Security Vulnerabilities - CVEs Published In August 2024
In the Linux kernel, the following vulnerability has been resolved:
usb: gadget: f_ncm: fix potential NULL ptr deref in ncm_bitrate()
In Google internal bug 265639009 we've received an (as yet) unreproducible
crash report from an aarch64 GKI 5.10.149-android13 running device.
AFAICT the source code is at:
https://android.googlesource.com/kernel/common/+/refs/tags/ASB-2022-12-05_13-5.10
The call stack is:
ncm_close() -> ncm_notify() -> ncm_do_notify()
with the crash at:
ncm_do_notify+0x98/0x270
Code: 79000d0b b9000a6c f940012a f9400269 (b9405d4b)
Which I believe disassembles to (I don't know ARM assembly, but it looks sane enough to me...):
// halfword (16-bit) store presumably to event->wLength (at offset 6 of struct usb_cdc_notification)
0B 0D 00 79 strh w11, [x8, #6]
// word (32-bit) store presumably to req->Length (at offset 8 of struct usb_request)
6C 0A 00 B9 str w12, [x19, #8]
// x10 (NULL) was read here from offset 0 of valid pointer x9
// IMHO we're reading 'cdev->gadget' and getting NULL
// gadget is indeed at offset 0 of struct usb_composite_dev
2A 01 40 F9 ldr x10, [x9]
// loading req->buf pointer, which is at offset 0 of struct usb_request
69 02 40 F9 ldr x9, [x19]
// x10 is null, crash, appears to be attempt to read cdev->gadget->max_speed
4B 5D 40 B9 ldr w11, [x10, #0x5c]
which seems to line up with ncm_do_notify() case NCM_NOTIFY_SPEED code fragment:
event->wLength = cpu_to_le16(8);
req->length = NCM_STATUS_BYTECOUNT;
/* SPEED_CHANGE data is up/down speeds in bits/sec */
data = req->buf + sizeof *event;
data[0] = cpu_to_le32(ncm_bitrate(cdev->gadget));
My analysis of registers and NULL ptr deref crash offset
(Unable to handle kernel NULL pointer dereference at virtual address 000000000000005c)
heavily suggests that the crash is due to 'cdev->gadget' being NULL when executing:
data[0] = cpu_to_le32(ncm_bitrate(cdev->gadget));
which calls:
ncm_bitrate(NULL)
which then calls:
gadget_is_superspeed(NULL)
which reads
((struct usb_gadget *)NULL)->max_speed
and hits a panic.
AFAICT, if I'm counting right, the offset of max_speed is indeed 0x5C.
(remember there's a GKI KABI reservation of 16 bytes in struct work_struct)
It's not at all clear to me how this is all supposed to work...
but returning 0 seems much better than panic-ing...
CVSS Score
5.5
EPSS Score
0.0
Published
2024-08-21
In the Linux kernel, the following vulnerability has been resolved:
dmaengine: idxd: Let probe fail when workqueue cannot be enabled
The workqueue is enabled when the appropriate driver is loaded and
disabled when the driver is removed. When the driver is removed it
assumes that the workqueue was enabled successfully and proceeds to
free allocations made during workqueue enabling.
Failure during workqueue enabling does not prevent the driver from
being loaded. This is because the error path within drv_enable_wq()
returns success unless a second failure is encountered
during the error path. By returning success it is possible to load
the driver even if the workqueue cannot be enabled and
allocations that do not exist are attempted to be freed during
driver remove.
Some examples of problematic flows:
(a)
idxd_dmaengine_drv_probe() -> drv_enable_wq() -> idxd_wq_request_irq():
In above flow, if idxd_wq_request_irq() fails then
idxd_wq_unmap_portal() is called on error exit path, but
drv_enable_wq() returns 0 because idxd_wq_disable() succeeds. The
driver is thus loaded successfully.
idxd_dmaengine_drv_remove()->drv_disable_wq()->idxd_wq_unmap_portal()
Above flow on driver unload triggers the WARN in devm_iounmap() because
the device resource has already been removed during error path of
drv_enable_wq().
(b)
idxd_dmaengine_drv_probe() -> drv_enable_wq() -> idxd_wq_request_irq():
In above flow, if idxd_wq_request_irq() fails then
idxd_wq_init_percpu_ref() is never called to initialize the percpu
counter, yet the driver loads successfully because drv_enable_wq()
returns 0.
idxd_dmaengine_drv_remove()->__idxd_wq_quiesce()->percpu_ref_kill():
Above flow on driver unload triggers a BUG when attempting to drop the
initial ref of the uninitialized percpu ref:
BUG: kernel NULL pointer dereference, address: 0000000000000010
Fix the drv_enable_wq() error path by returning the original error that
indicates failure of workqueue enabling. This ensures that the probe
fails when an error is encountered and the driver remove paths are only
attempted when the workqueue was enabled successfully.
CVSS Score
5.5
EPSS Score
0.0
Published
2024-08-21
In the Linux kernel, the following vulnerability has been resolved:
USB: gadgetfs: Fix race between mounting and unmounting
The syzbot fuzzer and Gerald Lee have identified a use-after-free bug
in the gadgetfs driver, involving processes concurrently mounting and
unmounting the gadgetfs filesystem. In particular, gadgetfs_fill_super()
can race with gadgetfs_kill_sb(), causing the latter to deallocate
the_device while the former is using it. The output from KASAN says,
in part:
BUG: KASAN: use-after-free in instrument_atomic_read_write include/linux/instrumented.h:102 [inline]
BUG: KASAN: use-after-free in atomic_fetch_sub_release include/linux/atomic/atomic-instrumented.h:176 [inline]
BUG: KASAN: use-after-free in __refcount_sub_and_test include/linux/refcount.h:272 [inline]
BUG: KASAN: use-after-free in __refcount_dec_and_test include/linux/refcount.h:315 [inline]
BUG: KASAN: use-after-free in refcount_dec_and_test include/linux/refcount.h:333 [inline]
BUG: KASAN: use-after-free in put_dev drivers/usb/gadget/legacy/inode.c:159 [inline]
BUG: KASAN: use-after-free in gadgetfs_kill_sb+0x33/0x100 drivers/usb/gadget/legacy/inode.c:2086
Write of size 4 at addr ffff8880276d7840 by task syz-executor126/18689
CPU: 0 PID: 18689 Comm: syz-executor126 Not tainted 6.1.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022
Call Trace:
<TASK>
...
atomic_fetch_sub_release include/linux/atomic/atomic-instrumented.h:176 [inline]
__refcount_sub_and_test include/linux/refcount.h:272 [inline]
__refcount_dec_and_test include/linux/refcount.h:315 [inline]
refcount_dec_and_test include/linux/refcount.h:333 [inline]
put_dev drivers/usb/gadget/legacy/inode.c:159 [inline]
gadgetfs_kill_sb+0x33/0x100 drivers/usb/gadget/legacy/inode.c:2086
deactivate_locked_super+0xa7/0xf0 fs/super.c:332
vfs_get_super fs/super.c:1190 [inline]
get_tree_single+0xd0/0x160 fs/super.c:1207
vfs_get_tree+0x88/0x270 fs/super.c:1531
vfs_fsconfig_locked fs/fsopen.c:232 [inline]
The simplest solution is to ensure that gadgetfs_fill_super() and
gadgetfs_kill_sb() are serialized by making them both acquire a new
mutex.
CVSS Score
4.7
EPSS Score
0.0
Published
2024-08-21
In the Linux kernel, the following vulnerability has been resolved:
tty: fix possible null-ptr-defer in spk_ttyio_release
Run the following tests on the qemu platform:
syzkaller:~# modprobe speakup_audptr
input: Speakup as /devices/virtual/input/input4
initialized device: /dev/synth, node (MAJOR 10, MINOR 125)
speakup 3.1.6: initialized
synth name on entry is: (null)
synth probe
spk_ttyio_initialise_ldisc failed because tty_kopen_exclusive returned
failed (errno -16), then remove the module, we will get a null-ptr-defer
problem, as follow:
syzkaller:~# modprobe -r speakup_audptr
releasing synth audptr
BUG: kernel NULL pointer dereference, address: 0000000000000080
#PF: supervisor write access in kernel mode
#PF: error_code(0x0002) - not-present page
PGD 0 P4D 0
Oops: 0002 [#1] PREEMPT SMP PTI
CPU: 2 PID: 204 Comm: modprobe Not tainted 6.1.0-rc6-dirty #1
RIP: 0010:mutex_lock+0x14/0x30
Call Trace:
<TASK>
spk_ttyio_release+0x19/0x70 [speakup]
synth_release.part.6+0xac/0xc0 [speakup]
synth_remove+0x56/0x60 [speakup]
__x64_sys_delete_module+0x156/0x250
? fpregs_assert_state_consistent+0x1d/0x50
do_syscall_64+0x37/0x90
entry_SYSCALL_64_after_hwframe+0x63/0xcd
</TASK>
Modules linked in: speakup_audptr(-) speakup
Dumping ftrace buffer:
in_synth->dev was not initialized during modprobe, so we add check
for in_synth->dev to fix this bug.
CVSS Score
5.5
EPSS Score
0.0
Published
2024-08-21
In the Linux kernel, the following vulnerability has been resolved:
tty: serial: qcom-geni-serial: fix slab-out-of-bounds on RX FIFO buffer
Driver's probe allocates memory for RX FIFO (port->rx_fifo) based on
default RX FIFO depth, e.g. 16. Later during serial startup the
qcom_geni_serial_port_setup() updates the RX FIFO depth
(port->rx_fifo_depth) to match real device capabilities, e.g. to 32.
The RX UART handle code will read "port->rx_fifo_depth" number of words
into "port->rx_fifo" buffer, thus exceeding the bounds. This can be
observed in certain configurations with Qualcomm Bluetooth HCI UART
device and KASAN:
Bluetooth: hci0: QCA Product ID :0x00000010
Bluetooth: hci0: QCA SOC Version :0x400a0200
Bluetooth: hci0: QCA ROM Version :0x00000200
Bluetooth: hci0: QCA Patch Version:0x00000d2b
Bluetooth: hci0: QCA controller version 0x02000200
Bluetooth: hci0: QCA Downloading qca/htbtfw20.tlv
bluetooth hci0: Direct firmware load for qca/htbtfw20.tlv failed with error -2
Bluetooth: hci0: QCA Failed to request file: qca/htbtfw20.tlv (-2)
Bluetooth: hci0: QCA Failed to download patch (-2)
==================================================================
BUG: KASAN: slab-out-of-bounds in handle_rx_uart+0xa8/0x18c
Write of size 4 at addr ffff279347d578c0 by task swapper/0/0
CPU: 0 PID: 0 Comm: swapper/0 Not tainted 6.1.0-rt5-00350-gb2450b7e00be-dirty #26
Hardware name: Qualcomm Technologies, Inc. Robotics RB5 (DT)
Call trace:
dump_backtrace.part.0+0xe0/0xf0
show_stack+0x18/0x40
dump_stack_lvl+0x8c/0xb8
print_report+0x188/0x488
kasan_report+0xb4/0x100
__asan_store4+0x80/0xa4
handle_rx_uart+0xa8/0x18c
qcom_geni_serial_handle_rx+0x84/0x9c
qcom_geni_serial_isr+0x24c/0x760
__handle_irq_event_percpu+0x108/0x500
handle_irq_event+0x6c/0x110
handle_fasteoi_irq+0x138/0x2cc
generic_handle_domain_irq+0x48/0x64
If the RX FIFO depth changes after probe, be sure to resize the buffer.
CVSS Score
7.1
EPSS Score
0.0
Published
2024-08-21
In the Linux kernel, the following vulnerability has been resolved:
misc: fastrpc: Fix use-after-free race condition for maps
It is possible that in between calling fastrpc_map_get() until
map->fl->lock is taken in fastrpc_free_map(), another thread can call
fastrpc_map_lookup() and get a reference to a map that is about to be
deleted.
Rewrite fastrpc_map_get() to only increase the reference count of a map
if it's non-zero. Propagate this to callers so they can know if a map is
about to be deleted.
Fixes this warning:
refcount_t: addition on 0; use-after-free.
WARNING: CPU: 5 PID: 10100 at lib/refcount.c:25 refcount_warn_saturate
...
Call trace:
refcount_warn_saturate
[fastrpc_map_get inlined]
[fastrpc_map_lookup inlined]
fastrpc_map_create
fastrpc_internal_invoke
fastrpc_device_ioctl
__arm64_sys_ioctl
invoke_syscall
CVSS Score
7.0
EPSS Score
0.0
Published
2024-08-21
In the Linux kernel, the following vulnerability has been resolved:
misc: fastrpc: Don't remove map on creater_process and device_release
Do not remove the map from the list on error path in
fastrpc_init_create_process, instead call fastrpc_map_put, to avoid
use-after-free. Do not remove it on fastrpc_device_release either,
call fastrpc_map_put instead.
The fastrpc_free_map is the only proper place to remove the map.
This is called only after the reference count is 0.
CVSS Score
7.8
EPSS Score
0.0
Published
2024-08-21
In the Linux kernel, the following vulnerability has been resolved:
misc: fastrpc: Fix use-after-free and race in fastrpc_map_find
Currently, there is a race window between the point when the mutex is
unlocked in fastrpc_map_lookup and the reference count increasing
(fastrpc_map_get) in fastrpc_map_find, which can also lead to
use-after-free.
So lets merge fastrpc_map_find into fastrpc_map_lookup which allows us
to both protect the maps list by also taking the &fl->lock spinlock and
the reference count, since the spinlock will be released only after.
Add take_ref argument to make this suitable for all callers.
CVSS Score
7.8
EPSS Score
0.0
Published
2024-08-21
In the Linux kernel, the following vulnerability has been resolved:
wifi: mac80211: sdata can be NULL during AMPDU start
ieee80211_tx_ba_session_handle_start() may get NULL for sdata when a
deauthentication is ongoing.
Here a trace triggering the race with the hostapd test
multi_ap_fronthaul_on_ap:
(gdb) list *drv_ampdu_action+0x46
0x8b16 is in drv_ampdu_action (net/mac80211/driver-ops.c:396).
391 int ret = -EOPNOTSUPP;
392
393 might_sleep();
394
395 sdata = get_bss_sdata(sdata);
396 if (!check_sdata_in_driver(sdata))
397 return -EIO;
398
399 trace_drv_ampdu_action(local, sdata, params);
400
wlan0: moving STA 02:00:00:00:03:00 to state 3
wlan0: associated
wlan0: deauthenticating from 02:00:00:00:03:00 by local choice (Reason: 3=DEAUTH_LEAVING)
wlan3.sta1: Open BA session requested for 02:00:00:00:00:00 tid 0
wlan3.sta1: dropped frame to 02:00:00:00:00:00 (unauthorized port)
wlan0: moving STA 02:00:00:00:03:00 to state 2
wlan0: moving STA 02:00:00:00:03:00 to state 1
wlan0: Removed STA 02:00:00:00:03:00
wlan0: Destroyed STA 02:00:00:00:03:00
BUG: unable to handle page fault for address: fffffffffffffb48
PGD 11814067 P4D 11814067 PUD 11816067 PMD 0
Oops: 0000 [#1] PREEMPT SMP PTI
CPU: 2 PID: 133397 Comm: kworker/u16:1 Tainted: G W 6.1.0-rc8-wt+ #59
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.0-20220807_005459-localhost 04/01/2014
Workqueue: phy3 ieee80211_ba_session_work [mac80211]
RIP: 0010:drv_ampdu_action+0x46/0x280 [mac80211]
Code: 53 48 89 f3 be 89 01 00 00 e8 d6 43 bf ef e8 21 46 81 f0 83 bb a0 1b 00 00 04 75 0e 48 8b 9b 28 0d 00 00 48 81 eb 10 0e 00 00 <8b> 93 58 09 00 00 f6 c2 20 0f 84 3b 01 00 00 8b 05 dd 1c 0f 00 85
RSP: 0018:ffffc900025ebd20 EFLAGS: 00010287
RAX: 0000000000000000 RBX: fffffffffffff1f0 RCX: ffff888102228240
RDX: 0000000080000000 RSI: ffffffff918c5de0 RDI: ffff888102228b40
RBP: ffffc900025ebd40 R08: 0000000000000001 R09: 0000000000000001
R10: 0000000000000001 R11: 0000000000000000 R12: ffff888118c18ec0
R13: 0000000000000000 R14: ffffc900025ebd60 R15: ffff888018b7efb8
FS: 0000000000000000(0000) GS:ffff88817a600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: fffffffffffffb48 CR3: 0000000105228006 CR4: 0000000000170ee0
Call Trace:
<TASK>
ieee80211_tx_ba_session_handle_start+0xd0/0x190 [mac80211]
ieee80211_ba_session_work+0xff/0x2e0 [mac80211]
process_one_work+0x29f/0x620
worker_thread+0x4d/0x3d0
? process_one_work+0x620/0x620
kthread+0xfb/0x120
? kthread_complete_and_exit+0x20/0x20
ret_from_fork+0x22/0x30
</TASK>
CVSS Score
5.5
EPSS Score
0.0
Published
2024-08-21
In the Linux kernel, the following vulnerability has been resolved:
wifi: mac80211: fix initialization of rx->link and rx->link_sta
There are some codepaths that do not initialize rx->link_sta properly. This
causes a crash in places which assume that rx->link_sta is valid if rx->sta
is valid.
One known instance is triggered by __ieee80211_rx_h_amsdu being called from
fast-rx. It results in a crash like this one:
BUG: kernel NULL pointer dereference, address: 00000000000000a8
#PF: supervisor write access in kernel mode
#PF: error_code(0x0002) - not-present page PGD 0 P4D 0
Oops: 0002 [#1] PREEMPT SMP PTI
CPU: 1 PID: 506 Comm: mt76-usb-rx phy Tainted: G E 6.1.0-debian64x+1.7 #3
Hardware name: ZOTAC ZBOX-ID92/ZBOX-IQ01/ZBOX-ID92/ZBOX-IQ01, BIOS B220P007 05/21/2014
RIP: 0010:ieee80211_deliver_skb+0x62/0x1f0 [mac80211]
Code: 00 48 89 04 24 e8 9e a7 c3 df 89 c0 48 03 1c c5 a0 ea 39 a1 4c 01 6b 08 48 ff 03 48
83 7d 28 00 74 11 48 8b 45 30 48 63 55 44 <48> 83 84 d0 a8 00 00 00 01 41 8b 86 c0
11 00 00 8d 50 fd 83 fa 01
RSP: 0018:ffff999040803b10 EFLAGS: 00010286
RAX: 0000000000000000 RBX: ffffb9903f496480 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffff999040803ce0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: ffff8d21828ac900
R13: 000000000000004a R14: ffff8d2198ed89c0 R15: ffff8d2198ed8000
FS: 0000000000000000(0000) GS:ffff8d24afe80000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000000000a8 CR3: 0000000429810002 CR4: 00000000001706e0
Call Trace:
<TASK>
__ieee80211_rx_h_amsdu+0x1b5/0x240 [mac80211]
? ieee80211_prepare_and_rx_handle+0xcdd/0x1320 [mac80211]
? __local_bh_enable_ip+0x3b/0xa0
ieee80211_prepare_and_rx_handle+0xcdd/0x1320 [mac80211]
? prepare_transfer+0x109/0x1a0 [xhci_hcd]
ieee80211_rx_list+0xa80/0xda0 [mac80211]
mt76_rx_complete+0x207/0x2e0 [mt76]
mt76_rx_poll_complete+0x357/0x5a0 [mt76]
mt76u_rx_worker+0x4f5/0x600 [mt76_usb]
? mt76_get_min_avg_rssi+0x140/0x140 [mt76]
__mt76_worker_fn+0x50/0x80 [mt76]
kthread+0xed/0x120
? kthread_complete_and_exit+0x20/0x20
ret_from_fork+0x22/0x30
Since the initialization of rx->link and rx->link_sta is rather convoluted
and duplicated in many places, clean it up by using a helper function to
set it.
[remove unnecessary rx->sta->sta.mlo check]
CVSS Score
5.5
EPSS Score
0.0
Published
2024-08-21