CVE-2024-26798
- Source
- https://nvd.nist.gov/vuln/detail/CVE-2024-26798
- Import Source
- https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2024-26798.json
- JSON Data
- https://api.test.osv.dev/v1/vulns/CVE-2024-26798
- Downstream
- Related
- Published
- 2024-04-04T08:20:27Z
- Modified
- 2025-10-09T06:06:11.160992Z
- Summary
- fbcon: always restore the old font data in fbcon_do_set_font()
- Details
-
In the Linux kernel, the following vulnerability has been resolved:
fbcon: always restore the old font data in fbcondoset_font()
Commit a5a923038d70 (fbdev: fbcon: Properly revert changes when vcresize() failed) started restoring old font data upon failure (of vcresize()). But it performs so only for user fonts. It means that the "system"/internal fonts are not restored at all. So in result, the very first call to fbcondosetfont() performs no restore at all upon failing vcresize().
This can be reproduced by Syzkaller to crash the system on the next invocation of fontget(). It's rather hard to hit the allocation failure in vcresize() on the first fontset(), but not impossible. Esp. if fault injection is used to aid the execution/failure. It was demonstrated by Sirius: BUG: unable to handle page fault for address: fffffffffffffff8 #PF: supervisor read access in kernel mode #PF: errorcode(0x0000) - not-present page PGD cb7b067 P4D cb7b067 PUD cb7d067 PMD 0 Oops: 0000 [#1] PREEMPT SMP KASAN CPU: 1 PID: 8007 Comm: poc Not tainted 6.7.0-g9d1694dc91ce #20 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.15.0-1 04/01/2014 RIP: 0010:fbcongetfont+0x229/0x800 drivers/video/fbdev/core/fbcon.c:2286 Call Trace: <TASK> confontget drivers/tty/vt/vt.c:4558 [inline] confontop+0x1fc/0xf20 drivers/tty/vt/vt.c:4673 vtkioctl drivers/tty/vt/vtioctl.c:474 [inline] vtioctl+0x632/0x2ec0 drivers/tty/vt/vtioctl.c:752 ttyioctl+0x6f8/0x1570 drivers/tty/ttyio.c:2803 vfsioctl fs/ioctl.c:51 [inline] ...
So restore the font data in any case, not only for user fonts. Note the later 'if' is now protected by 'olduserfont' and not 'olddata' as the latter is always set now. (And it is supposed to be non-NULL. Otherwise we would see the bug above again.)
- References
-
- https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
- https://git.kernel.org/stable/c/00d6a284fcf3fad1b7e1b5bc3cd87cbfb60ce03f
- https://git.kernel.org/stable/c/20a4b5214f7bee13c897477168c77bbf79683c3d
- https://git.kernel.org/stable/c/2f91a96b892fab2f2543b4a55740c5bee36b1a6b
- https://git.kernel.org/stable/c/73a6bd68a1342f3a44cac9dffad81ad6a003e520
- https://git.kernel.org/stable/c/a2c881413dcc5d801bdc9535e51270cc88cb9cd8
Affected packages
Git / git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
Affected ranges
- Type
- GIT
- Repo
- https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
- Events
-
Introducedebd6f886aa2447fcfcdce5450c9e1028e1d681bbFixed20a4b5214f7bee13c897477168c77bbf79683c3d
- Type
- GIT
- Repo
- https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
- Events
-
Introduceda5a923038d70d2d4a86cb4e3f32625a5ee6e7e24Fixed2f91a96b892fab2f2543b4a55740c5bee36b1a6b
- Type
- GIT
- Repo
- https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
- Events
-
Introduceda5a923038d70d2d4a86cb4e3f32625a5ee6e7e24Fixed73a6bd68a1342f3a44cac9dffad81ad6a003e520
- Type
- GIT
- Repo
- https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
- Events
-
Introduceda5a923038d70d2d4a86cb4e3f32625a5ee6e7e24Fixeda2c881413dcc5d801bdc9535e51270cc88cb9cd8
- Type
- GIT
- Repo
- https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
- Events
-
Introduceda5a923038d70d2d4a86cb4e3f32625a5ee6e7e24Fixed00d6a284fcf3fad1b7e1b5bc3cd87cbfb60ce03f
- Type
- GIT
- Repo
- https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
- Events
-
Introducedf08ccb792d3eaf1dc62d8cbf6a30d6522329f660
Affected versions
v5.*
v5.10.1
v5.10.10
v5.10.11
v5.10.12
v5.10.13
v5.10.14
v5.10.15
v5.10.16
v5.10.17
v5.10.18
v5.10.19
v5.10.2
v5.10.3
v5.10.4
v5.10.5
v5.10.6
v5.10.7
v5.10.8
v5.10.9
v5.11.1
v5.11.10
v5.11.11
v5.11.12
v5.11.13
v5.11.14
v5.11.15
v5.11.16
v5.11.17
v5.11.18
v5.11.19
v5.11.2
v5.11.20
v5.11.21
v5.11.3
v5.11.4
v5.11.5
v5.11.6
v5.11.7
v5.11.8
v5.11.9
v5.12.1
v5.12.10
v5.12.11
v5.12.12
v5.12.13
v5.12.14
v5.12.15
v5.12.16
v5.12.17
v5.12.18
v5.12.19
v5.12.2
v5.12.3
v5.12.4
v5.12.5
v5.12.6
v5.12.7
v5.12.8
v5.12.9
v5.13.1
v5.13.10
v5.13.11
v5.13.12
v5.13.13
v5.13.14
v5.13.15
v5.13.16
v5.13.17
v5.13.18
v5.13.2
v5.13.3
v5.13.4
v5.13.5
v5.13.6
v5.13.7
v5.13.8
v5.13.9
v5.14.1
v5.14.10
v5.14.11
v5.14.12
v5.14.13
v5.14.14
v5.14.15
v5.14.16
v5.14.17
v5.14.18
v5.14.19
v5.14.2
v5.14.20
v5.14.3
v5.14.4
v5.14.5
v5.14.6
v5.14.7
v5.14.8
v5.14.9
v5.15.1
v5.15.10
v5.15.100
v5.15.101
v5.15.102
v5.15.103
v5.15.104
v5.15.105
v5.15.106
v5.15.107
v5.15.108
v5.15.109
v5.15.11
v5.15.110
v5.15.111
v5.15.112
v5.15.113
v5.15.114
v5.15.115
v5.15.116
v5.15.117
v5.15.118
v5.15.119
v5.15.12
v5.15.120
v5.15.121
v5.15.122
v5.15.123
v5.15.124
v5.15.125
v5.15.126
v5.15.127
v5.15.128
v5.15.129
v5.15.13
v5.15.130
v5.15.131
v5.15.132
v5.15.133
v5.15.134
v5.15.135
v5.15.136
v5.15.137
v5.15.138
v5.15.139
v5.15.14
v5.15.140
v5.15.141
v5.15.142
v5.15.143
v5.15.144
v5.15.145
v5.15.146
v5.15.147
v5.15.148
v5.15.149
v5.15.15
v5.15.150
v5.15.16
v5.15.17
v5.15.18
v5.15.19
v5.15.2
v5.15.3
v5.15.4
v5.15.5
v5.15.6
v5.15.64
v5.15.65
v5.15.66
v5.15.67
v5.15.68
v5.15.69
v5.15.7
v5.15.70
v5.15.71
v5.15.72
v5.15.73
v5.15.74
v5.15.75
v5.15.76
v5.15.77
v5.15.78
v5.15.79
v5.15.8
v5.15.80
v5.15.81
v5.15.82
v5.15.83
v5.15.84
v5.15.85
v5.15.86
v5.15.87
v5.15.88
v5.15.89
v5.15.9
v5.15.90
v5.15.91
v5.15.92
v5.15.93
v5.15.94
v5.15.95
v5.15.96
v5.15.97
v5.15.98
v5.15.99
v5.16.1
v5.16.10
v5.16.11
v5.16.12
v5.16.13
v5.16.14
v5.16.15
v5.16.16
v5.16.17
v5.16.18
v5.16.19
v5.16.2
v5.16.20
v5.16.3
v5.16.4
v5.16.5
v5.16.6
v5.16.7
v5.16.8
v5.16.9
v5.17.1
v5.17.10
v5.17.11
v5.17.12
v5.17.13
v5.17.14
v5.17.2
v5.17.3
v5.17.4
v5.17.5
v5.17.6
v5.17.7
v5.17.8
v5.17.9
v5.18.1
v5.18.10
v5.18.11
v5.18.12
v5.18.13
v5.18.14
v5.18.15
v5.18.16
v5.18.17
v5.18.18
v5.18.19
v5.18.2
v5.18.3
v5.18.4
v5.18.5
v5.18.6
v5.18.7
v5.18.8
v5.18.9
v5.19.10
v5.19.11
v5.19.12
v5.19.13
v5.19.14
v5.19.15
v5.19.16
v5.19.17
v5.19.6
v5.19.7
v5.19.8
v5.19.9
v5.6.1
v5.6.10
v5.6.11
v5.6.12
v5.6.13
v5.6.14
v5.6.15
v5.6.16
v5.6.17
v5.6.18
v5.6.2
v5.6.3
v5.6.4
v5.6.5
v5.6.6
v5.6.7
v5.6.8
v5.6.9
v5.7.1
v5.7.10
v5.7.11
v5.7.12
v5.7.13
v5.7.14
v5.7.15
v5.7.16
v5.7.2
v5.7.3
v5.7.4
v5.7.5
v5.7.6
v5.7.7
v5.7.8
v5.7.9
v5.8.1
v5.8.10
v5.8.11
v5.8.12
v5.8.13
v5.8.14
v5.8.15
v5.8.16
v5.8.17
v5.8.18
v5.8.2
v5.8.3
v5.8.4
v5.8.5
v5.8.6
v5.8.7
v5.8.8
v5.8.9
v5.9.1
v5.9.10
v5.9.11
v5.9.12
v5.9.13
v5.9.14
v5.9.15
v5.9.16
v5.9.2
v5.9.3
v5.9.4
v5.9.5
v5.9.6
v5.9.7
v5.9.8
v5.9.9
v6.*
v6.0
v6.0-rc1
v6.0-rc2
v6.0-rc3
v6.0-rc4
v6.0-rc5
v6.0-rc6
v6.0-rc7
v6.0.1
v6.0.10
v6.0.11
v6.0.12
v6.0.13
v6.0.14
v6.0.15
v6.0.16
v6.0.17
v6.0.18
v6.0.2
v6.0.3
v6.0.4
v6.0.5
v6.0.6
v6.0.7
v6.0.8
v6.0.9
v6.1
v6.1-rc1
v6.1-rc2
v6.1-rc3
v6.1-rc4
v6.1-rc5
v6.1-rc6
v6.1-rc7
v6.1-rc8
v6.1.1
v6.1.10
v6.1.11
v6.1.12
v6.1.13
v6.1.14
v6.1.15
v6.1.16
v6.1.17
v6.1.18
v6.1.19
v6.1.2
v6.1.20
v6.1.21
v6.1.22
v6.1.23
v6.1.24
v6.1.25
v6.1.26
v6.1.27
v6.1.28
v6.1.29
v6.1.3
v6.1.30
v6.1.31
v6.1.32
v6.1.33
v6.1.34
v6.1.35
v6.1.36
v6.1.37
v6.1.38
v6.1.39
v6.1.4
v6.1.40
v6.1.41
v6.1.42
v6.1.43
v6.1.44
v6.1.45
v6.1.46
v6.1.47
v6.1.48
v6.1.49
v6.1.5
v6.1.50
v6.1.51
v6.1.52
v6.1.53
v6.1.54
v6.1.55
v6.1.56
v6.1.57
v6.1.58
v6.1.59
v6.1.6
v6.1.60
v6.1.61
v6.1.62
v6.1.63
v6.1.64
v6.1.65
v6.1.66
v6.1.67
v6.1.68
v6.1.69
v6.1.7
v6.1.70
v6.1.71
v6.1.72
v6.1.73
v6.1.74
v6.1.75
v6.1.76
v6.1.77
v6.1.78
v6.1.79
v6.1.8
v6.1.80
v6.1.9
v6.10
v6.10-rc1
v6.10-rc2
v6.10-rc3
v6.10-rc4
v6.10-rc5
v6.10-rc6
v6.10-rc7
v6.10.1
v6.10.10
v6.10.11
v6.10.12
v6.10.13
v6.10.2
v6.10.3
v6.10.4
v6.10.5
v6.10.6
v6.10.7
v6.10.8
v6.10.9
v6.11
v6.11-rc1
v6.11-rc2
v6.11-rc3
v6.11-rc4
v6.11-rc5
v6.11-rc6
v6.11-rc7
v6.11.1
v6.11.10
v6.11.11
v6.11.2
v6.11.3
v6.11.4
v6.11.5
v6.11.6
v6.11.7
v6.11.8
v6.11.9
v6.12
v6.12-rc1
v6.12-rc2
v6.12-rc3
v6.12-rc4
v6.12-rc5
v6.12-rc6
v6.12-rc7
v6.12.1
v6.12.10
v6.12.11
v6.12.12
v6.12.13
v6.12.14
v6.12.2
v6.12.3
v6.12.4
v6.12.5
v6.12.6
v6.12.7
v6.12.8
v6.12.9
v6.13
v6.13-rc1
v6.13-rc2
v6.13-rc3
v6.13-rc4
v6.13-rc5
v6.13-rc6
v6.13-rc7
v6.13.1
v6.13.10
v6.13.11
v6.13.12
v6.13.2
v6.13.3
v6.13.4
v6.13.5
v6.13.6
v6.13.7
v6.13.8
v6.13.9
v6.14
v6.14-rc1
v6.14-rc2
v6.14-rc3
v6.14-rc4
v6.14-rc5
v6.14-rc6
v6.14-rc7
v6.14.1
v6.14.10
v6.14.11
v6.14.2
v6.14.3
v6.14.4
v6.14.5
v6.14.6
v6.14.7
v6.14.8
v6.14.9
v6.15
v6.15-rc1
v6.15-rc2
v6.15-rc3
v6.15-rc4
v6.15-rc5
v6.15-rc6
v6.15-rc7
v6.15.1
v6.15.10
v6.15.11
v6.15.2
v6.15.3
v6.15.4
v6.15.5
v6.15.6
v6.15.7
v6.15.8
v6.15.9
v6.16
v6.16-rc1
v6.16-rc2
v6.16-rc3
v6.16-rc4
v6.16-rc5
v6.16-rc6
v6.16-rc7
v6.16.1
v6.16.10
v6.16.11
v6.16.2
v6.16.3
v6.16.4
v6.16.5
v6.16.6
v6.16.7
v6.16.8
v6.16.9
v6.2
v6.2-rc1
v6.2-rc2
v6.2-rc3
v6.2-rc4
v6.2-rc5
v6.2-rc6
v6.2-rc7
v6.2-rc8
v6.2.1
v6.2.10
v6.2.11
v6.2.12
v6.2.13
v6.2.14
v6.2.15
v6.2.2
v6.2.3
v6.2.4
v6.2.5
v6.2.6
v6.2.7
v6.2.8
v6.2.9
v6.3
v6.3-rc1
v6.3-rc2
v6.3-rc3
v6.3-rc4
v6.3-rc5
v6.3-rc6
v6.3-rc7
v6.3.1
v6.3.10
v6.3.11
v6.3.12
v6.3.2
v6.3.3
v6.3.4
v6.3.5
v6.3.6
v6.3.7
v6.3.8
v6.3.9
v6.4
v6.4-rc1
v6.4-rc2
v6.4-rc3
v6.4-rc4
v6.4-rc5
v6.4-rc6
v6.4-rc7
v6.4.1
v6.4.10
v6.4.11
v6.4.12
v6.4.13
v6.4.14
v6.4.15
v6.4.16
v6.4.2
v6.4.3
v6.4.4
v6.4.5
v6.4.6
v6.4.7
v6.4.8
v6.4.9
v6.5
v6.5-rc1
v6.5-rc2
v6.5-rc3
v6.5-rc4
v6.5-rc5
v6.5-rc6
v6.5-rc7
v6.5.1
v6.5.10
v6.5.11
v6.5.12
v6.5.13
v6.5.2
v6.5.3
v6.5.4
v6.5.5
v6.5.6
v6.5.7
v6.5.8
v6.5.9
v6.6
v6.6-rc1
v6.6-rc2
v6.6-rc3
v6.6-rc4
v6.6-rc5
v6.6-rc6
v6.6-rc7
v6.6.1
v6.6.10
v6.6.11
v6.6.12
v6.6.13
v6.6.14
v6.6.15
v6.6.16
v6.6.17
v6.6.18
v6.6.19
v6.6.2
v6.6.20
v6.6.3
v6.6.4
v6.6.5
v6.6.6
v6.6.7
v6.6.8
v6.6.9
v6.7
v6.7-rc1
v6.7-rc2
v6.7-rc3
v6.7-rc4
v6.7-rc5
v6.7-rc6
v6.7-rc7
v6.7-rc8
v6.7.1
v6.7.10
v6.7.11
v6.7.2
v6.7.3
v6.7.4
v6.7.5
v6.7.6
v6.7.7
v6.7.8
v6.7.9
v6.8
v6.8-rc1
v6.8-rc2
v6.8-rc3
v6.8-rc4
v6.8-rc5
v6.8-rc6
v6.8-rc7
v6.8.1
v6.8.10
v6.8.11
v6.8.2
v6.8.3
v6.8.4
v6.8.5
v6.8.6
v6.8.7
v6.8.8
v6.8.9
v6.9
v6.9-rc1
v6.9-rc2
v6.9-rc3
v6.9-rc4
v6.9-rc5
v6.9-rc6
v6.9-rc7
v6.9.1
v6.9.10
v6.9.11
v6.9.12
v6.9.2
v6.9.3
v6.9.4
v6.9.5
v6.9.6
v6.9.7
v6.9.8
v6.9.9