From: Will Deacon <will.deacon@arm.com>
To: Kassey <kassey1216@gmail.com>
Cc: mark.rutland@arm.com, kassey@126.com, ard.biesheuvel@linaro.org,
catalin.marinas@arm.com, linux-kernel@vger.kernel.org,
willy@infradead.org, robin.murphy@arm.com,
linux-arm-kernel@lists.infradead.org
Subject: Re: arm64: copy_from_user access the last page of ddr has problem on 4.14 kernel
Date: Sun, 20 Jan 2019 02:08:31 +0000 [thread overview]
Message-ID: <20190120020829.GA28576@brain-police> (raw)
In-Reply-To: <CAKwPUoyWy64-o2NgB5iPXNs4UR7bmYjmKk3Ub0X6DND40fCtPA@mail.gmail.com>
On Thu, Jan 17, 2019 at 09:57:17AM +0800, Kassey wrote:
> hi, Will
> it is hard to try on v5.0-rc2 kernel, since there is much port
> job to be done.
> dst kernel buffer is looks overwriten by some same(fix) patter
> start with "mmap" (0x6d6d7061) see below code (data from vmalloc),
> and file is mmaped (include the last phy page of ddr.)
> see below pattern and pieces of code.
Weird!
> not sure if there is boundary issue for copy_from_user, please
> help to suggest if you got some idea from the pattern, thanks.
copy_from_user() doesn't care about the physical address, so I can't see why
it would matter (assuming we haven't done something nuts elsewhere, like
double-allocate the page).
The corruption you have is reasonably regular:
> 0079c00 6d6d 7061 0000 0000 0848 fd8f 0001 0000
> 0079c10 0048 fd8f 0001 0000 0001 0000 0003 0000
> 0079c20 2000 fd83 0001 0000 1fff fd86 0001 0000
> 0079c30 0000 0000 0000 0000 700f 0000 0000 0000
Here's "mmap" again, but the record is twice as long:
> 0079c40 6d6d 7061 0000 0000 f448 ffff 0001 0000
> 0079c50 f748 ffff 0001 0000 0001 0000 0004 0000
> 0079c60 3000 fd8c 0001 0000 2fff fd8e 0001 0000
> 0079c70 0000 0000 0000 0000 700f 0000 0000 0000
> 0079c80 c103 0606 0100 be00 1009 3b00 3b07 0607
> 0079c90 0100 5700 1006 e800 8c03 3103 0100 0a00
> 0079ca0 0000 cf00 bf08 0a00 0100 5700 1006 3700
> 0079cb0 3906 0606 0100 1600 0004 4700 9902 0207
And then the whole structure repeats:
> 0079cc0 6d6d 7061 0000 0000 f808 ffff 0001 0000
> 0079cd0 f1c8 ffff 0001 0000 0001 0000 0005 0000
> 0079ce0 d000 fff8 0001 0000 efff fffa 0001 0000
> 0079cf0 0000 0000 0000 0000 700f 0000 0000 0000
> 0079d00 6d6d 7061 0000 0000 f1c8 ffff 0001 0000
> 0079d10 f388 ffff 0001 0000 0001 0000 0003 0000
> 0079d20 c000 ffdf 0001 0000 6fff fff8 0001 0000
> 0079d30 0000 0000 0000 0000 700f 0000 0000 0000
> 0079d40 9407 0901 0100 5300 0204 b400 d503 0a04
> 0079d50 0100 0000 0001 0200 7309 0202 0100 0200
> 0079d60 5000 0200 7309 0202 0400 ff00 f7ff 94ff
> 0079d70 b400 0208 0100 dc00 0000 b400 5803 0607
> 0079d80 6d6d 7061 0000 0000 f7c8 ffff 0001 0000
Do you have any applications running with the name "mmap"?
Also, have you booted with "memtest" on the command-line, so that we can
rule out any dram aliasing issues and the like?
Will
_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
next prev parent reply other threads:[~2019-01-20 2:08 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <CAKwPUowmzZ2BNi-RmJm3=ENrZ5sxPf1SeT+b9A9iHHSCUQQAUw@mail.gmail.com>
2019-01-16 16:48 ` arm64: copy_from_user access the last page of ddr has problem on 4.14 kernel Will Deacon
2019-01-17 1:57 ` Kassey
2019-01-20 2:08 ` Will Deacon [this message]
2019-02-01 9:46 ` kassey
2019-02-11 11:34 ` Will Deacon
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20190120020829.GA28576@brain-police \
--to=will.deacon@arm.com \
--cc=ard.biesheuvel@linaro.org \
--cc=catalin.marinas@arm.com \
--cc=kassey1216@gmail.com \
--cc=kassey@126.com \
--cc=linux-arm-kernel@lists.infradead.org \
--cc=linux-kernel@vger.kernel.org \
--cc=mark.rutland@arm.com \
--cc=robin.murphy@arm.com \
--cc=willy@infradead.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox