CVE-2022-50101

Summary

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().

Affected Software

VendorProductVersion RangeStatus
LinuxLinux558b7bd86c32978648cda5deb5c758d77ef0c165 < 73280a184aa2e1a625ce54ce761042955cc79cd0affected
LinuxLinux558b7bd86c32978648cda5deb5c758d77ef0c165 < 52ad9bfeb8a0e62de30de6d39e8a49a72dd78150affected
LinuxLinux558b7bd86c32978648cda5deb5c758d77ef0c165 < d71528ccdc7ae8d7500d414091d27805c51407a2affected
LinuxLinux558b7bd86c32978648cda5deb5c758d77ef0c165 < bd8269e57621e5b38cc0b4bd2fa02e85c9f2a441affected
LinuxLinux558b7bd86c32978648cda5deb5c758d77ef0c165 < 4a3cef1eaced13ba9b55381d46bfad937a3dac2caffected
LinuxLinux558b7bd86c32978648cda5deb5c758d77ef0c165 < b17caec5127bba6f90af92bcc85871df54548ac0affected
LinuxLinux558b7bd86c32978648cda5deb5c758d77ef0c165 < c7a3f41e4b133d4dd25bc996b69039b19a34d69daffected
LinuxLinux558b7bd86c32978648cda5deb5c758d77ef0c165 < ec0754c60217248fa77cc9005d66b2b55200ac06affected
LinuxLinux2.6.22affected
LinuxLinux0 < 2.6.22unaffected
LinuxLinux4.14.291 <= 4.14.*unaffected
LinuxLinux4.19.256 <= 4.19.*unaffected
LinuxLinux5.4.211 <= 5.4.*unaffected
LinuxLinux5.10.137 <= 5.10.*unaffected
LinuxLinux5.15.61 <= 5.15.*unaffected
LinuxLinux5.18.18 <= 5.18.*unaffected
LinuxLinux5.19.2 <= 5.19.*unaffected
LinuxLinux6.0 <= *unaffected

Weaknesses

References