'Oops'
(null-ptr-deref), e.g. when the current task is exiting, as spotted by
syzbot [1] using acct(2).
The 'net' structure can be obtained from the table->data using
container_of().
Note that table->data could also be used directly, but that would
increase the size of this fix, while 'sctp.ctl_sock' still needs to be
retrieved from 'net' structure. |
| In the Linux kernel, the following vulnerability has been resolved:
ubifs: skip dumping tnc tree when zroot is null
Clearing slab cache will free all znode in memory and make
c->zroot.znode = NULL, then dumping tnc tree will access
c->zroot.znode which cause null pointer dereference. |
| In the Linux kernel, the following vulnerability has been resolved:
ipmi: ipmb: Add check devm_kasprintf() returned value
devm_kasprintf() can return a NULL pointer on failure but this
returned value is not checked. |