linux-kernel - [PATCH v2] loop: unset GENHD_FL_NO_PART_SCAN on LOOP

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Date:   Mon, 10 Aug 2020 19:16:32 +0200
From:   Lennart Poettering <mzxreary@...inter.de>
To:     linux-block <linux-block@...r.kernel.org>,
        LKML <linux-kernel@...r.kernel.org>,
        Jens Axboe <axboe@...nel.dk>, Christoph Hellwig <hch@....de>,
        Yang Xu <xuyang2018.jy@...fujitsu.com>,
        Greg Kroah-Hartman <gregkh@...uxfoundation.org>
Subject: [PATCH v2] loop: unset GENHD_FL_NO_PART_SCAN on LOOP_CONFIGURE

When LOOP_CONFIGURE is used with LO_FLAGS_PARTSCAN we need to propagate
this into the GENHD_FL_NO_PART_SCAN. LOOP_SETSTATUS does this,
LOOP_CONFIGURE doesn't so far. Effect is that setting up a loopback
device with partition scanning doesn't actually work when LOOP_CONFIGURE
is issued, though it works fine with LOOP_SETSTATUS.

Let's correct that and propagate the flag in LOOP_CONFIGURE too.

Fixes: 3448914e8cc5("loop: Add LOOP_CONFIGURE ioctl")

Signed-off-by: Lennart Poettering <lennart@...ttering.net>
Acked-by: Martijn Coenen <maco@...roid.com>
---
 drivers/block/loop.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/block/loop.c b/drivers/block/loop.c
index d18160146226..2f137d6ce169 100644
--- a/drivers/block/loop.c
+++ b/drivers/block/loop.c
@@ -1171,6 +1171,8 @@ static int loop_configure(struct loop_device *lo, fmode_t mode,
 	if (part_shift)
 		lo->lo_flags |= LO_FLAGS_PARTSCAN;
 	partscan = lo->lo_flags & LO_FLAGS_PARTSCAN;
+	if (partscan)
+		lo->lo_disk->flags &= ~GENHD_FL_NO_PART_SCAN;

 	/* Grab the block_device to prevent its destruction after we
 	 * put /dev/loopXX inode. Later in __loop_clr_fd() we bdput(bdev).
--
2.26.2