In the Linux kernel, the following vulnerability has been resolved:
mptcp: pm: avoid possible UaF when selecting endp
select_local_address() and select_signal_address() both select an
endpoint entry from the list inside an RCU protected section, but return
a reference to it, to be read later on. If the entry is dereferenced
after the RCU unlock, reading info could cause a Use-after-Free.
A simple solution is to copy the required info while inside the RCU
protected section to avoid any risk of UaF later. The address ID might
need to be modified later to handle the ID0 case later, so a copy seems
OK to deal with.
net: dsa: bcm_sf2: Fix a possible memory leak in bcm_sf2_mdio_register()
In the Linux kernel, the following vulnerability has been resolved:
net: dsa: bcm_sf2: Fix a possible memory leak in bcm_sf2_mdio_register()
bcm_sf2_mdio_register() calls of_phy_find_device() and then
phy_device_remove() in a loop to remove existing PHY devices.
of_phy_find_device() eventually calls bus_find_device(), which calls
get_device() on the returned struct device * to increment the refcount.
The current implementation does not decrement the refcount, which causes
memory leak.
This commit adds the missing phy_device_free() call to decrement the
refcount via put_device() to balance the refcount.
In the Linux kernel, the following vulnerability has been resolved:
s390/sclp: Prevent release of buffer in I/O
When a task waiting for completion of a Store Data operation is
interrupted, an attempt is made to halt this operation. If this attempt
fails due to a hardware or firmware problem, there is a chance that the
SCLP facility might store data into buffers referenced by the original
operation at a later time.
Handle this situation by not releasing the referenced data buffers if
the halt attempt fails. For current use cases, this might result in a
leak of few pages of memory in case of a rare hardware/firmware
malfunction.
binfmt_flat: Fix corruption when not offsetting data start
In the Linux kernel, the following vulnerability has been resolved:
binfmt_flat: Fix corruption when not offsetting data start
Commit 04d82a6d0881 ("binfmt_flat: allow not offsetting data start")
introduced a RISC-V specific variant of the FLAT format which does
not allocate any space for the (obsolete) array of shared library
pointers. However, it did not disable the code which initializes the
array, resulting in the corruption of sizeof(long) bytes before the DATA
segment, generally the end of the TEXT segment.
Introduce MAX_SHARED_LIBS_UPDATE which depends on the state of
CONFIG_BINFMT_FLAT_NO_DATA_START_OFFSET to guard the initializati
In the Linux kernel, the following vulnerability has been resolved:
x86/mm: Fix pti_clone_pgtable() alignment assumption
Guenter reported dodgy crashes on an i386-nosmp build using GCC-11
that had the form of endless traps until entry stack exhaust and then
#DF from the stack guard.
It turned out that pti_clone_pgtable() had alignment assumptions on
the start address, notably it hard assumes start is PMD aligned. This
is true on x86_64, but very much not true on i386.
These assumptions can cause the end condition to malfunction, leading
to a 'short' clone. Guess what happens when the user mapping has a
short copy of the entry text?
Use t
In the Linux kernel, the following vulnerability has been resolved:
usb: gadget: core: Check for unset descriptor
Make sure the descriptor has been set before looking at maxpacket.
This fixes a null pointer panic in this case.
This may happen if the gadget doesn't properly set up the endpoint
for the current speed, or the gadget descriptors are malformed and
the descriptor for the speed/endpoint are not found.
No current gadget driver is known to have this problem, but this
may cause a hard-to-find bug during development of new gadgets.
In the Linux kernel, the following vulnerability has been resolved:
sched/smt: Fix unbalance sched_smt_present dec/inc
I got the following warn report while doing stress test:
jump label: negative count!
WARNING: CPU: 3 PID: 38 at kernel/jump_label.c:263 static_key_slow_try_dec+0x9d/0xb0
Call Trace:
<TASK>
__static_key_slow_dec_cpuslocked+0x16/0x70
sched_cpu_deactivate+0x26e/0x2a0
cpuhp_invoke_callback+0x3ad/0x10d0
cpuhp_thread_fun+0x3f5/0x680
smpboot_thread_fn+0x56d/0x8d0
kthread+0x309/0x400
ret_from_fork+0x41/0x70
ret_from_fork_asm+0x1b/0x30
</TASK>
Because when cpuset_cpu_inactive() fails in sched_cpu_deactivate(),
the cpu of
In the Linux kernel, the following vulnerability has been resolved:
ALSA: line6: Fix racy access to midibuf
There can be concurrent accesses to line6 midibuf from both the URB
completion callback and the rawmidi API access. This could be a cause
of KMSAN warning triggered by syzkaller below (so put as reported-by
here).
This patch protects the midibuf call of the former code path with a
spinlock for avoiding the possible races.
x86/mtrr: Check if fixed MTRRs exist before saving them
In the Linux kernel, the following vulnerability has been resolved:
x86/mtrr: Check if fixed MTRRs exist before saving them
MTRRs have an obsolete fixed variant for fine grained caching control
of the 640K-1MB region that uses separate MSRs. This fixed variant has
a separate capability bit in the MTRR capability MSR.
So far all x86 CPUs which support MTRR have this separate bit set, so it
went unnoticed that mtrr_save_state() does not check the capability bit
before accessing the fixed MTRR MSRs.
Though on a CPU that does not support the fixed MTRR capability this
results in a #GP. The #GP itself is harmless because the RDMSR fault is
ha
fuse: Initialize beyond-EOF page contents before setting uptodate
In the Linux kernel, the following vulnerability has been resolved:
fuse: Initialize beyond-EOF page contents before setting uptodate
fuse_notify_store(), unlike fuse_do_readpage(), does not enable page
zeroing (because it can be used to change partial page contents).
So fuse_notify_store() must be more careful to fully initialize page
contents (including parts of the page that are beyond end-of-file)
before marking the page uptodate.
The current code can leave beyond-EOF page contents uninitialized, which
makes these uninitialized page contents visible to userspace via mmap().
This is an information leak, but only affects systems which
In the Linux kernel, the following vulnerability has been resolved:
kcm: Serialise kcm_sendmsg() for the same socket.
syzkaller reported UAF in kcm_release(). [0]
The scenario is
1. Thread A builds a skb with MSG_MORE and sets kcm->seq_skb.
2. Thread A resumes building skb from kcm->seq_skb but is blocked
by sk_stream_wait_memory()
3. Thread B calls sendmsg() concurrently, finishes building kcm->seq_skb
and puts the skb to the write queue
4. Thread A faces an error and finally frees skb that is already in the
write queue
5. kcm_release() does double-free the skb in the write queue
When a thread is building a
netfilter: ctnetlink: use helper function to calculate expect ID
In the Linux kernel, the following vulnerability has been resolved:
netfilter: ctnetlink: use helper function to calculate expect ID
Delete expectation path is missing a call to the nf_expect_get_id()
helper function to calculate the expectation ID, otherwise LSB of the
expectation object address is leaked to userspace.
f2fs: fix to do sanity check on F2FS_INLINE_DATA flag in inode during GC
In the Linux kernel, the following vulnerability has been resolved:
f2fs: fix to do sanity check on F2FS_INLINE_DATA flag in inode during GC
syzbot reports a f2fs bug as below:
------------[ cut here ]------------
kernel BUG at fs/f2fs/inline.c:258!
CPU: 1 PID: 34 Comm: kworker/u8:2 Not tainted 6.9.0-rc6-syzkaller-00012-g9e4bc4bcae01 #0
RIP: 0010:f2fs_write_inline_data+0x781/0x790 fs/f2fs/inline.c:258
Call Trace:
f2fs_write_single_data_page+0xb65/0x1d60 fs/f2fs/data.c:2834
f2fs_write_cache_pages fs/f2fs/data.c:3133 [inline]
__f2fs_write_data_pages fs/f2fs/data.c:3288 [inline]
f2fs_write_data_pages+0x1efe/0x3a90 fs/f2fs/data.c:3315
do_
fou: remove warn in gue_gro_receive on unsupported protocol
In the Linux kernel, the following vulnerability has been resolved:
fou: remove warn in gue_gro_receive on unsupported protocol
Drop the WARN_ON_ONCE inn gue_gro_receive if the encapsulated type is
not known or does not have a GRO handler.
Such a packet is easily constructed. Syzbot generates them and sets
off this warning.
Remove the warning as it is expected and not actionable.
The warning was previously reduced from WARN_ON to WARN_ON_ONCE in
commit 270136613bf7 ("fou: Do WARN_ON_ONCE in gue_gro_receive for bad
proto callbacks").
In the Linux kernel, the following vulnerability has been resolved:
jfs: Fix shift-out-of-bounds in dbDiscardAG
When searching for the next smaller log2 block, BLKSTOL2() returned 0,
causing shift exponent -1 to be negative.
This patch fixes the issue by exiting the loop directly when negative
shift is found.
In the Linux kernel, the following vulnerability has been resolved:
sctp: Fix null-ptr-deref in reuseport_add_sock().
syzbot reported a null-ptr-deref while accessing sk2->sk_reuseport_cb in
reuseport_add_sock(). [0]
The repro first creates a listener with SO_REUSEPORT. Then, it creates
another listener on the same port and concurrently closes the first
listener.
The second listen() calls reuseport_add_sock() with the first listener as
sk2, where sk2->sk_reuseport_cb is not expected to be cleared concurrently,
but the close() does clear it by reuseport_detach_sock().
The problem is SCTP does not properly synchronise reuseport_alloc(),
r
net: bridge: mcast: wait for previous gc cycles when removing port
In the Linux kernel, the following vulnerability has been resolved:
net: bridge: mcast: wait for previous gc cycles when removing port
syzbot hit a use-after-free[1] which is caused because the bridge doesn't
make sure that all previous garbage has been collected when removing a
port. What happens is:
CPU 1 CPU 2
start gc cycle remove port
acquire gc lock first
wait for lock
call br_multicasg_gc() directly
acquire lock now but free port
the port can be freed
while grp timers still
running
Make sure all previous gc cycles have finished by using flus
gpio: prevent potential speculation leaks in gpio_device_get_desc()
In the Linux kernel, the following vulnerability has been resolved:
gpio: prevent potential speculation leaks in gpio_device_get_desc()
Userspace may trigger a speculative read of an address outside the gpio
descriptor array.
Users can do that by calling gpio_ioctl() with an offset out of range.
Offset is copied from user and then used as an array index to get
the gpio descriptor without sanitization in gpio_device_get_desc().
This change ensures that the offset is sanitized by using
array_index_nospec() to mitigate any possibility of speculative
information leaks.
This bug was discovered and resolved using Coverity Static Analysis
Securi
md/raid5: avoid BUG_ON() while continue reshape after reassembling
In the Linux kernel, the following vulnerability has been resolved:
md/raid5: avoid BUG_ON() while continue reshape after reassembling
Currently, mdadm support --revert-reshape to abort the reshape while
reassembling, as the test 07revert-grow. However, following BUG_ON()
can be triggerred by the test:
kernel BUG at drivers/md/raid5.c:6278!
invalid opcode: 0000 [#1] PREEMPT SMP PTI
irq event stamp: 158985
CPU: 6 PID: 891 Comm: md0_reshape Not tainted 6.9.0-03335-g7592a0b0049a #94
RIP: 0010:reshape_request+0x3f1/0xe60
Call Trace:
<TASK>
raid5_sync_request+0x43d/0x550
md_do_sync+0xb7a/0x2110
md_thread+0x294/0x2b0
kthread+0x147/0x1c0
re