Commit f5cc15da authored by Jan Kara's avatar Jan Kara Committed by Linus Torvalds
Browse files

Fix possible NULL pointer dereference in udf_table_free_blocks() 



Fix possible NULL pointer dereference when freeing blocks in case table of
free space is used.  Also fix handling of the case when we need to move
extent from one block to another one to make space for indirect extent.
BTW: Nobody seem to have ever used this code.

Signed-off-by: default avatarJan Kara <jack@suse.cz>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent bcec4477

fs/udf/balloc.c

+4 −6
Original line number Diff line number Diff line
@@ -540,26 +540,24 @@ static void udf_table_free_blocks(struct super_block *sb, 
			if (epos.offset + adsize > sb->s_blocksize) {

				loffset = epos.offset;

				aed->lengthAllocDescs = cpu_to_le32(adsize);

				sptr = UDF_I_DATA(inode) + epos.offset -

					udf_file_entry_alloc_offset(inode) +

					UDF_I_LENEATTR(inode) - adsize;

				sptr = UDF_I_DATA(table) + epos.offset - adsize;

				dptr = epos.bh->b_data + sizeof(struct allocExtDesc);

				memcpy(dptr, sptr, adsize);

				epos.offset = sizeof(struct allocExtDesc) + adsize;

			} else {

				loffset = epos.offset + adsize;

				aed->lengthAllocDescs = cpu_to_le32(0);

				sptr = oepos.bh->b_data + epos.offset;

				epos.offset = sizeof(struct allocExtDesc);



				if (oepos.bh) {

					sptr = oepos.bh->b_data + epos.offset;

					aed = (struct allocExtDesc *)oepos.bh->b_data;

					aed->lengthAllocDescs =

						cpu_to_le32(le32_to_cpu(aed->lengthAllocDescs) + adsize);

				} else {

					sptr = UDF_I_DATA(table) + epos.offset;

					UDF_I_LENALLOC(table) += adsize;

					mark_inode_dirty(table);

				}

				epos.offset = sizeof(struct allocExtDesc);

			}

			if (UDF_SB_UDFREV(sb) >= 0x0200)

				udf_new_tag(epos.bh->b_data, TAG_IDENT_AED, 3, 1,

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