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From: Florian Weimer <fweimer@redhat.com>
To: Martin Sebor via Libc-alpha <libc-alpha@sourceware.org>
Subject: Re: [PATCH] more out of bounds checking improvements
Date: Mon, 26 Oct 2020 16:41:55 +0100	[thread overview]
Message-ID: <87mu09ata4.fsf@oldenburg2.str.redhat.com> (raw)
In-Reply-To: <176ba75f-4299-073f-8319-66dbf9fe3f42@gmail.com> (Martin Sebor via Libc-alpha's message of "Mon, 26 Oct 2020 09:01:24 -0600")

* Martin Sebor via Libc-alpha:

> Besides attribute access, the change adds attribute nonnull to
> the readv and writev functions in misc/sys/uio.h.  The functions
> don't necessarily access the array elements when their count is
> zero but neither POSIX nor the Linux manual document this so it
> seems appropriate to warn.

This change is questionable because it breaks interoperability with
abstract data types such as std::vector, where the base pointer can be
null when the array is empty.  The kernel does not return EFAULT in this
case, as expected.

I think we need a special case for this.

Thanks,
Florian
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  reply	other threads:[~2020-10-26 15:42 UTC|newest]

Thread overview: 29+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-10-26 15:01 Martin Sebor
2020-10-26 15:41 ` Florian Weimer [this message]
2020-12-09  0:18   ` Martin Sebor
2020-10-26 16:08 ` Joseph Myers
2020-12-09 21:46   ` Martin Sebor
2020-12-18 16:56     ` Ping: " Martin Sebor
2021-01-04 15:54       ` Ping 2: " Martin Sebor
2021-01-10 20:44         ` Ping 3: " Martin Sebor
2021-04-22 21:36           ` Ping 4: " Martin Sebor
2021-04-23 10:31     ` Florian Weimer
2021-04-23 15:06       ` Martin Sebor
2021-04-23 16:01         ` Florian Weimer
2021-05-04 19:58           ` Martin Sebor
2021-05-06 17:03             ` Martin Sebor
2021-05-06 18:15               ` Joseph Myers
2021-05-06 19:40                 ` Martin Sebor
2021-05-07  9:20               ` Andreas Schwab
2021-05-07  9:24                 ` Florian Weimer
2021-05-07 11:48                   ` Andreas Schwab
2021-05-07 19:30                 ` Tulio Magno Quites Machado Filho
2021-05-10 17:23                   ` Joseph Myers
2021-05-10  8:45               ` Florian Weimer
2021-05-10 17:14                 ` Martin Sebor
2021-05-10 17:49                   ` Florian Weimer
2021-05-10 18:37                     ` Martin Sebor
2021-05-10 19:22                       ` Andreas Schwab
2021-05-10 19:50                         ` Florian Weimer
2021-05-10 20:31                           ` Martin Sebor
2021-05-11 10:53                             ` Florian Weimer

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