Re: [PATCH v8 4/5] Use the .ACCESS_WITH_SIZE in bound sanitizer.

2024-04-11 Thread Qing Zhao 
Sid,

Thanks a lot for the review.


> On Apr 10, 2024, at 17:46, Siddhesh Poyarekar  wrote:
> 
> On 2024-03-29 12:07, Qing Zhao wrote:
>> gcc/c-family/ChangeLog:
>>  * c-ubsan.cc (get_bound_from_access_with_size): New function.
>>  (ubsan_instrument_bounds): Handle call to .ACCESS_WITH_SIZE.
>> gcc/testsuite/ChangeLog:
>>  * gcc.dg/ubsan/flex-array-counted-by-bounds-2.c: New test.
>>  * gcc.dg/ubsan/flex-array-counted-by-bounds-3.c: New test.
>>  * gcc.dg/ubsan/flex-array-counted-by-bounds-4.c: New test.
>>  * gcc.dg/ubsan/flex-array-counted-by-bounds.c: New test.
>> ---
> 
> This version looks fine to me for stage 1, but I'm not a maintainer so you'll 
> need an ack from one to commit.

This patch is purely C FE changes. Joseph already approved it.

thanks.

Qing
> 
> Thanks,
> Sid
> 
>>  gcc/c-family/c-ubsan.cc   | 42 +
>>  .../ubsan/flex-array-counted-by-bounds-2.c| 45 ++
>>  .../ubsan/flex-array-counted-by-bounds-3.c| 34 ++
>>  .../ubsan/flex-array-counted-by-bounds-4.c| 34 ++
>>  .../ubsan/flex-array-counted-by-bounds.c  | 46 +++
>>  5 files changed, 201 insertions(+)
>>  create mode 100644 
>> gcc/testsuite/gcc.dg/ubsan/flex-array-counted-by-bounds-2.c
>>  create mode 100644 
>> gcc/testsuite/gcc.dg/ubsan/flex-array-counted-by-bounds-3.c
>>  create mode 100644 
>> gcc/testsuite/gcc.dg/ubsan/flex-array-counted-by-bounds-4.c
>>  create mode 100644 gcc/testsuite/gcc.dg/ubsan/flex-array-counted-by-bounds.c
>> diff --git a/gcc/c-family/c-ubsan.cc b/gcc/c-family/c-ubsan.cc
>> index 940982819ddf..7cd3c6aa5b88 100644
>> --- a/gcc/c-family/c-ubsan.cc
>> +++ b/gcc/c-family/c-ubsan.cc
>> @@ -376,6 +376,40 @@ ubsan_instrument_return (location_t loc)
>>return build_call_expr_loc (loc, t, 1, build_fold_addr_expr_loc (loc, 
>> data));
>>  }
>>  +/* Get the tree that represented the number of counted_by, i.e, the maximum
>> +   number of the elements of the object that the call to .ACCESS_WITH_SIZE
>> +   points to, this number will be the bound of the corresponding array.  */
>> +static tree
>> +get_bound_from_access_with_size (tree call)
>> +{
>> +  if (!is_access_with_size_p (call))
>> +return NULL_TREE;
>> +
>> +  tree ref_to_size = CALL_EXPR_ARG (call, 1);
>> +  unsigned int class_of_size = TREE_INT_CST_LOW (CALL_EXPR_ARG (call, 2));
>> +  tree type = TREE_TYPE (CALL_EXPR_ARG (call, 3));
>> +  tree size = fold_build2 (MEM_REF, type, unshare_expr (ref_to_size),
>> +   build_int_cst (ptr_type_node, 0));
>> +  /* If size is negative value, treat it as zero.  */
>> +  if (!TYPE_UNSIGNED (type))
>> +  {
>> +tree cond = fold_build2 (LT_EXPR, boolean_type_node,
>> + unshare_expr (size), build_zero_cst (type));
>> +size = fold_build3 (COND_EXPR, type, cond,
>> +build_zero_cst (type), size);
>> +  }
>> +
>> +  /* Only when class_of_size is 1, i.e, the number of the elements of
>> + the object type, return the size.  */
>> +  if (class_of_size != 1)
>> +return NULL_TREE;
>> +  else
>> +size = fold_convert (sizetype, size);
>> +
>> +  return size;
>> +}
>> +
>> +
>>  /* Instrument array bounds for ARRAY_REFs.  We create special builtin,
>> that gets expanded in the sanopt pass, and make an array dimension
>> of it.  ARRAY is the array, *INDEX is an index to the array.
>> @@ -401,6 +435,14 @@ ubsan_instrument_bounds (location_t loc, tree array, 
>> tree *index,
>>&& COMPLETE_TYPE_P (type)
>>&& integer_zerop (TYPE_SIZE (type)))
>>  bound = build_int_cst (TREE_TYPE (TYPE_MIN_VALUE (domain)), -1);
>> +  else if (INDIRECT_REF_P (array)
>> +   && is_access_with_size_p ((TREE_OPERAND (array, 0
>> +{
>> +  bound = get_bound_from_access_with_size ((TREE_OPERAND (array, 0)));
>> +  bound = fold_build2 (MINUS_EXPR, TREE_TYPE (bound),
>> +   bound,
>> +   build_int_cst (TREE_TYPE (bound), 1));
>> +}
>>else
>>  return NULL_TREE;
>>  }
>> diff --git a/gcc/testsuite/gcc.dg/ubsan/flex-array-counted-by-bounds-2.c 
>> b/gcc/testsuite/gcc.dg/ubsan/flex-array-counted-by-bounds-2.c
>> new file mode 100644
>> index ..b503320628d2
>> --- /dev/null
>> +++ b/gcc/testsuite/gcc.dg/ubsan/flex-array-counted-by-bounds-2.c
>> @@ -0,0 +1,45 @@
>> +/* Test the attribute counted_by and its usage in
>> +   bounds sanitizer combined with VLA.  */
>> +/* { dg-do run } */
>> +/* { dg-options "-fsanitize=bounds" } */
>> +/* { dg-output "index 11 out of bounds for type 'int 
>> \\\[\\\*\\\]\\\[\\\*\\\]'\[^\n\r]*(\n|\r\n|\r)" } */
>> +/* { dg-output "\[^\n\r]*index 20 out of bounds for type 'int 
>> \\\[\\\*\\\]\\\[\\\*\\\]\\\[\\\*\\\]'\[^\n\r]*(\n|\r\n|\r)" } */
>> +/* { dg-output "\[^\n\r]*index 11 out of bounds for type 'int 
>> \\\[\\\*\\\]\\\[\\\*\\\]'\[^\n\r]*(\n|\r\n|\r)" } */
>> +/* { dg-output

Re: [PATCH v8 4/5] Use the .ACCESS_WITH_SIZE in bound sanitizer.

2024-04-10 Thread Siddhesh Poyarekar 

On 2024-03-29 12:07, Qing Zhao wrote:

gcc/c-family/ChangeLog:

* c-ubsan.cc (get_bound_from_access_with_size): New function.
(ubsan_instrument_bounds): Handle call to .ACCESS_WITH_SIZE.

gcc/testsuite/ChangeLog:

* gcc.dg/ubsan/flex-array-counted-by-bounds-2.c: New test.
* gcc.dg/ubsan/flex-array-counted-by-bounds-3.c: New test.
* gcc.dg/ubsan/flex-array-counted-by-bounds-4.c: New test.
* gcc.dg/ubsan/flex-array-counted-by-bounds.c: New test.
---


This version looks fine to me for stage 1, but I'm not a maintainer so 
you'll need an ack from one to commit.


Thanks,
Sid


  gcc/c-family/c-ubsan.cc   | 42 +
  .../ubsan/flex-array-counted-by-bounds-2.c| 45 ++
  .../ubsan/flex-array-counted-by-bounds-3.c| 34 ++
  .../ubsan/flex-array-counted-by-bounds-4.c| 34 ++
  .../ubsan/flex-array-counted-by-bounds.c  | 46 +++
  5 files changed, 201 insertions(+)
  create mode 100644 gcc/testsuite/gcc.dg/ubsan/flex-array-counted-by-bounds-2.c
  create mode 100644 gcc/testsuite/gcc.dg/ubsan/flex-array-counted-by-bounds-3.c
  create mode 100644 gcc/testsuite/gcc.dg/ubsan/flex-array-counted-by-bounds-4.c
  create mode 100644 gcc/testsuite/gcc.dg/ubsan/flex-array-counted-by-bounds.c

diff --git a/gcc/c-family/c-ubsan.cc b/gcc/c-family/c-ubsan.cc
index 940982819ddf..7cd3c6aa5b88 100644
--- a/gcc/c-family/c-ubsan.cc
+++ b/gcc/c-family/c-ubsan.cc
@@ -376,6 +376,40 @@ ubsan_instrument_return (location_t loc)
return build_call_expr_loc (loc, t, 1, build_fold_addr_expr_loc (loc, 
data));
  }
  
+/* Get the tree that represented the number of counted_by, i.e, the maximum

+   number of the elements of the object that the call to .ACCESS_WITH_SIZE
+   points to, this number will be the bound of the corresponding array.  */
+static tree
+get_bound_from_access_with_size (tree call)
+{
+  if (!is_access_with_size_p (call))
+return NULL_TREE;
+
+  tree ref_to_size = CALL_EXPR_ARG (call, 1);
+  unsigned int class_of_size = TREE_INT_CST_LOW (CALL_EXPR_ARG (call, 2));
+  tree type = TREE_TYPE (CALL_EXPR_ARG (call, 3));
+  tree size = fold_build2 (MEM_REF, type, unshare_expr (ref_to_size),
+  build_int_cst (ptr_type_node, 0));
+  /* If size is negative value, treat it as zero.  */
+  if (!TYPE_UNSIGNED (type))
+  {
+tree cond = fold_build2 (LT_EXPR, boolean_type_node,
+unshare_expr (size), build_zero_cst (type));
+size = fold_build3 (COND_EXPR, type, cond,
+   build_zero_cst (type), size);
+  }
+
+  /* Only when class_of_size is 1, i.e, the number of the elements of
+ the object type, return the size.  */
+  if (class_of_size != 1)
+return NULL_TREE;
+  else
+size = fold_convert (sizetype, size);
+
+  return size;
+}
+
+
  /* Instrument array bounds for ARRAY_REFs.  We create special builtin,
 that gets expanded in the sanopt pass, and make an array dimension
 of it.  ARRAY is the array, *INDEX is an index to the array.
@@ -401,6 +435,14 @@ ubsan_instrument_bounds (location_t loc, tree array, tree 
*index,
  && COMPLETE_TYPE_P (type)
  && integer_zerop (TYPE_SIZE (type)))
bound = build_int_cst (TREE_TYPE (TYPE_MIN_VALUE (domain)), -1);
+  else if (INDIRECT_REF_P (array)
+  && is_access_with_size_p ((TREE_OPERAND (array, 0
+   {
+ bound = get_bound_from_access_with_size ((TREE_OPERAND (array, 0)));
+ bound = fold_build2 (MINUS_EXPR, TREE_TYPE (bound),
+  bound,
+  build_int_cst (TREE_TYPE (bound), 1));
+   }
else
return NULL_TREE;
  }
diff --git a/gcc/testsuite/gcc.dg/ubsan/flex-array-counted-by-bounds-2.c 
b/gcc/testsuite/gcc.dg/ubsan/flex-array-counted-by-bounds-2.c
new file mode 100644
index ..b503320628d2
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/ubsan/flex-array-counted-by-bounds-2.c
@@ -0,0 +1,45 @@
+/* Test the attribute counted_by and its usage in
+   bounds sanitizer combined with VLA.  */
+/* { dg-do run } */
+/* { dg-options "-fsanitize=bounds" } */
+/* { dg-output "index 11 out of bounds for type 'int 
\\\[\\\*\\\]\\\[\\\*\\\]'\[^\n\r]*(\n|\r\n|\r)" } */
+/* { dg-output "\[^\n\r]*index 20 out of bounds for type 'int 
\\\[\\\*\\\]\\\[\\\*\\\]\\\[\\\*\\\]'\[^\n\r]*(\n|\r\n|\r)" } */
+/* { dg-output "\[^\n\r]*index 11 out of bounds for type 'int 
\\\[\\\*\\\]\\\[\\\*\\\]'\[^\n\r]*(\n|\r\n|\r)" } */
+/* { dg-output "\[^\n\r]*index 10 out of bounds for type 'int 
\\\[\\\*\\\]'\[^\n\r]*(\n|\r\n|\r)" } */
+
+
+#include 
+
+void __attribute__((__noinline__)) setup_and_test_vla (int n, int m)
+{
+   struct foo {
+   int n;
+   int p[][n] __attribute__((counted_by(n)));
+   } *f;
+
+   f = (struct foo *) malloc (sizeof(struct foo) + m*sizeof(int[n]));
+   f->n = m;
+   f->p[m][n-1]=1;
+   return;
+}
+
+void

Re: [PATCH v8 4/5] Use the .ACCESS_WITH_SIZE in bound sanitizer.

2024-04-10 Thread Joseph Myers 
The C front-end changes in this patch are OK for GCC 15.

-- 
Joseph S. Myers
josmy...@redhat.com