This is a note to let you know that I've just added the patch titled
bio-integrity: Do not allocate integrity context for bio w/o data
to the 4.4-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git%3Ba=su...
The filename of the patch is: bio-integrity-do-not-allocate-integrity-context-for-bio-w-o-data.patch and it can be found in the queue-4.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree, please let stable@vger.kernel.org know about it.
From foo@baz Tue Apr 10 10:31:53 CEST 2018
From: Dmitry Monakhov dmonakhov@openvz.org Date: Wed, 10 May 2017 19:20:44 +0400 Subject: bio-integrity: Do not allocate integrity context for bio w/o data
From: Dmitry Monakhov dmonakhov@openvz.org
[ Upstream commit 3116a23bb30272d74ea81baf5d0ee23f602dd15b ]
If bio has no data, such as ones from blkdev_issue_flush(), then we have nothing to protect.
This patch prevent bugon like follows:
kfree_debugcheck: out of range ptr ac1fa1d106742a5ah kernel BUG at mm/slab.c:2773! invalid opcode: 0000 [#1] SMP Modules linked in: bcache CPU: 0 PID: 4428 Comm: xfs_io Tainted: G W 4.11.0-rc4-ext4-00041-g2ef0043-dirty #43 Hardware name: Virtuozzo KVM, BIOS seabios-1.7.5-11.vz7.4 04/01/2014 task: ffff880137786440 task.stack: ffffc90000ba8000 RIP: 0010:kfree_debugcheck+0x25/0x2a RSP: 0018:ffffc90000babde0 EFLAGS: 00010082 RAX: 0000000000000034 RBX: ac1fa1d106742a5a RCX: 0000000000000007 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff88013f3ccb40 RBP: ffffc90000babde8 R08: 0000000000000000 R09: 0000000000000000 R10: 00000000fcb76420 R11: 00000000725172ed R12: 0000000000000282 R13: ffffffff8150e766 R14: ffff88013a145e00 R15: 0000000000000001 FS: 00007fb09384bf40(0000) GS:ffff88013f200000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fd0172f9e40 CR3: 0000000137fa9000 CR4: 00000000000006f0 Call Trace: kfree+0xc8/0x1b3 bio_integrity_free+0xc3/0x16b bio_free+0x25/0x66 bio_put+0x14/0x26 blkdev_issue_flush+0x7a/0x85 blkdev_fsync+0x35/0x42 vfs_fsync_range+0x8e/0x9f vfs_fsync+0x1c/0x1e do_fsync+0x31/0x4a SyS_fsync+0x10/0x14 entry_SYSCALL_64_fastpath+0x1f/0xc2
Reviewed-by: Christoph Hellwig hch@lst.de Reviewed-by: Hannes Reinecke hare@suse.com Reviewed-by: Martin K. Petersen martin.petersen@oracle.com Signed-off-by: Dmitry Monakhov dmonakhov@openvz.org Signed-off-by: Jens Axboe axboe@fb.com Signed-off-by: Sasha Levin alexander.levin@microsoft.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- block/bio-integrity.c | 3 +++ 1 file changed, 3 insertions(+)
--- a/block/bio-integrity.c +++ b/block/bio-integrity.c @@ -175,6 +175,9 @@ bool bio_integrity_enabled(struct bio *b if (!bio_is_rw(bio)) return false;
+ if (!bio_sectors(bio)) + return false; + /* Already protected? */ if (bio_integrity(bio)) return false;
Patches currently in stable-queue which might be from dmonakhov@openvz.org are
queue-4.4/bio-integrity-do-not-allocate-integrity-context-for-bio-w-o-data.patch