X-Git-Url: https://git.openpandora.org/cgi-bin/gitweb.cgi?p=pandora-kernel.git;a=blobdiff_plain;f=fs%2Fudf%2Finode.c;h=5d67e2023311e3b28e9b614f213d10004155cf64;hp=4fd1d809738c519b676598f698501e7b6dc52080;hb=ef16fa90c41f032db95b7aae74e4a6ad21a283e9;hpb=e0d65113a70f1dc514e625cc4e7a7485a4bf72df diff --git a/fs/udf/inode.c b/fs/udf/inode.c index 4fd1d809738c..5d67e2023311 100644 --- a/fs/udf/inode.c +++ b/fs/udf/inode.c @@ -151,6 +151,12 @@ const struct address_space_operations udf_aops = { .bmap = udf_bmap, }; +/* + * Expand file stored in ICB to a normal one-block-file + * + * This function requires i_data_sem for writing and releases it. + * This function requires i_mutex held + */ int udf_expand_file_adinicb(struct inode *inode) { struct page *page; @@ -169,9 +175,15 @@ int udf_expand_file_adinicb(struct inode *inode) iinfo->i_alloc_type = ICBTAG_FLAG_AD_LONG; /* from now on we have normal address_space methods */ inode->i_data.a_ops = &udf_aops; + up_write(&iinfo->i_data_sem); mark_inode_dirty(inode); return 0; } + /* + * Release i_data_sem so that we can lock a page - page lock ranks + * above i_data_sem. i_mutex still protects us against file changes. + */ + up_write(&iinfo->i_data_sem); page = find_or_create_page(inode->i_mapping, 0, GFP_NOFS); if (!page) @@ -187,6 +199,7 @@ int udf_expand_file_adinicb(struct inode *inode) SetPageUptodate(page); kunmap(page); } + down_write(&iinfo->i_data_sem); memset(iinfo->i_ext.i_data + iinfo->i_lenEAttr, 0x00, iinfo->i_lenAlloc); iinfo->i_lenAlloc = 0; @@ -196,17 +209,20 @@ int udf_expand_file_adinicb(struct inode *inode) iinfo->i_alloc_type = ICBTAG_FLAG_AD_LONG; /* from now on we have normal address_space methods */ inode->i_data.a_ops = &udf_aops; + up_write(&iinfo->i_data_sem); err = inode->i_data.a_ops->writepage(page, &udf_wbc); if (err) { /* Restore everything back so that we don't lose data... */ lock_page(page); kaddr = kmap(page); + down_write(&iinfo->i_data_sem); memcpy(iinfo->i_ext.i_data + iinfo->i_lenEAttr, kaddr, inode->i_size); kunmap(page); unlock_page(page); iinfo->i_alloc_type = ICBTAG_FLAG_AD_IN_ICB; inode->i_data.a_ops = &udf_adinicb_aops; + up_write(&iinfo->i_data_sem); } page_cache_release(page); mark_inode_dirty(inode); @@ -565,6 +581,7 @@ static struct buffer_head *inode_getblk(struct inode *inode, sector_t block, struct udf_inode_info *iinfo = UDF_I(inode); int goal = 0, pgoal = iinfo->i_location.logicalBlockNum; int lastblock = 0; + bool isBeyondEOF; prev_epos.offset = udf_file_entry_alloc_offset(inode); prev_epos.block = iinfo->i_location; @@ -643,7 +660,7 @@ static struct buffer_head *inode_getblk(struct inode *inode, sector_t block, /* Are we beyond EOF? */ if (etype == -1) { int ret; - + isBeyondEOF = 1; if (count) { if (c) laarr[0] = laarr[1]; @@ -686,6 +703,7 @@ static struct buffer_head *inode_getblk(struct inode *inode, sector_t block, endnum = c + 1; lastblock = 1; } else { + isBeyondEOF = 0; endnum = startnum = ((count > 2) ? 2 : count); /* if the current extent is in position 0, @@ -728,10 +746,13 @@ static struct buffer_head *inode_getblk(struct inode *inode, sector_t block, goal, err); if (!newblocknum) { brelse(prev_epos.bh); + brelse(cur_epos.bh); + brelse(next_epos.bh); *err = -ENOSPC; return NULL; } - iinfo->i_lenExtents += inode->i_sb->s_blocksize; + if (isBeyondEOF) + iinfo->i_lenExtents += inode->i_sb->s_blocksize; } /* if the extent the requsted block is located in contains multiple @@ -758,6 +779,8 @@ static struct buffer_head *inode_getblk(struct inode *inode, sector_t block, udf_update_extents(inode, laarr, startnum, endnum, &prev_epos); brelse(prev_epos.bh); + brelse(cur_epos.bh); + brelse(next_epos.bh); newblock = udf_get_pblock(inode->i_sb, newblocknum, iinfo->i_location.partitionReferenceNum, 0); @@ -1111,10 +1134,9 @@ int udf_setsize(struct inode *inode, loff_t newsize) if (bsize < (udf_file_entry_alloc_offset(inode) + newsize)) { err = udf_expand_file_adinicb(inode); - if (err) { - up_write(&iinfo->i_data_sem); + if (err) return err; - } + down_write(&iinfo->i_data_sem); } else iinfo->i_lenAlloc = newsize; } @@ -1154,13 +1176,22 @@ update_time: return 0; } +/* + * Maximum length of linked list formed by ICB hierarchy. The chosen number is + * arbitrary - just that we hopefully don't limit any real use of rewritten + * inode on write-once media but avoid looping for too long on corrupted media. + */ +#define UDF_MAX_ICB_NESTING 1024 + static void __udf_read_inode(struct inode *inode) { struct buffer_head *bh = NULL; struct fileEntry *fe; uint16_t ident; struct udf_inode_info *iinfo = UDF_I(inode); + unsigned int indirections = 0; +reread: /* * Set defaults, but the inode is still incomplete! * Note: get_new_inode() sets the following on a new inode: @@ -1197,28 +1228,26 @@ static void __udf_read_inode(struct inode *inode) ibh = udf_read_ptagged(inode->i_sb, &iinfo->i_location, 1, &ident); if (ident == TAG_IDENT_IE && ibh) { - struct buffer_head *nbh = NULL; struct kernel_lb_addr loc; struct indirectEntry *ie; ie = (struct indirectEntry *)ibh->b_data; loc = lelb_to_cpu(ie->indirectICB.extLocation); - if (ie->indirectICB.extLength && - (nbh = udf_read_ptagged(inode->i_sb, &loc, 0, - &ident))) { - if (ident == TAG_IDENT_FE || - ident == TAG_IDENT_EFE) { - memcpy(&iinfo->i_location, - &loc, - sizeof(struct kernel_lb_addr)); - brelse(bh); - brelse(ibh); - brelse(nbh); - __udf_read_inode(inode); + if (ie->indirectICB.extLength) { + brelse(bh); + brelse(ibh); + memcpy(&iinfo->i_location, &loc, + sizeof(struct kernel_lb_addr)); + if (++indirections > UDF_MAX_ICB_NESTING) { + udf_err(inode->i_sb, + "too many ICBs in ICB hierarchy" + " (max %d supported)\n", + UDF_MAX_ICB_NESTING); + make_bad_inode(inode); return; } - brelse(nbh); + goto reread; } } brelse(ibh); @@ -1242,6 +1271,7 @@ static void udf_fill_inode(struct inode *inode, struct buffer_head *bh) struct udf_sb_info *sbi = UDF_SB(inode->i_sb); struct udf_inode_info *iinfo = UDF_I(inode); unsigned int link_count; + int bs = inode->i_sb->s_blocksize; fe = (struct fileEntry *)bh->b_data; efe = (struct extendedFileEntry *)bh->b_data; @@ -1262,41 +1292,38 @@ static void udf_fill_inode(struct inode *inode, struct buffer_head *bh) if (fe->descTag.tagIdent == cpu_to_le16(TAG_IDENT_EFE)) { iinfo->i_efe = 1; iinfo->i_use = 0; - if (udf_alloc_i_data(inode, inode->i_sb->s_blocksize - + if (udf_alloc_i_data(inode, bs - sizeof(struct extendedFileEntry))) { make_bad_inode(inode); return; } memcpy(iinfo->i_ext.i_data, bh->b_data + sizeof(struct extendedFileEntry), - inode->i_sb->s_blocksize - - sizeof(struct extendedFileEntry)); + bs - sizeof(struct extendedFileEntry)); } else if (fe->descTag.tagIdent == cpu_to_le16(TAG_IDENT_FE)) { iinfo->i_efe = 0; iinfo->i_use = 0; - if (udf_alloc_i_data(inode, inode->i_sb->s_blocksize - - sizeof(struct fileEntry))) { + if (udf_alloc_i_data(inode, bs - sizeof(struct fileEntry))) { make_bad_inode(inode); return; } memcpy(iinfo->i_ext.i_data, bh->b_data + sizeof(struct fileEntry), - inode->i_sb->s_blocksize - sizeof(struct fileEntry)); + bs - sizeof(struct fileEntry)); } else if (fe->descTag.tagIdent == cpu_to_le16(TAG_IDENT_USE)) { iinfo->i_efe = 0; iinfo->i_use = 1; iinfo->i_lenAlloc = le32_to_cpu( ((struct unallocSpaceEntry *)bh->b_data)-> lengthAllocDescs); - if (udf_alloc_i_data(inode, inode->i_sb->s_blocksize - + if (udf_alloc_i_data(inode, bs - sizeof(struct unallocSpaceEntry))) { make_bad_inode(inode); return; } memcpy(iinfo->i_ext.i_data, bh->b_data + sizeof(struct unallocSpaceEntry), - inode->i_sb->s_blocksize - - sizeof(struct unallocSpaceEntry)); + bs - sizeof(struct unallocSpaceEntry)); return; } @@ -1374,6 +1401,36 @@ static void udf_fill_inode(struct inode *inode, struct buffer_head *bh) iinfo->i_lenEAttr; } + /* + * Sanity check length of allocation descriptors and extended attrs to + * avoid integer overflows + */ + if (iinfo->i_lenEAttr > bs || iinfo->i_lenAlloc > bs) { + make_bad_inode(inode); + return; + } + /* Now do exact checks */ + if (udf_file_entry_alloc_offset(inode) + iinfo->i_lenAlloc > bs) { + make_bad_inode(inode); + return; + } + /* Sanity checks for files in ICB so that we don't get confused later */ + if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB) { + /* + * For file in ICB data is stored in allocation descriptor + * so sizes should match + */ + if (iinfo->i_lenAlloc != inode->i_size) { + make_bad_inode(inode); + return; + } + /* File in ICB has to fit in there... */ + if (inode->i_size > bs - udf_file_entry_alloc_offset(inode)) { + make_bad_inode(inode); + return; + } + } + switch (fe->icbTag.fileType) { case ICBTAG_FILE_TYPE_DIRECTORY: inode->i_op = &udf_dir_inode_operations; @@ -1918,14 +1975,29 @@ void udf_write_aext(struct inode *inode, struct extent_position *epos, epos->offset += adsize; } +/* + * Only 1 indirect extent in a row really makes sense but allow upto 16 in case + * someone does some weird stuff. + */ +#define UDF_MAX_INDIR_EXTS 16 + int8_t udf_next_aext(struct inode *inode, struct extent_position *epos, struct kernel_lb_addr *eloc, uint32_t *elen, int inc) { int8_t etype; + unsigned int indirections = 0; while ((etype = udf_current_aext(inode, epos, eloc, elen, inc)) == (EXT_NEXT_EXTENT_ALLOCDECS >> 30)) { int block; + + if (++indirections > UDF_MAX_INDIR_EXTS) { + udf_err(inode->i_sb, + "too many indirect extents in inode %lu\n", + inode->i_ino); + return -1; + } + epos->block = *eloc; epos->offset = sizeof(struct allocExtDesc); brelse(epos->bh);