From 52c5e62d4c4beecddc6e1b8045ce1d695fca1ba7 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Wed, 14 Mar 2018 16:56:53 +0100 Subject: [PATCH] block: bio_check_eod() needs to consider partitions bio_check_eod() should check partition size not the whole disk if bio->bi_partno is non-zero. Do this by moving the call to bio_check_eod() into blk_partition_remap(). Based on an earlier patch from Jiufei Xue. Fixes: 74d46992e0d9 ("block: replace bi_bdev with a gendisk pointer and partitions index") Reported-by: Jiufei Xue Signed-off-by: Christoph Hellwig Signed-off-by: Jens Axboe --- block/blk-core.c | 93 +++++++++++++++++++++--------------------------- 1 file changed, 40 insertions(+), 53 deletions(-) diff --git a/block/blk-core.c b/block/blk-core.c index 74c6283f4509..5e88c579e896 100644 --- a/block/blk-core.c +++ b/block/blk-core.c @@ -2122,7 +2122,7 @@ out_unlock: return BLK_QC_T_NONE; } -static void handle_bad_sector(struct bio *bio) +static void handle_bad_sector(struct bio *bio, sector_t maxsector) { char b[BDEVNAME_SIZE]; @@ -2130,7 +2130,7 @@ static void handle_bad_sector(struct bio *bio) printk(KERN_INFO "%s: rw=%d, want=%Lu, limit=%Lu\n", bio_devname(bio, b), bio->bi_opf, (unsigned long long)bio_end_sector(bio), - (long long)get_capacity(bio->bi_disk)); + (long long)maxsector); } #ifdef CONFIG_FAIL_MAKE_REQUEST @@ -2191,68 +2191,59 @@ static noinline int should_fail_bio(struct bio *bio) } ALLOW_ERROR_INJECTION(should_fail_bio, ERRNO); +/* + * Check whether this bio extends beyond the end of the device or partition. + * This may well happen - the kernel calls bread() without checking the size of + * the device, e.g., when mounting a file system. + */ +static inline int bio_check_eod(struct bio *bio, sector_t maxsector) +{ + unsigned int nr_sectors = bio_sectors(bio); + + if (nr_sectors && maxsector && + (nr_sectors > maxsector || + bio->bi_iter.bi_sector > maxsector - nr_sectors)) { + handle_bad_sector(bio, maxsector); + return -EIO; + } + return 0; +} + /* * Remap block n of partition p to block n+start(p) of the disk. */ static inline int blk_partition_remap(struct bio *bio) { struct hd_struct *p; - int ret = 0; + int ret = -EIO; rcu_read_lock(); p = __disk_get_part(bio->bi_disk, bio->bi_partno); - if (unlikely(!p || should_fail_request(p, bio->bi_iter.bi_size) || - bio_check_ro(bio, p))) { - ret = -EIO; + if (unlikely(!p)) + goto out; + if (unlikely(should_fail_request(p, bio->bi_iter.bi_size))) + goto out; + if (unlikely(bio_check_ro(bio, p))) goto out; - } /* * Zone reset does not include bi_size so bio_sectors() is always 0. * Include a test for the reset op code and perform the remap if needed. */ - if (!bio_sectors(bio) && bio_op(bio) != REQ_OP_ZONE_RESET) - goto out; - - bio->bi_iter.bi_sector += p->start_sect; - bio->bi_partno = 0; - trace_block_bio_remap(bio->bi_disk->queue, bio, part_devt(p), - bio->bi_iter.bi_sector - p->start_sect); - + if (bio_sectors(bio) || bio_op(bio) == REQ_OP_ZONE_RESET) { + if (bio_check_eod(bio, part_nr_sects_read(p))) + goto out; + bio->bi_iter.bi_sector += p->start_sect; + bio->bi_partno = 0; + trace_block_bio_remap(bio->bi_disk->queue, bio, part_devt(p), + bio->bi_iter.bi_sector - p->start_sect); + } + ret = 0; out: rcu_read_unlock(); return ret; } -/* - * Check whether this bio extends beyond the end of the device. - */ -static inline int bio_check_eod(struct bio *bio, unsigned int nr_sectors) -{ - sector_t maxsector; - - if (!nr_sectors) - return 0; - - /* Test device or partition size, when known. */ - maxsector = get_capacity(bio->bi_disk); - if (maxsector) { - sector_t sector = bio->bi_iter.bi_sector; - - if (maxsector < nr_sectors || maxsector - nr_sectors < sector) { - /* - * This may well happen - the kernel calls bread() - * without checking the size of the device, e.g., when - * mounting a device. - */ - handle_bad_sector(bio); - return 1; - } - } - - return 0; -} - static noinline_for_stack bool generic_make_request_checks(struct bio *bio) { @@ -2263,9 +2254,6 @@ generic_make_request_checks(struct bio *bio) might_sleep(); - if (bio_check_eod(bio, nr_sectors)) - goto end_io; - q = bio->bi_disk->queue; if (unlikely(!q)) { printk(KERN_ERR @@ -2285,17 +2273,16 @@ generic_make_request_checks(struct bio *bio) if (should_fail_bio(bio)) goto end_io; - if (!bio->bi_partno) { - if (unlikely(bio_check_ro(bio, &bio->bi_disk->part0))) + if (bio->bi_partno) { + if (unlikely(blk_partition_remap(bio))) goto end_io; } else { - if (blk_partition_remap(bio)) + if (unlikely(bio_check_ro(bio, &bio->bi_disk->part0))) + goto end_io; + if (unlikely(bio_check_eod(bio, get_capacity(bio->bi_disk)))) goto end_io; } - if (bio_check_eod(bio, nr_sectors)) - goto end_io; - /* * Filter flush bio's early so that make_request based * drivers without flush support don't have to worry