kernel/linux.git/drivers/block, branch v4.19.16

rbd: don't return 0 on unmap if RBD_DEV_FLAG_REMOVING is set

2019-01-16T21:04:36+00:00

commit 85f5a4d666fd9be73856ed16bb36c5af5b406b29 upstream. There is a window between when RBD_DEV_FLAG_REMOVING is set and when the device is removed from rbd_dev_list. During this window, we set "already" and return 0. Returning 0 from write(2) can confuse userspace tools because 0 indicates that nothing was written. In particular, "rbd unmap" will retry the write multiple times a second: 10:28:05.463299 write(4, "0", 1) = 0 10:28:05.463509 write(4, "0", 1) = 0 10:28:05.463720 write(4, "0", 1) = 0 10:28:05.463942 write(4, "0", 1) = 0 10:28:05.464155 write(4, "0", 1) = 0 Cc: stable@vger.kernel.org Signed-off-by: Ilya Dryomov Tested-by: Dongsheng Yang Signed-off-by: Greg Kroah-Hartman

zram: fix double free backing device

2019-01-13T08:51:04+00:00

commit 5547932dc67a48713eece4fa4703bfdf0cfcb818 upstream. If blkdev_get fails, we shouldn't do blkdev_put. Otherwise, kernel emits below log. This patch fixes it. WARNING: CPU: 0 PID: 1893 at fs/block_dev.c:1828 blkdev_put+0x105/0x120 Modules linked in: CPU: 0 PID: 1893 Comm: swapoff Not tainted 4.19.0+ #453 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1 04/01/2014 RIP: 0010:blkdev_put+0x105/0x120 Call Trace: __x64_sys_swapoff+0x46d/0x490 do_syscall_64+0x5a/0x190 entry_SYSCALL_64_after_hwframe+0x49/0xbe irq event stamp: 4466 hardirqs last enabled at (4465): __free_pages_ok+0x1e3/0x490 hardirqs last disabled at (4466): trace_hardirqs_off_thunk+0x1a/0x1c softirqs last enabled at (3420): __do_softirq+0x333/0x446 softirqs last disabled at (3407): irq_exit+0xd1/0xe0 Link: http://lkml.kernel.org/r/20181127055429.251614-3-minchan@kernel.org Signed-off-by: Minchan Kim Reviewed-by: Sergey Senozhatsky Reviewed-by: Joey Pabalinas Cc: [4.14+] Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman

floppy: fix race condition in __floppy_read_block_0()

2018-12-01T08:37:32+00:00

[ Upstream commit de7b75d82f70c5469675b99ad632983c50b6f7e7 ] LKP recently reported a hang at bootup in the floppy code: [ 245.678853] INFO: task mount:580 blocked for more than 120 seconds. [ 245.679906] Tainted: G T 4.19.0-rc6-00172-ga9f38e1 #1 [ 245.680959] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [ 245.682181] mount D 6372 580 1 0x00000004 [ 245.683023] Call Trace: [ 245.683425] __schedule+0x2df/0x570 [ 245.683975] schedule+0x2d/0x80 [ 245.684476] schedule_timeout+0x19d/0x330 [ 245.685090] ? wait_for_common+0xa5/0x170 [ 245.685735] wait_for_common+0xac/0x170 [ 245.686339] ? do_sched_yield+0x90/0x90 [ 245.686935] wait_for_completion+0x12/0x20 [ 245.687571] __floppy_read_block_0+0xfb/0x150 [ 245.688244] ? floppy_resume+0x40/0x40 [ 245.688844] floppy_revalidate+0x20f/0x240 [ 245.689486] check_disk_change+0x43/0x60 [ 245.690087] floppy_open+0x1ea/0x360 [ 245.690653] __blkdev_get+0xb4/0x4d0 [ 245.691212] ? blkdev_get+0x1db/0x370 [ 245.691777] blkdev_get+0x1f3/0x370 [ 245.692351] ? path_put+0x15/0x20 [ 245.692871] ? lookup_bdev+0x4b/0x90 [ 245.693539] blkdev_get_by_path+0x3d/0x80 [ 245.694165] mount_bdev+0x2a/0x190 [ 245.694695] squashfs_mount+0x10/0x20 [ 245.695271] ? squashfs_alloc_inode+0x30/0x30 [ 245.695960] mount_fs+0xf/0x90 [ 245.696451] vfs_kern_mount+0x43/0x130 [ 245.697036] do_mount+0x187/0xc40 [ 245.697563] ? memdup_user+0x28/0x50 [ 245.698124] ksys_mount+0x60/0xc0 [ 245.698639] sys_mount+0x19/0x20 [ 245.699167] do_int80_syscall_32+0x61/0x130 [ 245.699813] entry_INT80_32+0xc7/0xc7 showing that we never complete that read request. The reason is that the completion setup is racy - it initializes the completion event AFTER submitting the IO, which means that the IO could complete before/during the init. If it does, we are passing garbage to complete() and we may sleep forever waiting for the event to occur. Fixes: 7b7b68bba5ef ("floppy: bail out in open() if drive is not responding to block0 read") Reviewed-by: Omar Sandoval Signed-off-by: Jens Axboe Signed-off-by: Sasha Levin

block: brd: associate with queue until adding disk

2018-11-27T15:12:58+00:00

[ Upstream commit 153fcd5f6d93b8e1e4040b1337f564a10f8d93af ] brd_free() may be called in failure path on one brd instance which disk isn't added yet, so release handler of gendisk may free the associated request_queue early and causes the following use-after-free[1]. This patch fixes this issue by associating gendisk with request_queue just before adding disk. [1] KASAN: use-after-free Read in del_timer_syncNon-volatile memory driver v1.3 Linux agpgart interface v0.103 [drm] Initialized vgem 1.0.0 20120112 for virtual device on minor 0 usbcore: registered new interface driver udl ================================================================== BUG: KASAN: use-after-free in __lock_acquire+0x36d9/0x4c20 kernel/locking/lockdep.c:3218 Read of size 8 at addr ffff8801d1b6b540 by task swapper/0/1 CPU: 0 PID: 1 Comm: swapper/0 Not tainted 4.19.0+ #88 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x244/0x39d lib/dump_stack.c:113 print_address_description.cold.7+0x9/0x1ff mm/kasan/report.c:256 kasan_report_error mm/kasan/report.c:354 [inline] kasan_report.cold.8+0x242/0x309 mm/kasan/report.c:412 __asan_report_load8_noabort+0x14/0x20 mm/kasan/report.c:433 __lock_acquire+0x36d9/0x4c20 kernel/locking/lockdep.c:3218 lock_acquire+0x1ed/0x520 kernel/locking/lockdep.c:3844 del_timer_sync+0xb7/0x270 kernel/time/timer.c:1283 blk_cleanup_queue+0x413/0x710 block/blk-core.c:809 brd_free+0x5d/0x71 drivers/block/brd.c:422 brd_init+0x2eb/0x393 drivers/block/brd.c:518 do_one_initcall+0x145/0x957 init/main.c:890 do_initcall_level init/main.c:958 [inline] do_initcalls init/main.c:966 [inline] do_basic_setup init/main.c:984 [inline] kernel_init_freeable+0x5c6/0x6b9 init/main.c:1148 kernel_init+0x11/0x1ae init/main.c:1068 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:350 Reported-by: syzbot+3701447012fe951dabb2@syzkaller.appspotmail.com Signed-off-by: Ming Lei Signed-off-by: Jens Axboe Signed-off-by: Sasha Levin

zram: close udev startup race condition as default groups

2018-11-21T08:19:15+00:00

commit fef912bf860e upstream. commit 98af4d4df889 upstream. I got a report from Howard Chen that he saw zram and sysfs race(ie, zram block device file is created but sysfs for it isn't yet) when he tried to create new zram devices via hotadd knob. v4.20 kernel fixes it by [1, 2] but it's too large size to merge into -stable so this patch fixes the problem by registering defualt group by Greg KH's approach[3]. This patch should be applied to every stable tree [3.16+] currently existing from kernel.org because the problem was introduced at 2.6.37 by [4]. [1] fef912bf860e, block: genhd: add 'groups' argument to device_add_disk [2] 98af4d4df889, zram: register default groups with device_add_disk() [3] http://kroah.com/log/blog/2013/06/26/how-to-create-a-sysfs-file-correctly/ [4] 33863c21e69e9, Staging: zram: Replace ioctls with sysfs interface Cc: Sergey Senozhatsky Cc: Hannes Reinecke Tested-by: Howard Chen Signed-off-by: Minchan Kim Reviewed-by: Hannes Reinecke Signed-off-by: Sasha Levin

xen-blkfront: fix kernel panic with negotiate_mq error path

2018-11-13T19:08:53+00:00

commit 6cc4a0863c9709c512280c64e698d68443ac8053 upstream. info->nr_rings isn't adjusted in case of ENOMEM error from negotiate_mq(). This leads to kernel panic in error path. Typical call stack involving panic - #8 page_fault at ffffffff8175936f [exception RIP: blkif_free_ring+33] RIP: ffffffffa0149491 RSP: ffff8804f7673c08 RFLAGS: 00010292 ... #9 blkif_free at ffffffffa0149aaa [xen_blkfront] #10 talk_to_blkback at ffffffffa014c8cd [xen_blkfront] #11 blkback_changed at ffffffffa014ea8b [xen_blkfront] #12 xenbus_otherend_changed at ffffffff81424670 #13 backend_changed at ffffffff81426dc3 #14 xenwatch_thread at ffffffff81422f29 #15 kthread at ffffffff810abe6a #16 ret_from_fork at ffffffff81754078 Cc: stable@vger.kernel.org Fixes: 7ed8ce1c5fc7 ("xen-blkfront: move negotiate_mq to cover all cases of new VBDs") Signed-off-by: Manjunath Patil Acked-by: Roger Pau Monné Signed-off-by: Juergen Gross Signed-off-by: Greg Kroah-Hartman

xen/blkfront: avoid NULL blkfront_info dereference on device removal

2018-11-13T19:08:40+00:00

commit f92898e7f32e3533bfd95be174044bc349d416ca upstream. If a block device is hot-added when we are out of grants, gnttab_grant_foreign_access fails with -ENOSPC (log message "28 granting access to ring page") in this code path: talk_to_blkback -> setup_blkring -> xenbus_grant_ring -> gnttab_grant_foreign_access and the failing path in talk_to_blkback sets the driver_data to NULL: destroy_blkring: blkif_free(info, 0); mutex_lock(&blkfront_mutex); free_info(info); mutex_unlock(&blkfront_mutex); dev_set_drvdata(&dev->dev, NULL); This results in a NULL pointer BUG when blkfront_remove and blkif_free try to access the failing device's NULL struct blkfront_info. Cc: stable@vger.kernel.org # 4.5 and later Signed-off-by: Vasilis Liaskovitis Reviewed-by: Roger Pau Monné Signed-off-by: Konrad Rzeszutek Wilk Signed-off-by: Jens Axboe Signed-off-by: Greg Kroah-Hartman

swim: fix cleanup on setup error

2018-11-13T19:08:20+00:00

[ Upstream commit 1448a2a5360ae06f25e2edc61ae070dff5c0beb4 ] If we fail to allocate the request queue for a disk, we still need to free that disk, not just the previous ones. Additionally, we need to cleanup the previous request queues. Signed-off-by: Omar Sandoval Signed-off-by: Jens Axboe Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman

ataflop: fix error handling during setup

2018-11-13T19:08:20+00:00

[ Upstream commit 71327f547ee3a46ec5c39fdbbd268401b2578d0e ] Move queue allocation next to disk allocation to fix a couple of issues: - If add_disk() hasn't been called, we should clear disk->queue before calling put_disk(). - If we fail to allocate a request queue, we still need to put all of the disks, not just the ones that we allocated queues for. Signed-off-by: Omar Sandoval Signed-off-by: Jens Axboe Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman

sunvdc: Remove VLA usage

2018-10-08T18:09:34+00:00

In the quest to remove all stack VLA usage from the kernel[1], this moves the math for cookies calculation into macros and allocates a fixed size array for the maximum number of cookies and adds a runtime sanity check. (Note that the size was always fixed, but just hidden from the compiler.) [1] https://lkml.kernel.org/r/CA+55aFzCG-zNmZwX4A2FQpadafLfEzK6CC=qPXydAacU1RqZWA@mail.gmail.com Cc: Jens Axboe Cc: linux-block@vger.kernel.org Signed-off-by: Kees Cook Signed-off-by: David S. Miller