lightnvm: protect target type list with correct locks

nvm_tgt_types list was protected by wrong lock for NVM_INFO ioctl call
and can race with addition or removal of target types.  Also
unregistering target type was not protected correctly.

Fixes: 5cd907853 ("lightnvm: remove nested lock conflict with mm")
Signed-off-by: Rakesh Pandit <rakesh@tuxera.com>
Reviewed-by: Javier González <javier@cnexlabs.com>
Signed-off-by: Matias Bjørling <m@bjorling.me>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This commit is contained in:
Rakesh Pandit 2017-10-13 14:45:52 +02:00 committed by Jens Axboe
parent bb6aa6f082
commit 88d31ea267

View file

@ -589,9 +589,9 @@ void nvm_unregister_tgt_type(struct nvm_tgt_type *tt)
if (!tt)
return;
down_write(&nvm_lock);
down_write(&nvm_tgtt_lock);
list_del(&tt->list);
up_write(&nvm_lock);
up_write(&nvm_tgtt_lock);
}
EXPORT_SYMBOL(nvm_unregister_tgt_type);
@ -1195,7 +1195,7 @@ static long nvm_ioctl_info(struct file *file, void __user *arg)
info->version[1] = NVM_VERSION_MINOR;
info->version[2] = NVM_VERSION_PATCH;
down_write(&nvm_lock);
down_write(&nvm_tgtt_lock);
list_for_each_entry(tt, &nvm_tgt_types, list) {
struct nvm_ioctl_info_tgt *tgt = &info->tgts[tgt_iter];
@ -1208,7 +1208,7 @@ static long nvm_ioctl_info(struct file *file, void __user *arg)
}
info->tgtsize = tgt_iter;
up_write(&nvm_lock);
up_write(&nvm_tgtt_lock);
if (copy_to_user(arg, info, sizeof(struct nvm_ioctl_info))) {
kfree(info);