From: James Bottomley <jejb@linux.vnet.ibm.com>
To: Dan Williams <dan.j.williams@intel.com>, linux-kernel@vger.kernel.org
Cc: linux-arch@vger.kernel.org,
"Martin K. Petersen" <martin.petersen@oracle.com>,
linux-scsi@vger.kernel.org, kernel-hardening@lists.openwall.com,
qla2xxx-upstream@qlogic.com, tglx@linutronix.de,
torvalds@linux-foundation.org, akpm@linux-foundation.org,
Elena Reshetova <elena.reshetova@intel.com>,
alan@linux.intel.com
Subject: Re: [PATCH v2 17/19] qla2xxx: prevent bounds-check bypass via speculative execution
Date: Thu, 11 Jan 2018 17:19:16 -0800 [thread overview]
Message-ID: <1515719956.3056.37.camel@linux.vnet.ibm.com> (raw)
In-Reply-To: <151571807774.27429.7382333750792304971.stgit@dwillia2-desk3.amr.corp.intel.com>
On Thu, 2018-01-11 at 16:47 -0800, Dan Williams wrote:
> Static analysis reports that 'handle' may be a user controlled value
> that is used as a data dependency to read 'sp' from the
> 'req->outstanding_cmds' array.
Greg already told you it comes from hardware, specifically the hardware
response queue. If you don't believe him, I can confirm it's quite
definitely all copied from the iomem where the mailbox response is, so
it can't be a user controlled value (well, unless the user has some
influence over the firmware of the qla2xxx controller, which probably
means you have other things to worry about than speculative information
leaks).
I think what it actually is is a handle returned in the mailbox that's
used to find other mailbox entries in different queues (the packet
handle actually contains an entry in the lower 16 bits and a queue
designation in the upper). Perhaps the qla2xxx people should comment
on this because the code seems to check and print an error if there's a
problem with the handle being too big, but we don't check the que value
and use it blindly to read into the req_q_map: if handle could be
wrong, couldn't que?
James
next prev parent reply other threads:[~2018-01-12 1:19 UTC|newest]
Thread overview: 59+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-01-12 0:46 [PATCH v2 00/19] prevent bounds-check bypass via speculative execution Dan Williams
2018-01-12 0:46 ` [PATCH v2 01/19] Documentation: document array_ptr Dan Williams
2018-01-12 10:38 ` Geert Uytterhoeven
2018-01-16 21:01 ` Kees Cook
2018-01-12 0:46 ` [PATCH v2 02/19] arm64: implement ifence_array_ptr() Dan Williams
2018-01-12 0:46 ` [PATCH v2 03/19] arm: " Dan Williams
2018-01-12 0:46 ` [PATCH v2 04/19] x86: implement ifence() Dan Williams
2018-01-12 2:27 ` Eric W. Biederman
2018-01-12 3:39 ` Dan Williams
2018-01-12 0:46 ` [PATCH v2 05/19] x86: implement ifence_array_ptr() and array_ptr_mask() Dan Williams
2018-01-12 0:46 ` [PATCH v2 06/19] asm-generic/barrier: mask speculative execution flows Dan Williams
2018-01-12 2:42 ` Eric W. Biederman
2018-01-12 9:12 ` Peter Zijlstra
2018-01-13 0:41 ` Dan Williams
2018-01-15 8:46 ` Peter Zijlstra
2018-01-12 0:47 ` [PATCH v2 07/19] x86: introduce __uaccess_begin_nospec and ASM_IFENCE Dan Williams
2018-01-12 17:51 ` Josh Poimboeuf
2018-01-12 18:21 ` Dan Williams
2018-01-12 18:58 ` Josh Poimboeuf
2018-01-12 19:26 ` Dan Williams
2018-01-12 20:01 ` Linus Torvalds
2018-01-12 20:41 ` Josh Poimboeuf
2018-01-12 0:47 ` [PATCH v2 08/19] x86: use __uaccess_begin_nospec and ASM_IFENCE in get_user paths Dan Williams
2018-01-12 1:11 ` Linus Torvalds
2018-01-12 1:14 ` Dan Williams
2018-01-12 0:47 ` [PATCH v2 09/19] ipv6: prevent bounds-check bypass via speculative execution Dan Williams
2018-01-12 0:47 ` [PATCH v2 10/19] ipv4: " Dan Williams
2018-01-12 7:59 ` Greg KH
2018-01-12 18:47 ` Dan Williams
2018-01-13 8:56 ` Greg KH
2018-01-12 0:47 ` [PATCH v2 11/19] vfs, fdtable: " Dan Williams
2018-01-12 0:47 ` [PATCH v2 12/19] userns: " Dan Williams
2018-01-12 0:47 ` [PATCH v2 13/19] udf: " Dan Williams
2018-01-15 10:32 ` Jan Kara
2018-01-15 17:49 ` Dan Williams
2018-01-12 0:47 ` [PATCH v2 14/19] [media] uvcvideo: " Dan Williams
2018-08-06 21:40 ` Laurent Pinchart
2018-01-12 0:47 ` [PATCH v2 15/19] carl9170: " Dan Williams
2018-01-12 14:42 ` Christian Lamparter
2018-01-12 18:39 ` Dan Williams
2018-01-12 20:01 ` Christian Lamparter
2018-01-12 23:05 ` Dan Williams
2018-01-12 0:47 ` [PATCH v2 16/19] p54: " Dan Williams
2018-01-12 0:47 ` [PATCH v2 17/19] qla2xxx: " Dan Williams
2018-01-12 1:19 ` James Bottomley [this message]
2018-01-12 5:38 ` Dan Williams
2018-01-12 6:05 ` James Bottomley
2018-01-12 0:48 ` [PATCH v2 18/19] cw1200: " Dan Williams
2018-01-12 0:48 ` [PATCH v2 19/19] net: mpls: " Dan Williams
2018-01-12 1:19 ` [PATCH v2 00/19] " Linus Torvalds
2018-01-12 1:41 ` Dan Williams
2018-01-18 13:18 ` Will Deacon
2018-01-18 16:58 ` Dan Williams
2018-01-18 17:05 ` Will Deacon
2018-01-18 21:41 ` Laurent Pinchart
2018-01-13 0:15 ` Tony Luck
2018-01-13 18:51 ` Linus Torvalds
2018-01-16 19:21 ` Tony Luck
2018-01-12 10:02 ` Russell King - ARM Linux
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