kernel/linux.git/drivers/block/loop.c, branch v3.4.37

loopdev: remove an user triggerable oops

2013-03-20T20:05:01+00:00

commit b1a6650406875b9097a032eed89af50682fe1160 upstream. When loopdev is built as module and we pass an invalid parameter, loop_init() will return directly without deregister misc device, which will cause an oops when insert loop module next time because we left some garbage in the misc device list. Test case: sudo modprobe loop max_part=1024 (failed due to invalid parameter) sudo modprobe loop (oops) Clean up nicely to avoid such oops. Signed-off-by: Guo Chao Cc: Alexander Viro Cc: Guo Chao Cc: M. Hindess Cc: Nikanth Karthikesan Cc: Jens Axboe Signed-off-by: Andrew Morton Signed-off-by: Jens Axboe Acked-by: Jeff Mahoney Signed-off-by: Greg Kroah-Hartman

loopdev: fix a deadlock

2013-03-20T20:05:01+00:00

commit 5370019dc2d2c2ff90e95d181468071362934f3a upstream. bd_mutex and lo_ctl_mutex can be held in different order. Path #1: blkdev_open blkdev_get __blkdev_get (hold bd_mutex) lo_open (hold lo_ctl_mutex) Path #2: blkdev_ioctl lo_ioctl (hold lo_ctl_mutex) lo_set_capacity (hold bd_mutex) Lockdep does not report it, because path #2 actually holds a subclass of lo_ctl_mutex. This subclass seems creep into the code by mistake. The patch author actually just mentioned it in the changelog, see commit f028f3b2 ("loop: fix circular locking in loop_clr_fd()"), also see: http://marc.info/?l=linux-kernel&m=123806169129727&w=2 Path #2 hold bd_mutex to call bd_set_size(), I've protected it with i_mutex in a previous patch, so drop bd_mutex at this site. Signed-off-by: Guo Chao Cc: Alexander Viro Cc: Guo Chao Cc: M. Hindess Cc: Nikanth Karthikesan Cc: Jens Axboe Signed-off-by: Andrew Morton Signed-off-by: Jens Axboe Acked-by: Jeff Mahoney Signed-off-by: Greg Kroah-Hartman

block: remove the second argument of k[un]map_atomic()

2012-03-20T13:48:16+00:00

Signed-off-by: Cong Wang

loop: zero fill bio instead of return -EIO for partial read

2012-02-08T21:07:19+00:00

commit 8268f5a741 ("deny partial write for loop dev fd") tried to fix the loop device partial read information leak problem. But it changed the semantics of read behavior. When we read beyond the end of the device we should get 0 bytes, which is normal behavior, we should not just return -EIO Instead of returning -EIO, zero out the bio to avoid information leak in case of partail read. Signed-off-by: Dave Young Reviewed-by: Jeff Moyer Tested-by: Jeff Moyer Cc: Dmitry Monakhov Signed-off-by: Andrew Morton Signed-off-by: Jens Axboe

fs: move code out of buffer.c

2012-01-04T03:54:07+00:00

Move invalidate_bdev, block_sync_page into fs/block_dev.c. Export kill_bdev as well, so brd doesn't have to open code it. Reduce buffer_head.h requirement accordingly. Removed a rather large comment from invalidate_bdev, as it looked a bit obsolete to bother moving. The small comment replacing it says enough. Signed-off-by: Nick Piggin Cc: Al Viro Cc: Christoph Hellwig Signed-off-by: Andrew Morton Signed-off-by: Al Viro

loop: Fix discard_alignment default setting

2011-12-02T13:47:03+00:00

discard_alignment is not relevant to the loop driver since it is supposed to be set as a workaround for the old sector 63 alignments. So set it to zero rather than block size. Signed-off-by: Lukas Czerner Reported-by: Milan Broz Signed-off-by: Jens Axboe

loop: fix loop block driver discard and encryption comment

2011-11-25T08:41:25+00:00

The loop driver does not support discard if encryption is enabled, fix the comment. Signed-off-by: Dave Young Signed-off-by: Jens Axboe

loop: cleanup set_status interface

2011-11-16T08:21:49+00:00

1) Anyone who has read access to loopdev has permission to call set_status and may change important parameters such as lo_offset, lo_sizelimit and so on, which contradicts to read access pattern and definitely equals to write access pattern. 2) Add lo_offset over i_size check to prevent blkdev_size overflow. ##Testcase_bagin #dd if=/dev/zero of=./file bs=1k count=1 #losetup /dev/loop0 ./file /* userspace_application */ struct loop_info64 loinf; fd = open("/dev/loop0", O_RDONLY); ioctl(fd, LOOP_GET_STATUS64, &loinf); /* Set offset to any value which is bigger than i_size, and sizelimit * to nonzero value*/ loinf.lo_offset = 4096*1024; loinf.lo_sizelimit = 1024; ioctl(fd, LOOP_SET_STATUS64, &loinf); /* After this loop device will have size similar to 0x7fffffffffxxxx */ #blockdev --getsz /dev/loop0 ##OUTPUT: 36028797018955968 ##Testcase_end [akpm@linux-foundation.org: coding-style fixes] Signed-off-by: Dmitry Monakhov Signed-off-by: Andrew Morton Signed-off-by: Jens Axboe

loop: prevent information leak after failed read

2011-11-16T08:21:48+00:00

If read was not fully successful we have to fail whole bio to prevent information leak of old pages ##Testcase_begin dd if=/dev/zero of=./file bs=1M count=1 losetup /dev/loop0 ./file -o 4096 truncate -s 0 ./file # OOps loop offset is now beyond i_size, so read will silently fail. # So bio's pages would not be cleared, may which result in information leak. hexdump -C /dev/loop0 ##testcase_end Signed-off-by: Dmitry Monakhov Signed-off-by: Andrew Morton Signed-off-by: Jens Axboe

Merge branch 'for-3.2/drivers' of git://git.kernel.dk/linux-block

2011-11-05T00:22:14+00:00

* 'for-3.2/drivers' of git://git.kernel.dk/linux-block: (30 commits) virtio-blk: use ida to allocate disk index hpsa: add small delay when using PCI Power Management to reset for kump cciss: add small delay when using PCI Power Management to reset for kump xen/blkback: Fix two races in the handling of barrier requests. xen/blkback: Check for proper operation. xen/blkback: Fix the inhibition to map pages when discarding sector ranges. xen/blkback: Report VBD_WSECT (wr_sect) properly. xen/blkback: Support 'feature-barrier' aka old-style BARRIER requests. xen-blkfront: plug device number leak in xlblk_init() error path xen-blkfront: If no barrier or flush is supported, use invalid operation. xen-blkback: use kzalloc() in favor of kmalloc()+memset() xen-blkback: fixed indentation and comments xen-blkfront: fix a deadlock while handling discard response xen-blkfront: Handle discard requests. xen-blkback: Implement discard requests ('feature-discard') xen-blkfront: add BLKIF_OP_DISCARD and discard request struct drivers/block/loop.c: remove unnecessary bdev argument from loop_clr_fd() drivers/block/loop.c: emit uevent on auto release drivers/block/cpqarray.c: use pci_dev->revision loop: always allow userspace partitions and optionally support automatic scanning ... Fic up trivial header file includsion conflict in drivers/block/loop.c