From: Kees Cook <keescook@chromium.org>
To: Russell King <linux@armlinux.org.uk>
Cc: Kees Cook <keescook@chromium.org>,
Logan Gunthorpe <logang@deltatee.com>,
Martin Oliveira <martin.oliveira@eideticom.com>,
David Hildenbrand <david@redhat.com>,
Andrew Morton <akpm@linux-foundation.org>,
Stephen Rothwell <sfr@canb.auug.org.au>, Zi Yan <ziy@nvidia.com>,
Hari Bathini <hbathini@linux.ibm.com>,
Minchan Kim <minchan@kernel.org>,
Mike Kravetz <mike.kravetz@oracle.com>,
linux-arm-kernel@lists.infradead.org,
Christoph Hellwig <hch@lst.de>,
linux-kernel@vger.kernel.org, linux-hardening@vger.kernel.org
Subject: [PATCH] ARM/dma-mapping: Remove CMA code when not built with CMA
Date: Wed, 9 Mar 2022 09:51:07 -0800 [thread overview]
Message-ID: <20220309175107.195182-1-keescook@chromium.org> (raw)
The MAX_CMA_AREAS could be set to 0, which would result in code that would
attempt to operate beyond the end of a zero-sized array. If CONFIG_CMA
is disabled, just remove this code entirely. Found when building with
-Warray-bounds:
arch/arm/mm/dma-mapping.c:396:22: warning: array subscript <unknown> is outside array bounds of 'str
uct dma_contig_early_reserve[0]' [-Warray-bounds]
396 | dma_mmu_remap[dma_mmu_remap_num].size = size;
| ~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~
arch/arm/mm/dma-mapping.c:389:40: note: while referencing 'dma_mmu_remap'
389 | static struct dma_contig_early_reserve dma_mmu_remap[MAX_CMA_AREAS] __initdata;
| ^~~~~~~~~~~~~
Cc: Russell King <linux@armlinux.org.uk>
Cc: Logan Gunthorpe <logang@deltatee.com>
Cc: Martin Oliveira <martin.oliveira@eideticom.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Zi Yan <ziy@nvidia.com>
Cc: Hari Bathini <hbathini@linux.ibm.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: linux-arm-kernel@lists.infradead.org
Signed-off-by: Kees Cook <keescook@chromium.org>
---
arch/arm/mm/dma-mapping.c | 2 ++
arch/arm/mm/mm.h | 4 ++++
include/linux/cma.h | 4 ----
3 files changed, 6 insertions(+), 4 deletions(-)
diff --git a/arch/arm/mm/dma-mapping.c b/arch/arm/mm/dma-mapping.c
index 4b61541853ea..82ffac621854 100644
--- a/arch/arm/mm/dma-mapping.c
+++ b/arch/arm/mm/dma-mapping.c
@@ -381,6 +381,7 @@ static int __init atomic_pool_init(void)
*/
postcore_initcall(atomic_pool_init);
+#ifdef CONFIG_CMA_AREAS
struct dma_contig_early_reserve {
phys_addr_t base;
unsigned long size;
@@ -435,6 +436,7 @@ void __init dma_contiguous_remap(void)
iotable_init(&map, 1);
}
}
+#endif
static int __dma_update_pte(pte_t *pte, unsigned long addr, void *data)
{
diff --git a/arch/arm/mm/mm.h b/arch/arm/mm/mm.h
index 9ff683612f2a..d7ffccb7fea7 100644
--- a/arch/arm/mm/mm.h
+++ b/arch/arm/mm/mm.h
@@ -88,6 +88,10 @@ extern phys_addr_t arm_lowmem_limit;
void __init bootmem_init(void);
void arm_mm_memblock_reserve(void);
+#ifdef CONFIG_CMA_AREAS
void dma_contiguous_remap(void);
+#else
+static inline void dma_contiguous_remap(void) { }
+#endif
unsigned long __clear_cr(unsigned long mask);
diff --git a/include/linux/cma.h b/include/linux/cma.h
index 90fd742fd1ef..a6f637342740 100644
--- a/include/linux/cma.h
+++ b/include/linux/cma.h
@@ -12,10 +12,6 @@
*/
#ifdef CONFIG_CMA_AREAS
#define MAX_CMA_AREAS (1 + CONFIG_CMA_AREAS)
-
-#else
-#define MAX_CMA_AREAS (0)
-
#endif
#define CMA_MAX_NAME 64
--
2.32.0
next reply other threads:[~2022-03-09 17:51 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-03-09 17:51 Kees Cook [this message]
2022-03-10 7:00 ` [PATCH] ARM/dma-mapping: Remove CMA code when not built with CMA Christoph Hellwig
2022-03-10 8:23 ` David Hildenbrand
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=20220309175107.195182-1-keescook@chromium.org \
--to=keescook@chromium.org \
--cc=akpm@linux-foundation.org \
--cc=david@redhat.com \
--cc=hbathini@linux.ibm.com \
--cc=hch@lst.de \
--cc=linux-arm-kernel@lists.infradead.org \
--cc=linux-hardening@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux@armlinux.org.uk \
--cc=logang@deltatee.com \
--cc=martin.oliveira@eideticom.com \
--cc=mike.kravetz@oracle.com \
--cc=minchan@kernel.org \
--cc=sfr@canb.auug.org.au \
--cc=ziy@nvidia.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).