Overview
About vulnerability
In the Linux kernel, the following vulnerability has been resolved:
fbdev: bitblit: bound-check glyph index in bit_putcs*
bit_putcs_aligned()/unaligned() derived the glyph pointer from the character value masked by 0xff/0x1ff, which may exceed the actual font’s glyph count and read past the end of the built-in font array. Clamp the index to the actual glyph count before computing the address.
This fixes a global out-of-bounds read reported by syzbot.
Details
- Affected product:
- AlmaLinux 9.2 ESU , CentOS 7 ELS , CentOS 8.4 ELS , CentOS 8.5 ELS , CentOS Stream 8 ELS , Oracle Linux 7 ELS , RHEL 7 ELS , TuxCare 9.6 ESU , Ubuntu 20.04 ELS
- Affected packages:
- kernel-uek @ 5.4.17 (+9 more)
In the Linux kernel, the following vulnerability has been resolved:
fbdev: bitblit: bound-check glyph index in bit_putcs*
bit_putcs_aligned()/unaligned() derived the glyph pointer from the character value masked by 0xff/0x1ff, which may exceed the actual font’s glyph count and read past the end of the built-in font array. Clamp the index to the actual glyph count before computing the address.
This fixes a global out-of-bounds read reported by syzbot.