Shifting signed 32-bit value by 31 bits is undefined, so changing significant bit to unsigned. The UBSAN warning calltrace like below:

UBSAN: shift-out-of-bounds in sound/core/seq/seq_clientmgr.c:509:22 left shift of 1 by 31 places cannot be represented in type 'int' ... Call Trace: <TASK> dump_stack_lvl+0x8d/0xcf ubsan_epilogue+0xa/0x44 __ubsan_handle_shift_out_of_bounds+0x1e7/0x208 snd_seq_deliver_single_event.constprop.21+0x191/0x2f0 snd_seq_deliver_event+0x1a2/0x350 snd_seq_kernel_client_dispatch+0x8b/0xb0 snd_seq_client_notify_subscription+0x72/0xa0 snd_seq_ioctl_subscribe_port+0x128/0x160 snd_seq_kernel_client_ctl+0xce/0xf0 snd_seq_oss_create_client+0x109/0x15b alsa_seq_oss_init+0x11c/0x1aa do_one_initcall+0x80/0x440 kernel_init_freeable+0x370/0x3c3 kernel_init+0x1b/0x190 ret_from_fork+0x1f/0x30 </TASK>

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Baisong Zhong zhongbaisong@huawei.com --- v2: update all SNDRV_SEQ_FILTER_* to 1U to keep consistent --- include/uapi/sound/asequencer.h | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/include/uapi/sound/asequencer.h b/include/uapi/sound/asequencer.h index 6d4a2c60808d..00d2703e8fca 100644 --- a/include/uapi/sound/asequencer.h +++ b/include/uapi/sound/asequencer.h @@ -328,10 +328,10 @@ typedef int __bitwise snd_seq_client_type_t; #define KERNEL_CLIENT ((__force snd_seq_client_type_t) 2)

/* event filter flags */ -#define SNDRV_SEQ_FILTER_BROADCAST (1<<0) /* accept broadcast messages */ -#define SNDRV_SEQ_FILTER_MULTICAST (1<<1) /* accept multicast messages */ -#define SNDRV_SEQ_FILTER_BOUNCE (1<<2) /* accept bounce event in error */ -#define SNDRV_SEQ_FILTER_USE_EVENT (1<<31) /* use event filter */ +#define SNDRV_SEQ_FILTER_BROADCAST (1U<<0) /* accept broadcast messages */ +#define SNDRV_SEQ_FILTER_MULTICAST (1U<<1) /* accept multicast messages */ +#define SNDRV_SEQ_FILTER_BOUNCE (1U<<2) /* accept bounce event in error */ +#define SNDRV_SEQ_FILTER_USE_EVENT (1U<<31) /* use event filter */

struct snd_seq_client_info { int client; /* client number to inquire */