From: Andrey Konovalov <andreyknvl@google.com>
To: Catalin Marinas <catalin.marinas@arm.com>,
Will Deacon <will.deacon@arm.com>,
Mark Rutland <mark.rutland@arm.com>,
Robin Murphy <robin.murphy@arm.com>,
Kees Cook <keescook@chromium.org>,
Kate Stewart <kstewart@linuxfoundation.org>,
Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
Andrew Morton <akpm@linux-foundation.org>,
Ingo Molnar <mingo@kernel.org>,
"Kirill A . Shutemov" <kirill.shutemov@linux.intel.com>,
Shuah Khan <shuah@kernel.org>,
linux-arm-kernel@lists.infradead.org, linux-doc@vger.kernel.org,
linux-mm@kvack.org, linux-arch@vger.kernel.org,
linux-kselftest@vger.kernel.org, linux-kernel@vger.kernel.org
Cc: Dmitry Vyukov <dvyukov@google.com>,
Kostya Serebryany <kcc@google.com>,
Evgeniy Stepanov <eugenis@google.com>,
Lee Smith <Lee.Smith@arm.com>,
Ramana Radhakrishnan <Ramana.Radhakrishnan@arm.com>,
Jacob Bramley <Jacob.Bramley@arm.com>,
Ruben Ayrapetyan <Ruben.Ayrapetyan@arm.com>,
Chintan Pandya <cpandya@codeaurora.org>,
Luc Van Oostenryck <luc.vanoostenryck@gmail.com>,
Andrey Konovalov <andreyknvl@google.com>
Subject: [PATCH v8 6/8] fs, arm64: untag user address in copy_mount_options
Date: Thu, 8 Nov 2018 15:36:13 +0100 [thread overview]
Message-ID: <12fc6c9e4896b394800776c54b16b26e2003a9df.1541687720.git.andreyknvl@google.com> (raw)
In-Reply-To: <cover.1541687720.git.andreyknvl@google.com>
In copy_mount_options a user address is being subtracted from TASK_SIZE.
If the address is lower than TASK_SIZE, the size is calculated to not
allow the exact_copy_from_user() call to cross TASK_SIZE boundary.
However if the address is tagged, then the size will be calculated
incorrectly.
Untag the address before subtracting.
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
---
fs/namespace.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/fs/namespace.c b/fs/namespace.c
index 98d27da43304..1f1f998d15ed 100644
--- a/fs/namespace.c
+++ b/fs/namespace.c
@@ -2674,7 +2674,7 @@ void *copy_mount_options(const void __user * data)
* the remainder of the page.
*/
/* copy_from_user cannot cross TASK_SIZE ! */
- size = TASK_SIZE - (unsigned long)data;
+ size = TASK_SIZE - (unsigned long)untagged_addr(data);
if (size > PAGE_SIZE)
size = PAGE_SIZE;
--
2.19.1.930.g4563a0d9d0-goog
next prev parent reply other threads:[~2018-11-08 14:36 UTC|newest]
Thread overview: 18+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-11-08 14:36 [PATCH v8 0/8] arm64: untag user pointers passed to the kernel Andrey Konovalov
2018-11-08 14:36 ` [PATCH v8 1/8] arm64: add type casts to untagged_addr macro Andrey Konovalov
2018-11-29 18:22 ` Catalin Marinas
2018-12-06 12:34 ` Andrey Konovalov
2018-11-08 14:36 ` [PATCH v8 2/8] uaccess: add untagged_addr definition for other arches Andrey Konovalov
2018-11-29 18:23 ` Catalin Marinas
2018-12-06 12:36 ` Andrey Konovalov
2018-11-08 14:36 ` [PATCH v8 3/8] arm64: untag user addresses in access_ok and __uaccess_mask_ptr Andrey Konovalov
2018-11-29 18:24 ` Catalin Marinas
2018-11-08 14:36 ` [PATCH v8 4/8] mm, arm64: untag user addresses in mm/gup.c Andrey Konovalov
2018-11-08 14:36 ` [PATCH v8 5/8] lib, arm64: untag addrs passed to strncpy_from_user and strnlen_user Andrey Konovalov
2018-11-08 14:36 ` Andrey Konovalov [this message]
2018-11-08 14:36 ` [PATCH v8 7/8] arm64: update Documentation/arm64/tagged-pointers.txt Andrey Konovalov
2018-11-08 14:36 ` [PATCH v8 8/8] selftests, arm64: add a selftest for passing tagged pointers to kernel Andrey Konovalov
2018-11-08 14:48 ` [PATCH v8 0/8] arm64: untag user pointers passed to the kernel Andrey Konovalov
2018-11-29 18:16 ` Catalin Marinas
2018-12-06 12:44 ` Andrey Konovalov
2018-12-06 14:08 ` Catalin Marinas
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=12fc6c9e4896b394800776c54b16b26e2003a9df.1541687720.git.andreyknvl@google.com \
--to=andreyknvl@google.com \
--cc=Jacob.Bramley@arm.com \
--cc=Lee.Smith@arm.com \
--cc=Ramana.Radhakrishnan@arm.com \
--cc=Ruben.Ayrapetyan@arm.com \
--cc=akpm@linux-foundation.org \
--cc=catalin.marinas@arm.com \
--cc=cpandya@codeaurora.org \
--cc=dvyukov@google.com \
--cc=eugenis@google.com \
--cc=gregkh@linuxfoundation.org \
--cc=kcc@google.com \
--cc=keescook@chromium.org \
--cc=kirill.shutemov@linux.intel.com \
--cc=kstewart@linuxfoundation.org \
--cc=linux-arch@vger.kernel.org \
--cc=linux-arm-kernel@lists.infradead.org \
--cc=linux-doc@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-kselftest@vger.kernel.org \
--cc=linux-mm@kvack.org \
--cc=luc.vanoostenryck@gmail.com \
--cc=mark.rutland@arm.com \
--cc=mingo@kernel.org \
--cc=robin.murphy@arm.com \
--cc=shuah@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).