CVE-2026-90333

Summary

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

dm-integrity: replace forgeable discard filler with a keyed sector marker

The discard-block check in dm_integrity_rw_tag() treats a stored tag of all 0xf6 bytes (DISCARD_FILLER) as proof a block was discarded and skips HMAC verification. allow_discards is only accepted in dm-integrity's standalone mode. An attacker with raw write access to the backing device, but without the integrity key, can stamp any block with an all-0xf6 tag and have it served as authentic.

Add a new "allow_discards_keyed" target argument that marks discarded blocks with a keyed checksum of (salt || sector) instead, computed by integrity_discard_checksum().

Affected Software

VendorProductVersion RangeStatus
LinuxLinux84597a44a9d86ac949900441cea7da0af0f2f473 < 5c58ea19a909ef6bed4f0f824e9cd7e30d7e4775affected
LinuxLinux84597a44a9d86ac949900441cea7da0af0f2f473 < 6228722c27304e4682cddc1fede03898f87e4414affected
LinuxLinux84597a44a9d86ac949900441cea7da0af0f2f473 < 68c5c42567bc462139128968ebbfadd0aefff519affected
LinuxLinux5.7affected
LinuxLinux0 < 5.7unaffected
LinuxLinux6.18.52 <= 6.18.*unaffected
LinuxLinux7.2.6 <= 7.2.*unaffected
LinuxLinux7.3-rc1 <= *unaffected

Weaknesses

References