linux-toradex.git/lib, branch toradex_5.0.y

x86/mm/mem_encrypt: Disable all instrumentation for early SME setup

2019-05-25T16:22:29+00:00

[ Upstream commit b51ce3744f115850166f3d6c292b9c8cb849ad4f ]

Enablement of AMD's Secure Memory Encryption feature is determined very
early after start_kernel() is entered. Part of this procedure involves
scanning the command line for the parameter 'mem_encrypt'.

To determine intended state, the function sme_enable() uses library
functions cmdline_find_option() and strncmp(). Their use occurs early
enough such that it cannot be assumed that any instrumentation subsystem
is initialized.

For example, making calls to a KASAN-instrumented function before KASAN
is set up will result in the use of uninitialized memory and a boot
failure.

When AMD's SME support is enabled, conditionally disable instrumentation
of these dependent functions in lib/string.c and arch/x86/lib/cmdline.c.

 [ bp: Get rid of intermediary nostackp var and cleanup whitespace. ]

Fixes: aca20d546214 ("x86/mm: Add support to make use of Secure Memory Encryption")
Reported-by: Li RongQing 
Signed-off-by: Gary R Hook 
Signed-off-by: Borislav Petkov 
Cc: Alexander Shishkin 
Cc: Andrew Morton 
Cc: Andy Shevchenko 
Cc: Boris Brezillon 
Cc: Coly Li 
Cc: "dave.hansen@linux.intel.com" 
Cc: "H. Peter Anvin" 
Cc: Ingo Molnar 
Cc: Kees Cook 
Cc: Kent Overstreet 
Cc: "luto@kernel.org" 
Cc: Masahiro Yamada 
Cc: Matthew Wilcox 
Cc: "mingo@redhat.com" 
Cc: "peterz@infradead.org" 
Cc: Sebastian Andrzej Siewior 
Cc: Thomas Gleixner 
Cc: x86-ml 
Link: https://lkml.kernel.org/r/155657657552.7116.18363762932464011367.stgit@sosrh3.amd.com
Signed-off-by: Sasha Levin

iov_iter: optimize page_copy_sane()

2019-05-22T05:38:58+00:00

commit 6daef95b8c914866a46247232a048447fff97279 upstream.

Avoid cache line miss dereferencing struct page if we can.

page_copy_sane() mostly deals with order-0 pages.

Extra cache line miss is visible on TCP recvmsg() calls dealing
with GRO packets (typically 45 page frags are attached to one skb).

Bringing the 45 struct pages into cpu cache while copying the data
is not free, since the freeing of the skb (and associated
page frags put_page()) can happen after cache lines have been evicted.

Signed-off-by: Eric Dumazet 
Cc: Al Viro 
Signed-off-by: Al Viro 
Cc: Matthew Wilcox 
Signed-off-by: Greg Kroah-Hartman

iov_iter: Fix build error without CONFIG_CRYPTO

2019-05-10T16:36:08+00:00

[ Upstream commit 27fad74a5a77fe2e1f876db7bf27efcf2ec304b2 ]

If CONFIG_CRYPTO is not set or set to m,
gcc building warn this:

lib/iov_iter.o: In function `hash_and_copy_to_iter':
iov_iter.c:(.text+0x9129): undefined reference to `crypto_stats_get'
iov_iter.c:(.text+0x9152): undefined reference to `crypto_stats_ahash_update'

Reported-by: Hulk Robot 
Fixes: d05f443554b3 ("iov_iter: introduce hash_and_copy_to_iter helper")
Suggested-by: Al Viro 
Signed-off-by: YueHaibing 
Signed-off-by: Al Viro 
Signed-off-by: Sasha Levin

ubsan: Fix nasty -Wbuiltin-declaration-mismatch GCC-9 warnings

2019-05-10T16:36:03+00:00

commit f0996bc2978e02d2ea898101462b960f6119b18f upstream.

Building lib/ubsan.c with gcc-9 results in a ton of nasty warnings like
this one:

    lib/ubsan.c warning: conflicting types for built-in function
         ‘__ubsan_handle_negate_overflow’; expected ‘void(void *, void *)’ [-Wbuiltin-declaration-mismatch]

The kernel's declarations of __ubsan_handle_*() often uses 'unsigned
long' types in parameters while GCC these parameters as 'void *' types,
hence the mismatch.

Fix this by using 'void *' to match GCC's declarations.

Reported-by: Linus Torvalds 
Signed-off-by: Andrey Ryabinin 
Fixes: c6d308534aef ("UBSAN: run-time undefined behavior sanity checker")
Cc: 
Signed-off-by: Linus Torvalds 
Signed-off-by: Greg Kroah-Hartman

sbitmap: order READ/WRITE freed instance and setting clear bit

2019-05-04T07:21:18+00:00

[ Upstream commit e6d1fa584e0dd9bfebaf345e9feea588cf75ead2 ]

Inside sbitmap_queue_clear(), once the clear bit is set, it will be
visiable to allocation path immediately. Meantime READ/WRITE on old
associated instance(such as request in case of blk-mq) may be
out-of-order with the setting clear bit, so race with re-allocation
may be triggered.

Adds one memory barrier for ordering READ/WRITE of the freed associated
instance with setting clear bit for avoiding race with re-allocation.

The following kernel oops triggerd by block/006 on aarch64 may be fixed:

[  142.330954] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000330
[  142.338794] Mem abort info:
[  142.341554]   ESR = 0x96000005
[  142.344632]   Exception class = DABT (current EL), IL = 32 bits
[  142.350500]   SET = 0, FnV = 0
[  142.353544]   EA = 0, S1PTW = 0
[  142.356678] Data abort info:
[  142.359528]   ISV = 0, ISS = 0x00000005
[  142.363343]   CM = 0, WnR = 0
[  142.366305] user pgtable: 64k pages, 48-bit VAs, pgdp = 000000002a3c51c0
[  142.372983] [0000000000000330] pgd=0000000000000000, pud=0000000000000000
[  142.379777] Internal error: Oops: 96000005 [#1] SMP
[  142.384613] Modules linked in: null_blk ib_isert iscsi_target_mod ib_srpt target_core_mod ib_srp scsi_transport_srp vfat fat rpcrdma sunrpc rdma_ucm ib_iser rdma_cm iw_cm libiscsi ib_umad scsi_transport_iscsi ib_ipoib ib_cm mlx5_ib ib_uverbs ib_core sbsa_gwdt crct10dif_ce ghash_ce ipmi_ssif sha2_ce ipmi_devintf sha256_arm64 sg sha1_ce ipmi_msghandler ip_tables xfs libcrc32c mlx5_core sdhci_acpi mlxfw ahci_platform at803x sdhci libahci_platform qcom_emac mmc_core hdma hdma_mgmt i2c_dev [last unloaded: null_blk]
[  142.429753] CPU: 7 PID: 1983 Comm: fio Not tainted 5.0.0.cki #2
[  142.449458] pstate: 00400005 (nzcv daif +PAN -UAO)
[  142.454239] pc : __blk_mq_free_request+0x4c/0xa8
[  142.458830] lr : blk_mq_free_request+0xec/0x118
[  142.463344] sp : ffff00003360f6a0
[  142.466646] x29: ffff00003360f6a0 x28: ffff000010e70000
[  142.471941] x27: ffff801729a50048 x26: 0000000000010000
[  142.477232] x25: ffff00003360f954 x24: ffff7bdfff021440
[  142.482529] x23: 0000000000000000 x22: 00000000ffffffff
[  142.487830] x21: ffff801729810000 x20: 0000000000000000
[  142.493123] x19: ffff801729a50000 x18: 0000000000000000
[  142.498413] x17: 0000000000000000 x16: 0000000000000001
[  142.503709] x15: 00000000000000ff x14: ffff7fe000000000
[  142.509003] x13: ffff8017dcde09a0 x12: 0000000000000000
[  142.514308] x11: 0000000000000001 x10: 0000000000000008
[  142.519597] x9 : ffff8017dcde09a0 x8 : 0000000000002000
[  142.524889] x7 : ffff8017dcde0a00 x6 : 000000015388f9be
[  142.530187] x5 : 0000000000000001 x4 : 0000000000000000
[  142.535478] x3 : 0000000000000000 x2 : 0000000000000000
[  142.540777] x1 : 0000000000000001 x0 : ffff00001041b194
[  142.546071] Process fio (pid: 1983, stack limit = 0x000000006460a0ea)
[  142.552500] Call trace:
[  142.554926]  __blk_mq_free_request+0x4c/0xa8
[  142.559181]  blk_mq_free_request+0xec/0x118
[  142.563352]  blk_mq_end_request+0xfc/0x120
[  142.567444]  end_cmd+0x3c/0xa8 [null_blk]
[  142.571434]  null_complete_rq+0x20/0x30 [null_blk]
[  142.576194]  blk_mq_complete_request+0x108/0x148
[  142.580797]  null_handle_cmd+0x1d4/0x718 [null_blk]
[  142.585662]  null_queue_rq+0x60/0xa8 [null_blk]
[  142.590171]  blk_mq_try_issue_directly+0x148/0x280
[  142.594949]  blk_mq_try_issue_list_directly+0x9c/0x108
[  142.600064]  blk_mq_sched_insert_requests+0xb0/0xd0
[  142.604926]  blk_mq_flush_plug_list+0x16c/0x2a0
[  142.609441]  blk_flush_plug_list+0xec/0x118
[  142.613608]  blk_finish_plug+0x3c/0x4c
[  142.617348]  blkdev_direct_IO+0x3b4/0x428
[  142.621336]  generic_file_read_iter+0x84/0x180
[  142.625761]  blkdev_read_iter+0x50/0x78
[  142.629579]  aio_read.isra.6+0xf8/0x190
[  142.633409]  __io_submit_one.isra.8+0x148/0x738
[  142.637912]  io_submit_one.isra.9+0x88/0xb8
[  142.642078]  __arm64_sys_io_submit+0xe0/0x238
[  142.646428]  el0_svc_handler+0xa0/0x128
[  142.650238]  el0_svc+0x8/0xc
[  142.653104] Code: b9402a63 f9000a7f 3100047f 540000a0 (f9419a81)
[  142.659202] ---[ end trace 467586bc175eb09d ]---

Fixes: ea86ea2cdced20057da ("sbitmap: ammortize cost of clearing bits")
Reported-and-bisected_and_tested-by: Yi Zhang 
Cc: Yi Zhang 
Cc: "jianchao.wang" 
Reviewed-by: Omar Sandoval 
Signed-off-by: Ming Lei 
Signed-off-by: Jens Axboe 
Signed-off-by: Sasha Levin (Microsoft)

lib/Kconfig.debug: fix build error without CONFIG_BLOCK

2019-05-02T08:02:44+00:00

commit ae3d6a323347940f0548bbb4b17f0bb2e9164169 upstream.

If CONFIG_TEST_KMOD is set to M, while CONFIG_BLOCK is not set, XFS and
BTRFS can not be compiled successly.

Link: http://lkml.kernel.org/r/20190410075434.35220-1-yuehaibing@huawei.com
Fixes: d9c6a72d6fa2 ("kmod: add test driver to stress test the module loader")
Signed-off-by: YueHaibing 
Reported-by: Hulk Robot 
Reviewed-by: Kees Cook 
Cc: Masahiro Yamada 
Cc: Petr Mladek 
Cc: Andy Shevchenko 
Cc: Matthew Wilcox 
Cc: Joe Lawrence 
Cc: Robin Murphy 
Cc: Luis Chamberlain 
Cc: 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds 
Signed-off-by: Greg Kroah-Hartman

lib/div64.c: off by one in shift

2019-04-20T07:17:04+00:00

[ Upstream commit cdc94a37493135e355dfc0b0e086d84e3eadb50d ]

fls counts bits starting from 1 to 32 (returns 0 for zero argument).  If
we add 1 we shift right one bit more and loose precision from divisor,
what cause function incorect results with some numbers.

Corrected code was tested in user-space, see bugzilla:
   https://bugzilla.kernel.org/show_bug.cgi?id=202391

Link: http://lkml.kernel.org/r/1548686944-11891-1-git-send-email-sgruszka@redhat.com
Fixes: 658716d19f8f ("div64_u64(): improve precision on 32bit platforms")
Signed-off-by: Stanislaw Gruszka 
Reported-by: Siarhei Volkau 
Tested-by: Siarhei Volkau 
Acked-by: Oleg Nesterov 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds 
Signed-off-by: Sasha Levin

lib/string.c: implement a basic bcmp

2019-04-17T06:39:44+00:00

[ Upstream commit 5f074f3e192f10c9fade898b9b3b8812e3d83342 ]

A recent optimization in Clang (r355672) lowers comparisons of the
return value of memcmp against zero to comparisons of the return value
of bcmp against zero.  This helps some platforms that implement bcmp
more efficiently than memcmp.  glibc simply aliases bcmp to memcmp, but
an optimized implementation is in the works.

This results in linkage failures for all targets with Clang due to the
undefined symbol.  For now, just implement bcmp as a tailcail to memcmp
to unbreak the build.  This routine can be further optimized in the
future.

Other ideas discussed:

 * A weak alias was discussed, but breaks for architectures that define
   their own implementations of memcmp since aliases to declarations are
   not permitted (only definitions). Arch-specific memcmp
   implementations typically declare memcmp in C headers, but implement
   them in assembly.

 * -ffreestanding also is used sporadically throughout the kernel.

 * -fno-builtin-bcmp doesn't work when doing LTO.

Link: https://bugs.llvm.org/show_bug.cgi?id=41035
Link: https://code.woboq.org/userspace/glibc/string/memcmp.c.html#bcmp
Link: https://github.com/llvm/llvm-project/commit/8e16d73346f8091461319a7dfc4ddd18eedcff13
Link: https://github.com/ClangBuiltLinux/linux/issues/416
Link: http://lkml.kernel.org/r/20190313211335.165605-1-ndesaulniers@google.com
Signed-off-by: Nick Desaulniers 
Reported-by: Nathan Chancellor 
Reported-by: Adhemerval Zanella 
Suggested-by: Arnd Bergmann 
Suggested-by: James Y Knight 
Suggested-by: Masahiro Yamada 
Suggested-by: Nathan Chancellor 
Suggested-by: Rasmus Villemoes 
Acked-by: Steven Rostedt (VMware) 
Reviewed-by: Nathan Chancellor 
Tested-by: Nathan Chancellor 
Reviewed-by: Masahiro Yamada 
Reviewed-by: Andy Shevchenko 
Cc: David Laight 
Cc: Rasmus Villemoes 
Cc: Namhyung Kim 
Cc: Greg Kroah-Hartman 
Cc: Alexander Shishkin 
Cc: Dan Williams 
Cc: 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds 
Signed-off-by: Sasha Levin

ARM: 8833/1: Ensure that NEON code always compiles with Clang

2019-04-05T20:34:39+00:00

[ Upstream commit de9c0d49d85dc563549972edc5589d195cd5e859 ]

While building arm32 allyesconfig, I ran into the following errors:

  arch/arm/lib/xor-neon.c:17:2: error: You should compile this file with
  '-mfloat-abi=softfp -mfpu=neon'

  In file included from lib/raid6/neon1.c:27:
  /home/nathan/cbl/prebuilt/lib/clang/8.0.0/include/arm_neon.h:28:2:
  error: "NEON support not enabled"

Building V=1 showed NEON_FLAGS getting passed along to Clang but
__ARM_NEON__ was not getting defined. Ultimately, it boils down to Clang
only defining __ARM_NEON__ when targeting armv7, rather than armv6k,
which is the '-march' value for allyesconfig.

>From lib/Basic/Targets/ARM.cpp in the Clang source:

  // This only gets set when Neon instructions are actually available, unlike
  // the VFP define, hence the soft float and arch check. This is subtly
  // different from gcc, we follow the intent which was that it should be set
  // when Neon instructions are actually available.
  if ((FPU & NeonFPU) && !SoftFloat && ArchVersion >= 7) {
    Builder.defineMacro("__ARM_NEON", "1");
    Builder.defineMacro("__ARM_NEON__");
    // current AArch32 NEON implementations do not support double-precision
    // floating-point even when it is present in VFP.
    Builder.defineMacro("__ARM_NEON_FP",
                        "0x" + Twine::utohexstr(HW_FP & ~HW_FP_DP));
  }

Ard Biesheuvel recommended explicitly adding '-march=armv7-a' at the
beginning of the NEON_FLAGS definitions so that __ARM_NEON__ always gets
definined by Clang. This doesn't functionally change anything because
that code will only run where NEON is supported, which is implicitly
armv7.

Link: https://github.com/ClangBuiltLinux/linux/issues/287

Suggested-by: Ard Biesheuvel 
Signed-off-by: Nathan Chancellor 
Acked-by: Nicolas Pitre 
Reviewed-by: Nick Desaulniers 
Reviewed-by: Stefan Agner 
Signed-off-by: Russell King 
Signed-off-by: Sasha Levin

kprobes: Prohibit probing on bsearch()

2019-04-05T20:34:38+00:00

[ Upstream commit 02106f883cd745523f7766d90a739f983f19e650 ]

Since kprobe breakpoing handler is using bsearch(), probing on this
routine can cause recursive breakpoint problem.

int3
 ->do_int3()
   ->ftrace_int3_handler()
     ->ftrace_location()
       ->ftrace_location_range()
         ->bsearch() -> int3

Prohibit probing on bsearch().

Signed-off-by: Andrea Righi 
Acked-by: Masami Hiramatsu 
Cc: Alexander Shishkin 
Cc: Arnaldo Carvalho de Melo 
Cc: Jiri Olsa 
Cc: Linus Torvalds 
Cc: Mathieu Desnoyers 
Cc: Peter Zijlstra 
Cc: Steven Rostedt 
Cc: Thomas Gleixner 
Link: http://lkml.kernel.org/r/154998813406.31052.8791425358974650922.stgit@devbox
Signed-off-by: Ingo Molnar 
Signed-off-by: Sasha Levin