CVE-2026-64322

In the Linux kernel, the following vulnerability has been resolved: udf: validate sparing table length as an entry count, not a byte count udf_load_sparable_map() accepts a sparing table when sizeof(*st) + le16_to_cpu(st->reallocationTableLen) > sb->s_blocksize is false, i.e. it treats reallocationTableLen as a number of BYTES that must fit in the block. But the table is walked as an array of 8-byte sparingEntry elements: for (i = 0; i < le16_to_cpu(st->reallocationTableLen); i++) { struct sparingEntry *entry = &st->mapEntry[i]; ... entry->origLocation ... } in udf_get_pblock_spar15() and udf_relocate_blocks(). A reallocationTableLen of N therefore passes the check whenever sizeof(*st) + N <= blocksize, yet the consumers index sizeof(*st) + N * sizeof(struct sparingEntry) bytes -- up to ~8x the block. On a crafted UDF image this is an out-of-bounds read in udf_get_pblock_spar15(); udf_relocate_blocks() additionally feeds the same length to udf_update_tag(), whose crc_itu_t() reads far past the block, and its memmove() through st->mapEntry[] is an out-of-bounds write. Validate reallocationTableLen as the entry count it is, with struct_size().

• linux linux kernel (>= 2.6.32.60 < 2.6.33) • linux linux kernel (>= 2.6.34.14 < 2.6.35) • linux linux kernel (>= 3.0.37 < 3.1) • linux linux kernel (>= 3.2.23 < 3.3) • linux linux kernel (>= 3.4.5 < 3.5) • linux linux kernel (>= 3.5.1 < 5.10.261) • linux linux kernel (>= 5.11 < 5.15.212) • linux linux kernel (>= 5.16 < 6.1.178) • linux linux kernel (>= 6.2 < 6.6.145) • linux linux kernel (>= 6.7 < 6.12.96) • linux linux kernel (>= 6.13 < 6.18.39) • linux linux kernel (>= 6.19 < 7.1.4) • linux linux kernel 3.5