CVE-2022-48993

In the Linux kernel, the following vulnerability has been resolved:

fbcon: Use kzalloc() in fbcon_prepare_logo()

A kernel built with syzbot's config file reported that

scr_memcpyw(q, save, array3_size(logo_lines, new_cols, 2))

causes uninitialized "save" to be copied.

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[drm] Initialized vgem 1.0.0 20120112 for vgem on minor 0
[drm] Initialized vkms 1.0.0 20180514 for vkms on minor 1
Console: switching to colour frame buffer device 128x48
=====================================================
BUG: KMSAN: uninit-value in do_update_region+0x4b8/0xba0
do_update_region+0x4b8/0xba0
update_region+0x40d/0x840
fbcon_switch+0x3364/0x35e0
redraw_screen+0xae3/0x18a0
do_bind_con_driver+0x1cb3/0x1df0
do_take_over_console+0x11cb/0x13f0
fbcon_fb_registered+0xacc/0xfd0
register_framebuffer+0x1179/0x1320
__drm_fb_helper_initial_config_and_unlock+0x23ad/0x2b40
drm_fbdev_client_hotplug+0xbea/0xda0
drm_fbdev_generic_setup+0x65e/0x9d0
vkms_init+0x9f3/0xc76
(...snipped...)

Uninit was stored to memory at:
fbcon_prepare_logo+0x143b/0x1940
fbcon_init+0x2c1b/0x31c0
visual_init+0x3e7/0x820
do_bind_con_driver+0x14a4/0x1df0
do_take_over_console+0x11cb/0x13f0
fbcon_fb_registered+0xacc/0xfd0
register_framebuffer+0x1179/0x1320
__drm_fb_helper_initial_config_and_unlock+0x23ad/0x2b40
drm_fbdev_client_hotplug+0xbea/0xda0
drm_fbdev_generic_setup+0x65e/0x9d0
vkms_init+0x9f3/0xc76
(...snipped...)

Uninit was created at:
__kmem_cache_alloc_node+0xb69/0x1020
__kmalloc+0x379/0x680
fbcon_prepare_logo+0x704/0x1940
fbcon_init+0x2c1b/0x31c0
visual_init+0x3e7/0x820
do_bind_con_driver+0x14a4/0x1df0
do_take_over_console+0x11cb/0x13f0
fbcon_fb_registered+0xacc/0xfd0
register_framebuffer+0x1179/0x1320
__drm_fb_helper_initial_config_and_unlock+0x23ad/0x2b40
drm_fbdev_client_hotplug+0xbea/0xda0
drm_fbdev_generic_setup+0x65e/0x9d0
vkms_init+0x9f3/0xc76
(...snipped...)

CPU: 2 PID: 1 Comm: swapper/0 Not tainted 6.1.0-rc4-00356-g8f2975c2bb4c #924
Hardware name: innotek GmbH VirtualBox/VirtualBox, BIOS VirtualBox 12/01/2006
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