kernel/git/stable/linux-stable.git/drivers/md/md.c, branch linux-2.6.32.y

md: use kzalloc() when bitmap is disabled

2015-12-05T23:49:01+00:00

commit b6878d9e03043695dbf3fa1caa6dfc09db225b16 upstream. In drivers/md/md.c get_bitmap_file() uses kmalloc() for creating a mdu_bitmap_file_t called "file". 5769 file = kmalloc(sizeof(*file), GFP_NOIO); 5770 if (!file) 5771 return -ENOMEM; This structure is copied to user space at the end of the function. 5786 if (err == 0 && 5787 copy_to_user(arg, file, sizeof(*file))) 5788 err = -EFAULT But if bitmap is disabled only the first byte of "file" is initialized with zero, so it's possible to read some bytes (up to 4095) of kernel space memory from user space. This is an information leak. 5775 /* bitmap disabled, zero the first byte and copy out */ 5776 if (!mddev->bitmap_info.file) 5777 file->pathname[0] = '\0'; Signed-off-by: Benjamin Randazzo Signed-off-by: NeilBrown [bwh: Backported to 2.6.32: patch both possible allocation calls] Signed-off-by: Ben Hutchings Signed-off-by: Willy Tarreau

md: Fix handling for devices from 2TB to 4TB in 0.90 metadata.

2011-11-07T20:31:58+00:00

commit 27a7b260f71439c40546b43588448faac01adb93 upstream. 0.90 metadata uses an unsigned 32bit number to count the number of kilobytes used from each device. This should allow up to 4TB per device. However we multiply this by 2 (to get sectors) before casting to a larger type, so sizes above 2TB get truncated. Also we allow rdev->sectors to be larger than 4TB, so it is possible for the array to be resized larger than the metadata can handle. So make sure rdev->sectors never exceeds 4TB when 0.90 metadata is in used. Also the sanity check at the end of super_90_load should include level 1 as it used ->size too. (RAID0 and Linear don't use ->size at all). Reported-by: Pim Zandbergen Signed-off-by: NeilBrown Signed-off-by: Greg Kroah-Hartman

md: avoid endless recovery loop when waiting for fail device to complete.

2011-07-13T03:29:25+00:00

commit 4274215d24633df7302069e51426659d4759c5ed upstream. If a device fails in a way that causes pending request to take a while to complete, md will not be able to immediately remove it from the array in remove_and_add_spares. It will then incorrectly look like a spare device and md will try to recover it even though it is failed. This leads to a recovery process starting and instantly aborting over and over again. We should check if the device is faulty before considering it to be a spare. This will avoid trying to start a recovery that cannot proceed. This bug was introduced in 2.6.26 so that patch is suitable for any kernel since then. Reported-by: Jim Paradis Signed-off-by: NeilBrown Signed-off-by: Greg Kroah-Hartman

md: check ->hot_remove_disk when removing disk

2011-06-23T22:24:08+00:00

commit 01393f3d5836b7d62e925e6f4658a7eb22b83a11 upstream. Check pers->hot_remove_disk instead of pers->hot_add_disk in slot_store() during disk removal. The linear personality only has ->hot_add_disk and no ->hot_remove_disk, so that removing disk in the array resulted to following kernel bug: $ sudo mdadm --create /dev/md0 --level=linear --raid-devices=4 /dev/loop[0-3] $ echo none | sudo tee /sys/block/md0/md/dev-loop2/slot BUG: unable to handle kernel NULL pointer dereference at (null) IP: [< (null)>] (null) PGD c9f5d067 PUD 8575a067 PMD 0 Oops: 0010 [#1] SMP CPU 2 Modules linked in: linear loop bridge stp llc kvm_intel kvm asus_atk0110 sr_mod cdrom sg Pid: 10450, comm: tee Not tainted 3.0.0-rc1-leonard+ #173 System manufacturer System Product Name/P5G41TD-M PRO RIP: 0010:[<0000000000000000>] [< (null)>] (null) RSP: 0018:ffff880085757df0 EFLAGS: 00010282 RAX: ffffffffa00168e0 RBX: ffff8800d1431800 RCX: 000000000000006e RDX: 0000000000000001 RSI: 0000000000000002 RDI: ffff88008543c000 RBP: ffff880085757e48 R08: 0000000000000002 R09: 000000000000000a R10: 0000000000000000 R11: ffff88008543c2e0 R12: 00000000ffffffff R13: ffff8800b4641000 R14: 0000000000000005 R15: 0000000000000000 FS: 00007fe8c9e05700(0000) GS:ffff88011fa00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b CR2: 0000000000000000 CR3: 00000000b4502000 CR4: 00000000000406e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 Process tee (pid: 10450, threadinfo ffff880085756000, task ffff8800c9f08000) Stack: ffffffff8138496a ffff8800b4641000 ffff88008543c268 0000000000000000 ffff8800b4641000 ffff88008543c000 ffff8800d1431868 ffffffff81a78a90 ffff8800b4641000 ffff88008543c000 ffff8800d1431800 ffff880085757e98 Call Trace: [] ? slot_store+0xaa/0x265 [] rdev_attr_store+0x89/0xa8 [] sysfs_write_file+0x108/0x144 [] vfs_write+0xb1/0x10d [] ? trace_hardirqs_on_caller+0x111/0x135 [] sys_write+0x4d/0x77 [] system_call_fastpath+0x16/0x1b Code: Bad RIP value. RIP [< (null)>] (null) RSP CR2: 0000000000000000 ---[ end trace ba5fc64319a826fb ]--- Signed-off-by: Namhyung Kim Signed-off-by: NeilBrown Signed-off-by: Greg Kroah-Hartman

md: correctly handle probe of an 'mdp' device.

2011-03-02T14:47:05+00:00

commit 8f5f02c460b7ca74ce55ce126ce0c1e58a3f923d upstream. 'mdp' devices are md devices with preallocated device numbers for partitions. As such it is possible to mknod and open a partition before opening the whole device. this causes md_probe() to be called with a device number of a partition, which in-turn calls mddev_find with such a number. However mddev_find expects the number of a 'whole device' and does the wrong thing with partition numbers. So add code to mddev_find to remove the 'partition' part of a device number and just work with the 'whole device'. This patch addresses https://bugzilla.kernel.org/show_bug.cgi?id=28652 Reported-by: hkmaly@bigfoot.com Signed-off-by: NeilBrown Signed-off-by: Greg Kroah-Hartman

md: fix regression with re-adding devices to arrays with no metadata

2011-02-17T23:37:09+00:00

commit bf572541ab44240163eaa2d486b06f306a31d45a upstream. Commit 1a855a0606 (2.6.37-rc4) fixed a problem where devices were re-added when they shouldn't be but caused a regression in a less common case that means sometimes devices cannot be re-added when they should be. In particular, when re-adding a device to an array without metadata we should always access the device, but after the above commit we didn't. This patch sets the In_sync flag in that case so that the re-add succeeds. This patch is suitable for any -stable kernel to which 1a855a0606 was applied. Signed-off-by: NeilBrown Signed-off-by: Greg Kroah-Hartman

block: Deprecate QUEUE_FLAG_CLUSTER and use queue_limits instead

2011-01-07T22:43:18+00:00

commit e692cb668fdd5a712c6ed2a2d6f2a36ee83997b4 upstream. When stacking devices, a request_queue is not always available. This forced us to have a no_cluster flag in the queue_limits that could be used as a carrier until the request_queue had been set up for a metadevice. There were several problems with that approach. First of all it was up to the stacking device to remember to set queue flag after stacking had completed. Also, the queue flag and the queue limits had to be kept in sync at all times. We got that wrong, which could lead to us issuing commands that went beyond the max scatterlist limit set by the driver. The proper fix is to avoid having two flags for tracking the same thing. We deprecate QUEUE_FLAG_CLUSTER and use the queue limit directly in the block layer merging functions. The queue_limit 'no_cluster' is turned into 'cluster' to avoid double negatives and to ease stacking. Clustering defaults to being enabled as before. The queue flag logic is removed from the stacking function, and explicitly setting the cluster flag is no longer necessary in DM and MD. Reported-by: Ed Lin Signed-off-by: Martin K. Petersen Acked-by: Mike Snitzer Signed-off-by: Jens Axboe Signed-off-by: Greg Kroah-Hartman

md: fix bug with re-adding of partially recovered device.

2011-01-07T22:43:09+00:00

commit 1a855a0606653d2d82506281e2c686bacb4b2f45 upstream. With v0.90 metadata, a hot-spare does not become a full member of the array until recovery is complete. So if we re-add such a device to the array, we know that all of it is as up-to-date as the event count would suggest, and so it a bitmap-based recovery is possible. However with v1.x metadata, the hot-spare immediately becomes a full member of the array, but it record how much of the device has been recovered. If the array is stopped and re-assembled recovery starts from this point. When such a device is hot-added to an array we currently lose the 'how much is recovered' information and incorrectly included it as a full in-sync member (after bitmap-based fixup). This is wrong and unsafe and could corrupt data. So be more careful about setting saved_raid_disk - which is what guides the re-adding of devices back into an array. The new code matches the code in slot_store which does a similar thing, which is encouraging. This is suitable for any -stable kernel. Reported-by: "Dailey, Nate" Signed-off-by: NeilBrown Signed-off-by: Greg Kroah-Hartman

md: fix return value of rdev_size_change()

2010-12-09T21:26:46+00:00

commit c26a44ed1e552aaa1d4ceb71842002d235fe98d7 upstream. When trying to grow an array by enlarging component devices, rdev_size_store() expects the return value of rdev_size_change() to be in sectors, but the actual value is returned in KBs. This functionality was broken by commit dd8ac336c13fd8afdb082ebacb1cddd5cf727889 so this patch is suitable for any kernel since 2.6.30. Signed-off-by: Justin Maggard Signed-off-by: NeilBrown Signed-off-by: Greg Kroah-Hartman

md: set mddev readonly flag on blkdev BLKROSET ioctl

2010-07-05T18:10:46+00:00

commit e2218350465e7e0931676b4849b594c978437bce upstream. When the user sets the block device to readwrite then the mddev should follow suit. Otherwise, the BUG_ON in md_write_start() will be set to trigger. The reverse direction, setting mddev->ro to match a set readonly request, can be ignored because the blkdev level readonly flag precludes the need to have mddev->ro set correctly. Nevermind the fact that setting mddev->ro to 1 may fail if the array is in use. Signed-off-by: Dan Williams Signed-off-by: NeilBrown Signed-off-by: Greg Kroah-Hartman