f5b335dc025cfee90957efa90dc72fada0d5abb4 ("misc: ntsync: mark driver as "broken"
to prevent from building") was committed to avoid the driver being used while
only part of its functionality was released. Since the rest of the functionality
has now been committed, revert this.

Signed-off-by: Elizabeth Figura <zfigura@codeweavers.com>
---
 drivers/misc/Kconfig | 1 -
 1 file changed, 1 deletion(-)

diff --git a/drivers/misc/Kconfig b/drivers/misc/Kconfig
index 09cbe3f0ab1e..fb772bfe27c3 100644
--- a/drivers/misc/Kconfig
+++ b/drivers/misc/Kconfig
@@ -517,7 +517,6 @@ config OPEN_DICE
 
 config NTSYNC
 	tristate "NT synchronization primitive emulation"
-	depends on BROKEN
 	help
 	  This module provides kernel support for emulation of Windows NT
 	  synchronization primitives. It is not a hardware driver.
-- 
2.45.2

Hi Elizabeth,

kernel test robot noticed the following build errors:

[auto build test ERROR on cdd30ebb1b9f36159d66f088b61aee264e649d7a]

url:    https://github.com/intel-lab-lkp/linux/commits/Elizabeth-Figura/ntsync-Introduce-NTSYNC_IOC_WAIT_ANY/20241210-031155
base:   cdd30ebb1b9f36159d66f088b61aee264e649d7a
patch link:    https://lore.kernel.org/r/20241209185904.507350-29-zfigura%40codeweavers.com
patch subject: [PATCH v6 28/28] ntsync: No longer depend on BROKEN.
config: i386-randconfig-002-20241212 (https://download.01.org/0day-ci/archive/20241212/202412121219.EQhUbN0S-lkp@intel.com/config)
compiler: gcc-12 (Debian 12.2.0-14) 12.2.0
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20241212/202412121219.EQhUbN0S-lkp@intel.com/reproduce)

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202412121219.EQhUbN0S-lkp@intel.com/

All errors (new ones prefixed by >>):

   In file included from include/linux/spinlock.h:60,
                    from include/linux/wait.h:9,
                    from include/linux/wait_bit.h:8,
                    from include/linux/fs.h:6,
                    from drivers/misc/ntsync.c:11:
   In function 'check_copy_size',
       inlined from 'copy_from_user' at include/linux/uaccess.h:207:7,
       inlined from 'setup_wait' at drivers/misc/ntsync.c:903:6:
>> include/linux/thread_info.h:259:25: error: call to '__bad_copy_to' declared with attribute error: copy destination size is too small
     259 |                         __bad_copy_to();
         |                         ^~~~~~~~~~~~~~~


vim +/__bad_copy_to +259 include/linux/thread_info.h

b0377fedb652808 Al Viro   2017-06-29  248  
9dd819a15162f8f Kees Cook 2019-09-25  249  static __always_inline __must_check bool
b0377fedb652808 Al Viro   2017-06-29  250  check_copy_size(const void *addr, size_t bytes, bool is_source)
b0377fedb652808 Al Viro   2017-06-29  251  {
c80d92fbb67b2c8 Kees Cook 2021-06-17  252  	int sz = __builtin_object_size(addr, 0);
b0377fedb652808 Al Viro   2017-06-29  253  	if (unlikely(sz >= 0 && sz < bytes)) {
b0377fedb652808 Al Viro   2017-06-29  254  		if (!__builtin_constant_p(bytes))
b0377fedb652808 Al Viro   2017-06-29  255  			copy_overflow(sz, bytes);
b0377fedb652808 Al Viro   2017-06-29  256  		else if (is_source)
b0377fedb652808 Al Viro   2017-06-29  257  			__bad_copy_from();
b0377fedb652808 Al Viro   2017-06-29  258  		else
b0377fedb652808 Al Viro   2017-06-29 @259  			__bad_copy_to();
b0377fedb652808 Al Viro   2017-06-29  260  		return false;
b0377fedb652808 Al Viro   2017-06-29  261  	}
6d13de1489b6bf5 Kees Cook 2019-12-04  262  	if (WARN_ON_ONCE(bytes > INT_MAX))
6d13de1489b6bf5 Kees Cook 2019-12-04  263  		return false;
b0377fedb652808 Al Viro   2017-06-29  264  	check_object_size(addr, bytes, is_source);
b0377fedb652808 Al Viro   2017-06-29  265  	return true;
b0377fedb652808 Al Viro   2017-06-29  266  }
b0377fedb652808 Al Viro   2017-06-29  267  

-- 
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki

On Thu, Dec 12, 2024, at 05:52, kernel test robot wrote:
> Hi Elizabeth,
>
> kernel test robot noticed the following build errors:
>
> [auto build test ERROR on cdd30ebb1b9f36159d66f088b61aee264e649d7a]
>
> url:    
> https://github.com/intel-lab-lkp/linux/commits/Elizabeth-Figura/ntsync-Introduce-NTSYNC_IOC_WAIT_ANY/20241210-031155
> base:   cdd30ebb1b9f36159d66f088b61aee264e649d7a

> All errors (new ones prefixed by >>):
>
>    In file included from include/linux/spinlock.h:60,
>                     from include/linux/wait.h:9,
>                     from include/linux/wait_bit.h:8,
>                     from include/linux/fs.h:6,
>                     from drivers/misc/ntsync.c:11:
>    In function 'check_copy_size',
>        inlined from 'copy_from_user' at include/linux/uaccess.h:207:7,
>        inlined from 'setup_wait' at drivers/misc/ntsync.c:903:6:
>>> include/linux/thread_info.h:259:25: error: call to '__bad_copy_to' declared with attribute error: copy destination size is too small
>      259 |                         __bad_copy_to();
>          |                         ^~~~~~~~~~~~~~~

I looked up the function from the github URL above and found

	int fds[NTSYNC_MAX_WAIT_COUNT + 1];
	const __u32 count = args->count;
	struct ntsync_q *q;
	__u32 total_count;
	__u32 i, j;

	if (args->pad || (args->flags & ~NTSYNC_WAIT_REALTIME))
		return -EINVAL;

	if (args->count > NTSYNC_MAX_WAIT_COUNT)
		return -EINVAL;

	total_count = count;
	if (args->alert)
		total_count++;

	if (copy_from_user(fds, u64_to_user_ptr(args->objs),
			   array_size(count, sizeof(*fds))))
		return -EFAULT;

which looks correct to me, as it has appropriate
range checking on args->count, but I can see how
the warning may be a result of checking 'args->count'
instead of 'count'.

      Arnd