Security Vulnerabilities
- CVEs Published In May 2024
In the Linux kernel, the following vulnerability has been resolved:
pstore/platform: Add check for kstrdup
Add check for the return value of kstrdup() and return the error
if it fails in order to avoid NULL pointer dereference.
In the Linux kernel, the following vulnerability has been resolved:
clk: mediatek: clk-mt6765: Add check for mtk_alloc_clk_data
Add the check for the return value of mtk_alloc_clk_data() in order to
avoid NULL pointer dereference.
In the Linux kernel, the following vulnerability has been resolved:
soc: qcom: llcc: Handle a second device without data corruption
Usually there is only one llcc device. But if there were a second, even
a failed probe call would modify the global drv_data pointer. So check
if drv_data is valid before overwriting it.
In the Linux kernel, the following vulnerability has been resolved:
tty: n_gsm: fix race condition in status line change on dead connections
gsm_cleanup_mux() cleans up the gsm by closing all DLCIs, stopping all
timers, removing the virtual tty devices and clearing the data queues.
This procedure, however, may cause subsequent changes of the virtual modem
status lines of a DLCI. More data is being added the outgoing data queue
and the deleted kick timer is restarted to handle this. At this point many
resources have already been removed by the cleanup procedure. Thus, a
kernel panic occurs.
Fix this by proving in gsm_modem_update() that the cleanup procedure has
not been started and the mux is still alive.
Note that writing to a virtual tty is already protected by checks against
the DLCI specific connection state.
In the Linux kernel, the following vulnerability has been resolved:
cxl/mem: Fix shutdown order
Ira reports that removing cxl_mock_mem causes a crash with the following
trace:
BUG: kernel NULL pointer dereference, address: 0000000000000044
[..]
RIP: 0010:cxl_region_decode_reset+0x7f/0x180 [cxl_core]
[..]
Call Trace:
<TASK>
cxl_region_detach+0xe8/0x210 [cxl_core]
cxl_decoder_kill_region+0x27/0x40 [cxl_core]
cxld_unregister+0x29/0x40 [cxl_core]
devres_release_all+0xb8/0x110
device_unbind_cleanup+0xe/0x70
device_release_driver_internal+0x1d2/0x210
bus_remove_device+0xd7/0x150
device_del+0x155/0x3e0
device_unregister+0x13/0x60
devm_release_action+0x4d/0x90
? __pfx_unregister_port+0x10/0x10 [cxl_core]
delete_endpoint+0x121/0x130 [cxl_core]
devres_release_all+0xb8/0x110
device_unbind_cleanup+0xe/0x70
device_release_driver_internal+0x1d2/0x210
bus_remove_device+0xd7/0x150
device_del+0x155/0x3e0
? lock_release+0x142/0x290
cdev_device_del+0x15/0x50
cxl_memdev_unregister+0x54/0x70 [cxl_core]
This crash is due to the clearing out the cxl_memdev's driver context
(@cxlds) before the subsystem is done with it. This is ultimately due to
the region(s), that this memdev is a member, being torn down and expecting
to be able to de-reference @cxlds, like here:
static int cxl_region_decode_reset(struct cxl_region *cxlr, int count)
...
if (cxlds->rcd)
goto endpoint_reset;
...
Fix it by keeping the driver context valid until memdev-device
unregistration, and subsequently the entire stack of related
dependencies, unwinds.
In the Linux kernel, the following vulnerability has been resolved:
media: hantro: Check whether reset op is defined before use
The i.MX8MM/N/P does not define the .reset op since reset of the VPU is
done by genpd. Check whether the .reset op is defined before calling it
to avoid NULL pointer dereference.
Note that the Fixes tag is set to the commit which removed the reset op
from i.MX8M Hantro G2 implementation, this is because before this commit
all the implementations did define the .reset op.
In the Linux kernel, the following vulnerability has been resolved:
IB/mlx5: Fix init stage error handling to avoid double free of same QP and UAF
In the unlikely event that workqueue allocation fails and returns NULL in
mlx5_mkey_cache_init(), delete the call to
mlx5r_umr_resource_cleanup() (which frees the QP) in
mlx5_ib_stage_post_ib_reg_umr_init(). This will avoid attempted double
free of the same QP when __mlx5_ib_add() does its cleanup.
Resolves a splat:
Syzkaller reported a UAF in ib_destroy_qp_user
workqueue: Failed to create a rescuer kthread for wq "mkey_cache": -EINTR
infiniband mlx5_0: mlx5_mkey_cache_init:981:(pid 1642):
failed to create work queue
infiniband mlx5_0: mlx5_ib_stage_post_ib_reg_umr_init:4075:(pid 1642):
mr cache init failed -12
==================================================================
BUG: KASAN: slab-use-after-free in ib_destroy_qp_user (drivers/infiniband/core/verbs.c:2073)
Read of size 8 at addr ffff88810da310a8 by task repro_upstream/1642
Call Trace:
<TASK>
kasan_report (mm/kasan/report.c:590)
ib_destroy_qp_user (drivers/infiniband/core/verbs.c:2073)
mlx5r_umr_resource_cleanup (drivers/infiniband/hw/mlx5/umr.c:198)
__mlx5_ib_add (drivers/infiniband/hw/mlx5/main.c:4178)
mlx5r_probe (drivers/infiniband/hw/mlx5/main.c:4402)
...
</TASK>
Allocated by task 1642:
__kmalloc (./include/linux/kasan.h:198 mm/slab_common.c:1026
mm/slab_common.c:1039)
create_qp (./include/linux/slab.h:603 ./include/linux/slab.h:720
./include/rdma/ib_verbs.h:2795 drivers/infiniband/core/verbs.c:1209)
ib_create_qp_kernel (drivers/infiniband/core/verbs.c:1347)
mlx5r_umr_resource_init (drivers/infiniband/hw/mlx5/umr.c:164)
mlx5_ib_stage_post_ib_reg_umr_init (drivers/infiniband/hw/mlx5/main.c:4070)
__mlx5_ib_add (drivers/infiniband/hw/mlx5/main.c:4168)
mlx5r_probe (drivers/infiniband/hw/mlx5/main.c:4402)
...
Freed by task 1642:
__kmem_cache_free (mm/slub.c:1826 mm/slub.c:3809 mm/slub.c:3822)
ib_destroy_qp_user (drivers/infiniband/core/verbs.c:2112)
mlx5r_umr_resource_cleanup (drivers/infiniband/hw/mlx5/umr.c:198)
mlx5_ib_stage_post_ib_reg_umr_init (drivers/infiniband/hw/mlx5/main.c:4076
drivers/infiniband/hw/mlx5/main.c:4065)
__mlx5_ib_add (drivers/infiniband/hw/mlx5/main.c:4168)
mlx5r_probe (drivers/infiniband/hw/mlx5/main.c:4402)
...
In the Linux kernel, the following vulnerability has been resolved:
f2fs: compress: fix to avoid use-after-free on dic
Call trace:
__memcpy+0x128/0x250
f2fs_read_multi_pages+0x940/0xf7c
f2fs_mpage_readpages+0x5a8/0x624
f2fs_readahead+0x5c/0x110
page_cache_ra_unbounded+0x1b8/0x590
do_sync_mmap_readahead+0x1dc/0x2e4
filemap_fault+0x254/0xa8c
f2fs_filemap_fault+0x2c/0x104
__do_fault+0x7c/0x238
do_handle_mm_fault+0x11bc/0x2d14
do_mem_abort+0x3a8/0x1004
el0_da+0x3c/0xa0
el0t_64_sync_handler+0xc4/0xec
el0t_64_sync+0x1b4/0x1b8
In f2fs_read_multi_pages(), once f2fs_decompress_cluster() was called if
we hit cached page in compress_inode's cache, dic may be released, it needs
break the loop rather than continuing it, in order to avoid accessing
invalid dic pointer.
In the Linux kernel, the following vulnerability has been resolved:
hid: cp2112: Fix duplicate workqueue initialization
Previously the cp2112 driver called INIT_DELAYED_WORK within
cp2112_gpio_irq_startup, resulting in duplicate initilizations of the
workqueue on subsequent IRQ startups following an initial request. This
resulted in a warning in set_work_data in workqueue.c, as well as a rare
NULL dereference within process_one_work in workqueue.c.
Initialize the workqueue within _probe instead.
In the Linux kernel, the following vulnerability has been resolved:
padata: Fix refcnt handling in padata_free_shell()
In a high-load arm64 environment, the pcrypt_aead01 test in LTP can lead
to system UAF (Use-After-Free) issues. Due to the lengthy analysis of
the pcrypt_aead01 function call, I'll describe the problem scenario
using a simplified model:
Suppose there's a user of padata named `user_function` that adheres to
the padata requirement of calling `padata_free_shell` after `serial()`
has been invoked, as demonstrated in the following code:
```c
struct request {
struct padata_priv padata;
struct completion *done;
};
void parallel(struct padata_priv *padata) {
do_something();
}
void serial(struct padata_priv *padata) {
struct request *request = container_of(padata,
struct request,
padata);
complete(request->done);
}
void user_function() {
DECLARE_COMPLETION(done)
padata->parallel = parallel;
padata->serial = serial;
padata_do_parallel();
wait_for_completion(&done);
padata_free_shell();
}
```
In the corresponding padata.c file, there's the following code:
```c
static void padata_serial_worker(struct work_struct *serial_work) {
...
cnt = 0;
while (!list_empty(&local_list)) {
...
padata->serial(padata);
cnt++;
}
local_bh_enable();
if (refcount_sub_and_test(cnt, &pd->refcnt))
padata_free_pd(pd);
}
```
Because of the high system load and the accumulation of unexecuted
softirq at this moment, `local_bh_enable()` in padata takes longer
to execute than usual. Subsequently, when accessing `pd->refcnt`,
`pd` has already been released by `padata_free_shell()`, resulting
in a UAF issue with `pd->refcnt`.
The fix is straightforward: add `refcount_dec_and_test` before calling
`padata_free_pd` in `padata_free_shell`.