On 11/17/21 6:59 PM, Ye Bin wrote: > We got issue as follows: > ================================================================================ > UBSAN: Undefined behaviour in ./include/linux/ktime.h:42:14 > signed integer overflow: > -4966321760114568020 * 1000000000 cannot be represented in type 'long long int' > CPU: 1 PID: 2186 Comm: syz-executor.2 Not tainted 4.19.90+ #12 > Hardware name: linux,dummy-virt (DT) > Call trace: > dump_backtrace+0x0/0x3f0 arch/arm64/kernel/time.c:78 > show_stack+0x28/0x38 arch/arm64/kernel/traps.c:158 > __dump_stack lib/dump_stack.c:77 [inline] > dump_stack+0x170/0x1dc lib/dump_stack.c:118 > ubsan_epilogue+0x18/0xb4 lib/ubsan.c:161 > handle_overflow+0x188/0x1dc lib/ubsan.c:192 > __ubsan_handle_mul_overflow+0x34/0x44 lib/ubsan.c:213 > ktime_set include/linux/ktime.h:42 [inline] > timespec64_to_ktime include/linux/ktime.h:78 [inline] > io_timeout fs/io_uring.c:5153 [inline] > io_issue_sqe+0x42c8/0x4550 fs/io_uring.c:5599 > __io_queue_sqe+0x1b0/0xbc0 fs/io_uring.c:5988 > io_queue_sqe+0x1ac/0x248 fs/io_uring.c:6067 > io_submit_sqe fs/io_uring.c:6137 [inline] > io_submit_sqes+0xed8/0x1c88 fs/io_uring.c:6331 > __do_sys_io_uring_enter fs/io_uring.c:8170 [inline] > __se_sys_io_uring_enter fs/io_uring.c:8129 [inline] > __arm64_sys_io_uring_enter+0x490/0x980 fs/io_uring.c:8129 > invoke_syscall arch/arm64/kernel/syscall.c:53 [inline] > el0_svc_common+0x374/0x570 arch/arm64/kernel/syscall.c:121 > el0_svc_handler+0x190/0x260 arch/arm64/kernel/syscall.c:190 > el0_svc+0x10/0x218 arch/arm64/kernel/entry.S:1017 > ================================================================================ > > As ktime_set only judge 'secs' if big than KTIME_SEC_MAX, but if we pass > negative value maybe lead to overflow. > To address this issue, we must check if 'sec' is negative. > > Signed-off-by: Ye Bin <yebin10@xxxxxxxxxx> > --- > fs/io_uring.c | 3 +++ > 1 file changed, 3 insertions(+) > > diff --git a/fs/io_uring.c b/fs/io_uring.c > index f9e720595860..d8a6446a7921 100644 > --- a/fs/io_uring.c > +++ b/fs/io_uring.c > @@ -6157,6 +6157,9 @@ static int io_timeout_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe, > if (get_timespec64(&data->ts, u64_to_user_ptr(sqe->addr))) > return -EFAULT; > > + if (data->ts.tv_sec < 0 || data->ts.tv_nsec < 0) > + return -EINVAL; > + > data->mode = io_translate_timeout_mode(flags); > hrtimer_init(&data->timer, io_timeout_get_clock(data), data->mode); This seems to only fix one instance of when a timespec is copied in, what about the ones in io_timeout_remove_prep()? -- Jens Axboe
