From: Kees Cook <keescook@chromium.org>
To: linux-kernel@vger.kernel.org
Cc: Kees Cook <keescook@chromium.org>,
David Windsor <dave@nullcore.net>, Ingo Molnar <mingo@kernel.org>,
Andrew Morton <akpm@linux-foundation.org>,
Thomas Gleixner <tglx@linutronix.de>,
Andy Lutomirski <luto@kernel.org>,
linux-fsdevel@vger.kernel.org, netdev@vger.kernel.org,
linux-mm@kvack.org, kernel-hardening@lists.openwall.com
Subject: [PATCH v3 24/31] fork: Define usercopy region in mm_struct slab caches
Date: Wed, 20 Sep 2017 13:45:30 -0700 [thread overview]
Message-ID: <1505940337-79069-25-git-send-email-keescook@chromium.org> (raw)
In-Reply-To: <1505940337-79069-1-git-send-email-keescook@chromium.org>
From: David Windsor <dave@nullcore.net>
In support of usercopy hardening, this patch defines a region in the
mm_struct slab caches in which userspace copy operations are allowed.
Only the auxv field is copied to userspace.
cache object allocation:
kernel/fork.c:
#define allocate_mm() (kmem_cache_alloc(mm_cachep, GFP_KERNEL))
dup_mm():
...
mm = allocate_mm();
copy_mm(...):
...
dup_mm();
copy_process(...):
...
copy_mm(...)
_do_fork(...):
...
copy_process(...)
example usage trace:
fs/binfmt_elf.c:
create_elf_tables(...):
...
elf_info = (elf_addr_t *)current->mm->saved_auxv;
...
copy_to_user(..., elf_info, ei_index * sizeof(elf_addr_t))
load_elf_binary(...):
...
create_elf_tables(...);
This region is known as the slab cache's usercopy region. Slab caches can
now check that each copy operation involving cache-managed memory falls
entirely within the slab's usercopy region.
This patch is modified from Brad Spengler/PaX Team's PAX_USERCOPY
whitelisting code in the last public patch of grsecurity/PaX based on my
understanding of the code. Changes or omissions from the original code are
mine and don't reflect the original grsecurity/PaX code.
Signed-off-by: David Windsor <dave@nullcore.net>
[kees: adjust commit log, split patch, provide usage trace]
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
Acked-by: Rik van Riel <riel@redhat.com>
---
kernel/fork.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)
diff --git a/kernel/fork.c b/kernel/fork.c
index 10646182440f..dc1437f8b702 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -2207,9 +2207,11 @@ void __init proc_caches_init(void)
* maximum number of CPU's we can ever have. The cpumask_allocation
* is at the end of the structure, exactly for that reason.
*/
- mm_cachep = kmem_cache_create("mm_struct",
+ mm_cachep = kmem_cache_create_usercopy("mm_struct",
sizeof(struct mm_struct), ARCH_MIN_MMSTRUCT_ALIGN,
SLAB_HWCACHE_ALIGN|SLAB_PANIC|SLAB_NOTRACK|SLAB_ACCOUNT,
+ offsetof(struct mm_struct, saved_auxv),
+ sizeof_field(struct mm_struct, saved_auxv),
NULL);
vm_area_cachep = KMEM_CACHE(vm_area_struct, SLAB_PANIC|SLAB_ACCOUNT);
mmap_init();
--
2.7.4
WARNING: multiple messages have this Message-ID (diff)
From: Kees Cook <keescook@chromium.org>
To: linux-kernel@vger.kernel.org
Cc: Kees Cook <keescook@chromium.org>,
David Windsor <dave@nullcore.net>, Ingo Molnar <mingo@kernel.org>,
Andrew Morton <akpm@linux-foundation.org>,
Thomas Gleixner <tglx@linutronix.de>,
Andy Lutomirski <luto@kernel.org>,
linux-fsdevel@vger.kernel.org, netdev@vger.kernel.org,
linux-mm@kvack.org, kernel-hardening@lists.openwall.com
Subject: [PATCH v3 24/31] fork: Define usercopy region in mm_struct slab caches
Date: Wed, 20 Sep 2017 13:45:30 -0700 [thread overview]
Message-ID: <1505940337-79069-25-git-send-email-keescook@chromium.org> (raw)
In-Reply-To: <1505940337-79069-1-git-send-email-keescook@chromium.org>
From: David Windsor <dave@nullcore.net>
In support of usercopy hardening, this patch defines a region in the
mm_struct slab caches in which userspace copy operations are allowed.
Only the auxv field is copied to userspace.
cache object allocation:
kernel/fork.c:
#define allocate_mm() (kmem_cache_alloc(mm_cachep, GFP_KERNEL))
dup_mm():
...
mm = allocate_mm();
copy_mm(...):
...
dup_mm();
copy_process(...):
...
copy_mm(...)
_do_fork(...):
...
copy_process(...)
example usage trace:
fs/binfmt_elf.c:
create_elf_tables(...):
...
elf_info = (elf_addr_t *)current->mm->saved_auxv;
...
copy_to_user(..., elf_info, ei_index * sizeof(elf_addr_t))
load_elf_binary(...):
...
create_elf_tables(...);
This region is known as the slab cache's usercopy region. Slab caches can
now check that each copy operation involving cache-managed memory falls
entirely within the slab's usercopy region.
This patch is modified from Brad Spengler/PaX Team's PAX_USERCOPY
whitelisting code in the last public patch of grsecurity/PaX based on my
understanding of the code. Changes or omissions from the original code are
mine and don't reflect the original grsecurity/PaX code.
Signed-off-by: David Windsor <dave@nullcore.net>
[kees: adjust commit log, split patch, provide usage trace]
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
Acked-by: Rik van Riel <riel@redhat.com>
---
kernel/fork.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)
diff --git a/kernel/fork.c b/kernel/fork.c
index 10646182440f..dc1437f8b702 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -2207,9 +2207,11 @@ void __init proc_caches_init(void)
* maximum number of CPU's we can ever have. The cpumask_allocation
* is at the end of the structure, exactly for that reason.
*/
- mm_cachep = kmem_cache_create("mm_struct",
+ mm_cachep = kmem_cache_create_usercopy("mm_struct",
sizeof(struct mm_struct), ARCH_MIN_MMSTRUCT_ALIGN,
SLAB_HWCACHE_ALIGN|SLAB_PANIC|SLAB_NOTRACK|SLAB_ACCOUNT,
+ offsetof(struct mm_struct, saved_auxv),
+ sizeof_field(struct mm_struct, saved_auxv),
NULL);
vm_area_cachep = KMEM_CACHE(vm_area_struct, SLAB_PANIC|SLAB_ACCOUNT);
mmap_init();
--
2.7.4
--
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WARNING: multiple messages have this Message-ID (diff)
From: Kees Cook <keescook@chromium.org>
To: linux-kernel@vger.kernel.org
Cc: Kees Cook <keescook@chromium.org>,
David Windsor <dave@nullcore.net>, Ingo Molnar <mingo@kernel.org>,
Andrew Morton <akpm@linux-foundation.org>,
Thomas Gleixner <tglx@linutronix.de>,
Andy Lutomirski <luto@kernel.org>,
linux-fsdevel@vger.kernel.org, netdev@vger.kernel.org,
linux-mm@kvack.org, kernel-hardening@lists.openwall.com
Subject: [kernel-hardening] [PATCH v3 24/31] fork: Define usercopy region in mm_struct slab caches
Date: Wed, 20 Sep 2017 13:45:30 -0700 [thread overview]
Message-ID: <1505940337-79069-25-git-send-email-keescook@chromium.org> (raw)
In-Reply-To: <1505940337-79069-1-git-send-email-keescook@chromium.org>
From: David Windsor <dave@nullcore.net>
In support of usercopy hardening, this patch defines a region in the
mm_struct slab caches in which userspace copy operations are allowed.
Only the auxv field is copied to userspace.
cache object allocation:
kernel/fork.c:
#define allocate_mm() (kmem_cache_alloc(mm_cachep, GFP_KERNEL))
dup_mm():
...
mm = allocate_mm();
copy_mm(...):
...
dup_mm();
copy_process(...):
...
copy_mm(...)
_do_fork(...):
...
copy_process(...)
example usage trace:
fs/binfmt_elf.c:
create_elf_tables(...):
...
elf_info = (elf_addr_t *)current->mm->saved_auxv;
...
copy_to_user(..., elf_info, ei_index * sizeof(elf_addr_t))
load_elf_binary(...):
...
create_elf_tables(...);
This region is known as the slab cache's usercopy region. Slab caches can
now check that each copy operation involving cache-managed memory falls
entirely within the slab's usercopy region.
This patch is modified from Brad Spengler/PaX Team's PAX_USERCOPY
whitelisting code in the last public patch of grsecurity/PaX based on my
understanding of the code. Changes or omissions from the original code are
mine and don't reflect the original grsecurity/PaX code.
Signed-off-by: David Windsor <dave@nullcore.net>
[kees: adjust commit log, split patch, provide usage trace]
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
Acked-by: Rik van Riel <riel@redhat.com>
---
kernel/fork.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)
diff --git a/kernel/fork.c b/kernel/fork.c
index 10646182440f..dc1437f8b702 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -2207,9 +2207,11 @@ void __init proc_caches_init(void)
* maximum number of CPU's we can ever have. The cpumask_allocation
* is at the end of the structure, exactly for that reason.
*/
- mm_cachep = kmem_cache_create("mm_struct",
+ mm_cachep = kmem_cache_create_usercopy("mm_struct",
sizeof(struct mm_struct), ARCH_MIN_MMSTRUCT_ALIGN,
SLAB_HWCACHE_ALIGN|SLAB_PANIC|SLAB_NOTRACK|SLAB_ACCOUNT,
+ offsetof(struct mm_struct, saved_auxv),
+ sizeof_field(struct mm_struct, saved_auxv),
NULL);
vm_area_cachep = KMEM_CACHE(vm_area_struct, SLAB_PANIC|SLAB_ACCOUNT);
mmap_init();
--
2.7.4
next prev parent reply other threads:[~2017-09-20 20:57 UTC|newest]
Thread overview: 133+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-09-20 20:45 [PATCH v3 00/31] Hardened usercopy whitelisting Kees Cook
2017-09-20 20:45 ` [kernel-hardening] " Kees Cook
2017-09-20 20:45 ` Kees Cook
2017-09-20 20:45 ` [PATCH v3 01/31] usercopy: Prepare for " Kees Cook
2017-09-20 20:45 ` [kernel-hardening] " Kees Cook
2017-09-20 20:45 ` Kees Cook
2017-09-21 15:21 ` Christopher Lameter
2017-09-21 15:21 ` [kernel-hardening] " Christopher Lameter
2017-09-20 20:45 ` [PATCH v3 02/31] usercopy: Enforce slab cache usercopy region boundaries Kees Cook
2017-09-20 20:45 ` [kernel-hardening] " Kees Cook
2017-09-20 20:45 ` Kees Cook
2017-09-21 15:23 ` Christopher Lameter
2017-09-21 15:23 ` [kernel-hardening] " Christopher Lameter
2017-09-20 20:45 ` [PATCH v3 03/31] usercopy: Mark kmalloc caches as usercopy caches Kees Cook
2017-09-20 20:45 ` [kernel-hardening] " Kees Cook
2017-09-20 20:45 ` Kees Cook
2017-09-21 15:27 ` Christopher Lameter
2017-09-21 15:27 ` [kernel-hardening] " Christopher Lameter
2017-09-21 15:40 ` Kees Cook
2017-09-21 15:40 ` Kees Cook
2017-09-21 15:40 ` Kees Cook
2017-09-21 16:04 ` Christopher Lameter
2017-09-21 16:04 ` Christopher Lameter
2017-09-21 18:26 ` Kees Cook
2017-09-21 18:26 ` Kees Cook
2017-09-21 18:26 ` Kees Cook
2017-09-20 20:45 ` [PATCH v3 04/31] dcache: Define usercopy region in dentry_cache slab cache Kees Cook
2017-09-20 20:45 ` [kernel-hardening] " Kees Cook
2017-09-20 20:45 ` Kees Cook
2017-09-20 20:45 ` [PATCH v3 05/31] vfs: Define usercopy region in names_cache slab caches Kees Cook
2017-09-20 20:45 ` [kernel-hardening] " Kees Cook
2017-09-20 20:45 ` Kees Cook
2017-09-20 20:45 ` [PATCH v3 06/31] vfs: Copy struct mount.mnt_id to userspace using put_user() Kees Cook
2017-09-20 20:45 ` [kernel-hardening] " Kees Cook
2017-09-20 20:45 ` Kees Cook
2017-09-20 20:45 ` [PATCH v3 07/31] ext4: Define usercopy region in ext4_inode_cache slab cache Kees Cook
2017-09-20 20:45 ` [kernel-hardening] " Kees Cook
2017-09-20 20:45 ` Kees Cook
2017-09-20 20:45 ` [PATCH v3 08/31] ext2: Define usercopy region in ext2_inode_cache " Kees Cook
2017-09-20 20:45 ` [kernel-hardening] " Kees Cook
2017-09-20 20:45 ` Kees Cook
2017-09-20 20:45 ` [PATCH v3 09/31] jfs: Define usercopy region in jfs_ip " Kees Cook
2017-09-20 20:45 ` [kernel-hardening] " Kees Cook
2017-09-20 20:45 ` Kees Cook
2017-09-20 20:45 ` Kees Cook
2017-09-22 2:54 ` Dave Kleikamp
2017-09-22 2:54 ` [kernel-hardening] " Dave Kleikamp
2017-09-22 2:54 ` Dave Kleikamp
2017-09-20 20:45 ` [PATCH v3 10/31] befs: Define usercopy region in befs_inode_cache " Kees Cook
2017-09-20 20:45 ` [kernel-hardening] " Kees Cook
2017-09-20 20:45 ` Kees Cook
2017-09-21 9:34 ` Luis de Bethencourt
2017-09-21 9:34 ` [kernel-hardening] " Luis de Bethencourt
2017-09-21 9:34 ` Luis de Bethencourt
2017-09-20 20:45 ` [PATCH v3 11/31] exofs: Define usercopy region in exofs_inode_cache " Kees Cook
2017-09-20 20:45 ` [kernel-hardening] " Kees Cook
2017-09-20 20:45 ` Kees Cook
2017-09-20 20:45 ` [PATCH v3 12/31] orangefs: Define usercopy region in orangefs_inode_cache " Kees Cook
2017-09-20 20:45 ` [kernel-hardening] " Kees Cook
2017-09-20 20:45 ` Kees Cook
2017-09-20 20:45 ` [PATCH v3 13/31] ufs: Define usercopy region in ufs_inode_cache " Kees Cook
2017-09-20 20:45 ` [kernel-hardening] " Kees Cook
2017-09-20 20:45 ` Kees Cook
2017-09-20 20:45 ` [PATCH v3 14/31] vxfs: Define usercopy region in vxfs_inode " Kees Cook
2017-09-20 20:45 ` [kernel-hardening] " Kees Cook
2017-09-20 20:45 ` Kees Cook
2017-09-20 20:56 ` Christoph Hellwig
2017-09-20 20:56 ` [kernel-hardening] " Christoph Hellwig
2017-09-20 20:56 ` Christoph Hellwig
2017-09-20 21:21 ` Kees Cook
2017-09-20 21:21 ` [kernel-hardening] " Kees Cook
2017-09-20 21:21 ` Kees Cook
2017-09-20 23:22 ` Christoph Hellwig
2017-09-20 23:22 ` [kernel-hardening] " Christoph Hellwig
2017-09-20 23:22 ` Christoph Hellwig
2017-09-20 23:22 ` Christoph Hellwig
2017-09-20 20:45 ` [PATCH v3 15/31] xfs: Define usercopy region in xfs_inode " Kees Cook
2017-09-20 20:45 ` [kernel-hardening] " Kees Cook
2017-09-20 20:45 ` Kees Cook
[not found] ` <1505940337-79069-1-git-send-email-keescook-F7+t8E8rja9g9hUCZPvPmw@public.gmane.org>
2017-09-20 20:45 ` [PATCH v3 16/31] cifs: Define usercopy region in cifs_request " Kees Cook
2017-09-20 20:45 ` [kernel-hardening] " Kees Cook
2017-09-20 20:45 ` Kees Cook
2017-09-20 20:45 ` Kees Cook
2017-09-20 20:45 ` [PATCH v3 17/31] scsi: Define usercopy region in scsi_sense_cache " Kees Cook
2017-09-20 20:45 ` [kernel-hardening] " Kees Cook
2017-09-20 20:45 ` Kees Cook
2017-09-20 20:45 ` [PATCH v3 18/31] net: Define usercopy region in struct proto " Kees Cook
2017-09-20 20:45 ` [kernel-hardening] " Kees Cook
2017-09-20 20:45 ` Kees Cook
2017-09-20 20:45 ` [PATCH v3 19/31] ip: Define usercopy region in IP " Kees Cook
2017-09-20 20:45 ` [kernel-hardening] " Kees Cook
2017-09-20 20:45 ` Kees Cook
2017-09-20 20:45 ` [PATCH v3 20/31] caif: Define usercopy region in caif " Kees Cook
2017-09-20 20:45 ` [kernel-hardening] " Kees Cook
2017-09-20 20:45 ` Kees Cook
2017-09-20 20:45 ` [PATCH v3 21/31] sctp: Define usercopy region in SCTP " Kees Cook
2017-09-20 20:45 ` [kernel-hardening] " Kees Cook
2017-09-20 20:45 ` Kees Cook
2017-09-20 20:45 ` Kees Cook
2017-09-20 20:45 ` [PATCH v3 22/31] sctp: Copy struct sctp_sock.autoclose to userspace using put_user() Kees Cook
2017-09-20 20:45 ` [kernel-hardening] " Kees Cook
2017-09-20 20:45 ` Kees Cook
2017-09-20 20:45 ` Kees Cook
2017-09-20 20:45 ` [PATCH v3 23/31] net: Restrict unwhitelisted proto caches to size 0 Kees Cook
2017-09-20 20:45 ` [kernel-hardening] " Kees Cook
2017-09-20 20:45 ` Kees Cook
2017-09-20 20:45 ` Kees Cook [this message]
2017-09-20 20:45 ` [kernel-hardening] [PATCH v3 24/31] fork: Define usercopy region in mm_struct slab caches Kees Cook
2017-09-20 20:45 ` Kees Cook
2017-09-20 20:45 ` [PATCH v3 25/31] fork: Define usercopy region in thread_stack " Kees Cook
2017-09-20 20:45 ` [kernel-hardening] " Kees Cook
2017-09-20 20:45 ` Kees Cook
2017-09-20 20:45 ` [PATCH v3 26/31] fork: Provide usercopy whitelisting for task_struct Kees Cook
2017-09-20 20:45 ` [kernel-hardening] " Kees Cook
2017-09-20 20:45 ` Kees Cook
2017-09-20 20:45 ` Kees Cook
2017-09-20 20:45 ` [PATCH v3 27/31] x86: Implement thread_struct whitelist for hardened usercopy Kees Cook
2017-09-20 20:45 ` [kernel-hardening] " Kees Cook
2017-09-20 20:45 ` Kees Cook
2017-09-20 20:45 ` [PATCH v3 28/31] arm64: " Kees Cook
2017-09-20 20:45 ` [kernel-hardening] " Kees Cook
2017-09-20 20:45 ` Kees Cook
2017-09-20 20:45 ` Kees Cook
2017-09-20 20:45 ` [PATCH v3 29/31] arm: " Kees Cook
2017-09-20 20:45 ` [kernel-hardening] " Kees Cook
2017-09-20 20:45 ` Kees Cook
2017-09-20 20:45 ` Kees Cook
2017-09-20 20:45 ` [PATCH v3 30/31] usercopy: Restrict non-usercopy caches to size 0 Kees Cook
2017-09-20 20:45 ` [kernel-hardening] " Kees Cook
2017-09-20 20:45 ` Kees Cook
2017-09-20 20:45 ` [PATCH v3 31/31] lkdtm: Update usercopy tests for whitelisting Kees Cook
2017-09-20 20:45 ` [kernel-hardening] " Kees Cook
2017-09-20 20:45 ` Kees Cook
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