From: Cyril Hrubis <chrubis@suse.cz>
To: ltp@lists.linux.it
Subject: [LTP] [PATCH v3 1/3] security/dirtyc0w: Fix bug caused by default umask
Date: Mon, 30 Mar 2020 11:20:46 +0200 [thread overview]
Message-ID: <20200330092046.GB9845@yuki.lan> (raw)
In-Reply-To: <20200330091835.GA9845@yuki.lan>
Hi!
> > The case is only successful when system default umask is 0022.
> > When default umask is 0077 or other values, should clear current umask by umask(0) in setup().
>
> What exactly fails in the dirtyc0w because of non-standard umask?
>
> I can easily understand why fstat and statx fail, since we check the
> file permissions there. Ideally the failure should have been part of the
> patch description.
Looking at the code I guess that the child fails to open the file
created in parent before the setgid/setuid, something like this should
really have been part of the patch description.
--
Cyril Hrubis
chrubis@suse.cz
next prev parent reply other threads:[~2020-03-30 9:20 UTC|newest]
Thread overview: 13+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-03-30 7:27 [LTP] [PATCH v3 0/3] Fix bug caused by default umask Zou Wei
2020-03-30 7:27 ` [LTP] [PATCH v3 1/3] security/dirtyc0w: " Zou Wei
2020-03-30 9:18 ` Cyril Hrubis
2020-03-30 9:20 ` Cyril Hrubis [this message]
2020-03-30 12:33 ` Xiao Yang
2020-03-31 2:30 ` [LTP] 答复: " Zouwei
2020-03-30 12:48 ` [LTP] " Xiao Yang
2020-03-30 12:52 ` Cyril Hrubis
2020-03-30 7:27 ` [LTP] [PATCH v3 2/3] syscalls/fstat: " Zou Wei
2020-03-30 7:27 ` [LTP] [PATCH v3 3/3] syscalls/statx01: " Zou Wei
2020-03-30 7:34 ` [LTP] [PATCH v3 0/3] " Xiao Yang
2020-03-30 8:22 ` [LTP] 答复: " Zouwei
2020-03-30 8:59 ` Xiao Yang
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