linux-toradex.git/lib, branch v4.9-rc7

mpi: Fix NULL ptr dereference in mpi_powm() [ver #3]

2016-11-25T01:57:50+00:00

This fixes CVE-2016-8650.

If mpi_powm() is given a zero exponent, it wants to immediately return
either 1 or 0, depending on the modulus.  However, if the result was
initalised with zero limb space, no limbs space is allocated and a
NULL-pointer exception ensues.

Fix this by allocating a minimal amount of limb space for the result when
the 0-exponent case when the result is 1 and not touching the limb space
when the result is 0.

This affects the use of RSA keys and X.509 certificates that carry them.

BUG: unable to handle kernel NULL pointer dereference at           (null)
IP: [] mpi_powm+0x32/0x7e6
PGD 0
Oops: 0002 [#1] SMP
Modules linked in:
CPU: 3 PID: 3014 Comm: keyctl Not tainted 4.9.0-rc6-fscache+ #278
Hardware name: ASUS All Series/H97-PLUS, BIOS 2306 10/09/2014
task: ffff8804011944c0 task.stack: ffff880401294000
RIP: 0010:[]  [] mpi_powm+0x32/0x7e6
RSP: 0018:ffff880401297ad8  EFLAGS: 00010212
RAX: 0000000000000000 RBX: ffff88040868bec0 RCX: ffff88040868bba0
RDX: ffff88040868b260 RSI: ffff88040868bec0 RDI: ffff88040868bee0
RBP: ffff880401297ba8 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000047 R11: ffffffff8183b210 R12: 0000000000000000
R13: ffff8804087c7600 R14: 000000000000001f R15: ffff880401297c50
FS:  00007f7a7918c700(0000) GS:ffff88041fb80000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000000 CR3: 0000000401250000 CR4: 00000000001406e0
Stack:
 ffff88040868bec0 0000000000000020 ffff880401297b00 ffffffff81376cd4
 0000000000000100 ffff880401297b10 ffffffff81376d12 ffff880401297b30
 ffffffff81376f37 0000000000000100 0000000000000000 ffff880401297ba8
Call Trace:
 [] ? __sg_page_iter_next+0x43/0x66
 [] ? sg_miter_get_next_page+0x1b/0x5d
 [] ? sg_miter_next+0x17/0xbd
 [] ? mpi_read_raw_from_sgl+0xf2/0x146
 [] rsa_verify+0x9d/0xee
 [] ? pkcs1pad_sg_set_buf+0x2e/0xbb
 [] pkcs1pad_verify+0xc0/0xe1
 [] public_key_verify_signature+0x1b0/0x228
 [] x509_check_for_self_signed+0xa1/0xc4
 [] x509_cert_parse+0x167/0x1a1
 [] x509_key_preparse+0x21/0x1a1
 [] asymmetric_key_preparse+0x34/0x61
 [] key_create_or_update+0x145/0x399
 [] SyS_add_key+0x154/0x19e
 [] do_syscall_64+0x80/0x191
 [] entry_SYSCALL64_slow_path+0x25/0x25
Code: 56 41 55 41 54 53 48 81 ec a8 00 00 00 44 8b 71 04 8b 42 04 4c 8b 67 18 45 85 f6 89 45 80 0f 84 b4 06 00 00 85 c0 75 2f 41 ff ce <49> c7 04 24 01 00 00 00 b0 01 75 0b 48 8b 41 18 48 83 38 01 0f
RIP  [] mpi_powm+0x32/0x7e6
 RSP 
CR2: 0000000000000000
---[ end trace d82015255d4a5d8d ]---

Basically, this is a backport of a libgcrypt patch:

	http://git.gnupg.org/cgi-bin/gitweb.cgi?p=libgcrypt.git;a=patch;h=6e1adb05d290aeeb1c230c763970695f4a538526

Fixes: cdec9cb5167a ("crypto: GnuPG based MPI lib - source files (part 1)")
Signed-off-by: Andrey Ryabinin 
Signed-off-by: David Howells 
cc: Dmitry Kasatkin 
cc: linux-ima-devel@lists.sourceforge.net
cc: stable@vger.kernel.org
Signed-off-by: James Morris

Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc

2016-11-21T21:56:17+00:00

Pull sparc fixes from David Miller:

 1) With modern networking cards we can run out of 32-bit DMA space, so
    support 64-bit DMA addressing when possible on sparc64. From Dave
    Tushar.

 2) Some signal frame validation checks are inverted on sparc32, fix
    from Andreas Larsson.

 3) Lockdep tables can get too large in some circumstances on sparc64,
    add a way to adjust the size a bit. From Babu Moger.

 4) Fix NUMA node probing on some sun4v systems, from Thomas Tai.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc:
  sparc: drop duplicate header scatterlist.h
  lockdep: Limit static allocations if PROVE_LOCKING_SMALL is defined
  config: Adding the new config parameter CONFIG_PROVE_LOCKING_SMALL for sparc
  sunbmac: Fix compiler warning
  sunqe: Fix compiler warnings
  sparc64: Enable 64-bit DMA
  sparc64: Enable sun4v dma ops to use IOMMU v2 APIs
  sparc64: Bind PCIe devices to use IOMMU v2 service
  sparc64: Initialize iommu_map_table and iommu_pool
  sparc64: Add ATU (new IOMMU) support
  sparc64: Add FORCE_MAX_ZONEORDER and default to 13
  sparc64: fix compile warning section mismatch in find_node()
  sparc32: Fix inverted invalid_frame_pointer checks on sigreturns
  sparc64: Fix find_node warning if numa node cannot be found

config: Adding the new config parameter CONFIG_PROVE_LOCKING_SMALL for sparc

2016-11-18T19:33:19+00:00

This new config parameter limits the space used for "Lock debugging:
prove locking correctness" by about 4MB. The current sparc systems have
the limitation of 32MB size for kernel size including .text, .data and
.bss sections. With PROVE_LOCKING feature, the kernel size could grow
beyond this limit and causing system boot-up issues. With this option,
kernel limits the size of the entries of lock_chains, stack_trace etc.,
so that kernel fits in required size limit. This is not visible to user
and only used for sparc.

Signed-off-by: Babu Moger 
Acked-by: Sam Ravnborg 
Signed-off-by: David S. Miller

fix iov_iter_advance() for ITER_PIPE

2016-11-17T05:00:48+00:00

iov_iter_advance() needs to decrement iter->count by the number of
bytes we'd moved beyond.  Normal flavours do that, but ITER_PIPE
doesn't and ITER_PIPE generic_file_read_iter() for O_DIRECT files
ends up with a bogus fallback to page cache read, resulting in incorrect
values for file offset and bytes read.

Signed-off-by: Abhi Das 
Signed-off-by: Al Viro

lib/stackdepot: export save/fetch stack for drivers

2016-11-11T16:12:37+00:00

Some drivers would like to record stacktraces in order to aide leak
tracing.  As stackdepot already provides a facility for only storing the
unique traces, thereby reducing the memory required, export that
functionality for use by drivers.

The code was originally created for KASAN and moved under lib in commit
cd11016e5f521 ("mm, kasan: stackdepot implementation.  Enable stackdepot
for SLAB") so that it could be shared with mm/.  In turn, we want to
share it now with drivers.

Link: http://lkml.kernel.org/r/20161108133209.22704-1-chris@chris-wilson.co.uk
Signed-off-by: Chris Wilson 
Cc: Andrey Ryabinin 
Cc: Alexander Potapenko 
Cc: Dmitry Vyukov 
Cc: Joonsoo Kim 
Cc: "Kirill A. Shutemov" 
Cc: Daniel Vetter 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net

2016-10-30T03:33:20+00:00

Pull networking fixes from David Miller:
 "Lots of fixes, mostly drivers as is usually the case.

   1) Don't treat zero DMA address as invalid in vmxnet3, from Alexey
      Khoroshilov.

   2) Fix element timeouts in netfilter's nft_dynset, from Anders K.
      Pedersen.

   3) Don't put aead_req crypto struct on the stack in mac80211, from
      Ard Biesheuvel.

   4) Several uninitialized variable warning fixes from Arnd Bergmann.

   5) Fix memory leak in cxgb4, from Colin Ian King.

   6) Fix bpf handling of VLAN header push/pop, from Daniel Borkmann.

   7) Several VRF semantic fixes from David Ahern.

   8) Set skb->protocol properly in ip6_tnl_xmit(), from Eli Cooper.

   9) Socket needs to be locked in udp_disconnect(), from Eric Dumazet.

  10) Div-by-zero on 32-bit fix in mlx4 driver, from Eugenia Emantayev.

  11) Fix stale link state during failover in NCSCI driver, from Gavin
      Shan.

  12) Fix netdev lower adjacency list traversal, from Ido Schimmel.

  13) Propvide proper handle when emitting notifications of filter
      deletes, from Jamal Hadi Salim.

  14) Memory leaks and big-endian issues in rtl8xxxu, from Jes Sorensen.

  15) Fix DESYNC_FACTOR handling in ipv6, from Jiri Bohac.

  16) Several routing offload fixes in mlxsw driver, from Jiri Pirko.

  17) Fix broadcast sync problem in TIPC, from Jon Paul Maloy.

  18) Validate chunk len before using it in SCTP, from Marcelo Ricardo
      Leitner.

  19) Revert a netns locking change that causes regressions, from Paul
      Moore.

  20) Add recursion limit to GRO handling, from Sabrina Dubroca.

  21) GFP_KERNEL in irq context fix in ibmvnic, from Thomas Falcon.

  22) Avoid accessing stale vxlan/geneve socket in data path, from
      Pravin Shelar"

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (189 commits)
  geneve: avoid using stale geneve socket.
  vxlan: avoid using stale vxlan socket.
  qede: Fix out-of-bound fastpath memory access
  net: phy: dp83848: add dp83822 PHY support
  enic: fix rq disable
  tipc: fix broadcast link synchronization problem
  ibmvnic: Fix missing brackets in init_sub_crq_irqs
  ibmvnic: Fix releasing of sub-CRQ IRQs in interrupt context
  Revert "ibmvnic: Fix releasing of sub-CRQ IRQs in interrupt context"
  arch/powerpc: Update parameters for csum_tcpudp_magic & csum_tcpudp_nofold
  net/mlx4_en: Save slave ethtool stats command
  net/mlx4_en: Fix potential deadlock in port statistics flow
  net/mlx4: Fix firmware command timeout during interrupt test
  net/mlx4_core: Do not access comm channel if it has not yet been initialized
  net/mlx4_en: Fix panic during reboot
  net/mlx4_en: Process all completions in RX rings after port goes up
  net/mlx4_en: Resolve dividing by zero in 32-bit system
  net/mlx4_core: Change the default value of enable_qos
  net/mlx4_core: Avoid setting ports to auto when only one port type is supported
  net/mlx4_core: Fix the resource-type enum in res tracker to conform to FW spec
  ...

lib/genalloc.c: start search from start of chunk

2016-10-28T01:43:43+00:00

gen_pool_alloc_algo() iterates over the chunks of a pool trying to find
a contiguous block of memory that satisfies the allocation request.

The shortcut

	if (size > atomic_read(&chunk->avail))
		continue;

makes the loop skip over chunks that do not have enough bytes left to
fulfill the request.  There are two situations, though, where an
allocation might still fail:

(1) The available memory is not contiguous, i.e.  the request cannot
    be fulfilled due to external fragmentation.

(2) A race condition.  Another thread runs the same code concurrently
    and is quicker to grab the available memory.

In those situations, the loop calls pool->algo() to search the entire
chunk, and pool->algo() returns some value that is >= end_bit to
indicate that the search failed.  This return value is then assigned to
start_bit.  The variables start_bit and end_bit describe the range that
should be searched, and this range should be reset for every chunk that
is searched.  Today, the code fails to reset start_bit to 0.  As a
result, prefixes of subsequent chunks are ignored.  Memory allocations
might fail even though there is plenty of room left in these prefixes of
those other chunks.

Fixes: 7f184275aa30 ("lib, Make gen_pool memory allocator lockless")
Link: http://lkml.kernel.org/r/1477420604-28918-1-git-send-email-danielmentz@google.com
Signed-off-by: Daniel Mentz 
Reviewed-by: Mathieu Desnoyers 
Acked-by: Will Deacon 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

lib/stackdepot.c: bump stackdepot capacity from 16MB to 128MB

2016-10-28T01:43:43+00:00

KASAN uses stackdepot to memorize stacks for all kmalloc/kfree calls.
Current stackdepot capacity is 16MB (1024 top level entries x 4 pages on
second level).  Size of each stack is (num_frames + 3) * sizeof(long).
Which gives us ~84K stacks.  This capacity was chosen empirically and it
is enough to run kernel normally.

However, when lots of configs are enabled and a fuzzer tries to maximize
code coverage, it easily hits the limit within tens of minutes.  I've
tested for long a time with number of top level entries bumped 4x
(4096).  And I think I've seen overflow only once.  But I don't have all
configs enabled and code coverage has not reached maximum yet.  So bump
it 8x to 8192.

Since we have two-level table, memory cost of this is very moderate --
currently the top-level table is 8KB, with this patch it is 64KB, which
is negligible under KASAN.

Here is some approx math.

128MB allows us to memorize ~670K stacks (assuming stack is ~200b).
I've grepped kernel for kmalloc|kfree|kmem_cache_alloc|kmem_cache_free|
kzalloc|kstrdup|kstrndup|kmemdup and it gives ~60K matches.  Most of
alloc/free call sites are reachable with only one stack.  But some
utility functions can have large fanout.  Assuming average fanout is 5x,
total number of alloc/free stacks is ~300K.

Link: http://lkml.kernel.org/r/1476458416-122131-1-git-send-email-dvyukov@google.com
Signed-off-by: Dmitry Vyukov 
Cc: Andrey Ryabinin 
Cc: Alexander Potapenko 
Cc: Joonsoo Kim 
Cc: Baozeng Ding 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

latent_entropy: raise CONFIG_FRAME_WARN by default

2016-10-28T01:43:43+00:00

When building with the latent_entropy plugin, set the default
CONFIG_FRAME_WARN to 2048, since some __init functions have many basic
blocks that, when instrumented by the latent_entropy plugin, grow beyond
1024 byte stack size on 32-bit builds.

Link: http://lkml.kernel.org/r/20161018211216.GA39687@beast
Signed-off-by: Kees Cook 
Reported-by: kbuild test robot 
Cc: Emese Revfy 
Cc: Ingo Molnar 
Cc: Michal Marek 
Cc: "Paul E. McKenney" 
Cc: Dan Williams 
Cc: Andrey Ryabinin 
Cc: Josh Poimboeuf 
Cc: Tejun Heo 
Cc: Nikolay Aleksandrov 
Cc: Dmitry Vyukov 
Cc: Shuah Khan 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

bpf, test: fix ld_abs + vlan push/pop stress test

2016-10-20T18:39:06+00:00

After commit 636c2628086e ("net: skbuff: Remove errornous length
validation in skb_vlan_pop()") mentioned test case stopped working,
throwing a -12 (ENOMEM) return code. The issue however is not due to
636c2628086e, but rather due to a buggy test case that got uncovered
from the change in behaviour in 636c2628086e.

The data_size of that test case for the skb was set to 1. In the
bpf_fill_ld_abs_vlan_push_pop() handler bpf insns are generated that
loop with: reading skb data, pushing 68 tags, reading skb data,
popping 68 tags, reading skb data, etc, in order to force a skb
expansion and thus trigger that JITs recache skb->data. Problem is
that initial data_size is too small.

While before 636c2628086e, the test silently bailed out due to the
skb->len < VLAN_ETH_HLEN check with returning 0, and now throwing an
error from failing skb_ensure_writable(). Set at least minimum of
ETH_HLEN as an initial length so that on first push of data, equivalent
pop will succeed.

Fixes: 4d9c5c53ac99 ("test_bpf: add bpf_skb_vlan_push/pop() tests")
Signed-off-by: Daniel Borkmann 
Acked-by: Alexei Starovoitov 
Signed-off-by: David S. Miller