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| author |   Shin'ichiro Kawasaki <shinichiro.kawasaki@wdc.com> | 2021-11-09 19:47:23 +0900 |
|---|---|---|
| committer |   Jens Axboe <axboe@kernel.dk> | 2021-11-09 12:41:12 -0700 |
| commit | 35e4c6c1a2fc2eb11b9306e95cda1fa06a511948 (patch) | |
| tree | c1eccdc97dcae1924e073b8f83885e5f7e166f47 /block | |
| parent | block: Hold invalidate_lock in BLKDISCARD ioctl (diff) | |
| download | linux-dev-35e4c6c1a2fc2eb11b9306e95cda1fa06a511948.tar.xz linux-dev-35e4c6c1a2fc2eb11b9306e95cda1fa06a511948.zip | |
block: Hold invalidate_lock in BLKZEROOUT ioctl
When BLKZEROOUT ioctl and data read race, the data read leaves stale
page cache. To avoid the stale page cache, hold invalidate_lock of the
block device file mapping. The stale page cache is observed when
blktests test case block/009 is modified to call "blkdiscard -z" command
and repeated hundreds of times.
This patch can be applied back to the stable kernel version v5.15.y.
Rework is required for older stable kernels.
Fixes: 22dd6d356628 ("block: invalidate the page cache when issuing BLKZEROOUT")
Signed-off-by: Shin'ichiro Kawasaki <shinichiro.kawasaki@wdc.com>
Cc: stable@vger.kernel.org # v5.15
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20211109104723.835533-3-shinichiro.kawasaki@wdc.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Diffstat (limited to 'block')
| -rw-r--r-- | block/ioctl.c | 12 |
1 files changed, 9 insertions, 3 deletions
diff --git a/block/ioctl.c b/block/ioctl.c index 9fa87f64f703..0a1d10ac2e1a 100644 --- a/block/ioctl.c +++ b/block/ioctl.c @@ -154,6 +154,7 @@ static int blk_ioctl_zeroout(struct block_device *bdev, fmode_t mode, { uint64_t range[2]; uint64_t start, end, len; + struct inode *inode = bdev->bd_inode; int err; if (!(mode & FMODE_WRITE)) @@ -176,12 +177,17 @@ static int blk_ioctl_zeroout(struct block_device *bdev, fmode_t mode, return -EINVAL; /* Invalidate the page cache, including dirty pages */ + filemap_invalidate_lock(inode->i_mapping); err = truncate_bdev_range(bdev, mode, start, end); if (err) - return err; + goto fail; + + err = blkdev_issue_zeroout(bdev, start >> 9, len >> 9, GFP_KERNEL, + BLKDEV_ZERO_NOUNMAP); - return blkdev_issue_zeroout(bdev, start >> 9, len >> 9, GFP_KERNEL, - BLKDEV_ZERO_NOUNMAP); +fail: + filemap_invalidate_unlock(inode->i_mapping); + return err; } static int put_ushort(unsigned short __user *argp, unsigned short val) |