Messages in this thread |  | | Subject | Re: [PATCH -next] io_uring: Fix undefined-behaviour in io_issue_sqe | From | yebin <> | Date | Mon, 29 Nov 2021 11:36:13 +0800 |
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On 2021/11/27 21:45, Jens Axboe wrote: > 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@huawei.com> >> --- >> 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()? I will send another new patch to fix the scene you said
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