1. 13 12月, 2017 3 次提交
    • J
      bpf: add a bpf_override_function helper · 9802d865
      Josef Bacik 提交于
      Error injection is sloppy and very ad-hoc.  BPF could fill this niche
      perfectly with it's kprobe functionality.  We could make sure errors are
      only triggered in specific call chains that we care about with very
      specific situations.  Accomplish this with the bpf_override_funciton
      helper.  This will modify the probe'd callers return value to the
      specified value and set the PC to an override function that simply
      returns, bypassing the originally probed function.  This gives us a nice
      clean way to implement systematic error injection for all of our code
      paths.
      Acked-by: NAlexei Starovoitov <ast@kernel.org>
      Acked-by: NIngo Molnar <mingo@kernel.org>
      Signed-off-by: NJosef Bacik <jbacik@fb.com>
      Signed-off-by: NAlexei Starovoitov <ast@kernel.org>
      9802d865
    • J
      add infrastructure for tagging functions as error injectable · 92ace999
      Josef Bacik 提交于
      Using BPF we can override kprob'ed functions and return arbitrary
      values.  Obviously this can be a bit unsafe, so make this feature opt-in
      for functions.  Simply tag a function with KPROBE_ERROR_INJECT_SYMBOL in
      order to give BPF access to that function for error injection purposes.
      Signed-off-by: NJosef Bacik <jbacik@fb.com>
      Acked-by: NIngo Molnar <mingo@kernel.org>
      Signed-off-by: NAlexei Starovoitov <ast@kernel.org>
      92ace999
    • Y
      bpf/tracing: allow user space to query prog array on the same tp · f371b304
      Yonghong Song 提交于
      Commit e87c6bc3 ("bpf: permit multiple bpf attachments
      for a single perf event") added support to attach multiple
      bpf programs to a single perf event.
      Although this provides flexibility, users may want to know
      what other bpf programs attached to the same tp interface.
      Besides getting visibility for the underlying bpf system,
      such information may also help consolidate multiple bpf programs,
      understand potential performance issues due to a large array,
      and debug (e.g., one bpf program which overwrites return code
      may impact subsequent program results).
      
      Commit 2541517c ("tracing, perf: Implement BPF programs
      attached to kprobes") utilized the existing perf ioctl
      interface and added the command PERF_EVENT_IOC_SET_BPF
      to attach a bpf program to a tracepoint. This patch adds a new
      ioctl command, given a perf event fd, to query the bpf program
      array attached to the same perf tracepoint event.
      
      The new uapi ioctl command:
        PERF_EVENT_IOC_QUERY_BPF
      
      The new uapi/linux/perf_event.h structure:
        struct perf_event_query_bpf {
             __u32	ids_len;
             __u32	prog_cnt;
             __u32	ids[0];
        };
      
      User space provides buffer "ids" for kernel to copy to.
      When returning from the kernel, the number of available
      programs in the array is set in "prog_cnt".
      
      The usage:
        struct perf_event_query_bpf *query =
          malloc(sizeof(*query) + sizeof(u32) * ids_len);
        query.ids_len = ids_len;
        err = ioctl(pmu_efd, PERF_EVENT_IOC_QUERY_BPF, query);
        if (err == 0) {
          /* query.prog_cnt is the number of available progs,
           * number of progs in ids: (ids_len == 0) ? 0 : query.prog_cnt
           */
        } else if (errno == ENOSPC) {
          /* query.ids_len number of progs copied,
           * query.prog_cnt is the number of available progs
           */
        } else {
            /* other errors */
        }
      Signed-off-by: NYonghong Song <yhs@fb.com>
      Acked-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
      Acked-by: NAlexei Starovoitov <ast@kernel.org>
      Signed-off-by: NAlexei Starovoitov <ast@kernel.org>
      f371b304
  2. 01 12月, 2017 7 次提交
  3. 30 11月, 2017 1 次提交
  4. 28 11月, 2017 2 次提交
  5. 24 11月, 2017 1 次提交
  6. 23 11月, 2017 5 次提交
    • A
      bpf: fix branch pruning logic · c131187d
      Alexei Starovoitov 提交于
      when the verifier detects that register contains a runtime constant
      and it's compared with another constant it will prune exploration
      of the branch that is guaranteed not to be taken at runtime.
      This is all correct, but malicious program may be constructed
      in such a way that it always has a constant comparison and
      the other branch is never taken under any conditions.
      In this case such path through the program will not be explored
      by the verifier. It won't be taken at run-time either, but since
      all instructions are JITed the malicious program may cause JITs
      to complain about using reserved fields, etc.
      To fix the issue we have to track the instructions explored by
      the verifier and sanitize instructions that are dead at run time
      with NOPs. We cannot reject such dead code, since llvm generates
      it for valid C code, since it doesn't do as much data flow
      analysis as the verifier does.
      
      Fixes: 17a52670 ("bpf: verifier (add verifier core)")
      Signed-off-by: NAlexei Starovoitov <ast@kernel.org>
      Acked-by: NDaniel Borkmann <daniel@iogearbox.net>
      Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>
      c131187d
    • G
      bpf: change bpf_perf_event_output arg5 type to ARG_CONST_SIZE_OR_ZERO · a60dd35d
      Gianluca Borello 提交于
      Commit 9fd29c08 ("bpf: improve verifier ARG_CONST_SIZE_OR_ZERO
      semantics") relaxed the treatment of ARG_CONST_SIZE_OR_ZERO due to the way
      the compiler generates optimized BPF code when checking boundaries of an
      argument from C code. A typical example of this optimized code can be
      generated using the bpf_perf_event_output helper when operating on variable
      memory:
      
      /* len is a generic scalar */
      if (len > 0 && len <= 0x7fff)
              bpf_perf_event_output(ctx, &perf_map, 0, buf, len);
      
      110: (79) r5 = *(u64 *)(r10 -40)
      111: (bf) r1 = r5
      112: (07) r1 += -1
      113: (25) if r1 > 0x7ffe goto pc+6
      114: (bf) r1 = r6
      115: (18) r2 = 0xffff94e5f166c200
      117: (b7) r3 = 0
      118: (bf) r4 = r7
      119: (85) call bpf_perf_event_output#25
      R5 min value is negative, either use unsigned or 'var &= const'
      
      With this code, the verifier loses track of the variable.
      
      Replacing arg5 with ARG_CONST_SIZE_OR_ZERO is thus desirable since it
      avoids this quite common case which leads to usability issues, and the
      compiler generates code that the verifier can more easily test:
      
      if (len <= 0x7fff)
              bpf_perf_event_output(ctx, &perf_map, 0, buf, len);
      
      or
      
      bpf_perf_event_output(ctx, &perf_map, 0, buf, len & 0x7fff);
      
      No changes to the bpf_perf_event_output helper are necessary since it can
      handle a case where size is 0, and an empty frame is pushed.
      Reported-by: NArnaldo Carvalho de Melo <acme@redhat.com>
      Signed-off-by: NGianluca Borello <g.borello@gmail.com>
      Acked-by: NAlexei Starovoitov <ast@kernel.org>
      Acked-by: NDaniel Borkmann <daniel@iogearbox.net>
      Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>
      a60dd35d
    • G
      bpf: change bpf_probe_read_str arg2 type to ARG_CONST_SIZE_OR_ZERO · 5c4e1201
      Gianluca Borello 提交于
      Commit 9fd29c08 ("bpf: improve verifier ARG_CONST_SIZE_OR_ZERO
      semantics") relaxed the treatment of ARG_CONST_SIZE_OR_ZERO due to the way
      the compiler generates optimized BPF code when checking boundaries of an
      argument from C code. A typical example of this optimized code can be
      generated using the bpf_probe_read_str helper when operating on variable
      memory:
      
      /* len is a generic scalar */
      if (len > 0 && len <= 0x7fff)
              bpf_probe_read_str(p, len, s);
      
      251: (79) r1 = *(u64 *)(r10 -88)
      252: (07) r1 += -1
      253: (25) if r1 > 0x7ffe goto pc-42
      254: (bf) r1 = r7
      255: (79) r2 = *(u64 *)(r10 -88)
      256: (bf) r8 = r4
      257: (85) call bpf_probe_read_str#45
      R2 min value is negative, either use unsigned or 'var &= const'
      
      With this code, the verifier loses track of the variable.
      
      Replacing arg2 with ARG_CONST_SIZE_OR_ZERO is thus desirable since it
      avoids this quite common case which leads to usability issues, and the
      compiler generates code that the verifier can more easily test:
      
      if (len <= 0x7fff)
              bpf_probe_read_str(p, len, s);
      
      or
      
      bpf_probe_read_str(p, len & 0x7fff, s);
      
      No changes to the bpf_probe_read_str helper are necessary since
      strncpy_from_unsafe itself immediately returns if the size passed is 0.
      Signed-off-by: NGianluca Borello <g.borello@gmail.com>
      Acked-by: NAlexei Starovoitov <ast@kernel.org>
      Acked-by: NDaniel Borkmann <daniel@iogearbox.net>
      Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>
      5c4e1201
    • G
      bpf: remove explicit handling of 0 for arg2 in bpf_probe_read · eb33f2cc
      Gianluca Borello 提交于
      Commit 9c019e2b ("bpf: change helper bpf_probe_read arg2 type to
      ARG_CONST_SIZE_OR_ZERO") changed arg2 type to ARG_CONST_SIZE_OR_ZERO to
      simplify writing bpf programs by taking advantage of the new semantics
      introduced for ARG_CONST_SIZE_OR_ZERO which allows <!NULL, 0> arguments.
      
      In order to prevent the helper from actually passing a NULL pointer to
      probe_kernel_read, which can happen when <NULL, 0> is passed to the helper,
      the commit also introduced an explicit check against size == 0.
      
      After the recent introduction of the ARG_PTR_TO_MEM_OR_NULL type,
      bpf_probe_read can not receive a pair of <NULL, 0> arguments anymore, thus
      the check is not needed anymore and can be removed, since probe_kernel_read
      can correctly handle a <!NULL, 0> call. This also fixes the semantics of
      the helper before it gets officially released and bpf programs start
      relying on this check.
      
      Fixes: 9c019e2b ("bpf: change helper bpf_probe_read arg2 type to ARG_CONST_SIZE_OR_ZERO")
      Signed-off-by: NGianluca Borello <g.borello@gmail.com>
      Acked-by: NAlexei Starovoitov <ast@kernel.org>
      Acked-by: NDaniel Borkmann <daniel@iogearbox.net>
      Acked-by: NYonghong Song <yhs@fb.com>
      Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>
      eb33f2cc
    • G
      bpf: introduce ARG_PTR_TO_MEM_OR_NULL · db1ac496
      Gianluca Borello 提交于
      With the current ARG_PTR_TO_MEM/ARG_PTR_TO_UNINIT_MEM semantics, an helper
      argument can be NULL when the next argument type is ARG_CONST_SIZE_OR_ZERO
      and the verifier can prove the value of this next argument is 0. However,
      most helpers are just interested in handling <!NULL, 0>, so forcing them to
      deal with <NULL, 0> makes the implementation of those helpers more
      complicated for no apparent benefits, requiring them to explicitly handle
      those corner cases with checks that bpf programs could start relying upon,
      preventing the possibility of removing them later.
      
      Solve this by making ARG_PTR_TO_MEM/ARG_PTR_TO_UNINIT_MEM never accept NULL
      even when ARG_CONST_SIZE_OR_ZERO is set, and introduce a new argument type
      ARG_PTR_TO_MEM_OR_NULL to explicitly deal with the NULL case.
      
      Currently, the only helper that needs this is bpf_csum_diff_proto(), so
      change arg1 and arg3 to this new type as well.
      
      Also add a new battery of tests that explicitly test the
      !ARG_PTR_TO_MEM_OR_NULL combination: all the current ones testing the
      various <NULL, 0> variations are focused on bpf_csum_diff, so cover also
      other helpers.
      Signed-off-by: NGianluca Borello <g.borello@gmail.com>
      Acked-by: NAlexei Starovoitov <ast@kernel.org>
      Acked-by: NDaniel Borkmann <daniel@iogearbox.net>
      Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>
      db1ac496
  7. 22 11月, 2017 7 次提交
    • K
      treewide: Remove TIMER_FUNC_TYPE and TIMER_DATA_TYPE casts · 841b86f3
      Kees Cook 提交于
      With all callbacks converted, and the timer callback prototype
      switched over, the TIMER_FUNC_TYPE cast is no longer needed,
      so remove it. Conversion was done with the following scripts:
      
          perl -pi -e 's|\(TIMER_FUNC_TYPE\)||g' \
              $(git grep TIMER_FUNC_TYPE | cut -d: -f1 | sort -u)
      
          perl -pi -e 's|\(TIMER_DATA_TYPE\)||g' \
              $(git grep TIMER_DATA_TYPE | cut -d: -f1 | sort -u)
      
      The now unused macros are also dropped from include/linux/timer.h.
      Signed-off-by: NKees Cook <keescook@chromium.org>
      841b86f3
    • K
      timer: Pass function down to initialization routines · 188665b2
      Kees Cook 提交于
      In preparation for removing more macros, pass the function down to the
      initialization routines instead of doing it in macros.
      
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: John Stultz <john.stultz@linaro.org>
      Cc: Stephen Boyd <sboyd@codeaurora.org>
      Signed-off-by: NKees Cook <keescook@chromium.org>
      188665b2
    • K
      timer: Switch callback prototype to take struct timer_list * argument · 354b46b1
      Kees Cook 提交于
      Since all callbacks have been converted, we can switch the core
      prototype to "struct timer_list *" now too.
      
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: John Stultz <john.stultz@linaro.org>
      Cc: Stephen Boyd <sboyd@codeaurora.org>
      Signed-off-by: NKees Cook <keescook@chromium.org>
      354b46b1
    • K
      timer: Pass timer_list pointer to callbacks unconditionally · c1eba5bc
      Kees Cook 提交于
      Now that all timer callbacks are already taking their struct timer_list
      pointer as the callback argument, just do this unconditionally and remove
      the .data field.
      
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: John Stultz <john.stultz@linaro.org>
      Cc: Stephen Boyd <sboyd@codeaurora.org>
      Signed-off-by: NKees Cook <keescook@chromium.org>
      c1eba5bc
    • K
      treewide: setup_timer() -> timer_setup() · e99e88a9
      Kees Cook 提交于
      This converts all remaining cases of the old setup_timer() API into using
      timer_setup(), where the callback argument is the structure already
      holding the struct timer_list. These should have no behavioral changes,
      since they just change which pointer is passed into the callback with
      the same available pointers after conversion. It handles the following
      examples, in addition to some other variations.
      
      Casting from unsigned long:
      
          void my_callback(unsigned long data)
          {
              struct something *ptr = (struct something *)data;
          ...
          }
          ...
          setup_timer(&ptr->my_timer, my_callback, ptr);
      
      and forced object casts:
      
          void my_callback(struct something *ptr)
          {
          ...
          }
          ...
          setup_timer(&ptr->my_timer, my_callback, (unsigned long)ptr);
      
      become:
      
          void my_callback(struct timer_list *t)
          {
              struct something *ptr = from_timer(ptr, t, my_timer);
          ...
          }
          ...
          timer_setup(&ptr->my_timer, my_callback, 0);
      
      Direct function assignments:
      
          void my_callback(unsigned long data)
          {
              struct something *ptr = (struct something *)data;
          ...
          }
          ...
          ptr->my_timer.function = my_callback;
      
      have a temporary cast added, along with converting the args:
      
          void my_callback(struct timer_list *t)
          {
              struct something *ptr = from_timer(ptr, t, my_timer);
          ...
          }
          ...
          ptr->my_timer.function = (TIMER_FUNC_TYPE)my_callback;
      
      And finally, callbacks without a data assignment:
      
          void my_callback(unsigned long data)
          {
          ...
          }
          ...
          setup_timer(&ptr->my_timer, my_callback, 0);
      
      have their argument renamed to verify they're unused during conversion:
      
          void my_callback(struct timer_list *unused)
          {
          ...
          }
          ...
          timer_setup(&ptr->my_timer, my_callback, 0);
      
      The conversion is done with the following Coccinelle script:
      
      spatch --very-quiet --all-includes --include-headers \
      	-I ./arch/x86/include -I ./arch/x86/include/generated \
      	-I ./include -I ./arch/x86/include/uapi \
      	-I ./arch/x86/include/generated/uapi -I ./include/uapi \
      	-I ./include/generated/uapi --include ./include/linux/kconfig.h \
      	--dir . \
      	--cocci-file ~/src/data/timer_setup.cocci
      
      @fix_address_of@
      expression e;
      @@
      
       setup_timer(
      -&(e)
      +&e
       , ...)
      
      // Update any raw setup_timer() usages that have a NULL callback, but
      // would otherwise match change_timer_function_usage, since the latter
      // will update all function assignments done in the face of a NULL
      // function initialization in setup_timer().
      @change_timer_function_usage_NULL@
      expression _E;
      identifier _timer;
      type _cast_data;
      @@
      
      (
      -setup_timer(&_E->_timer, NULL, _E);
      +timer_setup(&_E->_timer, NULL, 0);
      |
      -setup_timer(&_E->_timer, NULL, (_cast_data)_E);
      +timer_setup(&_E->_timer, NULL, 0);
      |
      -setup_timer(&_E._timer, NULL, &_E);
      +timer_setup(&_E._timer, NULL, 0);
      |
      -setup_timer(&_E._timer, NULL, (_cast_data)&_E);
      +timer_setup(&_E._timer, NULL, 0);
      )
      
      @change_timer_function_usage@
      expression _E;
      identifier _timer;
      struct timer_list _stl;
      identifier _callback;
      type _cast_func, _cast_data;
      @@
      
      (
      -setup_timer(&_E->_timer, _callback, _E);
      +timer_setup(&_E->_timer, _callback, 0);
      |
      -setup_timer(&_E->_timer, &_callback, _E);
      +timer_setup(&_E->_timer, _callback, 0);
      |
      -setup_timer(&_E->_timer, _callback, (_cast_data)_E);
      +timer_setup(&_E->_timer, _callback, 0);
      |
      -setup_timer(&_E->_timer, &_callback, (_cast_data)_E);
      +timer_setup(&_E->_timer, _callback, 0);
      |
      -setup_timer(&_E->_timer, (_cast_func)_callback, _E);
      +timer_setup(&_E->_timer, _callback, 0);
      |
      -setup_timer(&_E->_timer, (_cast_func)&_callback, _E);
      +timer_setup(&_E->_timer, _callback, 0);
      |
      -setup_timer(&_E->_timer, (_cast_func)_callback, (_cast_data)_E);
      +timer_setup(&_E->_timer, _callback, 0);
      |
      -setup_timer(&_E->_timer, (_cast_func)&_callback, (_cast_data)_E);
      +timer_setup(&_E->_timer, _callback, 0);
      |
      -setup_timer(&_E._timer, _callback, (_cast_data)_E);
      +timer_setup(&_E._timer, _callback, 0);
      |
      -setup_timer(&_E._timer, _callback, (_cast_data)&_E);
      +timer_setup(&_E._timer, _callback, 0);
      |
      -setup_timer(&_E._timer, &_callback, (_cast_data)_E);
      +timer_setup(&_E._timer, _callback, 0);
      |
      -setup_timer(&_E._timer, &_callback, (_cast_data)&_E);
      +timer_setup(&_E._timer, _callback, 0);
      |
      -setup_timer(&_E._timer, (_cast_func)_callback, (_cast_data)_E);
      +timer_setup(&_E._timer, _callback, 0);
      |
      -setup_timer(&_E._timer, (_cast_func)_callback, (_cast_data)&_E);
      +timer_setup(&_E._timer, _callback, 0);
      |
      -setup_timer(&_E._timer, (_cast_func)&_callback, (_cast_data)_E);
      +timer_setup(&_E._timer, _callback, 0);
      |
      -setup_timer(&_E._timer, (_cast_func)&_callback, (_cast_data)&_E);
      +timer_setup(&_E._timer, _callback, 0);
      |
       _E->_timer@_stl.function = _callback;
      |
       _E->_timer@_stl.function = &_callback;
      |
       _E->_timer@_stl.function = (_cast_func)_callback;
      |
       _E->_timer@_stl.function = (_cast_func)&_callback;
      |
       _E._timer@_stl.function = _callback;
      |
       _E._timer@_stl.function = &_callback;
      |
       _E._timer@_stl.function = (_cast_func)_callback;
      |
       _E._timer@_stl.function = (_cast_func)&_callback;
      )
      
      // callback(unsigned long arg)
      @change_callback_handle_cast
       depends on change_timer_function_usage@
      identifier change_timer_function_usage._callback;
      identifier change_timer_function_usage._timer;
      type _origtype;
      identifier _origarg;
      type _handletype;
      identifier _handle;
      @@
      
       void _callback(
      -_origtype _origarg
      +struct timer_list *t
       )
       {
      (
      	... when != _origarg
      	_handletype *_handle =
      -(_handletype *)_origarg;
      +from_timer(_handle, t, _timer);
      	... when != _origarg
      |
      	... when != _origarg
      	_handletype *_handle =
      -(void *)_origarg;
      +from_timer(_handle, t, _timer);
      	... when != _origarg
      |
      	... when != _origarg
      	_handletype *_handle;
      	... when != _handle
      	_handle =
      -(_handletype *)_origarg;
      +from_timer(_handle, t, _timer);
      	... when != _origarg
      |
      	... when != _origarg
      	_handletype *_handle;
      	... when != _handle
      	_handle =
      -(void *)_origarg;
      +from_timer(_handle, t, _timer);
      	... when != _origarg
      )
       }
      
      // callback(unsigned long arg) without existing variable
      @change_callback_handle_cast_no_arg
       depends on change_timer_function_usage &&
                           !change_callback_handle_cast@
      identifier change_timer_function_usage._callback;
      identifier change_timer_function_usage._timer;
      type _origtype;
      identifier _origarg;
      type _handletype;
      @@
      
       void _callback(
      -_origtype _origarg
      +struct timer_list *t
       )
       {
      +	_handletype *_origarg = from_timer(_origarg, t, _timer);
      +
      	... when != _origarg
      -	(_handletype *)_origarg
      +	_origarg
      	... when != _origarg
       }
      
      // Avoid already converted callbacks.
      @match_callback_converted
       depends on change_timer_function_usage &&
                  !change_callback_handle_cast &&
      	    !change_callback_handle_cast_no_arg@
      identifier change_timer_function_usage._callback;
      identifier t;
      @@
      
       void _callback(struct timer_list *t)
       { ... }
      
      // callback(struct something *handle)
      @change_callback_handle_arg
       depends on change_timer_function_usage &&
      	    !match_callback_converted &&
                  !change_callback_handle_cast &&
                  !change_callback_handle_cast_no_arg@
      identifier change_timer_function_usage._callback;
      identifier change_timer_function_usage._timer;
      type _handletype;
      identifier _handle;
      @@
      
       void _callback(
      -_handletype *_handle
      +struct timer_list *t
       )
       {
      +	_handletype *_handle = from_timer(_handle, t, _timer);
      	...
       }
      
      // If change_callback_handle_arg ran on an empty function, remove
      // the added handler.
      @unchange_callback_handle_arg
       depends on change_timer_function_usage &&
      	    change_callback_handle_arg@
      identifier change_timer_function_usage._callback;
      identifier change_timer_function_usage._timer;
      type _handletype;
      identifier _handle;
      identifier t;
      @@
      
       void _callback(struct timer_list *t)
       {
      -	_handletype *_handle = from_timer(_handle, t, _timer);
       }
      
      // We only want to refactor the setup_timer() data argument if we've found
      // the matching callback. This undoes changes in change_timer_function_usage.
      @unchange_timer_function_usage
       depends on change_timer_function_usage &&
                  !change_callback_handle_cast &&
                  !change_callback_handle_cast_no_arg &&
      	    !change_callback_handle_arg@
      expression change_timer_function_usage._E;
      identifier change_timer_function_usage._timer;
      identifier change_timer_function_usage._callback;
      type change_timer_function_usage._cast_data;
      @@
      
      (
      -timer_setup(&_E->_timer, _callback, 0);
      +setup_timer(&_E->_timer, _callback, (_cast_data)_E);
      |
      -timer_setup(&_E._timer, _callback, 0);
      +setup_timer(&_E._timer, _callback, (_cast_data)&_E);
      )
      
      // If we fixed a callback from a .function assignment, fix the
      // assignment cast now.
      @change_timer_function_assignment
       depends on change_timer_function_usage &&
                  (change_callback_handle_cast ||
                   change_callback_handle_cast_no_arg ||
                   change_callback_handle_arg)@
      expression change_timer_function_usage._E;
      identifier change_timer_function_usage._timer;
      identifier change_timer_function_usage._callback;
      type _cast_func;
      typedef TIMER_FUNC_TYPE;
      @@
      
      (
       _E->_timer.function =
      -_callback
      +(TIMER_FUNC_TYPE)_callback
       ;
      |
       _E->_timer.function =
      -&_callback
      +(TIMER_FUNC_TYPE)_callback
       ;
      |
       _E->_timer.function =
      -(_cast_func)_callback;
      +(TIMER_FUNC_TYPE)_callback
       ;
      |
       _E->_timer.function =
      -(_cast_func)&_callback
      +(TIMER_FUNC_TYPE)_callback
       ;
      |
       _E._timer.function =
      -_callback
      +(TIMER_FUNC_TYPE)_callback
       ;
      |
       _E._timer.function =
      -&_callback;
      +(TIMER_FUNC_TYPE)_callback
       ;
      |
       _E._timer.function =
      -(_cast_func)_callback
      +(TIMER_FUNC_TYPE)_callback
       ;
      |
       _E._timer.function =
      -(_cast_func)&_callback
      +(TIMER_FUNC_TYPE)_callback
       ;
      )
      
      // Sometimes timer functions are called directly. Replace matched args.
      @change_timer_function_calls
       depends on change_timer_function_usage &&
                  (change_callback_handle_cast ||
                   change_callback_handle_cast_no_arg ||
                   change_callback_handle_arg)@
      expression _E;
      identifier change_timer_function_usage._timer;
      identifier change_timer_function_usage._callback;
      type _cast_data;
      @@
      
       _callback(
      (
      -(_cast_data)_E
      +&_E->_timer
      |
      -(_cast_data)&_E
      +&_E._timer
      |
      -_E
      +&_E->_timer
      )
       )
      
      // If a timer has been configured without a data argument, it can be
      // converted without regard to the callback argument, since it is unused.
      @match_timer_function_unused_data@
      expression _E;
      identifier _timer;
      identifier _callback;
      @@
      
      (
      -setup_timer(&_E->_timer, _callback, 0);
      +timer_setup(&_E->_timer, _callback, 0);
      |
      -setup_timer(&_E->_timer, _callback, 0L);
      +timer_setup(&_E->_timer, _callback, 0);
      |
      -setup_timer(&_E->_timer, _callback, 0UL);
      +timer_setup(&_E->_timer, _callback, 0);
      |
      -setup_timer(&_E._timer, _callback, 0);
      +timer_setup(&_E._timer, _callback, 0);
      |
      -setup_timer(&_E._timer, _callback, 0L);
      +timer_setup(&_E._timer, _callback, 0);
      |
      -setup_timer(&_E._timer, _callback, 0UL);
      +timer_setup(&_E._timer, _callback, 0);
      |
      -setup_timer(&_timer, _callback, 0);
      +timer_setup(&_timer, _callback, 0);
      |
      -setup_timer(&_timer, _callback, 0L);
      +timer_setup(&_timer, _callback, 0);
      |
      -setup_timer(&_timer, _callback, 0UL);
      +timer_setup(&_timer, _callback, 0);
      |
      -setup_timer(_timer, _callback, 0);
      +timer_setup(_timer, _callback, 0);
      |
      -setup_timer(_timer, _callback, 0L);
      +timer_setup(_timer, _callback, 0);
      |
      -setup_timer(_timer, _callback, 0UL);
      +timer_setup(_timer, _callback, 0);
      )
      
      @change_callback_unused_data
       depends on match_timer_function_unused_data@
      identifier match_timer_function_unused_data._callback;
      type _origtype;
      identifier _origarg;
      @@
      
       void _callback(
      -_origtype _origarg
      +struct timer_list *unused
       )
       {
      	... when != _origarg
       }
      Signed-off-by: NKees Cook <keescook@chromium.org>
      e99e88a9
    • K
      treewide: init_timer() -> setup_timer() · b9eaf187
      Kees Cook 提交于
      This mechanically converts all remaining cases of ancient open-coded timer
      setup with the old setup_timer() API, which is the first step in timer
      conversions. This has no behavioral changes, since it ultimately just
      changes the order of assignment to fields of struct timer_list when
      finding variations of:
      
          init_timer(&t);
          f.function = timer_callback;
          t.data = timer_callback_arg;
      
      to be converted into:
      
          setup_timer(&t, timer_callback, timer_callback_arg);
      
      The conversion is done with the following Coccinelle script, which
      is an improved version of scripts/cocci/api/setup_timer.cocci, in the
      following ways:
       - assignments-before-init_timer() cases
       - limit the .data case removal to the specific struct timer_list instance
       - handling calls by dereference (timer->field vs timer.field)
      
      spatch --very-quiet --all-includes --include-headers \
      	-I ./arch/x86/include -I ./arch/x86/include/generated \
      	-I ./include -I ./arch/x86/include/uapi \
      	-I ./arch/x86/include/generated/uapi -I ./include/uapi \
      	-I ./include/generated/uapi --include ./include/linux/kconfig.h \
      	--dir . \
      	--cocci-file ~/src/data/setup_timer.cocci
      
      @fix_address_of@
      expression e;
      @@
      
       init_timer(
      -&(e)
      +&e
       , ...)
      
      // Match the common cases first to avoid Coccinelle parsing loops with
      // "... when" clauses.
      
      @match_immediate_function_data_after_init_timer@
      expression e, func, da;
      @@
      
      -init_timer
      +setup_timer
       ( \(&e\|e\)
      +, func, da
       );
      (
      -\(e.function\|e->function\) = func;
      -\(e.data\|e->data\) = da;
      |
      -\(e.data\|e->data\) = da;
      -\(e.function\|e->function\) = func;
      )
      
      @match_immediate_function_data_before_init_timer@
      expression e, func, da;
      @@
      
      (
      -\(e.function\|e->function\) = func;
      -\(e.data\|e->data\) = da;
      |
      -\(e.data\|e->data\) = da;
      -\(e.function\|e->function\) = func;
      )
      -init_timer
      +setup_timer
       ( \(&e\|e\)
      +, func, da
       );
      
      @match_function_and_data_after_init_timer@
      expression e, e2, e3, e4, e5, func, da;
      @@
      
      -init_timer
      +setup_timer
       ( \(&e\|e\)
      +, func, da
       );
       ... when != func = e2
           when != da = e3
      (
      -e.function = func;
      ... when != da = e4
      -e.data = da;
      |
      -e->function = func;
      ... when != da = e4
      -e->data = da;
      |
      -e.data = da;
      ... when != func = e5
      -e.function = func;
      |
      -e->data = da;
      ... when != func = e5
      -e->function = func;
      )
      
      @match_function_and_data_before_init_timer@
      expression e, e2, e3, e4, e5, func, da;
      @@
      (
      -e.function = func;
      ... when != da = e4
      -e.data = da;
      |
      -e->function = func;
      ... when != da = e4
      -e->data = da;
      |
      -e.data = da;
      ... when != func = e5
      -e.function = func;
      |
      -e->data = da;
      ... when != func = e5
      -e->function = func;
      )
      ... when != func = e2
          when != da = e3
      -init_timer
      +setup_timer
       ( \(&e\|e\)
      +, func, da
       );
      
      @r1 exists@
      expression t;
      identifier f;
      position p;
      @@
      
      f(...) { ... when any
        init_timer@p(\(&t\|t\))
        ... when any
      }
      
      @r2 exists@
      expression r1.t;
      identifier g != r1.f;
      expression e8;
      @@
      
      g(...) { ... when any
        \(t.data\|t->data\) = e8
        ... when any
      }
      
      // It is dangerous to use setup_timer if data field is initialized
      // in another function.
      @script:python depends on r2@
      p << r1.p;
      @@
      
      cocci.include_match(False)
      
      @r3@
      expression r1.t, func, e7;
      position r1.p;
      @@
      
      (
      -init_timer@p(&t);
      +setup_timer(&t, func, 0UL);
      ... when != func = e7
      -t.function = func;
      |
      -t.function = func;
      ... when != func = e7
      -init_timer@p(&t);
      +setup_timer(&t, func, 0UL);
      |
      -init_timer@p(t);
      +setup_timer(t, func, 0UL);
      ... when != func = e7
      -t->function = func;
      |
      -t->function = func;
      ... when != func = e7
      -init_timer@p(t);
      +setup_timer(t, func, 0UL);
      )
      Signed-off-by: NKees Cook <keescook@chromium.org>
      b9eaf187
    • K
      treewide: Switch DEFINE_TIMER callbacks to struct timer_list * · 24ed960a
      Kees Cook 提交于
      This changes all DEFINE_TIMER() callbacks to use a struct timer_list
      pointer instead of unsigned long. Since the data argument has already been
      removed, none of these callbacks are using their argument currently, so
      this renames the argument to "unused".
      
      Done using the following semantic patch:
      
      @match_define_timer@
      declarer name DEFINE_TIMER;
      identifier _timer, _callback;
      @@
      
       DEFINE_TIMER(_timer, _callback);
      
      @change_callback depends on match_define_timer@
      identifier match_define_timer._callback;
      type _origtype;
      identifier _origarg;
      @@
      
       void
      -_callback(_origtype _origarg)
      +_callback(struct timer_list *unused)
       { ... }
      Signed-off-by: NKees Cook <keescook@chromium.org>
      24ed960a
  8. 21 11月, 2017 7 次提交
  9. 20 11月, 2017 1 次提交
  10. 18 11月, 2017 6 次提交