From: Kees Cook <keescook@chromium.org>
To: Theodore Ts'o <tytso@mit.edu>, Kees Cook <keescook@chromium.org>,
LKML <linux-kernel@vger.kernel.org>,
David Windsor <dave@nullcore.net>,
Andreas Dilger <adilger.kernel@dilger.ca>,
Ext4 Developers List <linux-ext4@vger.kernel.org>,
Linus Torvalds <torvalds@linux-foundation.org>,
Alexander Viro <viro@zeniv.linux.org.uk>,
Andrew Morton <akpm@linux-foundation.org>,
Andy Lutomirski <luto@kernel.org>,
Christoph Hellwig <hch@infradead.org>,
Christoph Lameter <cl@linux.com>,
"David S. Miller" <davem@davemloft.net>,
Laura Abbott <labbott@redhat.com>,
Mark Rutland <mark.rutland@arm.com>,
"Martin K. Petersen" <martin.petersen@oracle.com>,
Paolo Bonzini <pbonzini@redhat.com>,
Christian Borntraeger <borntraeger@de.ibm.com>,
Christoffer Dall <christoffer.dall@linaro.org>,
Dave Kleikamp <dave.kleikamp@oracle.com>, Jan Kara <jack@suse.cz>,
Luis de Bethencourt <luisbg@kernel.org>,
Marc Zyngier <marc.zyngier@arm.com>,
Rik van Riel <riel@redhat.com>,
Matthew Garrett <mjg59@google.com>,
"linux-fsdevel@vger.kernel.org" <linux-fsdevel@vger.kernel.org>,
linux-arch <linux-arch@vger.kernel.org>,
Network Development <netdev@vger.kernel.org>,
Linux-MM <linux-mm@kvack.org>,
kernel-hardening@lists.openwall.com
Subject: [kernel-hardening] Re: [PATCH 13/38] ext4: Define usercopy region in ext4_inode_cache slab cache
Date: Thu, 11 Jan 2018 15:05:14 -0800 [thread overview]
Message-ID: <CAGXu5jJ6=XXuCD7zm8NuKAy+-Ra3F2SyD+CVFjJ=-kQoXPty-A@mail.gmail.com> (raw)
In-Reply-To: <20180111170119.GB19241@thunk.org>
On Thu, Jan 11, 2018 at 9:01 AM, Theodore Ts'o <tytso@mit.edu> wrote:
> On Wed, Jan 10, 2018 at 06:02:45PM -0800, Kees Cook wrote:
>> The ext4 symlink pathnames, stored in struct ext4_inode_info.i_data
>> and therefore contained in the ext4_inode_cache slab cache, need
>> to be copied to/from userspace.
>
> Symlink operations to/from userspace aren't common or in the hot path,
> and when they are in i_data, limited to at most 60 bytes. Is it worth
> it to copy through a bounce buffer so as to disallow any usercopies
> into struct ext4_inode_info?
If this is the only place it's exposed, yeah, that might be a way to
avoid the per-FS patches. This would, AIUI, require changing
readlink_copy() to include a bounce buffer, and that would require an
allocation. I kind of prefer just leaving the per-FS whitelists, as
then there's no global overhead added.
-Kees
--
Kees Cook
Pixel Security
next prev parent reply other threads:[~2018-01-11 23:05 UTC|newest]
Thread overview: 82+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-01-11 2:02 [kernel-hardening] [PATCH v5 00/38] Hardened usercopy whitelisting Kees Cook
2018-01-11 2:02 ` [kernel-hardening] [PATCH 01/38] usercopy: Remove pointer from overflow report Kees Cook
2018-01-11 2:02 ` [kernel-hardening] [PATCH 02/38] usercopy: Enhance and rename report_usercopy() Kees Cook
2018-01-11 17:06 ` [kernel-hardening] " Christopher Lameter
2018-01-14 20:57 ` Kees Cook
2018-01-11 2:02 ` [kernel-hardening] [PATCH 03/38] usercopy: Include offset in hardened usercopy report Kees Cook
2018-01-11 2:02 ` [kernel-hardening] [PATCH 04/38] lkdtm/usercopy: Adjust test to include an offset to check reporting Kees Cook
2018-01-11 2:02 ` [kernel-hardening] [PATCH 05/38] stddef.h: Introduce sizeof_field() Kees Cook
2018-01-11 2:02 ` [kernel-hardening] [PATCH 06/38] usercopy: Prepare for usercopy whitelisting Kees Cook
2018-01-11 2:02 ` [kernel-hardening] [PATCH 07/38] usercopy: WARN() on slab cache usercopy region violations Kees Cook
2018-01-11 2:02 ` [kernel-hardening] [PATCH 08/38] usercopy: Allow strict enforcement of whitelists Kees Cook
2018-01-11 2:02 ` [kernel-hardening] [PATCH 09/38] usercopy: Mark kmalloc caches as usercopy caches Kees Cook
2019-11-12 7:17 ` Jiri Slaby
2019-11-12 21:21 ` Kees Cook
2019-11-14 21:27 ` Kees Cook
2020-01-23 8:14 ` Jiri Slaby
2020-01-27 23:19 ` Kees Cook
2020-01-28 7:58 ` Christian Borntraeger
2020-01-28 23:01 ` Kees Cook
2020-01-29 9:26 ` Ursula Braun
2020-01-29 16:43 ` Christopher Lameter
2020-01-29 17:07 ` Christian Borntraeger
2020-01-29 17:09 ` Christoph Hellwig
2020-01-29 17:19 ` Christian Borntraeger
2020-01-30 19:23 ` Kees Cook
2020-01-31 12:03 ` Jann Horn
2020-02-01 17:56 ` Kees Cook
2020-02-01 19:27 ` Jann Horn
2020-02-03 7:46 ` Matthew Wilcox
2020-02-03 17:41 ` Christoph Hellwig
2020-02-03 17:20 ` Christopher Lameter
2020-04-07 8:00 ` Vlastimil Babka
2020-04-07 11:05 ` Christian Borntraeger
2020-04-20 7:53 ` Jiri Slaby
2020-04-20 17:43 ` Kees Cook
2020-02-03 17:38 ` Christoph Hellwig
2020-02-03 17:36 ` Christoph Hellwig
2018-01-11 2:02 ` [kernel-hardening] [PATCH 10/38] dcache: Define usercopy region in dentry_cache slab cache Kees Cook
2018-01-11 2:02 ` [kernel-hardening] [PATCH 11/38] vfs: Define usercopy region in names_cache slab caches Kees Cook
2018-01-11 2:02 ` [kernel-hardening] [PATCH 12/38] vfs: Copy struct mount.mnt_id to userspace using put_user() Kees Cook
2018-01-11 2:02 ` [kernel-hardening] [PATCH 13/38] ext4: Define usercopy region in ext4_inode_cache slab cache Kees Cook
2018-01-11 17:01 ` [kernel-hardening] " Theodore Ts'o
2018-01-11 23:05 ` Kees Cook [this message]
2018-01-14 22:34 ` Matthew Wilcox
2018-01-11 2:02 ` [kernel-hardening] [PATCH 14/38] ext2: Define usercopy region in ext2_inode_cache " Kees Cook
2018-01-11 2:02 ` [kernel-hardening] [PATCH 15/38] jfs: Define usercopy region in jfs_ip " Kees Cook
2018-01-11 2:02 ` [kernel-hardening] [PATCH 16/38] befs: Define usercopy region in befs_inode_cache " Kees Cook
2018-01-11 2:02 ` [kernel-hardening] [PATCH 17/38] exofs: Define usercopy region in exofs_inode_cache " Kees Cook
2018-01-11 2:02 ` [kernel-hardening] [PATCH 18/38] orangefs: Define usercopy region in orangefs_inode_cache " Kees Cook
2018-01-11 2:02 ` [kernel-hardening] [PATCH 19/38] ufs: Define usercopy region in ufs_inode_cache " Kees Cook
2018-01-11 2:02 ` [kernel-hardening] [PATCH 20/38] vxfs: Define usercopy region in vxfs_inode " Kees Cook
2018-01-11 2:02 ` [kernel-hardening] [PATCH 21/38] cifs: Define usercopy region in cifs_request " Kees Cook
2018-01-11 2:02 ` [kernel-hardening] [PATCH 22/38] scsi: Define usercopy region in scsi_sense_cache " Kees Cook
2018-01-11 2:02 ` [kernel-hardening] [PATCH 23/38] net: Define usercopy region in struct proto " Kees Cook
2018-01-11 2:02 ` [kernel-hardening] [PATCH 24/38] ip: Define usercopy region in IP " Kees Cook
2018-01-11 2:02 ` [kernel-hardening] [PATCH 25/38] caif: Define usercopy region in caif " Kees Cook
2018-01-11 2:02 ` [kernel-hardening] [PATCH 26/38] sctp: Define usercopy region in SCTP " Kees Cook
2018-01-11 2:02 ` [kernel-hardening] [PATCH 27/38] sctp: Copy struct sctp_sock.autoclose to userspace using put_user() Kees Cook
2018-01-18 21:31 ` [kernel-hardening] " Laura Abbott
2018-01-18 21:36 ` Kees Cook
2018-01-11 2:03 ` [kernel-hardening] [PATCH 28/38] net: Restrict unwhitelisted proto caches to size 0 Kees Cook
2018-01-11 2:03 ` [kernel-hardening] [PATCH 29/38] fork: Define usercopy region in mm_struct slab caches Kees Cook
2018-01-11 2:03 ` [kernel-hardening] [PATCH 30/38] fork: Define usercopy region in thread_stack " Kees Cook
2018-01-11 2:03 ` [kernel-hardening] [PATCH 31/38] fork: Provide usercopy whitelisting for task_struct Kees Cook
2018-01-11 2:03 ` [kernel-hardening] [PATCH 32/38] x86: Implement thread_struct whitelist for hardened usercopy Kees Cook
2018-01-11 2:03 ` [kernel-hardening] [PATCH 33/38] arm64: " Kees Cook
2018-01-15 12:24 ` [kernel-hardening] " Dave P Martin
2018-01-15 20:06 ` Kees Cook
2018-01-16 12:33 ` Dave Martin
2018-03-26 16:22 ` Dave Martin
2018-03-26 17:41 ` Kees Cook
2018-03-27 12:32 ` Dave Martin
2018-01-11 2:03 ` [kernel-hardening] [PATCH 34/38] arm: " Kees Cook
2018-01-11 10:24 ` [kernel-hardening] " Russell King - ARM Linux
2018-01-11 23:21 ` Kees Cook
2018-01-11 2:03 ` [kernel-hardening] [PATCH 35/38] kvm: whitelist struct kvm_vcpu_arch Kees Cook
2018-01-11 2:03 ` [kernel-hardening] [PATCH 36/38] kvm: x86: fix KVM_XEN_HVM_CONFIG ioctl Kees Cook
2018-01-11 2:03 ` [kernel-hardening] [PATCH 37/38] usercopy: Restrict non-usercopy caches to size 0 Kees Cook
2018-01-11 2:03 ` [kernel-hardening] [PATCH 38/38] lkdtm: Update usercopy tests for whitelisting Kees Cook
2018-02-19 16:55 ` [PATCH] signals: Move put_compat_sigset to compat.h to silence hardened usercopy Matt Redfearn
2018-02-19 23:55 ` Kees Cook
2018-03-02 21:40 ` James Hogan
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