In the Linux kernel, the following vulnerability has been resolved:
perf: Fix __perf_event_overflow() vs perf_remove_from_context() race
Make sure that __perf_event_overflow() runs with IRQs disabled for all
possible callchains. Specifically the software events can end up running
it with only preemption disabled.
This opens up a race vs perf_event_exit_event() and friends that will go
and free various things the overflow path expects to be present, like
the BPF program.
In the Linux kernel, the following vulnerability has been resolved:
f2fs: fix to do sanity check on node footer in {read,write}_end_io
-----------[ cut here ]------------
kernel BUG at fs/f2fs/data.c:358!
Call Trace:
<IRQ>
blk_update_request+0x5eb/0xe70 block/blk-mq.c:987
blk_mq_end_request+0x3e/0x70 block/blk-mq.c:1149
blk_complete_reqs block/blk-mq.c:1224 [inline]
blk_done_softirq+0x107/0x160 block/blk-mq.c:1229
handle_softirqs+0x283/0x870 kernel/softirq.c:579
__do_softirq kernel/softirq.c:613 [inline]
invoke_softirq kernel/softirq.c:453 [inline]
__irq_exit_rcu+0xca/0x1f0 kernel/softirq.c:680
irq_exit_rcu+0x9/0x30 kernel/softirq.c:696
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline]
sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1050
</IRQ>
In f2fs_write_end_io(), it detects there is inconsistency in between
node page index (nid) and footer.nid of node page.
If footer of node page is corrupted in fuzzed image, then we load corrupted
node page w/ async method, e.g. f2fs_ra_node_pages() or f2fs_ra_node_page(),
in where we won't do sanity check on node footer, once node page becomes
dirty, we will encounter this bug after node page writeback.
In the Linux kernel, the following vulnerability has been resolved:
fbdev: rivafb: fix divide error in nv3_arb()
A userspace program can trigger the RIVA NV3 arbitration code by calling
the FBIOPUT_VSCREENINFO ioctl on /dev/fb*. When doing so, the driver
recomputes FIFO arbitration parameters in nv3_arb(), using state->mclk_khz
(derived from the PRAMDAC MCLK PLL) as a divisor without validating it
first.
In a normal setup, state->mclk_khz is provided by the real hardware and is
non-zero. However, an attacker can construct a malicious or misconfigured
device (e.g. a crafted/emulated PCI device) that exposes a bogus PLL
configuration, causing state->mclk_khz to become zero. Once
nv3_get_param() calls nv3_arb(), the division by state->mclk_khz in the gns
calculation causes a divide error and crashes the kernel.
Fix this by checking whether state->mclk_khz is zero and bailing out before
doing the division.
The following log reveals it:
rivafb: setting virtual Y resolution to 2184
divide error: 0000 [#1] PREEMPT SMP KASAN PTI
CPU: 0 PID: 2187 Comm: syz-executor.0 Not tainted 5.18.0-rc1+ #1
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.12.0-59-gc9ba5276e321-prebuilt.qemu.org 04/01/2014
RIP: 0010:nv3_arb drivers/video/fbdev/riva/riva_hw.c:439 [inline]
RIP: 0010:nv3_get_param+0x3ab/0x13b0 drivers/video/fbdev/riva/riva_hw.c:546
Call Trace:
nv3CalcArbitration.constprop.0+0x255/0x460 drivers/video/fbdev/riva/riva_hw.c:603
nv3UpdateArbitrationSettings drivers/video/fbdev/riva/riva_hw.c:637 [inline]
CalcStateExt+0x447/0x1b90 drivers/video/fbdev/riva/riva_hw.c:1246
riva_load_video_mode+0x8a9/0xea0 drivers/video/fbdev/riva/fbdev.c:779
rivafb_set_par+0xc0/0x5f0 drivers/video/fbdev/riva/fbdev.c:1196
fb_set_var+0x604/0xeb0 drivers/video/fbdev/core/fbmem.c:1033
do_fb_ioctl+0x234/0x670 drivers/video/fbdev/core/fbmem.c:1109
fb_ioctl+0xdd/0x130 drivers/video/fbdev/core/fbmem.c:1188
__x64_sys_ioctl+0x122/0x190 fs/ioctl.c:856
In the Linux kernel, the following vulnerability has been resolved:
apparmor: validate DFA start states are in bounds in unpack_pdb
Start states are read from untrusted data and used as indexes into the
DFA state tables. The aa_dfa_next() function call in unpack_pdb() will
access dfa->tables[YYTD_ID_BASE][start], and if the start state exceeds
the number of states in the DFA, this results in an out-of-bound read.
==================================================================
BUG: KASAN: slab-out-of-bounds in aa_dfa_next+0x2a1/0x360
Read of size 4 at addr ffff88811956fb90 by task su/1097
...
Reject policies with out-of-bounds start states during unpacking
to prevent the issue.
In the Linux kernel, the following vulnerability has been resolved:
media: dvb-core: fix wrong reinitialization of ringbuffer on reopen
dvb_dvr_open() calls dvb_ringbuffer_init() when a new reader opens the
DVR device. dvb_ringbuffer_init() calls init_waitqueue_head(), which
reinitializes the waitqueue list head to empty.
Since dmxdev->dvr_buffer.queue is a shared waitqueue (all opens of the
same DVR device share it), this orphans any existing waitqueue entries
from io_uring poll or epoll, leaving them with stale prev/next pointers
while the list head is reset to {self, self}.
The waitqueue and spinlock in dvr_buffer are already properly
initialized once in dvb_dmxdev_init(). The open path only needs to
reset the buffer data pointer, size, and read/write positions.
Replace the dvb_ringbuffer_init() call in dvb_dvr_open() with direct
assignment of data/size and a call to dvb_ringbuffer_reset(), which
properly resets pread, pwrite, and error with correct memory ordering
without touching the waitqueue or spinlock.
In the Linux kernel, the following vulnerability has been resolved:
net: add proper RCU protection to /proc/net/ptype
Yin Fengwei reported an RCU stall in ptype_seq_show() and provided
a patch.
Real issue is that ptype_seq_next() and ptype_seq_show() violate
RCU rules.
ptype_seq_show() runs under rcu_read_lock(), and reads pt->dev
to get device name without any barrier.
At the same time, concurrent writers can remove a packet_type structure
(which is correctly freed after an RCU grace period) and clear pt->dev
without an RCU grace period.
Define ptype_iter_state to carry a dev pointer along seq_net_private:
struct ptype_iter_state {
struct seq_net_private p;
struct net_device *dev; // added in this patch
};
We need to record the device pointer in ptype_get_idx() and
ptype_seq_next() so that ptype_seq_show() is safe against
concurrent pt->dev changes.
We also need to add full RCU protection in ptype_seq_next().
(Missing READ_ONCE() when reading list.next values)
Many thanks to Dong Chenchen for providing a repro.
In the Linux kernel, the following vulnerability has been resolved:
net: liquidio: Fix off-by-one error in PF setup_nic_devices() cleanup
In setup_nic_devices(), the initialization loop jumps to the label
setup_nic_dev_free on failure. The current cleanup loop while(i--)
skip the failing index i, causing a memory leak.
Fix this by changing the loop to iterate from the current index i
down to 0.
Also, decrement i in the devlink_alloc failure path to point to the
last successfully allocated index.
Compile tested only. Issue found using code review.
In the Linux kernel, the following vulnerability has been resolved:
RDMA/umad: Reject negative data_len in ib_umad_write
ib_umad_write computes data_len from user-controlled count and the
MAD header sizes. With a mismatched user MAD header size and RMPP
header length, data_len can become negative and reach ib_create_send_mad().
This can make the padding calculation exceed the segment size and trigger
an out-of-bounds memset in alloc_send_rmpp_list().
Add an explicit check to reject negative data_len before creating the
send buffer.
KASAN splat:
[ 211.363464] BUG: KASAN: slab-out-of-bounds in ib_create_send_mad+0xa01/0x11b0
[ 211.364077] Write of size 220 at addr ffff88800c3fa1f8 by task spray_thread/102
[ 211.365867] ib_create_send_mad+0xa01/0x11b0
[ 211.365887] ib_umad_write+0x853/0x1c80
In the Linux kernel, the following vulnerability has been resolved:
fbdev: smscufx: properly copy ioctl memory to kernelspace
The UFX_IOCTL_REPORT_DAMAGE ioctl does not properly copy data from
userspace to kernelspace, and instead directly references the memory,
which can cause problems if invalid data is passed from userspace. Fix
this all up by correctly copying the memory before accessing it within
the kernel.
In the Linux kernel, the following vulnerability has been resolved:
platform/x86: classmate-laptop: Add missing NULL pointer checks
In a few places in the Classmate laptop driver, code using the accel
object may run before that object's address is stored in the driver
data of the input device using it.
For example, cmpc_accel_sensitivity_store_v4() is the "show" method
of cmpc_accel_sensitivity_attr_v4 which is added in cmpc_accel_add_v4(),
before calling dev_set_drvdata() for inputdev->dev. If the sysfs
attribute is accessed prematurely, the dev_get_drvdata(&inputdev->dev)
call in in cmpc_accel_sensitivity_store_v4() returns NULL which
leads to a NULL pointer dereference going forward.
Moreover, sysfs attributes using the input device are added before
initializing that device by cmpc_add_acpi_notify_device() and if one
of them is accessed before running that function, a NULL pointer
dereference will occur.
For example, cmpc_accel_sensitivity_attr_v4 is added before calling
cmpc_add_acpi_notify_device() and if it is read prematurely, the
dev_get_drvdata(&acpi->dev) call in cmpc_accel_sensitivity_show_v4()
returns NULL which leads to a NULL pointer dereference going forward.
Fix this by adding NULL pointer checks in all of the relevant places.