udf: Make sure there's enough space for LVID implementation use field

udf_lvid_valid() verifies that the LVID has enough space for all the
tables and the reported length of ImplementationUse field. However it
doesn't make sure the reported length is large enough to contain
logicalVolIntegrityDescImpUse structure which OSTA specification
requires. This can thus lead to accesses beyond the end of LVID buffer
for suitably corrupted UDF filesystem. Add the length check.

Reported-by: Yunpeng Tian <shionthanatos@gmail.com>
Reported-by: Gongming Wang <gmwgg05@gmail.com>
Reported-by: Mingda Zhang <npczmd@qq.com>
Reported-by: Qinrun Dai <jupmouse@gmail.com>
Cc: stable@vger.kernel.org
Fixes: 781d2a9a2f ("udf: Check LVID earlier")
Signed-off-by: Jan Kara <jack@suse.cz>
This commit is contained in:
Jan Kara 2026-08-31 11:17:14 +02:00
parent cee9395acd
commit a61fb39759

View File

@ -1617,7 +1617,10 @@ static bool udf_lvid_valid(struct super_block *sb,
parts = le32_to_cpu(lvid->numOfPartitions);
impuselen = le32_to_cpu(lvid->lengthOfImpUse);
if (parts >= sb->s_blocksize || impuselen >= sb->s_blocksize ||
if (sizeof(struct logicalVolIntegrityDescImpUse) > impuselen ||
impuselen >= sb->s_blocksize)
return false;
if (parts >= sb->s_blocksize ||
sizeof(struct logicalVolIntegrityDesc) + impuselen +
2 * parts * sizeof(u32) > sb->s_blocksize)
return false;