In the Linux kernel, the following vulnerability has been resolved:
ASoC: lpass: Fix for KASAN use_after_free out of bounds
When we run syzkaller we get below Out of Bounds error.
"KASAN: slab-out-of-bounds Read in regcache_flat_read"
Below is the backtrace of the issue:
BUG: KASAN: slab-out-of-bounds in regcache_flat_read+0x10c/0x110
Read of size 4 at addr ffffff8088fbf714 by task syz-executor.4/14144
CPU: 6 PID: 14144 Comm: syz-executor.4 Tainted: G W
Hardware name: Qualcomm Technologies, Inc. sc7280 CRD platform (rev5+) (DT)
Call trace:
dump_backtrace+0x0/0x4ec
show_stack+0x34/0x50
dump_stack_lvl+0xdc/0x11c
print_address_description+0x30/0x2d8
kasan_report+0x178/0x1e4
__asan_report_load4_noabort+0x44/0x50
regcache_flat_read+0x10c/0x110
regcache_read+0xf8/0x5a0
_regmap_read+0x45c/0x86c
_regmap_update_bits+0x128/0x290
regmap_update_bits_base+0xc0/0x15c
snd_soc_component_update_bits+0xa8/0x22c
snd_soc_component_write_field+0x68/0xd4
tx_macro_put_dec_enum+0x1d0/0x268
snd_ctl_elem_write+0x288/0x474
By Error checking and checking valid values issue gets rectifies.
In the Linux kernel, the following vulnerability has been resolved:
wifi: ath9k: hif_usb: fix memory leak of remain_skbs
hif_dev->remain_skb is allocated and used exclusively in
ath9k_hif_usb_rx_stream(). It is implied that an allocated remain_skb is
processed and subsequently freed (in error paths) only during the next
call of ath9k_hif_usb_rx_stream().
So, if the urbs are deallocated between those two calls due to the device
deinitialization or suspend, it is possible that ath9k_hif_usb_rx_stream()
is not called next time and the allocated remain_skb is leaked. Our local
Syzkaller instance was able to trigger that.
remain_skb makes sense when receiving two consecutive urbs which are
logically linked together, i.e. a specific data field from the first skb
indicates a cached skb to be allocated, memcpy'd with some data and
subsequently processed in the next call to ath9k_hif_usb_rx_stream(). Urbs
deallocation supposedly makes that link irrelevant so we need to free the
cached skb in those cases.
Fix the leak by introducing a function to explicitly free remain_skb (if
it is not NULL) when the rx urbs have been deallocated. remain_skb is NULL
when it has not been allocated at all (hif_dev struct is kzalloced) or
when it has been processed in next call to ath9k_hif_usb_rx_stream().
Found by Linux Verification Center (linuxtesting.org) with Syzkaller.
In the Linux kernel, the following vulnerability has been resolved:
x86: fix clear_user_rep_good() exception handling annotation
This code no longer exists in mainline, because it was removed in
commit d2c95f9d6802 ("x86: don't use REP_GOOD or ERMS for user memory
clearing") upstream.
However, rather than backport the full range of x86 memory clearing and
copying cleanups, fix the exception table annotation placement for the
final 'rep movsb' in clear_user_rep_good(): rather than pointing at the
actual instruction that did the user space access, it pointed to the
register move just before it.
That made sense from a code flow standpoint, but not from an actual
usage standpoint: it means that if user access takes an exception, the
exception handler won't actually find the instruction in the exception
tables.
As a result, rather than fixing it up and returning -EFAULT, it would
then turn it into a kernel oops report instead, something like:
BUG: unable to handle page fault for address: 0000000020081000
#PF: supervisor write access in kernel mode
#PF: error_code(0x0002) - not-present page
...
RIP: 0010:clear_user_rep_good+0x1c/0x30 arch/x86/lib/clear_page_64.S:147
...
Call Trace:
__clear_user arch/x86/include/asm/uaccess_64.h:103 [inline]
clear_user arch/x86/include/asm/uaccess_64.h:124 [inline]
iov_iter_zero+0x709/0x1290 lib/iov_iter.c:800
iomap_dio_hole_iter fs/iomap/direct-io.c:389 [inline]
iomap_dio_iter fs/iomap/direct-io.c:440 [inline]
__iomap_dio_rw+0xe3d/0x1cd0 fs/iomap/direct-io.c:601
iomap_dio_rw+0x40/0xa0 fs/iomap/direct-io.c:689
ext4_dio_read_iter fs/ext4/file.c:94 [inline]
ext4_file_read_iter+0x4be/0x690 fs/ext4/file.c:145
call_read_iter include/linux/fs.h:2183 [inline]
do_iter_readv_writev+0x2e0/0x3b0 fs/read_write.c:733
do_iter_read+0x2f2/0x750 fs/read_write.c:796
vfs_readv+0xe5/0x150 fs/read_write.c:916
do_preadv+0x1b6/0x270 fs/read_write.c:1008
__do_sys_preadv2 fs/read_write.c:1070 [inline]
__se_sys_preadv2 fs/read_write.c:1061 [inline]
__x64_sys_preadv2+0xef/0x150 fs/read_write.c:1061
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x63/0xcd
which then looks like a filesystem bug rather than the incorrect
exception annotation that it is.
[ The alternative to this one-liner fix is to take the upstream series
that cleans this all up:
68674f94ffc9 ("x86: don't use REP_GOOD or ERMS for small memory copies")
20f3337d350c ("x86: don't use REP_GOOD or ERMS for small memory clearing")
adfcf4231b8c ("x86: don't use REP_GOOD or ERMS for user memory copies")
* d2c95f9d6802 ("x86: don't use REP_GOOD or ERMS for user memory clearing")
3639a535587d ("x86: move stac/clac from user copy routines into callers")
577e6a7fd50d ("x86: inline the 'rep movs' in user copies for the FSRM case")
8c9b6a88b7e2 ("x86: improve on the non-rep 'clear_user' function")
427fda2c8a49 ("x86: improve on the non-rep 'copy_user' function")
* e046fe5a36a9 ("x86: set FSRS automatically on AMD CPUs that have FSRM")
e1f2750edc4a ("x86: remove 'zerorest' argument from __copy_user_nocache()")
034ff37d3407 ("x86: rewrite '__copy_user_nocache' function")
with either the whole series or at a minimum the two marked commits
being needed to fix this issue ]
In the Linux kernel, the following vulnerability has been resolved:
platform/x86: dell-sysman: Fix reference leak
If a duplicate attribute is found using kset_find_obj(),
a reference to that attribute is returned. This means
that we need to dispose it accordingly. Use kobject_put()
to dispose the duplicate attribute in such a case.
Compile-tested only.
In the Linux kernel, the following vulnerability has been resolved:
netfilter: conntrack: fix wrong ct->timeout value
(struct nf_conn)->timeout is an interval before the conntrack
confirmed. After confirmed, it becomes a timestamp.
It is observed that timeout of an unconfirmed conntrack:
- Set by calling ctnetlink_change_timeout(). As a result,
`nfct_time_stamp` was wrongly added to `ct->timeout` twice.
- Get by calling ctnetlink_dump_timeout(). As a result,
`nfct_time_stamp` was wrongly subtracted.
Call Trace:
<TASK>
dump_stack_lvl
ctnetlink_dump_timeout
__ctnetlink_glue_build
ctnetlink_glue_build
__nfqnl_enqueue_packet
nf_queue
nf_hook_slow
ip_mc_output
? __pfx_ip_finish_output
ip_send_skb
? __pfx_dst_output
udp_send_skb
udp_sendmsg
? __pfx_ip_generic_getfrag
sock_sendmsg
Separate the 2 cases in:
- Setting `ct->timeout` in __nf_ct_set_timeout().
- Getting `ct->timeout` in ctnetlink_dump_timeout().
Pablo appends:
Update ctnetlink to set up the timeout _after_ the IPS_CONFIRMED flag is
set on, otherwise conntrack creation via ctnetlink breaks.
Note that the problem described in this patch occurs since the
introduction of the nfnetlink_queue conntrack support, select a
sufficiently old Fixes: tag for -stable kernel to pick up this fix.
In the Linux kernel, the following vulnerability has been resolved:
clk: microchip: fix potential UAF in auxdev release callback
Similar to commit 1c11289b34ab ("peci: cpu: Fix use-after-free in
adev_release()"), the auxiliary device is not torn down in the correct
order. If auxiliary_device_add() fails, the release callback will be
called twice, resulting in a UAF. Due to timing, the auxdev code in this
driver "took inspiration" from the aforementioned commit, and thus its
bugs too!
Moving auxiliary_device_uninit() to the unregister callback instead
avoids the issue.
In the Linux kernel, the following vulnerability has been resolved:
net/sched: sch_fq: fix integer overflow of "credit"
if sch_fq is configured with "initial quantum" having values greater than
INT_MAX, the first assignment of "credit" does signed integer overflow to
a very negative value.
In this situation, the syzkaller script provided by Cristoph triggers the
CPU soft-lockup warning even with few sockets. It's not an infinite loop,
but "credit" wasn't probably meant to be minus 2Gb for each new flow.
Capping "initial quantum" to INT_MAX proved to fix the issue.
v2: validation of "initial quantum" is done in fq_policy, instead of open
coding in fq_change() _ suggested by Jakub Kicinski
In the Linux kernel, the following vulnerability has been resolved:
soc: aspeed: socinfo: Add kfree for kstrdup
Add kfree() in the later error handling in order to avoid memory leak.