CVE-2026-93048CVE-2026-93048

In the Linux kernel, the following vulnerability has been resolved: mtd: part: reject MTDPART_OFS_RETAIN in mtd_add_partition() mtd_add_partition() does not reject the special offset value MTDPART_OFS_RETAIN (-3), which leads to a WARN_ON in add_mtd_device() when called through the BLKPG ioctl on NAND devices. The RETAIN value depends on cur_offset being the end of the previous partition, but in the dynamic partition path cur_offset equals the offset argument itself, causing undefined behavior. Commit 5daa7b21496a ("mtd: prepare partition add and del functions for ioctl requests") introduced mtd_add_partition() and correctly rejected MTDPART_OFS_APPEND (-1) and MTDPART_OFS_NXTBLK (-2), since those special offsets rely on cur_offset tracking the previous partition's end. However, commit 1a31368bf92e ("mtd: add a flags for partitions which should just leave smth. after them") later added MTDPART_OFS_RETAIN (-3) for the static partition table path without updating mtd_add_partition() t