kernel/linux.git/drivers/block/loop.c, branch v4.4.239

loop: Add LOOP_SET_DIRECT_IO to compat ioctl

2019-10-29T08:13:21+00:00

[ Upstream commit fdbe4eeeb1aac219b14f10c0ed31ae5d1123e9b8 ] Enabling Direct I/O with loop devices helps reducing memory usage by avoiding double caching. 32 bit applications running on 64 bits systems are currently not able to request direct I/O because is missing from the lo_compat_ioctl. This patch fixes the compatibility issue mentioned above by exporting LOOP_SET_DIRECT_IO as additional lo_compat_ioctl() entry. The input argument for this ioctl is a single long converted to a 1-bit boolean, so compatibility is preserved. Cc: Jens Axboe Signed-off-by: Alessio Balsini Signed-off-by: Jens Axboe Signed-off-by: Sasha Levin

Revert "block/loop: Use global lock for ioctl() operation."

2019-05-16T17:44:52+00:00

This reverts commit b3f3107fbd928fed6e4fecbe3da2ed5f43216439 which is commit 310ca162d779efee8a2dc3731439680f3e9c1e86 upstream. Jan Kara has reported seeing problems with this patch applied, as has Salvatore Bonaccorso, so let's drop it for now. Reported-by: Salvatore Bonaccorso Reported-by: Jan Kara Cc: Tetsuo Handa Cc: Jens Axboe Signed-off-by: Greg Kroah-Hartman

Revert "loop: Fold __loop_release into loop_release"

2019-02-06T18:43:05+00:00

This reverts commit 4ee414c3b6021db621901f2697d35774926268f6 which is commit 967d1dc144b50ad005e5eecdfadfbcfb399ffff6 upstream. It is not needed in the 4.4.y tree at this time. Reported-by: Jan Kara Cc: Jens Axboe Signed-off-by: Greg Kroah-Hartman

Revert "loop: Get rid of loop_index_mutex"

2019-02-06T18:43:05+00:00

This reverts commit 611f77199cd763e6b7c0462c2f199ddb3a089750 which is commit 0a42e99b58a208839626465af194cfe640ef9493 upstream. It is not needed in the 4.4.y tree at this time. Reported-by: Jan Kara Cc: Jens Axboe Signed-off-by: Greg Kroah-Hartman

Revert "loop: Fix double mutex_unlock(&loop_ctl_mutex) in loop_control_ioctl()"

2019-02-06T18:43:05+00:00

This reverts commit 9ec298cc874d08020f45791a8396e1593c3278c1 which is commit 628bd85947091830a8c4872adfd5ed1d515a9cf2 upstream. It is not needed in the 4.4.y tree at this point in time. Reported-by: Jan Kara Cc: Ming Lei Cc: Jan Kara Cc: Tetsuo Handa Cc: Jens Axboe Signed-off-by: Greg Kroah-Hartman

loop: Fix double mutex_unlock(&loop_ctl_mutex) in loop_control_ioctl()

2019-01-26T08:42:52+00:00

commit 628bd85947091830a8c4872adfd5ed1d515a9cf2 upstream. Commit 0a42e99b58a20883 ("loop: Get rid of loop_index_mutex") forgot to remove mutex_unlock(&loop_ctl_mutex) from loop_control_ioctl() when replacing loop_index_mutex with loop_ctl_mutex. Fixes: 0a42e99b58a20883 ("loop: Get rid of loop_index_mutex") Reported-by: syzbot Reviewed-by: Ming Lei Reviewed-by: Jan Kara Signed-off-by: Tetsuo Handa Signed-off-by: Jens Axboe Signed-off-by: Greg Kroah-Hartman

loop: Get rid of loop_index_mutex

2019-01-26T08:42:52+00:00

commit 0a42e99b58a208839626465af194cfe640ef9493 upstream. Now that loop_ctl_mutex is global, just get rid of loop_index_mutex as there is no good reason to keep these two separate and it just complicates the locking. Signed-off-by: Jan Kara Signed-off-by: Jens Axboe Signed-off-by: Greg Kroah-Hartman

loop: Fold __loop_release into loop_release

2019-01-26T08:42:51+00:00

commit 967d1dc144b50ad005e5eecdfadfbcfb399ffff6 upstream. __loop_release() has a single call site. Fold it there. This is currently not a huge win but it will make following replacement of loop_index_mutex more obvious. Signed-off-by: Jan Kara Signed-off-by: Jens Axboe Signed-off-by: Greg Kroah-Hartman

block/loop: Use global lock for ioctl() operation.

2019-01-26T08:42:51+00:00

commit 310ca162d779efee8a2dc3731439680f3e9c1e86 upstream. syzbot is reporting NULL pointer dereference [1] which is caused by race condition between ioctl(loop_fd, LOOP_CLR_FD, 0) versus ioctl(other_loop_fd, LOOP_SET_FD, loop_fd) due to traversing other loop devices at loop_validate_file() without holding corresponding lo->lo_ctl_mutex locks. Since ioctl() request on loop devices is not frequent operation, we don't need fine grained locking. Let's use global lock in order to allow safe traversal at loop_validate_file(). Note that syzbot is also reporting circular locking dependency between bdev->bd_mutex and lo->lo_ctl_mutex [2] which is caused by calling blkdev_reread_part() with lock held. This patch does not address it. [1] https://syzkaller.appspot.com/bug?id=f3cfe26e785d85f9ee259f385515291d21bd80a3 [2] https://syzkaller.appspot.com/bug?id=bf154052f0eea4bc7712499e4569505907d15889 Signed-off-by: Tetsuo Handa Reported-by: syzbot Reviewed-by: Jan Kara Signed-off-by: Jan Kara Signed-off-by: Jens Axboe Signed-off-by: Greg Kroah-Hartman

loop: remember whether sysfs_create_group() was done

2018-07-17T09:31:46+00:00

commit d3349b6b3c373ac1fbfb040b810fcee5e2adc7e0 upstream. syzbot is hitting WARN() triggered by memory allocation fault injection [1] because loop module is calling sysfs_remove_group() when sysfs_create_group() failed. Fix this by remembering whether sysfs_create_group() succeeded. [1] https://syzkaller.appspot.com/bug?id=3f86c0edf75c86d2633aeb9dd69eccc70bc7e90b Signed-off-by: Tetsuo Handa Reported-by: syzbot Reviewed-by: Greg Kroah-Hartman Renamed sysfs_ready -> sysfs_inited. Signed-off-by: Jens Axboe Signed-off-by: Greg Kroah-Hartman