Zhen Lei 89f94b88f4 fbmem: Do not delete the mode that is still in use ... commit 0af778269a upstream. The execution of fb_delete_videomode() is not based on the result of the previous fbcon_mode_deleted(). As a result, the mode is directly deleted, regardless of whether it is still in use, which may cause UAF. ================================================================== BUG: KASAN: use-after-free in fb_mode_is_equal+0x36e/0x5e0 \ drivers/video/fbdev/core/modedb.c:924 Read of size 4 at addr ffff88807e0ddb1c by task syz-executor.0/18962 CPU: 2 PID: 18962 Comm: syz-executor.0 Not tainted 5.10.45-rc1+ #3 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS ... Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x137/0x1be lib/dump_stack.c:118 print_address_description+0x6c/0x640 mm/kasan/report.c:385 __kasan_report mm/kasan/report.c:545 [inline] kasan_report+0x13d/0x1e0 mm/kasan/report.c:562 fb_mode_is_equal+0x36e/0x5e0 drivers/video/fbdev/core/modedb.c:924 fbcon_mode_deleted+0x16a/0x220 drivers/video/fbdev/core/fbcon.c:2746 fb_set_var+0x1e1/0xdb0 drivers/video/fbdev/core/fbmem.c:975 do_fb_ioctl+0x4d9/0x6e0 drivers/video/fbdev/core/fbmem.c:1108 vfs_ioctl fs/ioctl.c:48 [inline] __do_sys_ioctl fs/ioctl.c:753 [inline] __se_sys_ioctl+0xfb/0x170 fs/ioctl.c:739 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Freed by task 18960: kasan_save_stack mm/kasan/common.c:48 [inline] kasan_set_track+0x3d/0x70 mm/kasan/common.c:56 kasan_set_free_info+0x17/0x30 mm/kasan/generic.c:355 __kasan_slab_free+0x108/0x140 mm/kasan/common.c:422 slab_free_hook mm/slub.c:1541 [inline] slab_free_freelist_hook+0xd6/0x1a0 mm/slub.c:1574 slab_free mm/slub.c:3139 [inline] kfree+0xca/0x3d0 mm/slub.c:4121 fb_delete_videomode+0x56a/0x820 drivers/video/fbdev/core/modedb.c:1104 fb_set_var+0x1f3/0xdb0 drivers/video/fbdev/core/fbmem.c:978 do_fb_ioctl+0x4d9/0x6e0 drivers/video/fbdev/core/fbmem.c:1108 vfs_ioctl fs/ioctl.c:48 [inline] __do_sys_ioctl fs/ioctl.c:753 [inline] __se_sys_ioctl+0xfb/0x170 fs/ioctl.c:739 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Fixes: 13ff178ccd ("fbcon: Call fbcon_mode_deleted/new_modelist directly") Signed-off-by: Zhen Lei <thunder.leizhen@huawei.com> Cc: <stable@vger.kernel.org> # v5.3+ Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch> Link: https://patchwork.freedesktop.org/patch/msgid/20210712085544.2828-1-thunder.leizhen@huawei.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Xinghui Li <korantli@tencent.com>		2024-06-11 21:18:45 +08:00
..
backlight	ock: sync codes to ock 5.4.119-20.0009.21	2024-06-11 20:27:38 +08:00
console	ock: sync codes to ock 5.4.119-20.0009.21	2024-06-11 20:27:38 +08:00
fbdev	fbmem: Do not delete the mode that is still in use	2024-06-11 21:18:45 +08:00
logo	video/logo: do not generate unneeded logo C files	2019-10-05 15:29:49 +09:00
Kconfig	treewide: Add SPDX license identifier - Makefile/Kconfig	2019-05-21 10:50:46 +02:00
Makefile	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
display_timing.c	treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 428	2019-06-05 17:37:16 +02:00
hdmi.c	tkernel: add base tlinux kernel interfaces	2024-06-11 20:09:33 +08:00
of_display_timing.c	video: of: display_timing: Don't yell if no timing node is present	2019-07-26 16:32:26 +02:00
of_videomode.c	treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 428	2019-06-05 17:37:16 +02:00
vgastate.c	Video: vgastate: fixed a spacing coding style	2018-10-08 12:57:35 +02:00
videomode.c	treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 428	2019-06-05 17:37:16 +02:00