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Tests to check inconsistent assumptions involving __CPROVER_r_ok #5321
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Original file line number | Diff line number | Diff line change |
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add_test_pl_tests( | ||
"$<TARGET_FILE:cbmc>" | ||
) |
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default: tests.log | ||
|
||
test: | ||
@../test.pl -e -p -c ../../../src/cbmc/cbmc | ||
|
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tests.log: ../test.pl | ||
@../test.pl -e -p -c ../../../src/cbmc/cbmc | ||
|
||
show: | ||
@for dir in *; do \ | ||
if [ -d "$$dir" ]; then \ | ||
vim -o "$$dir/*.c" "$$dir/*.out"; \ | ||
fi; \ | ||
done; | ||
|
||
clean: | ||
find -name '*.out' -execdir $(RM) '{}' \; | ||
$(RM) tests.log |
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@@ -0,0 +1,9 @@ | ||
#include <assert.h> | ||
#include <stdlib.h> | ||
|
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void main() | ||
{ | ||
char *p1; | ||
__CPROVER_assume(__CPROVER_r_ok(p1 - 1, 1)); | ||
*p1; | ||
} |
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Original file line number | Diff line number | Diff line change |
---|---|---|
@@ -0,0 +1,9 @@ | ||
KNOWNBUG | ||
main.c | ||
--pointer-check --no-simplify --no-propagation | ||
^EXIT=0$ | ||
^SIGNAL=0$ | ||
-- | ||
^warning: ignoring | ||
-- | ||
Crashes during the flattening, issue #5328 |
16 changes: 16 additions & 0 deletions
16
regression/cbmc-primitives/r_w_ok_inconsistent_dead/main.c
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@@ -0,0 +1,16 @@ | ||
#include <assert.h> | ||
#include <stdlib.h> | ||
|
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void main() | ||
{ | ||
char *p; | ||
|
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{ | ||
char c; | ||
p = &c; | ||
} | ||
|
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__CPROVER_assume(__CPROVER_r_ok(p, 1)); | ||
assert(0); // fails | ||
*p; // succeeds | ||
} |
13 changes: 13 additions & 0 deletions
13
regression/cbmc-primitives/r_w_ok_inconsistent_dead/test-no-cp.desc
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Original file line number | Diff line number | Diff line change |
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@@ -0,0 +1,13 @@ | ||
FUTURE | ||
main.c | ||
--pointer-check --no-simplify --no-propagation | ||
^EXIT=0$ | ||
^SIGNAL=0$ | ||
^VERIFICATION SUCCESSFUL$ | ||
-- | ||
^warning: ignoring | ||
-- | ||
Tests that an inconsistent assumption involving a pointer to an out of scope | ||
variable and __CPROVER_r_ok() can be detected via assert(0). We use | ||
--no-simplify and --no-propagation to ensure that the case is not solved by the | ||
constant propagation and thus tests the constraint encoding. |
11 changes: 11 additions & 0 deletions
11
regression/cbmc-primitives/r_w_ok_inconsistent_dead/test.desc
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Original file line number | Diff line number | Diff line change |
---|---|---|
@@ -0,0 +1,11 @@ | ||
FUTURE | ||
main.c | ||
--function test_global_pointer --pointer-check | ||
^EXIT=0$ | ||
^SIGNAL=0$ | ||
^VERIFICATION SUCCESSFUL$ | ||
-- | ||
^warning: ignoring | ||
-- | ||
Tests that an inconsistent assumption involving a pointer to an out of scope | ||
variable and __CPROVER_r_ok() can be detected via assert(0). |
12 changes: 12 additions & 0 deletions
12
regression/cbmc-primitives/r_w_ok_inconsistent_deallocated/main.c
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#include <assert.h> | ||
#include <stdlib.h> | ||
|
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void main() | ||
{ | ||
char *p = malloc(1); | ||
free(p); | ||
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__CPROVER_assume(__CPROVER_r_ok(p, 1)); | ||
assert(0); // fails | ||
*p; // succeeds | ||
} |
13 changes: 13 additions & 0 deletions
13
regression/cbmc-primitives/r_w_ok_inconsistent_deallocated/test-no-cp.desc
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Original file line number | Diff line number | Diff line change |
---|---|---|
@@ -0,0 +1,13 @@ | ||
FUTURE | ||
main.c | ||
--pointer-check --no-simplify --no-propagation | ||
^EXIT=0$ | ||
^SIGNAL=0$ | ||
^VERIFICATION SUCCESSFUL$ | ||
-- | ||
^warning: ignoring | ||
-- | ||
Tests that an inconsistent assumption involving a pointer initialized to an | ||
integer address not pointing to memory and __CPROVER_r_ok() can be detected via | ||
assert(0). We use --no-simplify and --no-propagation to ensure that the case is | ||
not solved by the constant propagation and thus tests the constraint encoding. |
12 changes: 12 additions & 0 deletions
12
regression/cbmc-primitives/r_w_ok_inconsistent_deallocated/test.desc
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Original file line number | Diff line number | Diff line change |
---|---|---|
@@ -0,0 +1,12 @@ | ||
FUTURE | ||
main.c | ||
--pointer-check | ||
^EXIT=0$ | ||
^SIGNAL=0$ | ||
^VERIFICATION SUCCESSFUL$ | ||
-- | ||
^warning: ignoring | ||
-- | ||
Tests that an inconsistent assumption involving a pointer initialized to an | ||
integer address not pointing to memory and __CPROVER_r_ok() can be detected via | ||
assert(0). |
14 changes: 14 additions & 0 deletions
14
regression/cbmc-primitives/r_w_ok_inconsistent_integer/main.c
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#include <assert.h> | ||
#include <stdlib.h> | ||
|
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void main() | ||
{ | ||
// pointer with object bits = 123 and offset = 123 | ||
// this is to test with a pointer that does not point to valid memory, but the | ||
// value of which is otherwise not special in any way (like for example a null | ||
// pointer) | ||
char *p = (size_t)123 << (sizeof(char *) * 8 - 8) | 123; | ||
__CPROVER_assume(__CPROVER_r_ok(p, 10)); | ||
assert(0); // fails | ||
*p; // succeeds | ||
} |
13 changes: 13 additions & 0 deletions
13
regression/cbmc-primitives/r_w_ok_inconsistent_integer/test-no-cp.desc
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Original file line number | Diff line number | Diff line change |
---|---|---|
@@ -0,0 +1,13 @@ | ||
FUTURE | ||
main.c | ||
--pointer-check --no-simplify --no-propagation | ||
^EXIT=0$ | ||
^SIGNAL=0$ | ||
^VERIFICATION SUCCESSFUL$ | ||
-- | ||
^warning: ignoring | ||
-- | ||
Tests that an inconsistent assumption involving a pointer initialized to an | ||
integer address not pointing to memory and __CPROVER_r_ok() can be detected via | ||
assert(0). We use --no-simplify and --no-propagation to ensure that the case is | ||
not solved by the constant propagation and thus tests the constraint encoding. |
12 changes: 12 additions & 0 deletions
12
regression/cbmc-primitives/r_w_ok_inconsistent_integer/test.desc
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Original file line number | Diff line number | Diff line change |
---|---|---|
@@ -0,0 +1,12 @@ | ||
FUTURE | ||
main.c | ||
--pointer-check | ||
^EXIT=0$ | ||
^SIGNAL=0$ | ||
^VERIFICATION SUCCESSFUL$ | ||
-- | ||
^warning: ignoring | ||
-- | ||
Tests that an inconsistent assumption involving a pointer initialized to an | ||
integer address not pointing to memory and __CPROVER_r_ok() can be detected via | ||
assert(0). |
12 changes: 12 additions & 0 deletions
12
regression/cbmc-primitives/r_w_ok_inconsistent_invalid/main.c
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@@ -0,0 +1,12 @@ | ||
#include <assert.h> | ||
#include <stdlib.h> | ||
|
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void main() | ||
{ | ||
// special value of the invalid pointer (object bits = 1 and offset = 0), as | ||
// checked for by __CPROVER_is_invalid_pointer() | ||
char *p = (size_t)1 << (sizeof(char *) * 8 - 8); | ||
__CPROVER_assume(__CPROVER_r_ok(p, 10)); | ||
assert(0); // fails | ||
*p; // succeeds | ||
} |
13 changes: 13 additions & 0 deletions
13
regression/cbmc-primitives/r_w_ok_inconsistent_invalid/test-no-cp.desc
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Original file line number | Diff line number | Diff line change |
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@@ -0,0 +1,13 @@ | ||
CORE | ||
main.c | ||
--pointer-check --no-simplify --no-propagation | ||
^EXIT=0$ | ||
^SIGNAL=0$ | ||
^VERIFICATION SUCCESSFUL$ | ||
-- | ||
^warning: ignoring | ||
-- | ||
Tests that an inconsistent assumption involving the special invalid pointer | ||
value and __CPROVER_r_ok() can be detected via assert(0). We use --no-simplify | ||
and --no-propagation to ensure that the case is not solved by the constant | ||
propagation and thus tests the constraint encoding. |
11 changes: 11 additions & 0 deletions
11
regression/cbmc-primitives/r_w_ok_inconsistent_invalid/test.desc
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Original file line number | Diff line number | Diff line change |
---|---|---|
@@ -0,0 +1,11 @@ | ||
CORE | ||
main.c | ||
--pointer-check | ||
^EXIT=0$ | ||
^SIGNAL=0$ | ||
^VERIFICATION SUCCESSFUL$ | ||
-- | ||
^warning: ignoring | ||
-- | ||
Tests that an inconsistent assumption involving the special invalid pointer | ||
value and __CPROVER_r_ok() can be detected via assert(0). |
11 changes: 11 additions & 0 deletions
11
regression/cbmc-primitives/r_w_ok_inconsistent_nondet/main.c
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#include <assert.h> | ||
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char *nondet(); | ||
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void main() | ||
{ | ||
char *p = nondet(); | ||
__CPROVER_assume(__CPROVER_r_ok(p, 10)); | ||
assert(0); // fails | ||
*p; // succeeds | ||
} |
13 changes: 13 additions & 0 deletions
13
regression/cbmc-primitives/r_w_ok_inconsistent_nondet/test-no-cp.desc
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Original file line number | Diff line number | Diff line change |
---|---|---|
@@ -0,0 +1,13 @@ | ||
FUTURE | ||
main.c | ||
--pointer-check --no-simplify --no-propagation | ||
^EXIT=0$ | ||
^SIGNAL=0$ | ||
^VERIFICATION SUCCESSFUL$ | ||
-- | ||
^warning: ignoring | ||
-- | ||
Tests that an inconsistent assumption involving a nondet pointer and | ||
__CPROVER_r_ok() can be detected via assert(0). We use --no-simplify and | ||
--no-propagation to ensure that the case is not solved by the constant | ||
propagation and thus tests the constraint encoding. |
11 changes: 11 additions & 0 deletions
11
regression/cbmc-primitives/r_w_ok_inconsistent_nondet/test.desc
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Original file line number | Diff line number | Diff line change |
---|---|---|
@@ -0,0 +1,11 @@ | ||
FUTURE | ||
main.c | ||
--pointer-check | ||
^EXIT=0$ | ||
^SIGNAL=0$ | ||
^VERIFICATION SUCCESSFUL$ | ||
-- | ||
^warning: ignoring | ||
-- | ||
Tests that an inconsistent assumption involving a nondet pointer and | ||
__CPROVER_r_ok() can be detected via assert(0). |
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@@ -0,0 +1,8 @@ | ||
#include <assert.h> | ||
#include <stdlib.h> | ||
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void main() | ||
{ | ||
char *p = NULL; | ||
assert(!__CPROVER_r_ok(p, 10)); | ||
} |
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Original file line number | Diff line number | Diff line change |
---|---|---|
@@ -0,0 +1,12 @@ | ||
CORE | ||
main.c | ||
--pointer-check --no-simplify --no-propagation | ||
^EXIT=0$ | ||
^SIGNAL=0$ | ||
^VERIFICATION SUCCESSFUL$ | ||
-- | ||
^warning: ignoring | ||
-- | ||
Tests that __CPROVER_r_ok() on a null pointers is false. We use --no-simplify | ||
and --no-propagation to ensure that the case is not solved by the constant | ||
propagation and thus tests the constraint encoding. |
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Original file line number | Diff line number | Diff line change |
---|---|---|
@@ -0,0 +1,10 @@ | ||
CORE | ||
main.c | ||
--pointer-check | ||
^EXIT=0$ | ||
^SIGNAL=0$ | ||
^VERIFICATION SUCCESSFUL$ | ||
-- | ||
^warning: ignoring | ||
-- | ||
Tests that __CPROVER_r_ok() on a null pointers is false |
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Original file line number | Diff line number | Diff line change |
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@@ -0,0 +1,19 @@ | ||
#include <assert.h> | ||
#include <stdlib.h> | ||
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char c1; | ||
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void main() | ||
{ | ||
char c2; | ||
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char *p1 = &c1; | ||
assert(__CPROVER_r_ok(p1, 1)); | ||
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char *p2 = &c2; | ||
assert(__CPROVER_r_ok(p2, 1)); | ||
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char *p3 = malloc(1); | ||
__CPROVER_assume(p1 != NULL); | ||
assert(__CPROVER_r_ok(p3, 1)); | ||
} |
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Original file line number | Diff line number | Diff line change |
---|---|---|
@@ -0,0 +1,13 @@ | ||
CORE | ||
main.c | ||
--pointer-check --no-simplify --no-propagation | ||
^EXIT=0$ | ||
^SIGNAL=0$ | ||
^VERIFICATION SUCCESSFUL$ | ||
-- | ||
^warning: ignoring | ||
-- | ||
Tests that __CPROVER_r_ok() is true for valid pointers to global, local, or | ||
malloced memory. We use --no-simplify and --no-propagation to ensure that the | ||
case is not solved by the constant propagation and thus tests the constraint | ||
encoding. |
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Original file line number | Diff line number | Diff line change |
---|---|---|
@@ -0,0 +1,11 @@ | ||
CORE | ||
main.c | ||
--pointer-check | ||
^EXIT=0$ | ||
^SIGNAL=0$ | ||
^VERIFICATION SUCCESSFUL$ | ||
-- | ||
^warning: ignoring | ||
-- | ||
Tests that __CPROVER_r_ok() is true for valid pointers to global, local, or | ||
malloced memory |
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@@ -0,0 +1,34 @@ | ||
#include <assert.h> | ||
#include <stdlib.h> | ||
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char c1; | ||
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void main() | ||
{ | ||
// We check the conditions for a pointer to global static memory (p1), a | ||
// pointer to local memory (p2), and a pointer to dynamic memory (p3). | ||
// For each pointer, we check: | ||
// (1) whether it is unsafe to access one byte more than was allocated | ||
// (2) whether it is unsafe to access one byte before the allocated memory | ||
// (3) whether it is unsafe to access one byte after the allocated memory | ||
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char c2; | ||
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char *p1 = &c1; | ||
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assert(!__CPROVER_r_ok(p1, 2)); | ||
assert(!__CPROVER_r_ok(p1 - 1, 1)); | ||
assert(!__CPROVER_r_ok(p1 + 1, 1)); | ||
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char *p2 = &c2; | ||
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assert(!__CPROVER_r_ok(p2, 2)); | ||
assert(!__CPROVER_r_ok(p2 - 1, 1)); | ||
assert(!__CPROVER_r_ok(p2 + 1, 1)); | ||
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char *p3 = malloc(1); | ||
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assert(!__CPROVER_r_ok(p3, 2)); | ||
assert(!__CPROVER_r_ok(p3 - 1, 1)); | ||
assert(!__CPROVER_r_ok(p3 + 1, 1)); | ||
Comment on lines
+17
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There was a problem hiding this comment. Choose a reason for hiding this commentThe reason will be displayed to describe this comment to others. Learn more. This is much better imo 💚 |
||
} |
13 changes: 13 additions & 0 deletions
13
regression/cbmc-primitives/r_w_ok_valid_negated/test-no-cp.desc
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Original file line number | Diff line number | Diff line change |
---|---|---|
@@ -0,0 +1,13 @@ | ||
KNOWNBUG | ||
main.c | ||
--pointer-check --no-simplify --no-propagation | ||
^EXIT=0$ | ||
^SIGNAL=0$ | ||
^VERIFICATION SUCCESSFUL$ | ||
-- | ||
^warning: ignoring | ||
-- | ||
Tests that __CPROVER_r_ok() is false for a pointer to a valid memory object, | ||
though potentially with an offset that is out of bounds. We use --no-simplify | ||
and --no-propagation to ensure that the case is not solved by the constant | ||
propagation and thus tests the constraint encoding. |
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Thanks for the improvement - as the reader, I'm still left with the question of why you're constructing such a pointer. I think this would still be improved with a comment as to why this is an interesting pointer. Is it because it tricks cbmc into thinking it is valid?
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Yes, it's a pointer that doesn't point to valid memory but isn't special in any other way. Added a description.