cbcvebase.
CVE-2021-47338
published 2024-05-21

CVE-2021-47338: In the Linux kernel, the following vulnerability has been resolved: fbmem: Do not delete the mode that is still in use The execution of fb_delete_videomode()…

PriorityP338high7.8CVSS 3.1
AVLACLPRLUINSUCHIHAH
EPSS
0.27%
18.7th percentile
In the Linux kernel, the following vulnerability has been resolved: fbmem: Do not delete the mode that is still in use 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

Affected

16 ranges
VendorProductVersion rangeFixed in
debianlinux< linux 5.14.6-1 (bookworm)linux 5.14.6-1 (bookworm)
linuxlinux——
linuxlinux>= 13ff178ccd6d3b8074c542a911300b79c4eec255 < 359311b85ebec7c07c3a08ae2f3def946cad33fa359311b85ebec7c07c3a08ae2f3def946cad33fa
linuxlinux>= 13ff178ccd6d3b8074c542a911300b79c4eec255 < 087bff9acd2ec6db3f61aceb3224bde90fe0f7f8087bff9acd2ec6db3f61aceb3224bde90fe0f7f8
linuxlinux>= 13ff178ccd6d3b8074c542a911300b79c4eec255 < f193509afc7ff37a46862610c93b896044d5b693f193509afc7ff37a46862610c93b896044d5b693
linuxlinux>= 13ff178ccd6d3b8074c542a911300b79c4eec255 < d6e76469157d8f240e5dec6f8411aa8d306b1126d6e76469157d8f240e5dec6f8411aa8d306b1126
linuxlinux>= 13ff178ccd6d3b8074c542a911300b79c4eec255 < 0af778269a522c988ef0b4188556aba97fb420cc0af778269a522c988ef0b4188556aba97fb420cc
linuxlinux_kernel——
linuxlinux_kernel>= 0 < 5.10.70-15.10.70-1
linuxlinux_kernel>= 0 < 5.14.6-15.14.6-1
linuxlinux_kernel>= 0 < 5.14.6-15.14.6-1
linuxlinux_kernel>= 0 < 5.14.6-15.14.6-1
linuxlinux_kernel>= 5.11 < 5.12.195.12.19
linuxlinux_kernel>= 5.13 < 5.13.45.13.4
linuxlinux_kernel>= 5.3 < 5.4.1345.4.134
linuxlinux_kernel>= 5.5 < 5.10.525.10.52

CVSS provenance

nvdv3.17.8HIGHCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
osv7.8HIGH
vendor_debian7.8HIGH
vendor_redhat7.8HIGH
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