In the Linux kernel, the following vulnerability has been resolved:
ntb: ntb_hw_switchtec: Fix use after free vulnerability in switchtec_ntb_remove due to race condition
In the switchtec_ntb_add function, it can call switchtec_ntb_init_sndev
function, then &sndev->check_link_status_work is bound with
check_link_status_work. switchtec_ntb_link_notification may be called
to start the work.
If we remove the module which will call switchtec_ntb_remove to make
cleanup, it will free sndev through kfree(sndev), while the work
mentioned above will be used. The sequence of operations that may lead
to a UAF bug is as follows:
CPU0 CPU1
| check_link_status_work
switchtec_ntb_remove |
kfree(sndev); |
| if (sndev->link_force_down)
| // use sndev
Fix it by ensuring that the work is canceled before proceeding with
the cleanup in switchtec_ntb_remove.
In the Linux kernel, the following vulnerability has been resolved:
i3c: master: cdns: Fix use after free vulnerability in cdns_i3c_master Driver Due to Race Condition
In the cdns_i3c_master_probe function, &master->hj_work is bound with
cdns_i3c_master_hj. And cdns_i3c_master_interrupt can call
cnds_i3c_master_demux_ibis function to start the work.
If we remove the module which will call cdns_i3c_master_remove to
make cleanup, it will free master->base through i3c_master_unregister
while the work mentioned above will be used. The sequence of operations
that may lead to a UAF bug is as follows:
CPU0 CPU1
| cdns_i3c_master_hj
cdns_i3c_master_remove |
i3c_master_unregister(&master->base) |
device_unregister(&master->dev) |
device_release |
//free master->base |
| i3c_master_do_daa(&master->base)
| //use master->base
Fix it by ensuring that the work is canceled before proceeding with
the cleanup in cdns_i3c_master_remove.
In the Linux kernel, the following vulnerability has been resolved:
RDMA/rtrs-srv: Avoid null pointer deref during path establishment
For RTRS path establishment, RTRS client initiates and completes con_num
of connections. After establishing all its connections, the information
is exchanged between the client and server through the info_req message.
During this exchange, it is essential that all connections have been
established, and the state of the RTRS srv path is CONNECTED.
So add these sanity checks, to make sure we detect and abort process in
error scenarios to avoid null pointer deref.
In the Linux kernel, the following vulnerability has been resolved:
fbcon: Fix a NULL pointer dereference issue in fbcon_putcs
syzbot has found a NULL pointer dereference bug in fbcon.
Here is the simplified C reproducer:
struct param {
uint8_t type;
struct tiocl_selection ts;
};
int main()
{
struct fb_con2fbmap con2fb;
struct param param;
int fd = open("/dev/fb1", 0, 0);
con2fb.console = 0x19;
con2fb.framebuffer = 0;
ioctl(fd, FBIOPUT_CON2FBMAP, &con2fb);
param.type = 2;
param.ts.xs = 0; param.ts.ys = 0;
param.ts.xe = 0; param.ts.ye = 0;
param.ts.sel_mode = 0;
int fd1 = open("/dev/tty1", O_RDWR, 0);
ioctl(fd1, TIOCLINUX, ¶m);
con2fb.console = 1;
con2fb.framebuffer = 0;
ioctl(fd, FBIOPUT_CON2FBMAP, &con2fb);
return 0;
}
After calling ioctl(fd1, TIOCLINUX, ¶m), the subsequent ioctl(fd, FBIOPUT_CON2FBMAP, &con2fb)
causes the kernel to follow a different execution path:
set_con2fb_map
-> con2fb_init_display
-> fbcon_set_disp
-> redraw_screen
-> hide_cursor
-> clear_selection
-> highlight
-> invert_screen
-> do_update_region
-> fbcon_putcs
-> ops->putcs
Since ops->putcs is a NULL pointer, this leads to a kernel panic.
To prevent this, we need to call set_blitting_type() within set_con2fb_map()
to properly initialize ops->putcs.
In the Linux kernel, the following vulnerability has been resolved:
drm/amd/display: Check null pointer before dereferencing se
[WHAT & HOW]
se is null checked previously in the same function, indicating
it might be null; therefore, it must be checked when used again.
This fixes 1 FORWARD_NULL issue reported by Coverity.
In the Linux kernel, the following vulnerability has been resolved:
driver core: bus: Fix double free in driver API bus_register()
For bus_register(), any error which happens after kset_register() will
cause that @priv are freed twice, fixed by setting @priv with NULL after
the first free.
In the Linux kernel, the following vulnerability has been resolved:
usb: typec: tipd: Free IRQ only if it was requested before
In polling mode, if no IRQ was requested there is no need to free it.
Call devm_free_irq() only if client->irq is set. This fixes the warning
caused by the tps6598x module removal:
WARNING: CPU: 2 PID: 333 at kernel/irq/devres.c:144 devm_free_irq+0x80/0x8c
...
...
Call trace:
devm_free_irq+0x80/0x8c
tps6598x_remove+0x28/0x88 [tps6598x]
i2c_device_remove+0x2c/0x9c
device_remove+0x4c/0x80
device_release_driver_internal+0x1cc/0x228
driver_detach+0x50/0x98
bus_remove_driver+0x6c/0xbc
driver_unregister+0x30/0x60
i2c_del_driver+0x54/0x64
tps6598x_i2c_driver_exit+0x18/0xc3c [tps6598x]
__arm64_sys_delete_module+0x184/0x264
invoke_syscall+0x48/0x110
el0_svc_common.constprop.0+0xc8/0xe8
do_el0_svc+0x20/0x2c
el0_svc+0x28/0x98
el0t_64_sync_handler+0x13c/0x158
el0t_64_sync+0x190/0x194
In the Linux kernel, the following vulnerability has been resolved:
serial: protect uart_port_dtr_rts() in uart_shutdown() too
Commit af224ca2df29 (serial: core: Prevent unsafe uart port access, part
3) added few uport == NULL checks. It added one to uart_shutdown(), so
the commit assumes, uport can be NULL in there. But right after that
protection, there is an unprotected "uart_port_dtr_rts(uport, false);"
call. That is invoked only if HUPCL is set, so I assume that is the
reason why we do not see lots of these reports.
Or it cannot be NULL at this point at all for some reason :P.
Until the above is investigated, stay on the safe side and move this
dereference to the if too.
I got this inconsistency from Coverity under CID 1585130. Thanks.