In the Linux kernel, the following vulnerability has been resolved:
jfs: Fix uninit-value access of imap allocated in the diMount() function
syzbot reports that hex_dump_to_buffer is using uninit-value:
=====================================================
BUG: KMSAN: uninit-value in hex_dump_to_buffer+0x888/0x1100 lib/hexdump.c:171
hex_dump_to_buffer+0x888/0x1100 lib/hexdump.c:171
print_hex_dump+0x13d/0x3e0 lib/hexdump.c:276
diFree+0x5ba/0x4350 fs/jfs/jfs_imap.c:876
jfs_evict_inode+0x510/0x550 fs/jfs/inode.c:156
evict+0x723/0xd10 fs/inode.c:796
iput_final fs/inode.c:1946 [inline]
iput+0x97b/0xdb0 fs/inode.c:1972
txUpdateMap+0xf3e/0x1150 fs/jfs/jfs_txnmgr.c:2367
txLazyCommit fs/jfs/jfs_txnmgr.c:2664 [inline]
jfs_lazycommit+0x627/0x11d0 fs/jfs/jfs_txnmgr.c:2733
kthread+0x6b9/0xef0 kernel/kthread.c:464
ret_from_fork+0x6d/0x90 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Uninit was created at:
slab_post_alloc_hook mm/slub.c:4121 [inline]
slab_alloc_node mm/slub.c:4164 [inline]
__kmalloc_cache_noprof+0x8e3/0xdf0 mm/slub.c:4320
kmalloc_noprof include/linux/slab.h:901 [inline]
diMount+0x61/0x7f0 fs/jfs/jfs_imap.c:105
jfs_mount+0xa8e/0x11d0 fs/jfs/jfs_mount.c:176
jfs_fill_super+0xa47/0x17c0 fs/jfs/super.c:523
get_tree_bdev_flags+0x6ec/0x910 fs/super.c:1636
get_tree_bdev+0x37/0x50 fs/super.c:1659
jfs_get_tree+0x34/0x40 fs/jfs/super.c:635
vfs_get_tree+0xb1/0x5a0 fs/super.c:1814
do_new_mount+0x71f/0x15e0 fs/namespace.c:3560
path_mount+0x742/0x1f10 fs/namespace.c:3887
do_mount fs/namespace.c:3900 [inline]
__do_sys_mount fs/namespace.c:4111 [inline]
__se_sys_mount+0x71f/0x800 fs/namespace.c:4088
__x64_sys_mount+0xe4/0x150 fs/namespace.c:4088
x64_sys_call+0x39bf/0x3c30 arch/x86/include/generated/asm/syscalls_64.h:166
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xcd/0x1e0 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f
=====================================================
The reason is that imap is not properly initialized after memory
allocation. It will cause the snprintf() function to write uninitialized
data into linebuf within hex_dump_to_buffer().
Fix this by using kzalloc instead of kmalloc to clear its content at the
beginning in diMount().
In the Linux kernel, the following vulnerability has been resolved:
net: stmmac: Fix accessing freed irq affinity_hint
In stmmac_request_irq_multi_msi(), a pointer to the stack variable
cpu_mask is passed to irq_set_affinity_hint(). This value is stored in
irq_desc->affinity_hint, but once stmmac_request_irq_multi_msi()
returns, the pointer becomes dangling.
The affinity_hint is exposed via procfs with S_IRUGO permissions,
allowing any unprivileged process to read it. Accessing this stale
pointer can lead to:
- a kernel oops or panic if the referenced memory has been released and
unmapped, or
- leakage of kernel data into userspace if the memory is re-used for
other purposes.
All platforms that use stmmac with PCI MSI (Intel, Loongson, etc) are
affected.
In the Linux kernel, the following vulnerability has been resolved:
media: venus: hfi_parser: refactor hfi packet parsing logic
words_count denotes the number of words in total payload, while data
points to payload of various property within it. When words_count
reaches last word, data can access memory beyond the total payload. This
can lead to OOB access. With this patch, the utility api for handling
individual properties now returns the size of data consumed. Accordingly
remaining bytes are calculated before parsing the payload, thereby
eliminates the OOB access possibilities.
In the Linux kernel, the following vulnerability has been resolved:
media: venus: hfi_parser: add check to avoid out of bound access
There is a possibility that init_codecs is invoked multiple times during
manipulated payload from video firmware. In such case, if codecs_count
can get incremented to value more than MAX_CODEC_NUM, there can be OOB
access. Reset the count so that it always starts from beginning.
In the Linux kernel, the following vulnerability has been resolved:
media: venus: hfi: add check to handle incorrect queue size
qsize represents size of shared queued between driver and video
firmware. Firmware can modify this value to an invalid large value. In
such situation, empty_space will be bigger than the space actually
available. Since new_wr_idx is not checked, so the following code will
result in an OOB write.
...
qsize = qhdr->q_size
if (wr_idx >= rd_idx)
empty_space = qsize - (wr_idx - rd_idx)
....
if (new_wr_idx < qsize) {
memcpy(wr_ptr, packet, dwords << 2) --> OOB write
Add check to ensure qsize is within the allocated size while
reading and writing packets into the queue.
In the Linux kernel, the following vulnerability has been resolved:
media: venus: hfi: add a check to handle OOB in sfr region
sfr->buf_size is in shared memory and can be modified by malicious user.
OOB write is possible when the size is made higher than actual sfr data
buffer. Cap the size to allocated size for such cases.
In the Linux kernel, the following vulnerability has been resolved:
sctp: detect and prevent references to a freed transport in sendmsg
sctp_sendmsg() re-uses associations and transports when possible by
doing a lookup based on the socket endpoint and the message destination
address, and then sctp_sendmsg_to_asoc() sets the selected transport in
all the message chunks to be sent.
There's a possible race condition if another thread triggers the removal
of that selected transport, for instance, by explicitly unbinding an
address with setsockopt(SCTP_SOCKOPT_BINDX_REM), after the chunks have
been set up and before the message is sent. This can happen if the send
buffer is full, during the period when the sender thread temporarily
releases the socket lock in sctp_wait_for_sndbuf().
This causes the access to the transport data in
sctp_outq_select_transport(), when the association outqueue is flushed,
to result in a use-after-free read.
This change avoids this scenario by having sctp_transport_free() signal
the freeing of the transport, tagging it as "dead". In order to do this,
the patch restores the "dead" bit in struct sctp_transport, which was
removed in
commit 47faa1e4c50e ("sctp: remove the dead field of sctp_transport").
Then, in the scenario where the sender thread has released the socket
lock in sctp_wait_for_sndbuf(), the bit is checked again after
re-acquiring the socket lock to detect the deletion. This is done while
holding a reference to the transport to prevent it from being freed in
the process.
If the transport was deleted while the socket lock was relinquished,
sctp_sendmsg_to_asoc() will return -EAGAIN to let userspace retry the
send.
The bug was found by a private syzbot instance (see the error report [1]
and the C reproducer that triggers it [2]).
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:
backlight: led_bl: Hold led_access lock when calling led_sysfs_disable()
Lockdep detects the following issue on led-backlight removal:
[ 142.315935] ------------[ cut here ]------------
[ 142.315954] WARNING: CPU: 2 PID: 292 at drivers/leds/led-core.c:455 led_sysfs_enable+0x54/0x80
...
[ 142.500725] Call trace:
[ 142.503176] led_sysfs_enable+0x54/0x80 (P)
[ 142.507370] led_bl_remove+0x80/0xa8 [led_bl]
[ 142.511742] platform_remove+0x30/0x58
[ 142.515501] device_remove+0x54/0x90
...
Indeed, led_sysfs_enable() has to be called with the led_access
lock held.
Hold the lock when calling led_sysfs_disable().
In the Linux kernel, the following vulnerability has been resolved:
mptcp: fix NULL pointer in can_accept_new_subflow
When testing valkey benchmark tool with MPTCP, the kernel panics in
'mptcp_can_accept_new_subflow' because subflow_req->msk is NULL.
Call trace:
mptcp_can_accept_new_subflow (./net/mptcp/subflow.c:63 (discriminator 4)) (P)
subflow_syn_recv_sock (./net/mptcp/subflow.c:854)
tcp_check_req (./net/ipv4/tcp_minisocks.c:863)
tcp_v4_rcv (./net/ipv4/tcp_ipv4.c:2268)
ip_protocol_deliver_rcu (./net/ipv4/ip_input.c:207)
ip_local_deliver_finish (./net/ipv4/ip_input.c:234)
ip_local_deliver (./net/ipv4/ip_input.c:254)
ip_rcv_finish (./net/ipv4/ip_input.c:449)
...
According to the debug log, the same req received two SYN-ACK in a very
short time, very likely because the client retransmits the syn ack due
to multiple reasons.
Even if the packets are transmitted with a relevant time interval, they
can be processed by the server on different CPUs concurrently). The
'subflow_req->msk' ownership is transferred to the subflow the first,
and there will be a risk of a null pointer dereference here.
This patch fixes this issue by moving the 'subflow_req->msk' under the
`own_req == true` conditional.
Note that the !msk check in subflow_hmac_valid() can be dropped, because
the same check already exists under the own_req mpj branch where the
code has been moved to.