Security Vulnerabilities
- CVEs Published In June 2024
In the Linux kernel, the following vulnerability has been resolved:
ALSA: timer: Set lower bound of start tick time
Currently ALSA timer doesn't have the lower limit of the start tick
time, and it allows a very small size, e.g. 1 tick with 1ns resolution
for hrtimer. Such a situation may lead to an unexpected RCU stall,
where the callback repeatedly queuing the expire update, as reported
by fuzzer.
This patch introduces a sanity check of the timer start tick time, so
that the system returns an error when a too small start size is set.
As of this patch, the lower limit is hard-coded to 100us, which is
small enough but can still work somehow.
In the Linux kernel, the following vulnerability has been resolved:
ring-buffer: Fix a race between readers and resize checks
The reader code in rb_get_reader_page() swaps a new reader page into the
ring buffer by doing cmpxchg on old->list.prev->next to point it to the
new page. Following that, if the operation is successful,
old->list.next->prev gets updated too. This means the underlying
doubly-linked list is temporarily inconsistent, page->prev->next or
page->next->prev might not be equal back to page for some page in the
ring buffer.
The resize operation in ring_buffer_resize() can be invoked in parallel.
It calls rb_check_pages() which can detect the described inconsistency
and stop further tracing:
[ 190.271762] ------------[ cut here ]------------
[ 190.271771] WARNING: CPU: 1 PID: 6186 at kernel/trace/ring_buffer.c:1467 rb_check_pages.isra.0+0x6a/0xa0
[ 190.271789] Modules linked in: [...]
[ 190.271991] Unloaded tainted modules: intel_uncore_frequency(E):1 skx_edac(E):1
[ 190.272002] CPU: 1 PID: 6186 Comm: cmd.sh Kdump: loaded Tainted: G E 6.9.0-rc6-default #5 158d3e1e6d0b091c34c3b96bfd99a1c58306d79f
[ 190.272011] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.16.0-0-gd239552c-rebuilt.opensuse.org 04/01/2014
[ 190.272015] RIP: 0010:rb_check_pages.isra.0+0x6a/0xa0
[ 190.272023] Code: [...]
[ 190.272028] RSP: 0018:ffff9c37463abb70 EFLAGS: 00010206
[ 190.272034] RAX: ffff8eba04b6cb80 RBX: 0000000000000007 RCX: ffff8eba01f13d80
[ 190.272038] RDX: ffff8eba01f130c0 RSI: ffff8eba04b6cd00 RDI: ffff8eba0004c700
[ 190.272042] RBP: ffff8eba0004c700 R08: 0000000000010002 R09: 0000000000000000
[ 190.272045] R10: 00000000ffff7f52 R11: ffff8eba7f600000 R12: ffff8eba0004c720
[ 190.272049] R13: ffff8eba00223a00 R14: 0000000000000008 R15: ffff8eba067a8000
[ 190.272053] FS: 00007f1bd64752c0(0000) GS:ffff8eba7f680000(0000) knlGS:0000000000000000
[ 190.272057] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 190.272061] CR2: 00007f1bd6662590 CR3: 000000010291e001 CR4: 0000000000370ef0
[ 190.272070] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[ 190.272073] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[ 190.272077] Call Trace:
[ 190.272098] <TASK>
[ 190.272189] ring_buffer_resize+0x2ab/0x460
[ 190.272199] __tracing_resize_ring_buffer.part.0+0x23/0xa0
[ 190.272206] tracing_resize_ring_buffer+0x65/0x90
[ 190.272216] tracing_entries_write+0x74/0xc0
[ 190.272225] vfs_write+0xf5/0x420
[ 190.272248] ksys_write+0x67/0xe0
[ 190.272256] do_syscall_64+0x82/0x170
[ 190.272363] entry_SYSCALL_64_after_hwframe+0x76/0x7e
[ 190.272373] RIP: 0033:0x7f1bd657d263
[ 190.272381] Code: [...]
[ 190.272385] RSP: 002b:00007ffe72b643f8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
[ 190.272391] RAX: ffffffffffffffda RBX: 0000000000000002 RCX: 00007f1bd657d263
[ 190.272395] RDX: 0000000000000002 RSI: 0000555a6eb538e0 RDI: 0000000000000001
[ 190.272398] RBP: 0000555a6eb538e0 R08: 000000000000000a R09: 0000000000000000
[ 190.272401] R10: 0000555a6eb55190 R11: 0000000000000246 R12: 00007f1bd6662500
[ 190.272404] R13: 0000000000000002 R14: 00007f1bd6667c00 R15: 0000000000000002
[ 190.272412] </TASK>
[ 190.272414] ---[ end trace 0000000000000000 ]---
Note that ring_buffer_resize() calls rb_check_pages() only if the parent
trace_buffer has recording disabled. Recent commit d78ab792705c
("tracing: Stop current tracer when resizing buffer") causes that it is
now always the case which makes it more likely to experience this issue.
The window to hit this race is nonetheless very small. To help
reproducing it, one can add a delay loop in rb_get_reader_page():
ret = rb_head_page_replace(reader, cpu_buffer->reader_page);
if (!ret)
goto spin;
for (unsigned i = 0; i < 1U << 26; i++) /* inserted delay loop */
__asm__ __volatile__ ("" : : : "memory");
rb_list_head(reader->list.next)->prev = &cpu_buffer->reader_page->list;
..
---truncated---
In the Linux kernel, the following vulnerability has been resolved:
ax25: Fix reference count leak issues of ax25_dev
The ax25_addr_ax25dev() and ax25_dev_device_down() exist a reference
count leak issue of the object "ax25_dev".
Memory leak issue in ax25_addr_ax25dev():
The reference count of the object "ax25_dev" can be increased multiple
times in ax25_addr_ax25dev(). This will cause a memory leak.
Memory leak issues in ax25_dev_device_down():
The reference count of ax25_dev is set to 1 in ax25_dev_device_up() and
then increase the reference count when ax25_dev is added to ax25_dev_list.
As a result, the reference count of ax25_dev is 2. But when the device is
shutting down. The ax25_dev_device_down() drops the reference count once
or twice depending on if we goto unlock_put or not, which will cause
memory leak.
As for the issue of ax25_addr_ax25dev(), it is impossible for one pointer
to be on a list twice. So add a break in ax25_addr_ax25dev(). As for the
issue of ax25_dev_device_down(), increase the reference count of ax25_dev
once in ax25_dev_device_up() and decrease the reference count of ax25_dev
after it is removed from the ax25_dev_list.
In the Linux kernel, the following vulnerability has been resolved:
drivers/perf: hisi: hns3: Actually use devm_add_action_or_reset()
pci_alloc_irq_vectors() allocates an irq vector. When devm_add_action()
fails, the irq vector is not freed, which leads to a memory leak.
Replace the devm_add_action with devm_add_action_or_reset to ensure
the irq vector can be destroyed when it fails.
In the Linux kernel, the following vulnerability has been resolved:
block: refine the EOF check in blkdev_iomap_begin
blkdev_iomap_begin rounds down the offset to the logical block size
before stashing it in iomap->offset and checking that it still is
inside the inode size.
Check the i_size check to the raw pos value so that we don't try a
zero size write if iter->pos is unaligned.
In the Linux kernel, the following vulnerability has been resolved:
ALSA: core: Fix NULL module pointer assignment at card init
The commit 81033c6b584b ("ALSA: core: Warn on empty module")
introduced a WARN_ON() for a NULL module pointer passed at snd_card
object creation, and it also wraps the code around it with '#ifdef
MODULE'. This works in most cases, but the devils are always in
details. "MODULE" is defined when the target code (i.e. the sound
core) is built as a module; but this doesn't mean that the caller is
also built-in or not. Namely, when only the sound core is built-in
(CONFIG_SND=y) while the driver is a module (CONFIG_SND_USB_AUDIO=m),
the passed module pointer is ignored even if it's non-NULL, and
card->module remains as NULL. This would result in the missing module
reference up/down at the device open/close, leading to a race with the
code execution after the module removal.
For addressing the bug, move the assignment of card->module again out
of ifdef. The WARN_ON() is still wrapped with ifdef because the
module can be really NULL when all sound drivers are built-in.
Note that we keep 'ifdef MODULE' for WARN_ON(), otherwise it would
lead to a false-positive NULL module check. Admittedly it won't catch
perfectly, i.e. no check is performed when CONFIG_SND=y. But, it's no
real problem as it's only for debugging, and the condition is pretty
rare.
In the Linux kernel, the following vulnerability has been resolved:
crypto: qat - validate slices count returned by FW
The function adf_send_admin_tl_start() enables the telemetry (TL)
feature on a QAT device by sending the ICP_QAT_FW_TL_START message to
the firmware. This triggers the FW to start writing TL data to a DMA
buffer in memory and returns an array containing the number of
accelerators of each type (slices) supported by this HW.
The pointer to this array is stored in the adf_tl_hw_data data
structure called slice_cnt.
The array slice_cnt is then used in the function tl_print_dev_data()
to report in debugfs only statistics about the supported accelerators.
An incorrect value of the elements in slice_cnt might lead to an out
of bounds memory read.
At the moment, there isn't an implementation of FW that returns a wrong
value, but for robustness validate the slice count array returned by FW.
In the Linux kernel, the following vulnerability has been resolved:
macintosh/via-macii: Fix "BUG: sleeping function called from invalid context"
The via-macii ADB driver calls request_irq() after disabling hard
interrupts. But disabling interrupts isn't necessary here because the
VIA shift register interrupt was masked during VIA1 initialization.
In the Linux kernel, the following vulnerability has been resolved:
net/mlx5e: Fix netif state handling
mlx5e_suspend cleans resources only if netif_device_present() returns
true. However, mlx5e_resume changes the state of netif, via
mlx5e_nic_enable, only if reg_state == NETREG_REGISTERED.
In the below case, the above leads to NULL-ptr Oops[1] and memory
leaks:
mlx5e_probe
_mlx5e_resume
mlx5e_attach_netdev
mlx5e_nic_enable <-- netdev not reg, not calling netif_device_attach()
register_netdev <-- failed for some reason.
ERROR_FLOW:
_mlx5e_suspend <-- netif_device_present return false, resources aren't freed :(
Hence, clean resources in this case as well.
[1]
BUG: kernel NULL pointer dereference, address: 0000000000000000
PGD 0 P4D 0
Oops: 0010 [#1] SMP
CPU: 2 PID: 9345 Comm: test-ovs-ct-gen Not tainted 6.5.0_for_upstream_min_debug_2023_09_05_16_01 #1
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014
RIP: 0010:0x0
Code: Unable to access opcode bytes at0xffffffffffffffd6.
RSP: 0018:ffff888178aaf758 EFLAGS: 00010246
Call Trace:
<TASK>
? __die+0x20/0x60
? page_fault_oops+0x14c/0x3c0
? exc_page_fault+0x75/0x140
? asm_exc_page_fault+0x22/0x30
notifier_call_chain+0x35/0xb0
blocking_notifier_call_chain+0x3d/0x60
mlx5_blocking_notifier_call_chain+0x22/0x30 [mlx5_core]
mlx5_core_uplink_netdev_event_replay+0x3e/0x60 [mlx5_core]
mlx5_mdev_netdev_track+0x53/0x60 [mlx5_ib]
mlx5_ib_roce_init+0xc3/0x340 [mlx5_ib]
__mlx5_ib_add+0x34/0xd0 [mlx5_ib]
mlx5r_probe+0xe1/0x210 [mlx5_ib]
? auxiliary_match_id+0x6a/0x90
auxiliary_bus_probe+0x38/0x80
? driver_sysfs_add+0x51/0x80
really_probe+0xc9/0x3e0
? driver_probe_device+0x90/0x90
__driver_probe_device+0x80/0x160
driver_probe_device+0x1e/0x90
__device_attach_driver+0x7d/0x100
bus_for_each_drv+0x80/0xd0
__device_attach+0xbc/0x1f0
bus_probe_device+0x86/0xa0
device_add+0x637/0x840
__auxiliary_device_add+0x3b/0xa0
add_adev+0xc9/0x140 [mlx5_core]
mlx5_rescan_drivers_locked+0x22a/0x310 [mlx5_core]
mlx5_register_device+0x53/0xa0 [mlx5_core]
mlx5_init_one_devl_locked+0x5c4/0x9c0 [mlx5_core]
mlx5_init_one+0x3b/0x60 [mlx5_core]
probe_one+0x44c/0x730 [mlx5_core]
local_pci_probe+0x3e/0x90
pci_device_probe+0xbf/0x210
? kernfs_create_link+0x5d/0xa0
? sysfs_do_create_link_sd+0x60/0xc0
really_probe+0xc9/0x3e0
? driver_probe_device+0x90/0x90
__driver_probe_device+0x80/0x160
driver_probe_device+0x1e/0x90
__device_attach_driver+0x7d/0x100
bus_for_each_drv+0x80/0xd0
__device_attach+0xbc/0x1f0
pci_bus_add_device+0x54/0x80
pci_iov_add_virtfn+0x2e6/0x320
sriov_enable+0x208/0x420
mlx5_core_sriov_configure+0x9e/0x200 [mlx5_core]
sriov_numvfs_store+0xae/0x1a0
kernfs_fop_write_iter+0x10c/0x1a0
vfs_write+0x291/0x3c0
ksys_write+0x5f/0xe0
do_syscall_64+0x3d/0x90
entry_SYSCALL_64_after_hwframe+0x46/0xb0
CR2: 0000000000000000
---[ end trace 0000000000000000 ]---
In the Linux kernel, the following vulnerability has been resolved:
wifi: mt76: connac: check for null before dereferencing
The wcid can be NULL. It should be checked for validity before
dereferencing it to avoid crash.