20 Nov, 2020

1 commit

  • Fix a mutex_unlock() issue where before copy_from_user() is
    not called mutex_locked.

    Fixes: 4b1a29a7f542 ("error-injection: Support fault injection framework")
    Reported-by: Hulk Robot
    Signed-off-by: Luo Meng
    Signed-off-by: Masami Hiramatsu
    Signed-off-by: Alexei Starovoitov
    Acked-by: Masami Hiramatsu
    Link: https://lore.kernel.org/bpf/160570737118.263807.8358435412898356284.stgit@devnote2

    Luo Meng
     

03 Jun, 2019

1 commit


09 Apr, 2019

1 commit

  • %pF and %pf are functionally equivalent to %pS and %ps conversion
    specifiers. The former are deprecated, therefore switch the current users
    to use the preferred variant.

    The changes have been produced by the following command:

    git grep -l '%p[fF]' | grep -v '^\(tools\|Documentation\)/' | \
    while read i; do perl -i -pe 's/%pf/%ps/g; s/%pF/%pS/g;' $i; done

    And verifying the result.

    Link: http://lkml.kernel.org/r/20190325193229.23390-1-sakari.ailus@linux.intel.com
    Cc: Andy Shevchenko
    Cc: linux-arm-kernel@lists.infradead.org
    Cc: sparclinux@vger.kernel.org
    Cc: linux-um@lists.infradead.org
    Cc: xen-devel@lists.xenproject.org
    Cc: linux-acpi@vger.kernel.org
    Cc: linux-pm@vger.kernel.org
    Cc: drbd-dev@lists.linbit.com
    Cc: linux-block@vger.kernel.org
    Cc: linux-mmc@vger.kernel.org
    Cc: linux-nvdimm@lists.01.org
    Cc: linux-pci@vger.kernel.org
    Cc: linux-scsi@vger.kernel.org
    Cc: linux-btrfs@vger.kernel.org
    Cc: linux-f2fs-devel@lists.sourceforge.net
    Cc: linux-mm@kvack.org
    Cc: ceph-devel@vger.kernel.org
    Cc: netdev@vger.kernel.org
    Signed-off-by: Sakari Ailus
    Acked-by: David Sterba (for btrfs)
    Acked-by: Mike Rapoport (for mm/memblock.c)
    Acked-by: Bjorn Helgaas (for drivers/pci)
    Acked-by: Rafael J. Wysocki
    Signed-off-by: Petr Mladek

    Sakari Ailus
     

31 Oct, 2018

1 commit


21 Jun, 2018

1 commit

  • Clear current_kprobe and enable preemption in kprobe
    even if pre_handler returns !0.

    This simplifies function override using kprobes.

    Jprobe used to require to keep the preemption disabled and
    keep current_kprobe until it returned to original function
    entry. For this reason kprobe_int3_handler() and similar
    arch dependent kprobe handers checks pre_handler result
    and exit without enabling preemption if the result is !0.

    After removing the jprobe, Kprobes does not need to
    keep preempt disabled even if user handler returns !0
    anymore.

    But since the function override handler in error-inject
    and bpf is also returns !0 if it overrides a function,
    to balancing the preempt count, it enables preemption
    and reset current kprobe by itself.

    That is a bad design that is very buggy. This fixes
    such unbalanced preempt-count and current_kprobes setting
    in kprobes, bpf and error-inject.

    Note: for powerpc and x86, this removes all preempt_disable
    from kprobe_ftrace_handler because ftrace callbacks are
    called under preempt disabled.

    Signed-off-by: Masami Hiramatsu
    Acked-by: Thomas Gleixner
    Acked-by: Naveen N. Rao
    Cc: Alexei Starovoitov
    Cc: Ananth N Mavinakayanahalli
    Cc: Andrew Morton
    Cc: Benjamin Herrenschmidt
    Cc: Catalin Marinas
    Cc: David S. Miller
    Cc: Fenghua Yu
    Cc: Heiko Carstens
    Cc: James Hogan
    Cc: Josef Bacik
    Cc: Linus Torvalds
    Cc: Martin Schwidefsky
    Cc: Michael Ellerman
    Cc: Paul Mackerras
    Cc: Peter Zijlstra
    Cc: Ralf Baechle
    Cc: Rich Felker
    Cc: Russell King
    Cc: Steven Rostedt
    Cc: Tony Luck
    Cc: Vineet Gupta
    Cc: Will Deacon
    Cc: Yoshinori Sato
    Cc: linux-arch@vger.kernel.org
    Cc: linux-arm-kernel@lists.infradead.org
    Cc: linux-ia64@vger.kernel.org
    Cc: linux-mips@linux-mips.org
    Cc: linux-s390@vger.kernel.org
    Cc: linux-sh@vger.kernel.org
    Cc: linux-snps-arc@lists.infradead.org
    Cc: linuxppc-dev@lists.ozlabs.org
    Cc: sparclinux@vger.kernel.org
    Link: https://lore.kernel.org/lkml/152942494574.15209.12323837825873032258.stgit@devbox
    Signed-off-by: Ingo Molnar

    Masami Hiramatsu
     

13 Jun, 2018

1 commit

  • The kmalloc() function has a 2-factor argument form, kmalloc_array(). This
    patch replaces cases of:

    kmalloc(a * b, gfp)

    with:
    kmalloc_array(a * b, gfp)

    as well as handling cases of:

    kmalloc(a * b * c, gfp)

    with:

    kmalloc(array3_size(a, b, c), gfp)

    as it's slightly less ugly than:

    kmalloc_array(array_size(a, b), c, gfp)

    This does, however, attempt to ignore constant size factors like:

    kmalloc(4 * 1024, gfp)

    though any constants defined via macros get caught up in the conversion.

    Any factors with a sizeof() of "unsigned char", "char", and "u8" were
    dropped, since they're redundant.

    The tools/ directory was manually excluded, since it has its own
    implementation of kmalloc().

    The Coccinelle script used for this was:

    // Fix redundant parens around sizeof().
    @@
    type TYPE;
    expression THING, E;
    @@

    (
    kmalloc(
    - (sizeof(TYPE)) * E
    + sizeof(TYPE) * E
    , ...)
    |
    kmalloc(
    - (sizeof(THING)) * E
    + sizeof(THING) * E
    , ...)
    )

    // Drop single-byte sizes and redundant parens.
    @@
    expression COUNT;
    typedef u8;
    typedef __u8;
    @@

    (
    kmalloc(
    - sizeof(u8) * (COUNT)
    + COUNT
    , ...)
    |
    kmalloc(
    - sizeof(__u8) * (COUNT)
    + COUNT
    , ...)
    |
    kmalloc(
    - sizeof(char) * (COUNT)
    + COUNT
    , ...)
    |
    kmalloc(
    - sizeof(unsigned char) * (COUNT)
    + COUNT
    , ...)
    |
    kmalloc(
    - sizeof(u8) * COUNT
    + COUNT
    , ...)
    |
    kmalloc(
    - sizeof(__u8) * COUNT
    + COUNT
    , ...)
    |
    kmalloc(
    - sizeof(char) * COUNT
    + COUNT
    , ...)
    |
    kmalloc(
    - sizeof(unsigned char) * COUNT
    + COUNT
    , ...)
    )

    // 2-factor product with sizeof(type/expression) and identifier or constant.
    @@
    type TYPE;
    expression THING;
    identifier COUNT_ID;
    constant COUNT_CONST;
    @@

    (
    - kmalloc
    + kmalloc_array
    (
    - sizeof(TYPE) * (COUNT_ID)
    + COUNT_ID, sizeof(TYPE)
    , ...)
    |
    - kmalloc
    + kmalloc_array
    (
    - sizeof(TYPE) * COUNT_ID
    + COUNT_ID, sizeof(TYPE)
    , ...)
    |
    - kmalloc
    + kmalloc_array
    (
    - sizeof(TYPE) * (COUNT_CONST)
    + COUNT_CONST, sizeof(TYPE)
    , ...)
    |
    - kmalloc
    + kmalloc_array
    (
    - sizeof(TYPE) * COUNT_CONST
    + COUNT_CONST, sizeof(TYPE)
    , ...)
    |
    - kmalloc
    + kmalloc_array
    (
    - sizeof(THING) * (COUNT_ID)
    + COUNT_ID, sizeof(THING)
    , ...)
    |
    - kmalloc
    + kmalloc_array
    (
    - sizeof(THING) * COUNT_ID
    + COUNT_ID, sizeof(THING)
    , ...)
    |
    - kmalloc
    + kmalloc_array
    (
    - sizeof(THING) * (COUNT_CONST)
    + COUNT_CONST, sizeof(THING)
    , ...)
    |
    - kmalloc
    + kmalloc_array
    (
    - sizeof(THING) * COUNT_CONST
    + COUNT_CONST, sizeof(THING)
    , ...)
    )

    // 2-factor product, only identifiers.
    @@
    identifier SIZE, COUNT;
    @@

    - kmalloc
    + kmalloc_array
    (
    - SIZE * COUNT
    + COUNT, SIZE
    , ...)

    // 3-factor product with 1 sizeof(type) or sizeof(expression), with
    // redundant parens removed.
    @@
    expression THING;
    identifier STRIDE, COUNT;
    type TYPE;
    @@

    (
    kmalloc(
    - sizeof(TYPE) * (COUNT) * (STRIDE)
    + array3_size(COUNT, STRIDE, sizeof(TYPE))
    , ...)
    |
    kmalloc(
    - sizeof(TYPE) * (COUNT) * STRIDE
    + array3_size(COUNT, STRIDE, sizeof(TYPE))
    , ...)
    |
    kmalloc(
    - sizeof(TYPE) * COUNT * (STRIDE)
    + array3_size(COUNT, STRIDE, sizeof(TYPE))
    , ...)
    |
    kmalloc(
    - sizeof(TYPE) * COUNT * STRIDE
    + array3_size(COUNT, STRIDE, sizeof(TYPE))
    , ...)
    |
    kmalloc(
    - sizeof(THING) * (COUNT) * (STRIDE)
    + array3_size(COUNT, STRIDE, sizeof(THING))
    , ...)
    |
    kmalloc(
    - sizeof(THING) * (COUNT) * STRIDE
    + array3_size(COUNT, STRIDE, sizeof(THING))
    , ...)
    |
    kmalloc(
    - sizeof(THING) * COUNT * (STRIDE)
    + array3_size(COUNT, STRIDE, sizeof(THING))
    , ...)
    |
    kmalloc(
    - sizeof(THING) * COUNT * STRIDE
    + array3_size(COUNT, STRIDE, sizeof(THING))
    , ...)
    )

    // 3-factor product with 2 sizeof(variable), with redundant parens removed.
    @@
    expression THING1, THING2;
    identifier COUNT;
    type TYPE1, TYPE2;
    @@

    (
    kmalloc(
    - sizeof(TYPE1) * sizeof(TYPE2) * COUNT
    + array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2))
    , ...)
    |
    kmalloc(
    - sizeof(TYPE1) * sizeof(THING2) * (COUNT)
    + array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2))
    , ...)
    |
    kmalloc(
    - sizeof(THING1) * sizeof(THING2) * COUNT
    + array3_size(COUNT, sizeof(THING1), sizeof(THING2))
    , ...)
    |
    kmalloc(
    - sizeof(THING1) * sizeof(THING2) * (COUNT)
    + array3_size(COUNT, sizeof(THING1), sizeof(THING2))
    , ...)
    |
    kmalloc(
    - sizeof(TYPE1) * sizeof(THING2) * COUNT
    + array3_size(COUNT, sizeof(TYPE1), sizeof(THING2))
    , ...)
    |
    kmalloc(
    - sizeof(TYPE1) * sizeof(THING2) * (COUNT)
    + array3_size(COUNT, sizeof(TYPE1), sizeof(THING2))
    , ...)
    )

    // 3-factor product, only identifiers, with redundant parens removed.
    @@
    identifier STRIDE, SIZE, COUNT;
    @@

    (
    kmalloc(
    - (COUNT) * STRIDE * SIZE
    + array3_size(COUNT, STRIDE, SIZE)
    , ...)
    |
    kmalloc(
    - COUNT * (STRIDE) * SIZE
    + array3_size(COUNT, STRIDE, SIZE)
    , ...)
    |
    kmalloc(
    - COUNT * STRIDE * (SIZE)
    + array3_size(COUNT, STRIDE, SIZE)
    , ...)
    |
    kmalloc(
    - (COUNT) * (STRIDE) * SIZE
    + array3_size(COUNT, STRIDE, SIZE)
    , ...)
    |
    kmalloc(
    - COUNT * (STRIDE) * (SIZE)
    + array3_size(COUNT, STRIDE, SIZE)
    , ...)
    |
    kmalloc(
    - (COUNT) * STRIDE * (SIZE)
    + array3_size(COUNT, STRIDE, SIZE)
    , ...)
    |
    kmalloc(
    - (COUNT) * (STRIDE) * (SIZE)
    + array3_size(COUNT, STRIDE, SIZE)
    , ...)
    |
    kmalloc(
    - COUNT * STRIDE * SIZE
    + array3_size(COUNT, STRIDE, SIZE)
    , ...)
    )

    // Any remaining multi-factor products, first at least 3-factor products,
    // when they're not all constants...
    @@
    expression E1, E2, E3;
    constant C1, C2, C3;
    @@

    (
    kmalloc(C1 * C2 * C3, ...)
    |
    kmalloc(
    - (E1) * E2 * E3
    + array3_size(E1, E2, E3)
    , ...)
    |
    kmalloc(
    - (E1) * (E2) * E3
    + array3_size(E1, E2, E3)
    , ...)
    |
    kmalloc(
    - (E1) * (E2) * (E3)
    + array3_size(E1, E2, E3)
    , ...)
    |
    kmalloc(
    - E1 * E2 * E3
    + array3_size(E1, E2, E3)
    , ...)
    )

    // And then all remaining 2 factors products when they're not all constants,
    // keeping sizeof() as the second factor argument.
    @@
    expression THING, E1, E2;
    type TYPE;
    constant C1, C2, C3;
    @@

    (
    kmalloc(sizeof(THING) * C2, ...)
    |
    kmalloc(sizeof(TYPE) * C2, ...)
    |
    kmalloc(C1 * C2 * C3, ...)
    |
    kmalloc(C1 * C2, ...)
    |
    - kmalloc
    + kmalloc_array
    (
    - sizeof(TYPE) * (E2)
    + E2, sizeof(TYPE)
    , ...)
    |
    - kmalloc
    + kmalloc_array
    (
    - sizeof(TYPE) * E2
    + E2, sizeof(TYPE)
    , ...)
    |
    - kmalloc
    + kmalloc_array
    (
    - sizeof(THING) * (E2)
    + E2, sizeof(THING)
    , ...)
    |
    - kmalloc
    + kmalloc_array
    (
    - sizeof(THING) * E2
    + E2, sizeof(THING)
    , ...)
    |
    - kmalloc
    + kmalloc_array
    (
    - (E1) * E2
    + E1, E2
    , ...)
    |
    - kmalloc
    + kmalloc_array
    (
    - (E1) * (E2)
    + E1, E2
    , ...)
    |
    - kmalloc
    + kmalloc_array
    (
    - E1 * E2
    + E1, E2
    , ...)
    )

    Signed-off-by: Kees Cook

    Kees Cook
     

12 Mar, 2018

1 commit

  • Since the kprobe which was optimized by jump can not change
    the execution path, the kprobe for error-injection must not
    be optimized. To prohibit it, set a dummy post-handler as
    officially stated in Documentation/kprobes.txt.

    Fixes: 4b1a29a7f542 ("error-injection: Support fault injection framework")
    Signed-off-by: Masami Hiramatsu
    Signed-off-by: Daniel Borkmann

    Masami Hiramatsu
     

13 Jan, 2018

1 commit

  • Support in-kernel fault-injection framework via debugfs.
    This allows you to inject a conditional error to specified
    function using debugfs interfaces.

    Here is the result of test script described in
    Documentation/fault-injection/fault-injection.txt

    ===========
    # ./test_fail_function.sh
    1+0 records in
    1+0 records out
    1048576 bytes (1.0 MB, 1.0 MiB) copied, 0.0227404 s, 46.1 MB/s
    btrfs-progs v4.4
    See http://btrfs.wiki.kernel.org for more information.

    Label: (null)
    UUID: bfa96010-12e9-4360-aed0-42eec7af5798
    Node size: 16384
    Sector size: 4096
    Filesystem size: 1001.00MiB
    Block group profiles:
    Data: single 8.00MiB
    Metadata: DUP 58.00MiB
    System: DUP 12.00MiB
    SSD detected: no
    Incompat features: extref, skinny-metadata
    Number of devices: 1
    Devices:
    ID SIZE PATH
    1 1001.00MiB /dev/loop2

    mount: mount /dev/loop2 on /opt/tmpmnt failed: Cannot allocate memory
    SUCCESS!
    ===========

    Signed-off-by: Masami Hiramatsu
    Reviewed-by: Josef Bacik
    Signed-off-by: Alexei Starovoitov

    Masami Hiramatsu