From: Alexey Dobriyan adobriyan@gmail.com

[ upstream commit 697ba0b6ec4ae04afb67d3911799b5e2043b4455 ]

I independently rediscovered

commit 22d24a544b0d49bbcbd61c8c0eaf77d3c9297155 block: fix overflow in blk_ioctl_discard()

but for secure erase.

Same problem:

uint64_t r[2] = {512, 18446744073709551104ULL}; ioctl(fd, BLKSECDISCARD, r);

will enter near infinite loop inside blkdev_issue_secure_erase():

a.out: attempt to access beyond end of device loop0: rw=5, sector=3399043073, nr_sectors = 1024 limit=2048 bio_check_eod: 3286214 callbacks suppressed

Signed-off-by: Alexey Dobriyan adobriyan@gmail.com Link: https://lore.kernel.org/r/9e64057f-650a-46d1-b9f7-34af391536ef@p183 Signed-off-by: Jens Axboe axboe@kernel.dk Signed-off-by: Rajani Kantha rajanikantha@engineer.com --- block/ioctl.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/block/ioctl.c b/block/ioctl.c index 378603334284..231537f79a8c 100644 --- a/block/ioctl.c +++ b/block/ioctl.c @@ -115,7 +115,7 @@ static int blk_ioctl_discard(struct block_device *bdev, blk_mode_t mode, return -EINVAL;

filemap_invalidate_lock(inode->i_mapping); - err = truncate_bdev_range(bdev, mode, start, start + len - 1); + err = truncate_bdev_range(bdev, mode, start, end - 1); if (err) goto fail; err = blkdev_issue_discard(bdev, start >> 9, len >> 9, GFP_KERNEL); @@ -127,7 +127,7 @@ static int blk_ioctl_discard(struct block_device *bdev, blk_mode_t mode, static int blk_ioctl_secure_erase(struct block_device *bdev, blk_mode_t mode, void __user *argp) { - uint64_t start, len; + uint64_t start, len, end; uint64_t range[2]; int err;

@@ -142,11 +142,12 @@ static int blk_ioctl_secure_erase(struct block_device *bdev, blk_mode_t mode, len = range[1]; if ((start & 511) || (len & 511)) return -EINVAL; - if (start + len > bdev_nr_bytes(bdev)) + if (check_add_overflow(start, len, &end) || + end > bdev_nr_bytes(bdev)) return -EINVAL;

filemap_invalidate_lock(bdev->bd_inode->i_mapping); - err = truncate_bdev_range(bdev, mode, start, start + len - 1); + err = truncate_bdev_range(bdev, mode, start, end - 1); if (!err) err = blkdev_issue_secure_erase(bdev, start >> 9, len >> 9, GFP_KERNEL); -- 2.35.3