From: David Miller <davem@davemloft.net>
To: viro@zeniv.linux.org.uk
Cc: torvalds@linux-foundation.org, linux-arch@vger.kernel.org,
linux-kernel@vger.kernel.org, arnd@arndb.de
Subject: Re: [RFC] regset ->get() API
Date: Fri, 21 Feb 2020 11:22:44 -0800 (PST) [thread overview]
Message-ID: <20200221.112244.1426580944977593272.davem@davemloft.net> (raw)
In-Reply-To: <20200221185903.GA3929948@ZenIV.linux.org.uk>
From: Al Viro <viro@zeniv.linux.org.uk>
Date: Fri, 21 Feb 2020 18:59:03 +0000
> Again, a couple of copy_regset_to_user(), but there's an additional
> twist - GETREGSET of 32bit task on sparc64 will use access_process_vm()
> when trying to fetch L0..L7/I0..I7 of other task, using copy_from_user()
> only when the target is equal to current. For sparc32 this is not
> true - it's always copy_from_user() there, so the values it reports
> for those registers have nothing to do with the target process. That
> part smells like a bug; by the time GETREGSET had been introduced
> sparc32 was not getting much attention, GETREGS worked just fine
> (not reporting L*/I* anyway) and for coredump it was accessing the
> caller's memory. Not sure if anyone cares at that point...
That's definitely a bug and sparc64 is doing it correctly.
next prev parent reply other threads:[~2020-02-21 19:22 UTC|newest]
Thread overview: 13+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-02-17 18:33 [RFC] regset ->get() API Al Viro
2020-02-19 20:01 ` Linus Torvalds
2020-02-20 22:47 ` Al Viro
2020-02-20 22:56 ` Linus Torvalds
2020-02-20 22:56 ` Linus Torvalds
2020-02-20 23:29 ` Al Viro
2020-02-20 23:31 ` Linus Torvalds
2020-02-21 3:30 ` Al Viro
2020-02-21 18:59 ` Al Viro
2020-02-21 19:22 ` David Miller [this message]
2020-02-22 0:41 ` Al Viro
2020-04-13 4:32 ` David Miller
2020-04-13 4:32 ` David Miller
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