4.20-stable review patch. If anyone has any objections, please let me know.
------------------
From: Jan Kara jack@suse.cz
commit 550df5fdacff94229cde0ed9b8085155654c1696 upstream.
Push loop_ctl_mutex down to loop_set_status(). We will need this to be able to call loop_reread_partitions() without loop_ctl_mutex.
Signed-off-by: Jan Kara jack@suse.cz Signed-off-by: Jens Axboe axboe@kernel.dk Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- drivers/block/loop.c | 51 +++++++++++++++++++++++++-------------------------- 1 file changed, 25 insertions(+), 26 deletions(-)
--- a/drivers/block/loop.c +++ b/drivers/block/loop.c @@ -1141,46 +1141,55 @@ loop_set_status(struct loop_device *lo, struct loop_func_table *xfer; kuid_t uid = current_uid();
+ err = mutex_lock_killable_nested(&loop_ctl_mutex, 1); + if (err) + return err; if (lo->lo_encrypt_key_size && !uid_eq(lo->lo_key_owner, uid) && - !capable(CAP_SYS_ADMIN)) - return -EPERM; - if (lo->lo_state != Lo_bound) - return -ENXIO; - if ((unsigned int) info->lo_encrypt_key_size > LO_KEY_SIZE) - return -EINVAL; + !capable(CAP_SYS_ADMIN)) { + err = -EPERM; + goto out_unlock; + } + if (lo->lo_state != Lo_bound) { + err = -ENXIO; + goto out_unlock; + } + if ((unsigned int) info->lo_encrypt_key_size > LO_KEY_SIZE) { + err = -EINVAL; + goto out_unlock; + }
/* I/O need to be drained during transfer transition */ blk_mq_freeze_queue(lo->lo_queue);
err = loop_release_xfer(lo); if (err) - goto exit; + goto out_unfreeze;
if (info->lo_encrypt_type) { unsigned int type = info->lo_encrypt_type;
if (type >= MAX_LO_CRYPT) { err = -EINVAL; - goto exit; + goto out_unfreeze; } xfer = xfer_funcs[type]; if (xfer == NULL) { err = -EINVAL; - goto exit; + goto out_unfreeze; } } else xfer = NULL;
err = loop_init_xfer(lo, xfer, info); if (err) - goto exit; + goto out_unfreeze;
if (lo->lo_offset != info->lo_offset || lo->lo_sizelimit != info->lo_sizelimit) { if (figure_loop_size(lo, info->lo_offset, info->lo_sizelimit)) { err = -EFBIG; - goto exit; + goto out_unfreeze; } }
@@ -1212,7 +1221,7 @@ loop_set_status(struct loop_device *lo, /* update dio if lo_offset or transfer is changed */ __loop_update_dio(lo, lo->use_dio);
- exit: +out_unfreeze: blk_mq_unfreeze_queue(lo->lo_queue);
if (!err && (info->lo_flags & LO_FLAGS_PARTSCAN) && @@ -1221,6 +1230,8 @@ loop_set_status(struct loop_device *lo, lo->lo_disk->flags &= ~GENHD_FL_NO_PART_SCAN; loop_reread_partitions(lo, lo->lo_device); } +out_unlock: + mutex_unlock(&loop_ctl_mutex);
return err; } @@ -1467,12 +1478,8 @@ static int lo_ioctl(struct block_device case LOOP_SET_STATUS: err = -EPERM; if ((mode & FMODE_WRITE) || capable(CAP_SYS_ADMIN)) { - err = mutex_lock_killable_nested(&loop_ctl_mutex, 1); - if (err) - return err; err = loop_set_status_old(lo, (struct loop_info __user *)arg); - mutex_unlock(&loop_ctl_mutex); } break; case LOOP_GET_STATUS: @@ -1480,12 +1487,8 @@ static int lo_ioctl(struct block_device case LOOP_SET_STATUS64: err = -EPERM; if ((mode & FMODE_WRITE) || capable(CAP_SYS_ADMIN)) { - err = mutex_lock_killable_nested(&loop_ctl_mutex, 1); - if (err) - return err; err = loop_set_status64(lo, (struct loop_info64 __user *) arg); - mutex_unlock(&loop_ctl_mutex); } break; case LOOP_GET_STATUS64: @@ -1630,12 +1633,8 @@ static int lo_compat_ioctl(struct block_
switch(cmd) { case LOOP_SET_STATUS: - err = mutex_lock_killable(&loop_ctl_mutex); - if (!err) { - err = loop_set_status_compat(lo, - (const struct compat_loop_info __user *)arg); - mutex_unlock(&loop_ctl_mutex); - } + err = loop_set_status_compat(lo, + (const struct compat_loop_info __user *)arg); break; case LOOP_GET_STATUS: err = loop_get_status_compat(lo,