Rasmus Villemoes e186b19bc3
include/linux/bitops.h: sanitize rotate primitives ...
commit ef4d6f6b275c498f8e5626c99dbeefdc5027f843 upstream.
The ror32 implementation (word >> shift) | (word << (32 - shift) has
undefined behaviour if shift is outside the [1, 31] range. Similarly
for the 64 bit variants. Most callers pass a compile-time constant
(naturally in that range), but there's an UBSAN report that these may
actually be called with a shift count of 0.
Instead of special-casing that, we can make them DTRT for all values of
shift while also avoiding UB. For some reason, this was already partly
done for rol32 (which was well-defined for [0, 31]). gcc 8 recognizes
these patterns as rotates, so for example
__u32 rol32(__u32 word, unsigned int shift)
{
return (word << (shift & 31)) | (word >> ((-shift) & 31));
}
compiles to
0000000000000020 <rol32>:
20: 89 f8 mov %edi,%eax
22: 89 f1 mov %esi,%ecx
24: d3 c0 rol %cl,%eax
26: c3 retq
Older compilers unfortunately do not do as well, but this only affects
the small minority of users that don't pass constants.
Due to integer promotions, ro[lr]8 were already well-defined for shifts
in [0, 8], and ro[lr]16 were mostly well-defined for shifts in [0, 16]
(only mostly - u16 gets promoted to _signed_ int, so if bit 15 is set,
word << 16 is undefined). For consistency, update those as well.
Link: http://lkml.kernel.org/r/20190410211906.2190-1-linux@rasmusvillemoes.dk
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk >
Reported-by: Ido Schimmel <idosch@mellanox.com >
Tested-by: Ido Schimmel <idosch@mellanox.com >
Reviewed-by: Will Deacon <will.deacon@arm.com >
Cc: Vadim Pasternak <vadimp@mellanox.com >
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com >
Cc: Jacek Anaszewski <jacek.anaszewski@gmail.com >
Cc: Pavel Machek <pavel@ucw.cz >
Signed-off-by: Andrew Morton <akpm@linux-foundation.org >
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org >
Signed-off-by: Matthias Kaehlcke <mka@chromium.org >
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org >
2019-06-11 12:22:36 +02:00
2016-10-12 11:01:37 -07:00
2016-10-05 10:11:24 -07:00
2018-12-01 09:44:19 +01:00
2019-03-27 14:13:02 +09:00
2016-09-15 21:15:40 +05:30
2016-09-10 16:48:46 +05:30
2016-09-01 14:23:39 -07:00
2018-08-24 13:12:40 +02:00
2016-10-11 15:06:33 -07:00
2019-05-31 06:48:27 -07:00
2016-10-17 16:26:29 +01:00
2017-03-15 10:02:46 +08:00
2016-07-28 09:34:47 +05:30
2019-05-21 18:48:58 +02:00
2018-04-13 19:48:19 +02:00
2019-04-17 08:36:45 +02:00
2018-08-03 07:55:22 +02:00
2018-05-01 15:13:07 -07:00
2018-11-27 16:09:39 +01:00
2018-10-13 09:18:58 +02:00
2016-10-03 19:43:08 -07:00
2016-11-05 13:45:02 +05:30
2018-10-03 17:01:52 -07:00
2017-01-19 20:18:07 +01:00
2016-10-22 17:08:07 -04:00
2016-10-07 09:45:43 -07:00
2018-03-22 09:17:44 +01:00
2019-05-14 19:19:36 +02:00
2016-08-23 15:46:33 -05:00
2016-09-30 09:14:10 -07:00
2019-01-16 22:12:33 +01:00
2016-09-14 20:37:50 +02:00
2018-05-25 16:13:04 +02:00
2016-09-12 20:32:40 +01:00
2017-12-20 10:07:26 +01:00
2016-09-20 14:35:59 -05:00
2016-09-05 12:41:46 +02:00
2018-10-03 17:01:54 -07:00
2016-08-25 11:26:48 -04:00
2019-04-20 09:07:54 +02:00
2016-09-27 12:54:03 +02:00
2017-10-08 10:26:06 +02:00
2016-10-11 15:06:31 -07:00
2016-10-11 15:06:31 -07:00
2019-05-21 18:49:01 +02:00
2018-04-24 09:34:18 +02:00
2019-05-31 06:48:11 -07:00
2016-09-09 12:09:24 +03:00
2016-08-18 10:44:20 +02:00
2019-06-11 12:22:36 +02:00
2019-04-17 08:36:46 +02:00
2019-05-14 19:19:34 +02:00
2016-09-14 09:18:06 -06:00
2016-10-14 12:18:50 -07:00
2016-09-15 08:42:03 -06:00
2016-10-09 17:32:20 -07:00
2018-07-03 11:23:18 +02:00
2016-09-15 18:29:06 -04:00
2016-10-07 18:46:28 -07:00
2018-12-08 13:05:10 +01:00
2018-01-31 12:55:57 +01:00
2017-12-09 22:01:54 +01:00
2016-09-09 12:09:24 +03:00
2016-08-11 09:41:35 -06:00
2018-01-31 12:55:51 +01:00
2017-01-06 10:40:13 +01:00
2017-09-27 14:39:20 +02:00
2016-08-22 14:05:49 -03:00
2016-08-22 14:00:51 -03:00
2018-03-31 18:11:33 +02:00
2017-06-14 15:06:00 +02:00
2016-10-17 15:27:27 -07:00
2016-07-30 11:20:02 -07:00
2019-02-27 10:07:01 +01:00
2016-10-07 18:46:29 -07:00
2018-12-21 14:11:29 +01:00
2019-01-31 08:12:35 +01:00
2019-01-31 08:12:35 +01:00
2019-01-31 08:12:35 +01:00
2018-07-03 11:23:07 +02:00
2016-11-11 08:12:37 -08:00
2016-08-02 16:11:27 -04:00
2017-07-05 14:40:26 +02:00
2016-08-31 13:05:43 +02:00
2019-05-14 19:19:41 +02:00
2019-03-13 14:04:51 -07:00
2018-01-02 20:35:17 +01:00
2018-05-30 07:50:26 +02:00
2017-10-12 11:51:25 +02:00
2018-01-10 09:29:52 +01:00
2018-09-26 08:36:37 +02:00
2016-10-11 15:06:30 -07:00
2018-02-28 10:18:33 +01:00
2018-05-30 07:50:16 +02:00
2017-03-22 12:43:33 +01:00
2017-03-15 10:02:44 +08:00
2016-09-06 13:08:40 +09:00
2017-03-12 06:41:44 +01:00
2019-03-23 13:19:52 +01:00
2017-07-15 12:16:11 +02:00
2016-09-26 22:16:41 +05:30
2018-08-03 07:55:22 +02:00
2017-12-14 09:28:11 +01:00
2016-08-08 08:11:42 +05:30
2016-08-04 08:50:07 -04:00
2019-05-16 19:43:42 +02:00
2018-11-10 07:42:48 -08:00
2016-10-14 14:26:58 -07:00
2016-10-06 09:07:44 -04:00
2016-08-04 10:16:56 +09:30
2016-09-16 08:53:41 +02:00
2017-05-14 14:00:22 +02:00
2016-10-03 09:11:14 -07:00
2017-07-12 15:01:02 +02:00
2018-02-13 12:36:00 +01:00
2016-08-11 15:33:23 +05:30
2017-12-09 22:01:56 +01:00
2016-09-09 19:36:04 -07:00
2016-08-02 19:35:10 -04:00
2018-01-17 09:38:58 +01:00
2016-11-11 08:12:37 -08:00
2018-12-01 09:44:25 +01:00
2017-06-17 06:41:52 +02:00
2018-01-10 09:29:52 +01:00
2017-03-31 10:31:46 +02:00
2018-03-28 18:39:23 +02:00
2016-10-07 18:46:26 -07:00
2017-08-06 18:59:43 -07:00
2016-09-02 12:47:55 -04:00
2016-10-06 11:48:41 -07:00
2017-12-14 09:28:22 +01:00
2017-05-14 14:00:22 +02:00
2019-02-12 19:44:56 +01:00
2016-07-28 16:07:41 -07:00
2019-02-15 08:07:39 +01:00
2017-05-25 15:44:41 +02:00
2019-05-31 06:48:29 -07:00
2016-08-24 15:58:57 +02:00
2018-10-20 09:51:31 +02:00
2019-05-31 06:48:12 -07:00
2016-08-24 21:04:48 +08:00
2016-09-08 21:34:15 -07:00
2017-10-27 10:38:08 +02:00
2016-09-05 13:52:38 +02:00
2016-08-25 22:11:02 +02:00
2016-09-24 10:48:18 +02:00
2016-07-27 14:20:09 -07:00
2018-11-21 09:26:01 +01:00
2016-09-01 22:48:33 -07:00
2016-09-24 08:01:26 -04:00
2016-10-07 23:50:39 -04:00
2018-04-29 11:32:01 +02:00
2016-09-08 16:13:09 -07:00
2016-09-16 09:18:54 +02:00
2018-04-08 12:12:52 +02:00
2018-12-01 09:44:26 +01:00
2018-09-09 20:01:24 +02:00
2016-09-14 22:11:09 +02:00
2016-08-24 09:43:49 +02:00
2016-10-26 15:45:38 +10:00
2016-10-20 15:51:28 +11:00
2016-09-16 09:34:15 +01:00
2016-09-14 09:18:09 -06:00
2016-08-08 14:42:03 -05:00
2016-07-27 10:24:38 -05:00
2018-01-02 20:35:11 +01:00
2017-02-09 08:08:31 +01:00
2019-04-05 22:29:12 +02:00
2018-02-22 15:43:48 +01:00
2018-10-10 08:53:18 +02:00
2017-01-19 20:17:59 +01:00
2016-10-03 13:22:39 -07:00
2018-02-22 15:43:55 +01:00
2019-05-08 07:19:07 +02:00
2018-11-23 08:20:35 +01:00
2016-10-27 18:43:43 -07:00
2018-05-30 07:50:26 +02:00
2016-07-28 16:07:41 -07:00
2016-10-09 12:23:38 -07:00
2019-05-10 17:52:09 +02:00
2016-08-10 11:23:44 -04:00
2016-10-11 15:06:33 -07:00
2017-10-27 10:38:11 +02:00
2016-10-11 15:06:33 -07:00
2019-02-06 17:33:29 +01:00
2019-04-27 09:34:44 +02:00
2016-10-11 15:06:33 -07:00
2016-10-05 10:11:24 -07:00
2018-05-30 07:50:30 +02:00
2016-09-15 16:49:39 +02:00
2018-07-17 11:37:52 +02:00
2017-03-15 10:02:47 +08:00
2016-09-21 07:57:31 -06:00
2017-07-21 07:42:21 +02:00
2019-05-16 19:43:40 +02:00
2019-05-21 18:48:55 +02:00
2016-08-18 23:41:55 +02:00
2018-04-08 12:12:50 +02:00
2016-09-24 10:48:32 +02:00
2017-06-17 06:41:51 +02:00
2016-09-19 13:42:38 -04:00
2016-09-19 12:27:10 +10:00
2017-10-27 10:38:08 +02:00
2016-09-27 12:33:47 +02:00
2017-08-24 17:12:19 -07:00
2017-04-08 09:30:35 +02:00
2017-02-09 08:08:28 +01:00
2016-09-01 17:52:01 -07:00
2016-07-28 16:07:41 -07:00
2017-06-17 06:41:54 +02:00
2016-08-31 14:12:35 +02:00
2017-01-19 20:17:59 +01:00
2018-09-19 22:47:17 +02:00
2019-05-10 17:52:09 +02:00
2017-12-20 10:07:29 +01:00
2017-12-14 09:28:16 +01:00
2018-01-31 12:55:53 +01:00
2018-11-23 08:20:35 +01:00
2017-03-15 10:02:44 +08:00
2016-09-25 23:41:39 -04:00
2016-09-25 23:41:39 -04:00
2019-01-09 16:16:43 +01:00
2016-07-29 12:17:52 -07:00
2016-10-07 09:20:53 -07:00
2016-08-28 23:32:41 -04:00
2019-02-23 09:05:58 +01:00
2019-02-06 17:33:27 +01:00
2016-09-25 14:38:48 +02:00
2016-09-25 23:34:19 +02:00
2017-02-01 08:33:08 +01:00
2016-09-22 15:54:27 -04:00
2017-08-11 08:49:28 -07:00
2017-06-17 06:41:57 +02:00
2018-05-22 16:58:02 +02:00
2016-10-19 11:36:22 -06:00
2016-09-28 17:43:15 +02:00
2016-10-03 23:38:11 +02:00
2016-11-29 23:17:02 -05:00
2016-09-16 09:34:14 +01:00
2019-05-25 18:26:47 +02:00
2016-09-28 08:53:14 +05:30
2017-12-14 09:28:16 +01:00
2016-10-07 18:46:28 -07:00
2019-01-31 08:12:35 +01:00
2016-09-19 21:44:30 +02:00
2016-10-07 18:46:27 -07:00
2016-10-07 18:46:27 -07:00
2018-03-22 09:17:44 +01:00
2018-09-15 09:42:56 +02:00
2018-02-25 11:05:51 +01:00
2019-05-25 18:26:53 +02:00
2018-01-05 15:46:35 +01:00
2017-02-09 08:08:28 +01:00
2016-09-22 15:25:54 +02:00
2019-02-20 10:18:31 +01:00
2018-12-01 09:44:25 +01:00
2018-01-17 09:38:53 +01:00
2016-08-08 14:42:01 -05:00
2017-08-24 17:12:21 -07:00
2019-03-23 13:19:47 +01:00
2016-10-14 11:36:59 -07:00
2016-09-13 02:49:34 +02:00
2017-01-06 10:40:15 +01:00
2016-09-27 21:52:00 -04:00
2016-10-08 11:06:08 -04:00
2018-03-24 11:00:09 +01:00
2018-11-10 07:43:01 -08:00
2018-10-03 17:01:43 -07:00
2017-11-15 15:53:17 +01:00
2016-10-09 12:23:38 -07:00
2016-09-22 19:59:41 -05:00
2019-03-23 13:19:50 +01:00
2018-04-20 08:21:05 +02:00
2017-08-06 18:59:43 -07:00
2016-09-08 15:01:10 -07:00
2016-09-22 02:18:33 -04:00
2019-01-09 16:16:42 +01:00
2019-05-14 19:19:34 +02:00
2016-09-05 16:45:39 +02:00
2016-09-12 20:01:43 +01:00
2016-07-29 15:54:19 -07:00
2016-10-11 15:06:30 -07:00
2017-04-12 12:41:15 +02:00
2016-08-02 19:35:06 -04:00
2016-08-18 15:36:59 +02:00
2019-05-16 19:43:40 +02:00
2017-01-26 08:24:37 +01:00
2016-10-29 12:14:39 -06:00
2019-04-05 22:29:06 +02:00
2016-10-02 22:50:21 -07:00
2018-12-08 13:05:09 +01:00
2018-10-18 09:13:25 +02:00
2019-04-05 22:29:05 +02:00
2016-08-02 19:35:38 -04:00
2016-08-02 19:35:37 -04:00
2016-08-02 19:35:37 -04:00
2016-09-08 22:15:25 -07:00
2016-09-01 16:56:15 -07:00
2016-09-17 08:39:12 -06:00
2019-05-14 19:19:39 +02:00
2016-08-08 12:51:58 -07:00
2018-05-22 16:58:01 +02:00
2016-09-19 12:27:10 +10:00
2016-10-11 15:06:33 -07:00
2016-10-07 18:46:30 -07:00
2016-08-31 15:36:01 +02:00
2018-08-03 07:55:25 +02:00
2016-07-27 14:20:09 -07:00
2018-01-17 09:38:53 +01:00
2018-05-22 16:57:57 +02:00
2017-08-30 10:21:40 +02:00
2019-02-20 10:18:28 +01:00
2016-07-28 16:07:41 -07:00
2017-08-11 08:49:36 -07:00
2018-10-03 17:01:50 -07:00
2016-08-28 23:44:55 -04:00
2016-09-05 13:52:39 +02:00
2019-05-31 06:48:17 -07:00
2016-10-05 18:23:36 -04:00
2019-04-17 08:36:39 +02:00
2018-05-30 07:50:24 +02:00
2019-04-20 09:07:54 +02:00
2018-08-15 18:14:45 +02:00
2017-01-26 08:24:44 +01:00
2016-08-11 15:39:38 +05:30
2016-10-17 09:50:56 -07:00
2018-08-15 18:14:43 +02:00
2018-09-05 09:20:10 +02:00
2016-09-15 09:51:14 -04:00
2018-11-13 11:17:02 -08:00
2018-06-06 16:44:34 +02:00
2016-09-27 14:35:21 +08:00
2018-08-09 12:18:00 +02:00
2016-08-31 14:43:35 -07:00
2017-06-29 13:00:30 +02:00
2016-09-22 17:02:55 +02:00
2018-01-02 20:35:17 +01:00
2016-07-28 16:07:41 -07:00
2016-08-22 10:10:12 -07:00
2017-10-12 11:51:21 +02:00
2017-09-27 14:39:19 +02:00
2018-05-01 15:13:05 -07:00
2016-09-30 11:46:40 +02:00
2018-11-27 16:09:41 +01:00
2017-04-21 09:31:21 +02:00
2016-09-13 08:08:24 +02:00
2019-05-08 07:19:08 +02:00
2017-03-18 19:14:29 +08:00
2016-08-08 14:42:02 -05:00
2018-09-09 20:01:23 +02:00
2018-01-31 12:55:52 +01:00
2017-07-27 15:08:03 -07:00
2016-08-16 18:49:56 +02:00
2016-08-01 21:44:52 +03:00
2017-02-04 09:47:09 +01:00
2019-04-17 08:36:47 +02:00
2017-12-25 14:23:37 +01:00
2018-05-01 15:13:05 -07:00
2018-09-19 22:47:17 +02:00
2018-09-19 22:47:17 +02:00
2016-08-31 13:20:15 +02:00
2016-07-28 16:07:41 -07:00
2016-09-30 10:54:03 +02:00
2016-10-08 10:27:10 +02:00
2016-09-21 00:22:59 -04:00
2018-12-05 19:42:42 +01:00
2016-10-07 18:46:27 -07:00
2016-08-04 08:50:07 -04:00
2016-10-07 21:48:36 -04:00
e186b19bc3