From: ira.weiny@intel.com
To: Andrew Morton <akpm@linux-foundation.org>,
David Sterba <dsterba@suse.cz>
Cc: Ira Weiny <ira.weiny@intel.com>,
Matthew Wilcox <willy@infradead.org>,
clm@fb.com, josef@toxicpanda.com,
Christoph Hellwig <hch@infradead.org>,
linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org
Subject: [PATCH V2.1] mm/highmem: Add VM_BUG_ON() to mem*_page() calls
Date: Wed, 10 Feb 2021 09:49:28 -0800 [thread overview]
Message-ID: <20210210174928.3156073-1-ira.weiny@intel.com> (raw)
In-Reply-To: <20210210062221.3023586-5-ira.weiny@intel.com>
From: Ira Weiny <ira.weiny@intel.com>
Add VM_BUG_ON bounds checks to ensure the newly lifted and created page
memory operations do not result in corrupted data in neighbor pages.[1][2]
[1] https://lore.kernel.org/lkml/20201210053502.GS1563847@iweiny-DESK2.sc.intel.com/
[2] https://lore.kernel.org/lkml/20210209110931.00f00e47d9a0529fcee2ff01@linux-foundation.org/
Suggested-by: Matthew Wilcox <willy@infradead.org>
Suggested-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ira Weiny <ira.weiny@intel.com>
---
Changes from V2:
Actually, really do VM_BUG_ON... <sigh>
Clean up commit message
---
include/linux/highmem.h | 5 +++++
1 file changed, 5 insertions(+)
diff --git a/include/linux/highmem.h b/include/linux/highmem.h
index 0b5d89621cb9..44170f312ae7 100644
--- a/include/linux/highmem.h
+++ b/include/linux/highmem.h
@@ -283,6 +283,7 @@ static inline void memcpy_page(struct page *dst_page, size_t dst_off,
char *dst = kmap_local_page(dst_page);
char *src = kmap_local_page(src_page);
+ VM_BUG_ON(dst_off + len > PAGE_SIZE || src_off + len > PAGE_SIZE);
memcpy(dst + dst_off, src + src_off, len);
kunmap_local(src);
kunmap_local(dst);
@@ -295,6 +296,7 @@ static inline void memmove_page(struct page *dst_page, size_t dst_off,
char *dst = kmap_local_page(dst_page);
char *src = kmap_local_page(src_page);
+ VM_BUG_ON(dst_off + len > PAGE_SIZE || src_off + len > PAGE_SIZE);
memmove(dst + dst_off, src + src_off, len);
kunmap_local(src);
kunmap_local(dst);
@@ -305,6 +307,7 @@ static inline void memset_page(struct page *page, size_t offset, int val,
{
char *addr = kmap_local_page(page);
+ VM_BUG_ON(offset + len > PAGE_SIZE);
memset(addr + offset, val, len);
kunmap_local(addr);
}
@@ -314,6 +317,7 @@ static inline void memcpy_from_page(char *to, struct page *page,
{
char *from = kmap_local_page(page);
+ VM_BUG_ON(offset + len > PAGE_SIZE);
memcpy(to, from + offset, len);
kunmap_local(from);
}
@@ -323,6 +327,7 @@ static inline void memcpy_to_page(struct page *page, size_t offset,
{
char *to = kmap_local_page(page);
+ VM_BUG_ON(offset + len > PAGE_SIZE);
memcpy(to + offset, from, len);
kunmap_local(to);
}
--
2.28.0.rc0.12.gb6a658bd00c9
next prev parent reply other threads:[~2021-02-10 17:52 UTC|newest]
Thread overview: 31+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-02-10 6:22 [PATCH V2 0/8] btrfs: convert kmaps to core page calls ira.weiny
2021-02-10 6:22 ` [PATCH V2 1/8] mm/highmem: Lift memcpy_[to|from]_page to core ira.weiny
2021-02-10 6:33 ` Chaitanya Kulkarni
2021-02-10 12:53 ` Christoph Hellwig
2021-02-10 6:22 ` [PATCH V2 2/8] mm/highmem: Convert memcpy_[to|from]_page() to kmap_local_page() ira.weiny
2021-02-10 6:37 ` Chaitanya Kulkarni
2021-02-10 12:54 ` Christoph Hellwig
2021-02-10 6:22 ` [PATCH V2 3/8] mm/highmem: Introduce memcpy_page(), memmove_page(), and memset_page() ira.weiny
2021-02-10 6:46 ` Chaitanya Kulkarni
2021-02-10 12:54 ` Christoph Hellwig
2021-02-10 6:22 ` [PATCH V2 4/8] mm/highmem: Add VM_BUG_ON() to mem*_page() calls ira.weiny
2021-02-10 6:57 ` Chaitanya Kulkarni
2021-02-10 16:31 ` Ira Weiny
2021-02-10 12:55 ` Christoph Hellwig
2021-02-10 16:29 ` Ira Weiny
2021-02-10 16:41 ` Christoph Hellwig
2021-02-10 17:04 ` Ira Weiny
2021-02-10 18:56 ` Matthew Wilcox
2021-02-10 21:22 ` Ira Weiny
2021-02-11 18:52 ` David Sterba
2021-02-10 17:49 ` ira.weiny [this message]
2021-02-10 6:22 ` [PATCH V2 5/8] iov_iter: Remove memzero_page() in favor of zero_user() ira.weiny
2021-02-10 12:55 ` Christoph Hellwig
2021-02-10 6:22 ` [PATCH V2 6/8] btrfs: use memcpy_[to|from]_page() and kmap_local_page() ira.weiny
2021-02-10 12:56 ` Christoph Hellwig
2021-02-10 6:22 ` [PATCH V2 7/8] btrfs: use copy_highpage() instead of 2 kmaps() ira.weiny
2021-02-10 12:56 ` Christoph Hellwig
2021-02-10 6:22 ` [PATCH V2 8/8] btrfs: convert to zero_user() ira.weiny
2021-02-10 12:57 ` Christoph Hellwig
2021-02-11 19:38 ` [PATCH V2 0/8] btrfs: convert kmaps to core page calls David Sterba
2021-02-11 21:32 ` Ira Weiny
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=20210210174928.3156073-1-ira.weiny@intel.com \
--to=ira.weiny@intel.com \
--cc=akpm@linux-foundation.org \
--cc=clm@fb.com \
--cc=dsterba@suse.cz \
--cc=hch@infradead.org \
--cc=josef@toxicpanda.com \
--cc=linux-fsdevel@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--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;
as well as URLs for NNTP newsgroup(s).