CVE-2026-89457

Summary

In the Linux kernel, the following vulnerability has been resolved:

s390/dasd: Guard sysfs discipline callbacks against unallocated private data

Several sysfs show/store handlers call a discipline callback that dereferences device->private, either directly or through the DASD_DEFINE_ATTR() macro. During dasd_generic_set_online() the discipline is assigned before check_device() allocates device->private, so an unprivileged read of one of these world-readable attributes in that window dereferences a NULL pointer and panics.

Guard the dereference inside each callback that actually touches device->private.

Affected Software

VendorProductVersion RangeStatus
LinuxLinuxc729696bcf8b23450043dd9c9972c15e53419ae4 < 644b666c202cce12ccfcf9ded67089b18f4f7659affected
LinuxLinuxc729696bcf8b23450043dd9c9972c15e53419ae4 < 4a042d8e5f34282577ece50515cea8bb1246914daffected
LinuxLinuxc729696bcf8b23450043dd9c9972c15e53419ae4 < bd8b4572528f9604a13bf3c7c2a167f5cf222f72affected
LinuxLinuxc729696bcf8b23450043dd9c9972c15e53419ae4 < 57db27ccc162afe0726cffec0ae62e410ed2d0e9affected
LinuxLinuxc729696bcf8b23450043dd9c9972c15e53419ae4 < 536407b272402af679155910d7fdeeb4834eefb9affected
LinuxLinuxc729696bcf8b23450043dd9c9972c15e53419ae4 < 6452c13646af7c13d7f6668b6690cfb2427e7f7baffected
LinuxLinuxc729696bcf8b23450043dd9c9972c15e53419ae4 < 449f3bada7a9fad8b8cdf4bb20baf27ee9ca56c5affected
LinuxLinuxc729696bcf8b23450043dd9c9972c15e53419ae4 < 2a1780f9fc2493bd34c418a0be6fc58943afcecfaffected
LinuxLinux5.3affected
LinuxLinux0 < 5.3unaffected
LinuxLinux5.10.270 <= 5.10.*unaffected
LinuxLinux5.15.221 <= 5.15.*unaffected
LinuxLinux6.1.188 <= 6.1.*unaffected
LinuxLinux6.6.157 <= 6.6.*unaffected
LinuxLinux6.12.109 <= 6.12.*unaffected
LinuxLinux6.18.50 <= 6.18.*unaffected
LinuxLinux7.2.4 <= 7.2.*unaffected
LinuxLinux7.3-rc1 <= *unaffected

Weaknesses

References