src/ccache-win32/patches/0005-ccache-on-win32-crashes-sometimes.patch

   1 From 5e1ddeddca818e4f9785fb1d47c930df05e5dfcc Mon Sep 17 00:00:00 2001
   2 From: Pat Thoyts <patthoyts@users.sourceforge.net>
   3 Date: Wed, 15 May 2013 13:15:51 +0100
   4 Subject: [PATCH] ccache on win32 crashes sometimes
   5
   6 Compiling a more or less large project under Windows XP with ccache-2.4-
   7 win32 aborts with a crash dialog ("send problem report to microsoft" -
   8 dialog) in irregular intervals.
   9
  10 I could trace the problem to the x_realloc code, which looks like this:
  11
  12 /*
  13   this is like realloc() but dies if the malloc fails
  14 */
  15 void *x_realloc(void *ptr, size_t size)
  16 {
  17         void *p2;
  18         if (!ptr) return x_malloc(size);
  19         p2 = malloc(size);
  20         if (!p2) {
  21                 fatal("out of memory in x_realloc");
  22         }
  23         if (ptr) {
  24                 memcpy(p2, ptr, size);
  25                 free(ptr);
  26         }
  27         return p2;
  28 }
  29
  30 Suppose ptr points to a 100 bytes area of memory and you
  31 reallocate this to 1000000 bytes. Then this line
  32
  33                 memcpy(p2, ptr, size);
  34
  35 will copy 1000000 bytes of data from the old to the new
  36 location, which means that memcpy will read memory far
  37 outside the original allocated area.
  38
  39 [ccache-win32 issue #8]
  40
  41 Signed-off-by: Pat Thoyts <patthoyts@users.sourceforge.net>
  42 ---
  43  args.c    | 11 ++++++++---
  44  ccache.h  |  3 ++-
  45  cleanup.c |  6 +++++-
  46  util.c    |  4 ++--
  47  4 files changed, 17 insertions(+), 7 deletions(-)
  48
  49 diff --git a/args.c b/args.c
  50 index 31e5471..edbde7f 100644
  51 --- a/args.c
  52 +++ b/args.c
  53 @@ -26,7 +26,8 @@ ARGS *args_init(int init_argc, char **init_args)
  54         int i;
  55         args = (ARGS *)x_malloc(sizeof(ARGS));
  56         args->argc = 0;
  57 -       args->argv = (char **)x_malloc(sizeof(char *));
  58 +       args->argvSize = sizeof(char *);
  59 +       args->argv = (char **)x_malloc(args->argvSize);
  60         args->argv[0] = NULL;
  61         for (i=0;i<init_argc;i++) {
  62                 args_add(args, init_args[i]);
  63 @@ -37,7 +38,9 @@ ARGS *args_init(int init_argc, char **init_args)
  64
  65  void args_add(ARGS *args, const char *s)
  66  {
  67 -       args->argv = (char**)x_realloc(args->argv, (args->argc + 2) * sizeof(char *));
  68 +    size_t size = (args->argc + 2) * sizeof(char *);
  69 +       args->argv = (char**)x_realloc(args->argv, size, args->argvSize);
  70 +       args->argvSize = size;
  71         args->argv[args->argc] = x_strdup(s);
  72         args->argc++;
  73         args->argv[args->argc] = NULL;
  74 @@ -66,7 +69,9 @@ void args_remove_first(ARGS *args)
  75  /* add an argument into the front of the argument list */
  76  void args_add_prefix(ARGS *args, const char *s)
  77  {
  78 -       args->argv = (char**)x_realloc(args->argv, (args->argc + 2) * sizeof(char *));
  79 +    size_t size = (args->argc + 2) * sizeof(char *);
  80 +       args->argv = (char**)x_realloc(args->argv, size, args->argvSize);
  81 +       args->argvSize = size;
  82         memmove(&args->argv[1], &args->argv[0],
  83                 (args->argc+1) * sizeof(args->argv[0]));
  84         args->argv[0] = x_strdup(s);
  85 diff --git a/ccache.h b/ccache.h
  86 index d512e78..e65888d 100644
  87 --- a/ccache.h
  88 +++ b/ccache.h
  89 @@ -95,7 +95,7 @@ int copy_file(const char *src, const char *dest);
  90  int create_dir(const char *dir);
  91  void x_asprintf(char **ptr, const char *format, ...);
  92  char *x_strdup(const char *s);
  93 -void *x_realloc(void *ptr, size_t size);
  94 +void *x_realloc(void *ptr, size_t size, size_t oldSize);
  95  void *x_malloc(size_t size);
  96  void traverse(const char *dir, void (*fn)(const char *, struct stat *));
  97  char *str_basename(const char *s);
  98 @@ -143,6 +143,7 @@ char *find_executable(const char *name, const char *exclude_name);
  99  typedef struct {
 100         char **argv;
 101         int argc;
 102 +       size_t argvSize;
 103  } ARGS;
 104
 105
 106 diff --git a/cleanup.c b/cleanup.c
 107 index 9931228..1956e04 100644
 108 --- a/cleanup.c
 109 +++ b/cleanup.c
 110 @@ -49,6 +49,7 @@ static int files_compare(struct files **f1, struct files **f2)
 111  static void traverse_fn(const char *fname, struct stat *st)
 112  {
 113         char *p;
 114 +       unsigned oldAllocated;
 115
 116         if (!S_ISREG(st->st_mode)) return;
 117
 118 @@ -60,9 +61,11 @@ static void traverse_fn(const char *fname, struct stat *st)
 119         free(p);
 120
 121         if (num_files == allocated) {
 122 +           oldAllocated = allocated;
 123                 allocated = 10000 + num_files*2;
 124                 files = (struct files **)x_realloc(files,
 125 -                                                  sizeof(struct files *)*allocated);
 126 +                                                  sizeof(struct files *)*allocated,
 127 +                                                  sizeof(struct files *)*oldAllocated);
 128         }
 129
 130         files[num_files] = (struct files *)x_malloc(sizeof(struct files));
 131 @@ -111,6 +114,7 @@ void cleanup_dir(const char *dir, size_t maxfiles, size_t maxsize)
 132         files_threshold = maxfiles * LIMIT_MULTIPLE;
 133
 134         num_files = 0;
 135 +       allocated = 0;
 136         total_size = 0;
 137
 138         /* build a list of files */
 139 diff --git a/util.c b/util.c
 140 index 54fae89..531883d 100644
 141 --- a/util.c
 142 +++ b/util.c
 143 @@ -200,7 +200,7 @@ void *x_malloc(size_t size)
 144  /*
 145    this is like realloc() but dies if the malloc fails
 146  */
 147 -void *x_realloc(void *ptr, size_t size)
 148 +void *x_realloc(void *ptr, size_t size, size_t oldSize)
 149  {
 150         void *p2;
 151         if (!ptr) return x_malloc(size);
 152 @@ -209,7 +209,7 @@ void *x_realloc(void *ptr, size_t size)
 153                 fatal("out of memory in x_realloc");
 154         }
 155         if (ptr) {
 156 -               memcpy(p2, ptr, size);
 157 +               memcpy(p2, ptr, ((oldSize < size) ? oldSize : size));
 158                 free(ptr);
 159         }
 160         return p2;
 161 --
 162 1.8.1.msysgit.1
 163