CVE-2024-50048
- Source
- https://nvd.nist.gov/vuln/detail/CVE-2024-50048
- Import Source
- https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2024-50048.json
- JSON Data
- https://api.osv.dev/v1/vulns/CVE-2024-50048
- Downstream
- Related
- Published
- 2024-10-21T19:39:45Z
- Modified
- 2025-10-22T04:55:16.231517Z
- Summary
- fbcon: Fix a NULL pointer dereference issue in fbcon_putcs
- Details
-
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 { uint8t type; struct tioclselection 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:
setcon2fbmap -> con2fbinitdisplay -> fbconsetdisp -> redrawscreen -> hidecursor -> clearselection -> highlight -> invertscreen -> doupdateregion -> fbcon_putcs -> ops->putcs
Since ops->putcs is a NULL pointer, this leads to a kernel panic. To prevent this, we need to call setblittingtype() within setcon2fbmap() to properly initialize ops->putcs.
- References
-
- https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
- https://git.kernel.org/stable/c/5b97eebcce1b4f3f07a71f635d6aa3af96c236e7
- https://git.kernel.org/stable/c/8266ae6eafdcd5a3136592445ff4038bbc7ee80e
- https://git.kernel.org/stable/c/e5c2dba62996a3a6eeb34bd248b90fc69c5a6a1b
- https://git.kernel.org/stable/c/f7fb5dda555344529ce584ff7a28b109528d2f1b
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
-
Introducedb07db39584856e16814e2f065380e533a001535dFixed8266ae6eafdcd5a3136592445ff4038bbc7ee80e
- Type
- GIT
- Repo
- https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
- Events
-
Introducedb07db39584856e16814e2f065380e533a001535dFixedf7fb5dda555344529ce584ff7a28b109528d2f1b
- Type
- GIT
- Repo
- https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
- Events
-
Introducedb07db39584856e16814e2f065380e533a001535dFixede5c2dba62996a3a6eeb34bd248b90fc69c5a6a1b
- Type
- GIT
- Repo
- https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
- Events
-
Introducedb07db39584856e16814e2f065380e533a001535dFixed5b97eebcce1b4f3f07a71f635d6aa3af96c236e7
Affected versions
v5.*
v5.18
v5.18-rc2
v5.18-rc3
v5.18-rc4
v5.18-rc5
v5.18-rc6
v5.18-rc7
v5.19
v5.19-rc1
v5.19-rc2
v5.19-rc3
v5.19-rc4
v5.19-rc5
v5.19-rc6
v5.19-rc7
v5.19-rc8
v6.*
v6.0
v6.0-rc1
v6.0-rc2
v6.0-rc3
v6.0-rc4
v6.0-rc5
v6.0-rc6
v6.0-rc7
v6.1
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
v6.1.100
v6.1.101
v6.1.102
v6.1.103
v6.1.104
v6.1.105
v6.1.106
v6.1.107
v6.1.108
v6.1.109
v6.1.11
v6.1.110
v6.1.111
v6.1.112
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
v6.1.81
v6.1.82
v6.1.83
v6.1.84
v6.1.85
v6.1.86
v6.1.87
v6.1.88
v6.1.89
v6.1.9
v6.1.90
v6.1.91
v6.1.92
v6.1.93
v6.1.94
v6.1.95
v6.1.96
v6.1.97
v6.1.98
v6.1.99
v6.10
v6.10-rc1
v6.10-rc2
v6.10-rc3
v6.10-rc4
v6.10-rc5
v6.10-rc6
v6.10-rc7
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
v6.11.2
v6.11.3
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
v6.3
v6.3-rc1
v6.3-rc2
v6.3-rc3
v6.3-rc4
v6.3-rc5
v6.3-rc6
v6.3-rc7
v6.4
v6.4-rc1
v6.4-rc2
v6.4-rc3
v6.4-rc4
v6.4-rc5
v6.4-rc6
v6.4-rc7
v6.5
v6.5-rc1
v6.5-rc2
v6.5-rc3
v6.5-rc4
v6.5-rc5
v6.5-rc6
v6.5-rc7
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
v6.6.21
v6.6.22
v6.6.23
v6.6.24
v6.6.25
v6.6.26
v6.6.27
v6.6.28
v6.6.29
v6.6.3
v6.6.30
v6.6.31
v6.6.32
v6.6.33
v6.6.34
v6.6.35
v6.6.36
v6.6.37
v6.6.38
v6.6.39
v6.6.4
v6.6.40
v6.6.41
v6.6.42
v6.6.43
v6.6.44
v6.6.45
v6.6.46
v6.6.47
v6.6.48
v6.6.49
v6.6.5
v6.6.50
v6.6.51
v6.6.52
v6.6.53
v6.6.54
v6.6.55
v6.6.56
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
v6.8
v6.8-rc1
v6.8-rc2
v6.8-rc3
v6.8-rc4
v6.8-rc5
v6.8-rc6
v6.8-rc7
v6.9
v6.9-rc1
v6.9-rc2
v6.9-rc3
v6.9-rc4
v6.9-rc5
v6.9-rc6
v6.9-rc7