CVE-2025-38198

Description

In the Linux kernel, the following vulnerability has been resolved: fbcon: Make sure modelist not set on unregistered console It looks like attempting to write to the "store_modes" sysfs node will run afoul of unregistered consoles: UBSAN: array-index-out-of-bounds in drivers/video/fbdev/core/fbcon.c:122:28 index -1 is out of range for type 'fb_info *[32]' ... fbcon_info_from_console+0x192/0x1a0 drivers/video/fbdev/core/fbcon.c:122 fbcon_new_modelist+0xbf/0x2d0 drivers/video/fbdev/core/fbcon.c:3048 fb_new_modelist+0x328/0x440 drivers/video/fbdev/core/fbmem.c:673 store_modes+0x1c9/0x3e0 drivers/video/fbdev/core/fbsysfs.c:113 dev_attr_store+0x55/0x80 drivers/base/core.c:2439 static struct fb_info *fbcon_registered_fb[FB_MAX]; ... static signed char con2fb_map[MAX_NR_CONSOLES]; ... static struct fb_info *fbcon_info_from_console(int console) ... return fbcon_registered_fb[con2fb_map[console]]; If con2fb_map contains a -1 things go wrong here. Instead, return NULL, as callers of fbcon_info_from_console() are trying to compare against existing "info" pointers, so error handling should kick in correctly.

Affected products

Version statuses are supplied by the assigning organization. Consult the original record for detailed ranges and platform conditions.

References

• https://git.kernel.org/stable/c/b3237d451bf3a4490cb1a76f3b7c91d9888f1c4b ↗
• https://git.kernel.org/stable/c/519ba75728ee8cd561dce25fc52a2ec5c47171dc ↗
• https://git.kernel.org/stable/c/f28f1f578cd810779d01999c60618cda14c281dd ↗
• https://git.kernel.org/stable/c/54b28f7c567dd659e5f9562f518e4d7f3f6a367b ↗
• https://git.kernel.org/stable/c/cedc1b63394a866bf8663a3e40f4546f1d28c8d8 ↗
• https://lists.debian.org/debian-lts-announce/2025/10/msg00008.html ↗
• https://cert-portal.siemens.com/productcert/html/ssa-082556.html ↗