scripts/coccinelle/misc/badty.cocci

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /// Correct the size argument to alloc functions
   3 ///
   4 //# This makes an effort to find cases where the argument to sizeof is wrong
   5 //# in memory allocation functions by checking the type of the allocated memory
   6 //# when it is a double pointer and ensuring the sizeof argument takes a pointer
   7 //# to the the memory being allocated. There are false positives in cases the
   8 //# sizeof argument is not used in constructing the return value. The result
   9 //# may need some reformatting.
  10 //
  11 // Confidence: Moderate
  12 // Copyright: (C) 2014 Himangi Saraogi.
  13 // Comments:
  14 // Options:
  15
  16 virtual patch
  17 virtual context
  18 virtual org
  19 virtual report
  20
  21 //----------------------------------------------------------
  22 //  For context mode
  23 //----------------------------------------------------------
  24
  25 @depends on context disable sizeof_type_expr@
  26 type T;
  27 T **x;
  28 @@
  29
  30   x =
  31   <+...sizeof(
  32 * T
  33   )...+>
  34
  35 //----------------------------------------------------------
  36 //  For patch mode
  37 //----------------------------------------------------------
  38
  39 @depends on patch disable sizeof_type_expr@
  40 type T;
  41 T **x;
  42 @@
  43
  44   x =
  45   <+...sizeof(
  46 - T
  47 + *x
  48   )...+>
  49
  50 //----------------------------------------------------------
  51 //  For org and report mode
  52 //----------------------------------------------------------
  53
  54 @r depends on (org || report) disable sizeof_type_expr@
  55 type T;
  56 T **x;
  57 position p;
  58 @@
  59
  60   x =
  61   <+...sizeof(
  62   T@p
  63   )...+>
  64
  65 @script:python depends on org@
  66 p << r.p;
  67 @@
  68
  69 coccilib.org.print_todo(p[0], "WARNING sizeof argument should be pointer type, not structure type")
  70
  71 @script:python depends on report@
  72 p << r.p;
  73 @@
  74
  75 msg="WARNING: Use correct pointer type argument for sizeof"
  76 coccilib.report.print_report(p[0], msg)
  77