From: Jeff Moyer <jmoyer@redhat.com>
To: viro@zeniv.linux.org.uk, linux-fsdevel@vger.kernel.org
Cc: raven@themaw.net
Subject: [patch] fs: fix use after free in get_tree_bdev
Date: Mon, 10 Feb 2020 13:10:15 -0500 [thread overview]
Message-ID: <x49a75q1fg8.fsf@segfault.boston.devel.redhat.com> (raw)
Commit 6fcf0c72e4b9 ("vfs: add missing blkdev_put() in get_tree_bdev()")
introduced a use-after-free of the bdev. This was caught by fstests
generic/085, which now results in a kernel panic. Fix it.
Cc: stable@vger.kernel.org # v5.4+
Fixes: 6fcf0c72e4b9 ("vfs: add missing blkdev_put() in get_tree_bdev()")
Signed-off-by: Jeff Moyer <jmoyer@redhat.com>
diff --git a/fs/super.c b/fs/super.c
index cd352530eca9..a288cd60d2ae 100644
--- a/fs/super.c
+++ b/fs/super.c
@@ -1302,8 +1302,8 @@ int get_tree_bdev(struct fs_context *fc,
mutex_lock(&bdev->bd_fsfreeze_mutex);
if (bdev->bd_fsfreeze_count > 0) {
mutex_unlock(&bdev->bd_fsfreeze_mutex);
- blkdev_put(bdev, mode);
warnf(fc, "%pg: Can't mount, blockdev is frozen", bdev);
+ blkdev_put(bdev, mode);
return -EBUSY;
}
next reply other threads:[~2020-02-10 18:10 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-02-10 18:10 Jeff Moyer [this message]
2020-02-11 9:52 ` [patch] fs: fix use after free in get_tree_bdev Ian Kent
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