Re: [PATCH 4.14 17/89] futex: Prevent overflow by strengthen input validation

[Jiri Slaby]

On 01/25/2018, 03:03 PM, Thomas Gleixner wrote:
> On Thu, 25 Jan 2018, Jiri Slaby wrote:
>> On 01/22/2018, 09:44 AM, Greg Kroah-Hartman wrote:
>>> +	if (nr_wake < 0 || nr_requeue < 0)
>>> +		return -EINVAL;
>>
>> This breaks strace's test suite on 4.14.15 (and is present in upstream
>> obviously too):
>>     futex(0x7ff568b44ffc, 0x3, 0xfacefeed, 0xbadda7a0ca7b100d,
>> 0x7ff568b44ffc, 0x9caffee1) = -1: Invalid argument
> 
> And why the hell is strace expecting this to be valid?

You ought to ask somebody else, I was confused the very same way:

My FIX:
https://github.com/strace/strace/pull/16/commits/777587ea509481666274df88671949b390f05cc3

Their NACK:
https://github.com/strace/strace/pull/16#issuecomment-341614984

thanks,
-- 
js
suse labs