From: Zhao Mengmeng <zhaomengmeng@xxxxxxxxxx> [ Upstream commit c226964ec786f3797ed389a16392ce4357697d24 ] Refactor inode_bmap() to handle error since udf_next_aext() can return error now. On situations like ftruncate, udf_extend_file() can now detect errors and bail out early without resorting to checking for particular offsets and assuming internal behavior of these functions. Reported-by: syzbot+7a4842f0b1801230a989@xxxxxxxxxxxxxxxxxxxxxxxxx Closes: https://syzkaller.appspot.com/bug?extid=7a4842f0b1801230a989 Tested-by: syzbot+7a4842f0b1801230a989@xxxxxxxxxxxxxxxxxxxxxxxxx Signed-off-by: Zhao Mengmeng <zhaomengmeng@xxxxxxxxxx> Suggested-by: Jan Kara <jack@xxxxxxx> Signed-off-by: Jan Kara <jack@xxxxxxx> Link: https://patch.msgid.link/20241001115425.266556-4-zhaomzhao@xxxxxxx Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- fs/udf/directory.c | 13 ++++++++----- fs/udf/inode.c | 40 +++++++++++++++++++++++++--------------- fs/udf/partition.c | 6 ++++-- fs/udf/truncate.c | 6 ++++-- fs/udf/udfdecl.h | 5 +++-- 5 files changed, 44 insertions(+), 26 deletions(-) diff --git a/fs/udf/directory.c b/fs/udf/directory.c index c6950050e7aeb..632453aa38934 100644 --- a/fs/udf/directory.c +++ b/fs/udf/directory.c @@ -246,6 +246,7 @@ int udf_fiiter_init(struct udf_fileident_iter *iter, struct inode *dir, { struct udf_inode_info *iinfo = UDF_I(dir); int err = 0; + int8_t etype; iter->dir = dir; iter->bh[0] = iter->bh[1] = NULL; @@ -265,9 +266,9 @@ int udf_fiiter_init(struct udf_fileident_iter *iter, struct inode *dir, goto out; } - if (inode_bmap(dir, iter->pos >> dir->i_blkbits, &iter->epos, - &iter->eloc, &iter->elen, &iter->loffset) != - (EXT_RECORDED_ALLOCATED >> 30)) { + err = inode_bmap(dir, iter->pos >> dir->i_blkbits, &iter->epos, + &iter->eloc, &iter->elen, &iter->loffset, &etype); + if (err <= 0 || etype != (EXT_RECORDED_ALLOCATED >> 30)) { if (pos == dir->i_size) return 0; udf_err(dir->i_sb, @@ -463,6 +464,7 @@ int udf_fiiter_append_blk(struct udf_fileident_iter *iter) sector_t block; uint32_t old_elen = iter->elen; int err; + int8_t etype; if (WARN_ON_ONCE(iinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB)) return -EINVAL; @@ -477,8 +479,9 @@ int udf_fiiter_append_blk(struct udf_fileident_iter *iter) udf_fiiter_update_elen(iter, old_elen); return err; } - if (inode_bmap(iter->dir, block, &iter->epos, &iter->eloc, &iter->elen, - &iter->loffset) != (EXT_RECORDED_ALLOCATED >> 30)) { + err = inode_bmap(iter->dir, block, &iter->epos, &iter->eloc, &iter->elen, + &iter->loffset, &etype); + if (err <= 0 || etype != (EXT_RECORDED_ALLOCATED >> 30)) { udf_err(iter->dir->i_sb, "block %llu not allocated in directory (ino %lu)\n", (unsigned long long)block, iter->dir->i_ino); diff --git a/fs/udf/inode.c b/fs/udf/inode.c index 0459a87d4c02a..80dae442ecd72 100644 --- a/fs/udf/inode.c +++ b/fs/udf/inode.c @@ -406,7 +406,7 @@ struct udf_map_rq { static int udf_map_block(struct inode *inode, struct udf_map_rq *map) { - int err; + int ret; struct udf_inode_info *iinfo = UDF_I(inode); if (WARN_ON_ONCE(iinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB)) @@ -418,18 +418,24 @@ static int udf_map_block(struct inode *inode, struct udf_map_rq *map) uint32_t elen; sector_t offset; struct extent_position epos = {}; + int8_t etype; down_read(&iinfo->i_data_sem); - if (inode_bmap(inode, map->lblk, &epos, &eloc, &elen, &offset) - == (EXT_RECORDED_ALLOCATED >> 30)) { + ret = inode_bmap(inode, map->lblk, &epos, &eloc, &elen, &offset, + &etype); + if (ret < 0) + goto out_read; + if (ret > 0 && etype == (EXT_RECORDED_ALLOCATED >> 30)) { map->pblk = udf_get_lb_pblock(inode->i_sb, &eloc, offset); map->oflags |= UDF_BLK_MAPPED; + ret = 0; } +out_read: up_read(&iinfo->i_data_sem); brelse(epos.bh); - return 0; + return ret; } down_write(&iinfo->i_data_sem); @@ -440,9 +446,9 @@ static int udf_map_block(struct inode *inode, struct udf_map_rq *map) if (((loff_t)map->lblk) << inode->i_blkbits >= iinfo->i_lenExtents) udf_discard_prealloc(inode); udf_clear_extent_cache(inode); - err = inode_getblk(inode, map); + ret = inode_getblk(inode, map); up_write(&iinfo->i_data_sem); - return err; + return ret; } static int __udf_get_block(struct inode *inode, sector_t block, @@ -664,8 +670,10 @@ static int udf_extend_file(struct inode *inode, loff_t newsize) */ udf_discard_prealloc(inode); - etype = inode_bmap(inode, first_block, &epos, &eloc, &elen, &offset); - within_last_ext = (etype != -1); + err = inode_bmap(inode, first_block, &epos, &eloc, &elen, &offset, &etype); + if (err < 0) + goto out; + within_last_ext = (err == 1); /* We don't expect extents past EOF... */ WARN_ON_ONCE(within_last_ext && elen > ((loff_t)offset + 1) << inode->i_blkbits); @@ -2403,13 +2411,15 @@ int8_t udf_delete_aext(struct inode *inode, struct extent_position epos) return (elen >> 30); } -int8_t inode_bmap(struct inode *inode, sector_t block, - struct extent_position *pos, struct kernel_lb_addr *eloc, - uint32_t *elen, sector_t *offset) +/* + * Returns 1 on success, -errno on error, 0 on hit EOF. + */ +int inode_bmap(struct inode *inode, sector_t block, struct extent_position *pos, + struct kernel_lb_addr *eloc, uint32_t *elen, sector_t *offset, + int8_t *etype) { unsigned char blocksize_bits = inode->i_sb->s_blocksize_bits; loff_t lbcount = 0, bcount = (loff_t) block << blocksize_bits; - int8_t etype; struct udf_inode_info *iinfo; int err = 0; @@ -2421,13 +2431,13 @@ int8_t inode_bmap(struct inode *inode, sector_t block, } *elen = 0; do { - err = udf_next_aext(inode, pos, eloc, elen, &etype, 1); + err = udf_next_aext(inode, pos, eloc, elen, etype, 1); if (err <= 0) { if (err == 0) { *offset = (bcount - lbcount) >> blocksize_bits; iinfo->i_lenExtents = lbcount; } - return -1; + return err; } lbcount += *elen; } while (lbcount <= bcount); @@ -2435,5 +2445,5 @@ int8_t inode_bmap(struct inode *inode, sector_t block, udf_update_extent_cache(inode, lbcount - *elen, pos); *offset = (bcount + *elen - lbcount) >> blocksize_bits; - return etype; + return 1; } diff --git a/fs/udf/partition.c b/fs/udf/partition.c index af877991edc13..2b85c9501bed8 100644 --- a/fs/udf/partition.c +++ b/fs/udf/partition.c @@ -282,9 +282,11 @@ static uint32_t udf_try_read_meta(struct inode *inode, uint32_t block, sector_t ext_offset; struct extent_position epos = {}; uint32_t phyblock; + int8_t etype; + int err = 0; - if (inode_bmap(inode, block, &epos, &eloc, &elen, &ext_offset) != - (EXT_RECORDED_ALLOCATED >> 30)) + err = inode_bmap(inode, block, &epos, &eloc, &elen, &ext_offset, &etype); + if (err <= 0 || etype != (EXT_RECORDED_ALLOCATED >> 30)) phyblock = 0xFFFFFFFF; else { map = &UDF_SB(sb)->s_partmaps[partition]; diff --git a/fs/udf/truncate.c b/fs/udf/truncate.c index 399958f891d14..4f33a4a488861 100644 --- a/fs/udf/truncate.c +++ b/fs/udf/truncate.c @@ -214,10 +214,12 @@ int udf_truncate_extents(struct inode *inode) else BUG(); - etype = inode_bmap(inode, first_block, &epos, &eloc, &elen, &offset); + ret = inode_bmap(inode, first_block, &epos, &eloc, &elen, &offset, &etype); + if (ret < 0) + return ret; byte_offset = (offset << sb->s_blocksize_bits) + (inode->i_size & (sb->s_blocksize - 1)); - if (etype == -1) { + if (ret == 0) { /* We should extend the file? */ WARN_ON(byte_offset); return 0; diff --git a/fs/udf/udfdecl.h b/fs/udf/udfdecl.h index 5067ed68a8b45..d159f20d61e89 100644 --- a/fs/udf/udfdecl.h +++ b/fs/udf/udfdecl.h @@ -157,8 +157,9 @@ extern struct buffer_head *udf_bread(struct inode *inode, udf_pblk_t block, extern int udf_setsize(struct inode *, loff_t); extern void udf_evict_inode(struct inode *); extern int udf_write_inode(struct inode *, struct writeback_control *wbc); -extern int8_t inode_bmap(struct inode *, sector_t, struct extent_position *, - struct kernel_lb_addr *, uint32_t *, sector_t *); +extern int inode_bmap(struct inode *inode, sector_t block, + struct extent_position *pos, struct kernel_lb_addr *eloc, + uint32_t *elen, sector_t *offset, int8_t *etype); int udf_get_block(struct inode *, sector_t, struct buffer_head *, int); extern int udf_setup_indirect_aext(struct inode *inode, udf_pblk_t block, struct extent_position *epos); -- 2.43.0
