linux/drivers/md, branch v3.4.30

dm ioctl: prevent unsafe change to dm_ioctl data_size

2013-01-17T16:50:51Z

commit e910d7ebecd1aac43125944a8641b6cb1a0dfabe upstream. Abort dm ioctl processing if userspace changes the data_size parameter after we validated it but before we finished copying the data buffer from userspace. The dm ioctl parameters are processed in the following sequence: 1. ctl_ioctl() calls copy_params(); 2. copy_params() makes a first copy of the fixed-sized portion of the userspace parameters into the local variable "tmp"; 3. copy_params() then validates tmp.data_size and allocates a new structure big enough to hold the complete data and copies the whole userspace buffer there; 4. ctl_ioctl() reads userspace data the second time and copies the whole buffer into the pointer "param"; 5. ctl_ioctl() reads param->data_size without any validation and stores it in the variable "input_param_size"; 6. "input_param_size" is further used as the authoritative size of the kernel buffer. The problem is that userspace code could change the contents of user memory between steps 2 and 4. In particular, the data_size parameter can be changed to an invalid value after the kernel has validated it. This lets userspace force the kernel to access invalid kernel memory. The fix is to ensure that the size has not changed at step 4. This patch shouldn't have a security impact because CAP_SYS_ADMIN is required to run this code, but it should be fixed anyway. Reported-by: Mikulas Patocka Signed-off-by: Alasdair G Kergon Signed-off-by: Greg Kroah-Hartman

dm persistent data: rename node to btree_node

2013-01-17T16:50:51Z

commit 550929faf89e2e2cdb3e9945ea87d383989274cf upstream. This patch fixes a compilation failure on sparc32 by renaming struct node. struct node is already defined in include/linux/node.h. On sparc32, it happens to be included through other dependencies and persistent-data doesn't compile because of conflicting declarations. Signed-off-by: Mikulas Patocka Signed-off-by: Alasdair G Kergon Signed-off-by: Greg Kroah-Hartman

md/raid10: close race that lose writes lost when replacement completes.

2012-12-10T18:59:40Z

commit e7c0c3fa29280d62aa5e11101a674bb3064bd791 upstream. When a replacement operation completes there is a small window when the original device is marked 'faulty' and the replacement still looks like a replacement. The faulty should be removed and the replacement moved in place very quickly, bit it isn't instant. So the code write out to the array must handle the possibility that the only working device for some slot in the replacement - but it doesn't. If the primary device is faulty it just gives up. This can lead to corruption. So make the code more robust: if either the primary or the replacement is present and working, write to them. Only when neither are present do we give up. This bug has been present since replacement was introduced in 3.3, so it is suitable for any -stable kernel since then. Reported-by: "George Spelvin" Signed-off-by: NeilBrown Signed-off-by: Greg Kroah-Hartman

dm: fix deadlock with request based dm and queue request_fn recursion

2012-12-03T19:47:07Z

commit a8c32a5c98943d370ea606a2e7dc04717eb92206 upstream. Request based dm attempts to re-run the request queue off the request completion path. If used with a driver that potentially does end_io from its request_fn, we could deadlock trying to recurse back into request dispatch. Fix this by punting the request queue run to kblockd. Tested to fix a quickly reproducible deadlock in such a scenario. Acked-by: Alasdair G Kergon Signed-off-by: Jens Axboe Signed-off-by: Greg Kroah-Hartman

md/raid10: decrement correct pending counter when writing to replacement.

2012-12-03T19:47:07Z

commit 884162df2aadd7414bef4935e1a54976fd4e3988 upstream. When a write to a replacement device completes, we carefully and correctly found the rdev that the write actually went to and the blithely called rdev_dec_pending on the primary rdev, even if this write was to the replacement. This means that any writes to an array while a replacement was ongoing would cause the nr_pending count for the primary device to go negative, so it could never be removed. This bug has been present since replacement was introduced in 3.3, so it is suitable for any -stable kernel since then. Reported-by: "George Spelvin" Signed-off-by: NeilBrown Signed-off-by: Greg Kroah-Hartman

md: Avoid write invalid address if read_seqretry returned true.

2012-12-03T19:47:06Z

commit 35f9ac2dcec8f79d7059ce174fd7b7ee3290d620 upstream. If read_seqretry returned true and bbp was changed, it will write invalid address which can cause some serious problem. This bug was introduced by commit v3.0-rc7-130-g2699b67. So fix is suitable for 3.0.y thru 3.6.y. Reported-by: zhuwenfeng@kedacom.com Tested-by: zhuwenfeng@kedacom.com Signed-off-by: Jianpeng Ma Signed-off-by: NeilBrown Signed-off-by: Greg Kroah-Hartman

md: Reassigned the parameters if read_seqretry returned true in func md_is_badblock.

2012-12-03T19:47:06Z

commit ab05613a0646dcc11049692d54bae76ca9ffa910 upstream. This bug was introduced by commit(v3.0-rc7-126-g2230dfe). So fix is suitable for 3.0.y thru 3.6.y. Signed-off-by: Jianpeng Ma Signed-off-by: NeilBrown Signed-off-by: Greg Kroah-Hartman

md/raid1: Fix assembling of arrays containing Replacements.

2012-11-05T08:50:41Z

commit 02b898f2f04e418094f0093a3ad0b415bcdbe8eb upstream. setup_conf in raid1.c uses conf->raid_disks before assigning a value. It is used when including 'Replacement' devices. The consequence is that assembling an array which contains a replacement will misbehave and either not include the replacement, or not include the device being replaced. Though this doesn't lead directly to data corruption, it could lead to reduced data safety. So use mddev->raid_disks, which is initialised, instead. Bug was introduced by commit c19d57980b38a5bb613a898937a1cf85f422fb9b md/raid1: recognise replacements when assembling arrays. in 3.3, so fix is suitable for 3.3.y thru 3.6.y. Signed-off-by: NeilBrown Signed-off-by: Greg Kroah-Hartman

md/raid10: use correct limit variable

2012-10-21T16:27:59Z

commit 91502f099dfc5a1e8812898e26ee280713e1d002 upstream. Clang complains that we are assigning a variable to itself. This should be using bad_sectors like the similar earlier check does. Bug has been present since 3.1-rc1. It is minor but could conceivably cause corruption or other bad behaviour. Signed-off-by: Dan Carpenter Signed-off-by: NeilBrown Signed-off-by: Greg Kroah-Hartman

dm verity: fix overflow check

2012-10-07T15:32:22Z

commit 1d55f6bcc0331d744cd5b56c4ee79e3809438161 upstream. This patch fixes sector_t overflow checking in dm-verity. Without this patch, the code checks for overflow only if sector_t is smaller than long long, not if sector_t and long long have the same size. Signed-off-by: Mikulas Patocka Signed-off-by: Alasdair G Kergon Signed-off-by: Greg Kroah-Hartman