Commit Graph

561 Commits

Author SHA1 Message Date
Thomas Gleixner
1a59d1b8e0 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 156
Based on 1 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license as published by
  the free software foundation either version 2 of the license or at
  your option any later version this program is distributed in the
  hope that it will be useful but without any warranty without even
  the implied warranty of merchantability or fitness for a particular
  purpose see the gnu general public license for more details you
  should have received a copy of the gnu general public license along
  with this program if not write to the free software foundation inc
  59 temple place suite 330 boston ma 02111 1307 usa

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 1334 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Richard Fontana <rfontana@redhat.com>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070033.113240726@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-30 11:26:35 -07:00
Linus Torvalds
280664f558 Merge tag 'modules-for-v5.2' of git://git.kernel.org/pub/scm/linux/kernel/git/jeyu/linux
Pull modules updates from Jessica Yu:

 - Use a separate table to store symbol types instead of hijacking
   fields in struct Elf_Sym

 - Trivial code cleanups

* tag 'modules-for-v5.2' of git://git.kernel.org/pub/scm/linux/kernel/git/jeyu/linux:
  module: add stubs for within_module functions
  kallsyms: store type information in its own array
  vmlinux.lds.h: drop unused __vermagic
2019-05-14 10:55:54 -07:00
Linus Torvalds
7664cd6e3a Merge branch 'next-integrity' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security
Pull intgrity updates from James Morris:
 "This contains just three patches, the remainder were either included
  in other pull requests (eg. audit, lockdown) or will be upstreamed via
  other subsystems (eg. kselftests, Power).

  Included here is one bug fix, one documentation update, and extending
  the x86 IMA arch policy rules to coordinate the different kernel
  module signature verification methods"

* 'next-integrity' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security:
  doc/kernel-parameters.txt: Deprecate ima_appraise_tcb
  x86/ima: add missing include
  x86/ima: require signed kernel modules
2019-05-09 12:54:40 -07:00
Rick Edgecombe
1a7b7d9220 modules: Use vmalloc special flag
Use new flag for handling freeing of special permissioned memory in vmalloc
and remove places where memory was set RW before freeing which is no longer
needed.

Since freeing of VM_FLUSH_RESET_PERMS memory is not supported in an
interrupt by vmalloc, the freeing of init sections is moved to a work
queue. Instead of call_rcu it now uses synchronize_rcu() in the work
queue.

Lastly, there is now a WARN_ON in module_memfree since it should not be
called in an interrupt with special memory as is required for
VM_FLUSH_RESET_PERMS.

Signed-off-by: Rick Edgecombe <rick.p.edgecombe@intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: <akpm@linux-foundation.org>
Cc: <ard.biesheuvel@linaro.org>
Cc: <deneen.t.dock@intel.com>
Cc: <kernel-hardening@lists.openwall.com>
Cc: <kristen@linux.intel.com>
Cc: <linux_dti@icloud.com>
Cc: <will.deacon@arm.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Jessica Yu <jeyu@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Nadav Amit <nadav.amit@gmail.com>
Cc: Rik van Riel <riel@surriel.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20190426001143.4983-18-namit@vmware.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-04-30 12:37:58 +02:00
Nadav Amit
f2c65fb322 x86/modules: Avoid breaking W^X while loading modules
When modules and BPF filters are loaded, there is a time window in
which some memory is both writable and executable. An attacker that has
already found another vulnerability (e.g., a dangling pointer) might be
able to exploit this behavior to overwrite kernel code. Prevent having
writable executable PTEs in this stage.

In addition, avoiding having W+X mappings can also slightly simplify the
patching of modules code on initialization (e.g., by alternatives and
static-key), as would be done in the next patch. This was actually the
main motivation for this patch.

To avoid having W+X mappings, set them initially as RW (NX) and after
they are set as RO set them as X as well. Setting them as executable is
done as a separate step to avoid one core in which the old PTE is cached
(hence writable), and another which sees the updated PTE (executable),
which would break the W^X protection.

Suggested-by: Thomas Gleixner <tglx@linutronix.de>
Suggested-by: Andy Lutomirski <luto@amacapital.net>
Signed-off-by: Nadav Amit <namit@vmware.com>
Signed-off-by: Rick Edgecombe <rick.p.edgecombe@intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: <akpm@linux-foundation.org>
Cc: <ard.biesheuvel@linaro.org>
Cc: <deneen.t.dock@intel.com>
Cc: <kernel-hardening@lists.openwall.com>
Cc: <kristen@linux.intel.com>
Cc: <linux_dti@icloud.com>
Cc: <will.deacon@arm.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Jessica Yu <jeyu@kernel.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Rik van Riel <riel@surriel.com>
Link: https://lkml.kernel.org/r/20190426001143.4983-12-namit@vmware.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-04-30 12:37:55 +02:00
Eugene Loh
1c7651f437 kallsyms: store type information in its own array
When a module is loaded, its symbols' Elf_Sym information is stored
in a symtab.  Further, type information is also captured.  Since
Elf_Sym has no type field, historically the st_info field has been
hijacked for storing type:  st_info was overwritten.

commit 5439c985c5 ("module: Overwrite
st_size instead of st_info") changes that practice, as its one-liner
indicates.  Unfortunately, this change overwrites symbol size,
information that a tool like DTrace expects to find.

Allocate a typetab array to store type information so that no Elf_Sym
field needs to be overwritten.

Fixes: 5439c985c5 ("module: Overwrite st_size instead of st_info")
Signed-off-by: Eugene Loh <eugene.loh@oracle.com>
Reviewed-by: Nick Alcock <nick.alcock@oracle.com>
[jeyu: renamed typeoff -> typeoffs ]
Signed-off-by: Jessica Yu <jeyu@kernel.org>
2019-03-28 15:00:37 +01:00
Mimi Zohar
8db5da0b86 x86/ima: require signed kernel modules
Have the IMA architecture specific policy require signed kernel modules
on systems with secure boot mode enabled; and coordinate the different
signature verification methods, so only one signature is required.

Requiring appended kernel module signatures may be configured, enabled
on the boot command line, or with this patch enabled in secure boot
mode.  This patch defines set_module_sig_enforced().

To coordinate between appended kernel module signatures and IMA
signatures, only define an IMA MODULE_CHECK policy rule if
CONFIG_MODULE_SIG is not enabled.  A custom IMA policy may still define
and require an IMA signature.

Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
Reviewed-by: Luis Chamberlain <mcgrof@kernel.org>
Acked-by: Jessica Yu <jeyu@kernel.org>
2019-03-27 10:36:44 -04:00
Rasmus Villemoes
a4507fedcd dynamic_debug: add static inline stub for ddebug_add_module
For symmetry with ddebug_remove_module, and to avoid a bit of ifdeffery
in module.c, move the declaration of ddebug_add_module inside #if
defined(CONFIG_DYNAMIC_DEBUG) and add a corresponding no-op stub in the
#else branch.

Link: http://lkml.kernel.org/r/20190212214150.4807-10-linux@rasmusvillemoes.dk
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Acked-by: Jason Baron <jbaron@akamai.com>
Cc: David Sterba <dsterba@suse.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Petr Mladek <pmladek@suse.com>
Cc: "Rafael J . Wysocki" <rafael.j.wysocki@intel.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-03-07 18:32:00 -08:00
Rasmus Villemoes
513770f54e dynamic_debug: move pr_err from module.c to ddebug_add_module
This serves two purposes: First, we get a diagnostic if (though
extremely unlikely), any of the calls of ddebug_add_module for built-in
code fails, effectively disabling dynamic_debug.  Second, I want to make
struct _ddebug opaque, and avoid accessing any of its members outside
dynamic_debug.[ch].

Link: http://lkml.kernel.org/r/20190212214150.4807-9-linux@rasmusvillemoes.dk
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Acked-by: Jason Baron <jbaron@akamai.com>
Cc: David Sterba <dsterba@suse.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Petr Mladek <pmladek@suse.com>
Cc: "Rafael J . Wysocki" <rafael.j.wysocki@intel.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-03-07 18:32:00 -08:00
Masahiro Yamada
e9666d10a5 jump_label: move 'asm goto' support test to Kconfig
Currently, CONFIG_JUMP_LABEL just means "I _want_ to use jump label".

The jump label is controlled by HAVE_JUMP_LABEL, which is defined
like this:

  #if defined(CC_HAVE_ASM_GOTO) && defined(CONFIG_JUMP_LABEL)
  # define HAVE_JUMP_LABEL
  #endif

We can improve this by testing 'asm goto' support in Kconfig, then
make JUMP_LABEL depend on CC_HAS_ASM_GOTO.

Ugly #ifdef HAVE_JUMP_LABEL will go away, and CONFIG_JUMP_LABEL will
match to the real kernel capability.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc)
Tested-by: Sedat Dilek <sedat.dilek@gmail.com>
2019-01-06 09:46:51 +09:00
Linus Torvalds
b07039b79c Merge tag 'driver-core-4.21-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core
Pull driver core updates from Greg KH:
 "Here is the "big" set of driver core patches for 4.21-rc1.

  It's not really big, just a number of small changes for some reported
  issues, some documentation updates to hopefully make it harder for
  people to abuse the driver model, and some other minor cleanups.

  All of these have been in linux-next for a while with no reported
  issues"

* tag 'driver-core-4.21-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core:
  mm, memory_hotplug: update a comment in unregister_memory()
  component: convert to DEFINE_SHOW_ATTRIBUTE
  sysfs: Disable lockdep for driver bind/unbind files
  driver core: Add missing dev->bus->need_parent_lock checks
  kobject: return error code if writing /sys/.../uevent fails
  driver core: Move async_synchronize_full call
  driver core: platform: Respect return code of platform_device_register_full()
  kref/kobject: Improve documentation
  drivers/base/memory.c: Use DEVICE_ATTR_RO and friends
  driver core: Replace simple_strto{l,ul} by kstrtou{l,ul}
  kernfs: Improve kernfs_notify() poll notification latency
  kobject: Fix warnings in lib/kobject_uevent.c
  kobject: drop unnecessary cast "%llu" for u64
  driver core: fix comments for device_block_probing()
  driver core: Replace simple_strtol by kstrtoint
2018-12-28 20:44:29 -08:00
Linus Torvalds
e0c38a4d1f Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next
Pull networking updates from David Miller:

 1) New ipset extensions for matching on destination MAC addresses, from
    Stefano Brivio.

 2) Add ipv4 ttl and tos, plus ipv6 flow label and hop limit offloads to
    nfp driver. From Stefano Brivio.

 3) Implement GRO for plain UDP sockets, from Paolo Abeni.

 4) Lots of work from Michał Mirosław to eliminate the VLAN_TAG_PRESENT
    bit so that we could support the entire vlan_tci value.

 5) Rework the IPSEC policy lookups to better optimize more usecases,
    from Florian Westphal.

 6) Infrastructure changes eliminating direct manipulation of SKB lists
    wherever possible, and to always use the appropriate SKB list
    helpers. This work is still ongoing...

 7) Lots of PHY driver and state machine improvements and
    simplifications, from Heiner Kallweit.

 8) Various TSO deferral refinements, from Eric Dumazet.

 9) Add ntuple filter support to aquantia driver, from Dmitry Bogdanov.

10) Batch dropping of XDP packets in tuntap, from Jason Wang.

11) Lots of cleanups and improvements to the r8169 driver from Heiner
    Kallweit, including support for ->xmit_more. This driver has been
    getting some much needed love since he started working on it.

12) Lots of new forwarding selftests from Petr Machata.

13) Enable VXLAN learning in mlxsw driver, from Ido Schimmel.

14) Packed ring support for virtio, from Tiwei Bie.

15) Add new Aquantia AQtion USB driver, from Dmitry Bezrukov.

16) Add XDP support to dpaa2-eth driver, from Ioana Ciocoi Radulescu.

17) Implement coalescing on TCP backlog queue, from Eric Dumazet.

18) Implement carrier change in tun driver, from Nicolas Dichtel.

19) Support msg_zerocopy in UDP, from Willem de Bruijn.

20) Significantly improve garbage collection of neighbor objects when
    the table has many PERMANENT entries, from David Ahern.

21) Remove egdev usage from nfp and mlx5, and remove the facility
    completely from the tree as it no longer has any users. From Oz
    Shlomo and others.

22) Add a NETDEV_PRE_CHANGEADDR so that drivers can veto the change and
    therefore abort the operation before the commit phase (which is the
    NETDEV_CHANGEADDR event). From Petr Machata.

23) Add indirect call wrappers to avoid retpoline overhead, and use them
    in the GRO code paths. From Paolo Abeni.

24) Add support for netlink FDB get operations, from Roopa Prabhu.

25) Support bloom filter in mlxsw driver, from Nir Dotan.

26) Add SKB extension infrastructure. This consolidates the handling of
    the auxiliary SKB data used by IPSEC and bridge netfilter, and is
    designed to support the needs to MPTCP which could be integrated in
    the future.

27) Lots of XDP TX optimizations in mlx5 from Tariq Toukan.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1845 commits)
  net: dccp: fix kernel crash on module load
  drivers/net: appletalk/cops: remove redundant if statement and mask
  bnx2x: Fix NULL pointer dereference in bnx2x_del_all_vlans() on some hw
  net/net_namespace: Check the return value of register_pernet_subsys()
  net/netlink_compat: Fix a missing check of nla_parse_nested
  ieee802154: lowpan_header_create check must check daddr
  net/mlx4_core: drop useless LIST_HEAD
  mlxsw: spectrum: drop useless LIST_HEAD
  net/mlx5e: drop useless LIST_HEAD
  iptunnel: Set tun_flags in the iptunnel_metadata_reply from src
  net/mlx5e: fix semicolon.cocci warnings
  staging: octeon: fix build failure with XFRM enabled
  net: Revert recent Spectre-v1 patches.
  can: af_can: Fix Spectre v1 vulnerability
  packet: validate address length if non-zero
  nfc: af_nfc: Fix Spectre v1 vulnerability
  phonet: af_phonet: Fix Spectre v1 vulnerability
  net: core: Fix Spectre v1 vulnerability
  net: minor cleanup in skb_ext_add()
  net: drop the unused helper skb_ext_get()
  ...
2018-12-27 13:04:52 -08:00
Linus Torvalds
7f9f852c75 Merge tag 'modules-for-v4.21' of git://git.kernel.org/pub/scm/linux/kernel/git/jeyu/linux
Pull modules updates from Jessica Yu:

 - Some modules-related kallsyms cleanups and a kallsyms fix for ARM.

 - Include keys from the secondary keyring in module signature
   verification.

* tag 'modules-for-v4.21' of git://git.kernel.org/pub/scm/linux/kernel/git/jeyu/linux:
  ARM: module: Fix function kallsyms on Thumb-2
  module: Overwrite st_size instead of st_info
  module: make it clearer when we're handling kallsyms symbols vs exported symbols
  modsign: use all trusted keys to verify module signature
2018-12-27 12:08:33 -08:00
Matt Mullins
a38d1107f9 bpf: support raw tracepoints in modules
Distributions build drivers as modules, including network and filesystem
drivers which export numerous tracepoints.  This enables
bpf(BPF_RAW_TRACEPOINT_OPEN) to attach to those tracepoints.

Signed-off-by: Matt Mullins <mmullins@fb.com>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-12-18 14:08:12 -08:00
Vincent Whitchurch
93d77e7f14 ARM: module: Fix function kallsyms on Thumb-2
Thumb-2 functions have the lowest bit set in the symbol value in the
symtab.  When kallsyms are generated for the vmlinux, the kallsyms are
generated from the output of nm, and nm clears the lowest bit.

 $ arm-linux-gnueabihf-readelf -a vmlinux | grep show_interrupts
  95947: 8015dc89   686 FUNC    GLOBAL DEFAULT    2 show_interrupts
 $ arm-linux-gnueabihf-nm vmlinux | grep show_interrupts
 8015dc88 T show_interrupts
 $ cat /proc/kallsyms | grep show_interrupts
 8015dc88 T show_interrupts

However, for modules, the kallsyms uses the values in the symbol table
without modification, so for functions in modules, the lowest bit is set
in kallsyms.

 $ arm-linux-gnueabihf-readelf -a drivers/net/tun.ko | grep tun_get_socket
    333: 00002d4d    36 FUNC    GLOBAL DEFAULT    1 tun_get_socket
 $ arm-linux-gnueabihf-nm drivers/net/tun.ko | grep tun_get_socket
 00002d4c T tun_get_socket
 $ cat /proc/kallsyms | grep tun_get_socket
 7f802d4d t tun_get_socket      [tun]

Because of this, the symbol+offset of the crashing instruction shown in
oopses is incorrect when the crash is in a module.  For example, given a
tun_get_socket which starts like this,

 00002d4c <tun_get_socket>:
     2d4c:       6943            ldr     r3, [r0, #20]
     2d4e:       4a07            ldr     r2, [pc, #28]
     2d50:       4293            cmp     r3, r2

a crash when tun_get_socket is called with NULL results in:

 PC is at tun_xdp+0xa3/0xa4 [tun]
 pc : [<7f802d4c>]

As can be seen, the "PC is at" line reports the wrong symbol name, and
the symbol+offset will point to the wrong source line if it is passed to
gdb.

To solve this, add a way for archs to fixup the reading of these module
kallsyms values, and use that to clear the lowest bit for function
symbols on Thumb-2.

After the fix:

 # cat /proc/kallsyms | grep tun_get_socket
 7f802d4c t tun_get_socket       [tun]

 PC is at tun_get_socket+0x0/0x24 [tun]
 pc : [<7f802d4c>]

Signed-off-by: Vincent Whitchurch <vincent.whitchurch@axis.com>
Signed-off-by: Jessica Yu <jeyu@kernel.org>
2018-12-14 20:27:29 +01:00
Vincent Whitchurch
5439c985c5 module: Overwrite st_size instead of st_info
st_info is currently overwritten after relocation and used to store the
elf_type().  However, we're going to need it fix kallsyms on ARM's
Thumb-2 kernels, so preserve st_info and overwrite the st_size field
instead.  st_size is neither used by the module core nor by any
architecture.

Reviewed-by: Miroslav Benes <mbenes@suse.cz>
Reviewed-by: Dave Martin <Dave.Martin@arm.com>
Signed-off-by: Vincent Whitchurch <vincent.whitchurch@axis.com>
Signed-off-by: Jessica Yu <jeyu@kernel.org>
2018-12-14 20:27:21 +01:00
Peter Rajnoha
df44b47965 kobject: return error code if writing /sys/.../uevent fails
Propagate error code back to userspace if writing the /sys/.../uevent
file fails. Before, the write operation always returned with success,
even if we failed to recognize the input string or if we failed to
generate the uevent itself.

With the error codes properly propagated back to userspace, we are
able to react in userspace accordingly by not assuming and awaiting
a uevent that is not delivered.

Signed-off-by: Peter Rajnoha <prajnoha@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-12-06 16:07:43 +01:00
Jessica Yu
2d25bc5523 module: make it clearer when we're handling kallsyms symbols vs exported symbols
The module loader internally works with both exported symbols
represented as struct kernel_symbol, as well as Elf symbols from a
module's symbol table. It's hard to distinguish sometimes which type of
symbol we're handling given that some helper function names are not
consistent or helpful. Take get_ksymbol() for instance - are we
looking for an exported symbol or a kallsyms symbol here? Or symname()
and kernel_symbol_name() - which function handles an exported symbol and
which one an Elf symbol?

Clean up and unify the function naming scheme a bit to make it clear
which kind of symbol we're handling. This change only affects static
functions internal to the module loader.

Reviewed-by: Miroslav Benes <mbenes@suse.cz>
Signed-off-by: Jessica Yu <jeyu@kernel.org>
2018-11-29 14:24:13 +01:00
Paul E. McKenney
cb2f55369d modules: Replace synchronize_sched() and call_rcu_sched()
Now that synchronize_rcu() waits for preempt-disable regions of code
as well as RCU read-side critical sections, synchronize_sched() can
be replaced by synchronize_rcu().  Similarly, call_rcu_sched() can be
replaced by call_rcu().  This commit therefore makes these changes.

Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
Acked-by: Jessica Yu <jeyu@kernel.org>
2018-11-27 09:21:43 -08:00
Ard Biesheuvel
e872267b8b jump_table: Move entries into ro_after_init region
The __jump_table sections emitted into the core kernel and into
each module consist of statically initialized references into
other parts of the code, and with the exception of entries that
point into init code, which are defused at post-init time, these
data structures are never modified.

So let's move them into the ro_after_init section, to prevent them
from being corrupted inadvertently by buggy code, or deliberately
by an attacker.

Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Kees Cook <keescook@chromium.org>
Acked-by: Jessica Yu <jeyu@kernel.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-s390@vger.kernel.org
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Link: https://lkml.kernel.org/r/20180919065144.25010-9-ard.biesheuvel@linaro.org
2018-09-27 17:56:49 +02:00
Ard Biesheuvel
7290d58095 module: use relative references for __ksymtab entries
An ordinary arm64 defconfig build has ~64 KB worth of __ksymtab entries,
each consisting of two 64-bit fields containing absolute references, to
the symbol itself and to a char array containing its name, respectively.

When we build the same configuration with KASLR enabled, we end up with an
additional ~192 KB of relocations in the .init section, i.e., one 24 byte
entry for each absolute reference, which all need to be processed at boot
time.

Given how the struct kernel_symbol that describes each entry is completely
local to module.c (except for the references emitted by EXPORT_SYMBOL()
itself), we can easily modify it to contain two 32-bit relative references
instead.  This reduces the size of the __ksymtab section by 50% for all
64-bit architectures, and gets rid of the runtime relocations entirely for
architectures implementing KASLR, either via standard PIE linking (arm64)
or using custom host tools (x86).

Note that the binary search involving __ksymtab contents relies on each
section being sorted by symbol name.  This is implemented based on the
input section names, not the names in the ksymtab entries, so this patch
does not interfere with that.

Given that the use of place-relative relocations requires support both in
the toolchain and in the module loader, we cannot enable this feature for
all architectures.  So make it dependent on whether
CONFIG_HAVE_ARCH_PREL32_RELOCATIONS is defined.

Link: http://lkml.kernel.org/r/20180704083651.24360-4-ard.biesheuvel@linaro.org
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Acked-by: Jessica Yu <jeyu@kernel.org>
Acked-by: Michael Ellerman <mpe@ellerman.id.au>
Reviewed-by: Will Deacon <will.deacon@arm.com>
Acked-by: Ingo Molnar <mingo@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: James Morris <james.morris@microsoft.com>
Cc: James Morris <jmorris@namei.org>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Nicolas Pitre <nico@linaro.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Russell King <linux@armlinux.org.uk>
Cc: "Serge E. Hallyn" <serge@hallyn.com>
Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Garnier <thgarnie@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-08-22 10:52:47 -07:00
Linus Torvalds
d190775206 Merge tag 'modules-for-v4.19' of git://git.kernel.org/pub/scm/linux/kernel/git/jeyu/linux
Pull modules updates from Jessica Yu:
 "Summary of modules changes for the 4.19 merge window:

   - Fix modules kallsyms for livepatch. Livepatch modules can have
     SHN_UNDEF symbols in their module symbol tables for later symbol
     resolution, but kallsyms shouldn't be returning these symbols

   - Some code cleanups and minor reshuffling in load_module() were done
     to log the module name when module signature verification fails"

* tag 'modules-for-v4.19' of git://git.kernel.org/pub/scm/linux/kernel/git/jeyu/linux:
  kernel/module: Use kmemdup to replace kmalloc+memcpy
  ARM: module: fix modsign build error
  modsign: log module name in the event of an error
  module: replace VMLINUX_SYMBOL_STR() with __stringify() or string literal
  module: print sensible error code
  module: setup load info before module_sig_check()
  module: make it clear when we're handling the module copy in info->hdr
  module: exclude SHN_UNDEF symbols from kallsyms api
2018-08-17 10:51:22 -07:00
zhong jiang
9be936f4b3 kernel/module: Use kmemdup to replace kmalloc+memcpy
we prefer to the kmemdup rather than kmalloc+memcpy. so just
replace them.

Signed-off-by: zhong jiang <zhongjiang@huawei.com>
Signed-off-by: Jessica Yu <jeyu@kernel.org>
2018-08-02 18:03:17 +02:00
Mimi Zohar
c77b8cdf74 module: replace the existing LSM hook in init_module
Both the init_module and finit_module syscalls call either directly
or indirectly the security_kernel_read_file LSM hook.  This patch
replaces the direct call in init_module with a call to the new
security_kernel_load_data hook and makes the corresponding changes
in SELinux, LoadPin, and IMA.

Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Cc: Jeff Vander Stoep <jeffv@google.com>
Cc: Casey Schaufler <casey@schaufler-ca.com>
Cc: Kees Cook <keescook@chromium.org>
Acked-by: Jessica Yu <jeyu@kernel.org>
Acked-by: Paul Moore <paul@paul-moore.com>
Acked-by: Kees Cook <keescook@chromium.org>
Signed-off-by: James Morris <james.morris@microsoft.com>
2018-07-16 12:31:57 -07:00
Jessica Yu
f314dfea16 modsign: log module name in the event of an error
Now that we have the load_info struct all initialized (including
info->name, which contains the name of the module) before
module_sig_check(), make the load_info struct and hence module name
available to mod_verify_sig() so that we can log the module name in the
event of an error.

Signed-off-by: Jessica Yu <jeyu@kernel.org>
2018-07-02 11:36:17 +02:00