From: Shyam Thombre <sthombre@codeaurora.org>
To: catalin.marinas@arm.com, will.deacon@arm.com,
ard.biesheuvel@arm.com, mark.rutland@arm.com,
anshuman.khandual@arm.com, sashal@kernel.org
Cc: linux-arm-kernel@lists.infradead.org,
linux-kernel@vger.kernel.org,
Shyam Thombre <sthombre@codeaurora.org>
Subject: [PATCH] arm64: mm: reset address tag set by kasan sw tagging
Date: Wed, 10 Jun 2020 16:39:44 +0530 [thread overview]
Message-ID: <1591787384-5823-1-git-send-email-sthombre@codeaurora.org> (raw)
KASAN sw tagging sets a random tag of 8 bits in the top byte of the pointer
returned by the memory allocating functions. So for the functions unaware
of this change, the top 8 bits of the address must be reset which is done
by the function arch_kasan_reset_tag().
Signed-off-by: Shyam Thombre <sthombre@codeaurora.org>
---
arch/arm64/mm/mmu.c | 1 +
1 file changed, 1 insertion(+)
diff --git a/arch/arm64/mm/mmu.c b/arch/arm64/mm/mmu.c
index e7fbc62..eae7655 100644
--- a/arch/arm64/mm/mmu.c
+++ b/arch/arm64/mm/mmu.c
@@ -723,6 +723,7 @@ int kern_addr_valid(unsigned long addr)
pmd_t *pmdp, pmd;
pte_t *ptep, pte;
+ addr = arch_kasan_reset_tag(addr);
if ((((long)addr) >> VA_BITS) != -1UL)
return 0;
--
The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
a Linux Foundation Collaborative Project
next reply other threads:[~2020-06-10 11:11 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-06-10 11:09 Shyam Thombre [this message]
2020-06-10 11:36 ` [PATCH] arm64: mm: reset address tag set by kasan sw tagging Catalin Marinas
2020-06-12 13:57 ` Shyam Thombre
2020-06-15 16:34 ` 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=1591787384-5823-1-git-send-email-sthombre@codeaurora.org \
--to=sthombre@codeaurora.org \
--cc=anshuman.khandual@arm.com \
--cc=ard.biesheuvel@arm.com \
--cc=catalin.marinas@arm.com \
--cc=linux-arm-kernel@lists.infradead.org \
--cc=linux-kernel@vger.kernel.org \
--cc=mark.rutland@arm.com \
--cc=sashal@kernel.org \
--cc=will.deacon@arm.com \
/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;
as well as URLs for NNTP newsgroup(s).