High · published June 18, 2025
In the Linux kernel, the following vulnerability has been resolved:
video: fbdev: vt8623fb: Check the size of screen before memset_io()
In the function vt8623fb_set_par(), the value of 'screen_size' is
calculated by the user input. If the user provides the improper value,
the value of 'screen_size' may larger than 'info->screen_size', which
may cause the following bug:
[ 583.339036] BUG: unable to handle page fault for address: ffffc90005000000
[ 583.339049] #PF: supervisor write access in kernel mode
[ 583.339052] #PF: error_code(0x0002) - not-present page
[ 583.339074] RIP: 0010:memset_orig+0x33/0xb0
[ 583.339110] Call Trace:
[ 583.339118] vt8623fb_set_par+0x11cd/0x21e0
[ 583.339146] fb_set_var+0x604/0xeb0
[ 583.339181] do_fb_ioctl+0x234/0x670
[ 583.339209] fb_ioctl+0xdd/0x130
Fix the this by checking the value of 'screen_size' before memset_io().
| Product | Versions | Fixed in |
|---|---|---|
| linux/linux_kernel | ≥ 2.6.22, < 4.14.291 | 4.14.291 |
| linux/linux_kernel | ≥ 4.15, < 4.19.256 | 4.19.256 |
| linux/linux_kernel | ≥ 4.20, < 5.4.211 | 5.4.211 |
| linux/linux_kernel | ≥ 5.5, < 5.10.137 | 5.10.137 |
| linux/linux_kernel | ≥ 5.11, < 5.15.61 | 5.15.61 |
| linux/linux_kernel | ≥ 5.16, < 5.18.18 | 5.18.18 |
| linux/linux_kernel | ≥ 5.19, < 5.19.2 | 5.19.2 |