In the Linux kernel, the following vulnerability has been resolved:
usb: gadget: u_serial: Fix the issue that gs_start_io crashed due to accessing null pointer
Considering that in some extreme cases,
when u_serial driver is accessed by multiple threads,
Thread A is executing the open operation and calling the gs_open,
Thread B is executing the disconnect operation and calling the
gserial_disconnect function,The port->port_usb pointer will be set to NULL.
E.g.
Thread A Thread B
gs_open() gadget_unbind_driver()
gs_start_io() composite_disconnect()
gs_start_rx() gserial_disconnect()
... ...
spin_unlock(&port->port_lock)
status = usb_ep_queue() spin_lock(&port->port_lock)
spin_lock(&port->port_lock) port->port_usb = NULL
gs_free_requests(port->port_usb->in) spin_unlock(&port->port_lock)
Crash
This causes thread A to access a null pointer (port->port_usb is null)
when calling the gs_free_requests function, causing a crash.
If port_usb is NULL, the release request will be skipped as it
will be done by gserial_disconnect.
So add a null pointer check to gs_start_io before attempting
to access the value of the pointer port->port_usb.
Call trace:
gs_start_io+0x164/0x25c
gs_open+0x108/0x13c
tty_open+0x314/0x638
chrdev_open+0x1b8/0x258
do_dentry_open+0x2c4/0x700
vfs_open+0x2c/0x3c
path_openat+0xa64/0xc60
do_filp_open+0xb8/0x164
do_sys_openat2+0x84/0xf0
__arm64_sys_openat+0x70/0x9c
invoke_syscall+0x58/0x114
el0_svc_common+0x80/0xe0
do_el0_svc+0x1c/0x28
el0_svc+0x38/0x68
Metrics
Affected Vendors & Products
References
History
Mon, 06 Jan 2025 18:30:00 +0000
Type | Values Removed | Values Added |
---|---|---|
First Time appeared |
Linux
Linux linux Kernel |
|
Weaknesses | CWE-476 | |
CPEs | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* cpe:2.3:o:linux:linux_kernel:6.13:rc1:*:*:*:*:*:* cpe:2.3:o:linux:linux_kernel:6.13:rc2:*:*:*:*:*:* |
|
Vendors & Products |
Linux
Linux linux Kernel |
Sat, 28 Dec 2024 13:30:00 +0000
Type | Values Removed | Values Added |
---|---|---|
References |
| |
Metrics |
threat_severity
|
cvssV3_1
|
Fri, 27 Dec 2024 15:15:00 +0000
Type | Values Removed | Values Added |
---|---|---|
Description | In the Linux kernel, the following vulnerability has been resolved: usb: gadget: u_serial: Fix the issue that gs_start_io crashed due to accessing null pointer Considering that in some extreme cases, when u_serial driver is accessed by multiple threads, Thread A is executing the open operation and calling the gs_open, Thread B is executing the disconnect operation and calling the gserial_disconnect function,The port->port_usb pointer will be set to NULL. E.g. Thread A Thread B gs_open() gadget_unbind_driver() gs_start_io() composite_disconnect() gs_start_rx() gserial_disconnect() ... ... spin_unlock(&port->port_lock) status = usb_ep_queue() spin_lock(&port->port_lock) spin_lock(&port->port_lock) port->port_usb = NULL gs_free_requests(port->port_usb->in) spin_unlock(&port->port_lock) Crash This causes thread A to access a null pointer (port->port_usb is null) when calling the gs_free_requests function, causing a crash. If port_usb is NULL, the release request will be skipped as it will be done by gserial_disconnect. So add a null pointer check to gs_start_io before attempting to access the value of the pointer port->port_usb. Call trace: gs_start_io+0x164/0x25c gs_open+0x108/0x13c tty_open+0x314/0x638 chrdev_open+0x1b8/0x258 do_dentry_open+0x2c4/0x700 vfs_open+0x2c/0x3c path_openat+0xa64/0xc60 do_filp_open+0xb8/0x164 do_sys_openat2+0x84/0xf0 __arm64_sys_openat+0x70/0x9c invoke_syscall+0x58/0x114 el0_svc_common+0x80/0xe0 do_el0_svc+0x1c/0x28 el0_svc+0x38/0x68 | |
Title | usb: gadget: u_serial: Fix the issue that gs_start_io crashed due to accessing null pointer | |
References |
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MITRE
Status: PUBLISHED
Assigner: Linux
Published: 2024-12-27T15:06:31.611Z
Updated: 2024-12-27T15:06:31.611Z
Reserved: 2024-12-27T15:00:39.844Z
Link: CVE-2024-56670
Vulnrichment
No data.
NVD
Status : Analyzed
Published: 2024-12-27T15:15:26.890
Modified: 2025-01-06T18:13:02.807
Link: CVE-2024-56670
Redhat