From: Rich Felker <dalias@libc.org>
To: Markus Wichmann <nullplan@gmx.net>
Cc: musl@lists.openwall.com, "zhuyan (M)" <zhuyan34@huawei.com>
Subject: Re: [musl] [PATCH] fix coredump when sched_rr_get_interval parameter ts is NULL
Date: Fri, 8 May 2020 14:45:53 -0400 [thread overview]
Message-ID: <20200508184553.GK21576@brightrain.aerifal.cx> (raw)
In-Reply-To: <20200508154737.GA25182@voyager>
On Fri, May 08, 2020 at 05:47:37PM +0200, Markus Wichmann wrote:
> On Fri, May 08, 2020 at 02:46:56PM +0000, zhuyan (M) wrote:
> > In function sched_rr_get_interval, there is a risk of null pointer
> > reference. On line 12, when ts is NULL, dereferencing the null
> > pointer will cause the program coredump.
> >
> > Therefore, it must ensure that ts is not empty before use.
> >
>
> Is calling this function with a NULL pointer sensible? The manpage
> certainly doesn't say so. Usually policy in musl is to not fix
> application bugs, but to dereference pointers without NULL pointer check
> unless there is an explicit requirement in the relevant standards that a
> NULL pointer be accepted.
Indeed, sched_rr_get_interval has no contract to accept a null
pointer, and doesn't even have a plausible reason to want to call it
with one (the only output is in the pointed-to memory).
Rich
prev parent reply other threads:[~2020-05-08 18:46 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <20200508143931.5165-1-zhuyan34@huawei.com>
2020-05-08 14:46 ` zhuyan (M)
2020-05-08 15:47 ` Markus Wichmann
2020-05-08 18:45 ` Rich Felker [this message]
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