Dominique wrote:
> Vim-7.4.1841 (and older) built with ubsan (undefined
> sanitizer) on x86 shows a multiplication overflow when
> clicking in the vim terminal for the first time:
>
> term.c:5039:37: runtime error: signed integer overflow: 1464114431 *
> 1000 cannot be represented in type 'long int'
>
> Steps to reproduce:
>
> 1) build vim with ubsan. It can be done by
> uncommenting this line in vim/src/Makefile
>
> SANITIZER_CFLAGS = -g -O0 -fsanitize=undefined -fno-omit-frame-pointer
>
> 2) start vim with:
> $ vim -u NONE --noplugin -c 'set mouse=a' 2> log
>
> 3) left-click in the terminal with the mouse
>
> 4) observe the error in 'log' file.
>
> It happens only on the first click.
> It also only happens on 32-bits Linux x86 and not on x86_64.
>
> Code at term.c:5039:
>
> 5030 /*
> 5031 * Compute the time elapsed since the previous mouse click.
> 5032 */
> 5033 gettimeofday(&mouse_time, NULL);
> 5034 timediff = (mouse_time.tv_usec
> 5035 - orig_mouse_time.tv_usec) / 1000;
> 5036 if (timediff < 0)
> 5037 --orig_mouse_time.tv_sec;
> 5038 timediff += (mouse_time.tv_sec
> !!5039 - orig_mouse_time.tv_sec) * 1000;
>
> Adding printf, I can see that:
>
> * mouse_time.tv_sec is 1464115088 (this value changes slightly
> every time I reproduce the bug, as it depends on time)
> * orig_mouse_time.tv_sec is 0
>
> So the multiplication by 1000 at line 5039 overflows in 32-bits
> on x86. Overflow does not happen on x86_64 as tv_sec is then
> a 64-bits number.
>
> Attached patch fixes it.
Attachment is missing...
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