diff --git a/lib/livepatch/test_klp_shadow_vars.c b/lib/livepatch/test_klp_shadow_vars.c
index fe5c413efe96586a7f21e01a1376743781f55ae5..f0b5a1d24e558109d913dba7f9b6b44372f43df1 100644
--- a/lib/livepatch/test_klp_shadow_vars.c
+++ b/lib/livepatch/test_klp_shadow_vars.c
@@ -60,36 +60,43 @@ static int ptr_id(void *ptr)
*/
static void *shadow_get(void *obj, unsigned long id)
{
- void *ret = klp_shadow_get(obj, id);
+ int **sv;
+ sv = klp_shadow_get(obj, id);
pr_info("klp_%s(obj=PTR%d, id=0x%lx) = PTR%d\n",
- __func__, ptr_id(obj), id, ptr_id(ret));
+ __func__, ptr_id(obj), id, ptr_id(sv));
- return ret;
+ return sv;
}
static void *shadow_alloc(void *obj, unsigned long id, size_t size,
gfp_t gfp_flags, klp_shadow_ctor_t ctor,
void *ctor_data)
{
- void *ret = klp_shadow_alloc(obj, id, size, gfp_flags, ctor,
- ctor_data);
+ int **var = ctor_data;
+ int **sv;
+
+ sv = klp_shadow_alloc(obj, id, size, gfp_flags, ctor, var);
pr_info("klp_%s(obj=PTR%d, id=0x%lx, size=%zx, gfp_flags=%pGg), ctor=PTR%d, ctor_data=PTR%d = PTR%d\n",
__func__, ptr_id(obj), id, size, &gfp_flags, ptr_id(ctor),
- ptr_id(ctor_data), ptr_id(ret));
- return ret;
+ ptr_id(*var), ptr_id(sv));
+
+ return sv;
}
static void *shadow_get_or_alloc(void *obj, unsigned long id, size_t size,
gfp_t gfp_flags, klp_shadow_ctor_t ctor,
void *ctor_data)
{
- void *ret = klp_shadow_get_or_alloc(obj, id, size, gfp_flags, ctor,
- ctor_data);
+ int **var = ctor_data;
+ int **sv;
+
+ sv = klp_shadow_get_or_alloc(obj, id, size, gfp_flags, ctor, var);
pr_info("klp_%s(obj=PTR%d, id=0x%lx, size=%zx, gfp_flags=%pGg), ctor=PTR%d, ctor_data=PTR%d = PTR%d\n",
__func__, ptr_id(obj), id, size, &gfp_flags, ptr_id(ctor),
- ptr_id(ctor_data), ptr_id(ret));
- return ret;
+ ptr_id(*var), ptr_id(sv));
+
+ return sv;
}
static void shadow_free(void *obj, unsigned long id, klp_shadow_dtor_t dtor)
@@ -110,58 +117,70 @@ static void shadow_free_all(unsigned long id, klp_shadow_dtor_t dtor)
/* Shadow variable constructor - remember simple pointer data */
static int shadow_ctor(void *obj, void *shadow_data, void *ctor_data)
{
- int **shadow_int = shadow_data;
- *shadow_int = ctor_data;
+ int **sv = shadow_data;
+ int **var = ctor_data;
+
+ if (!var)
+ return -EINVAL;
+
+ *sv = *var;
pr_info("%s: PTR%d -> PTR%d\n",
- __func__, ptr_id(shadow_int), ptr_id(ctor_data));
+ __func__, ptr_id(sv), ptr_id(*var));
return 0;
}
static void shadow_dtor(void *obj, void *shadow_data)
{
+ int **sv = shadow_data;
+
pr_info("%s(obj=PTR%d, shadow_data=PTR%d)\n",
- __func__, ptr_id(obj), ptr_id(shadow_data));
+ __func__, ptr_id(obj), ptr_id(sv));
}
static int test_klp_shadow_vars_init(void)
{
void *obj = THIS_MODULE;
int id = 0x1234;
- size_t size = sizeof(int *);
gfp_t gfp_flags = GFP_KERNEL;
int var1, var2, var3, var4;
+ int *pv1, *pv2, *pv3, *pv4;
int **sv1, **sv2, **sv3, **sv4;
- void *ret;
+ int **sv;
+
+ pv1 = &var1;
+ pv2 = &var2;
+ pv3 = &var3;
+ pv4 = &var4;
ptr_id(NULL);
- ptr_id(&var1);
- ptr_id(&var2);
- ptr_id(&var3);
- ptr_id(&var4);
+ ptr_id(pv1);
+ ptr_id(pv2);
+ ptr_id(pv3);
+ ptr_id(pv4);
/*
* With an empty shadow variable hash table, expect not to find
* any matches.
*/
- ret = shadow_get(obj, id);
- if (!ret)
+ sv = shadow_get(obj, id);
+ if (!sv)
pr_info(" got expected NULL result\n");
/*
* Allocate a few shadow variables with different <obj> and <id>.
*/
- sv1 = shadow_alloc(obj, id, size, gfp_flags, shadow_ctor, &var1);
+ sv1 = shadow_alloc(obj, id, sizeof(pv1), gfp_flags, shadow_ctor, &pv1);
if (!sv1)
return -ENOMEM;
- sv2 = shadow_alloc(obj + 1, id, size, gfp_flags, shadow_ctor, &var2);
+ sv2 = shadow_alloc(obj + 1, id, sizeof(pv2), gfp_flags, shadow_ctor, &pv2);
if (!sv2)
return -ENOMEM;
- sv3 = shadow_alloc(obj, id + 1, size, gfp_flags, shadow_ctor, &var3);
+ sv3 = shadow_alloc(obj, id + 1, sizeof(pv3), gfp_flags, shadow_ctor, &pv3);
if (!sv3)
return -ENOMEM;
@@ -169,23 +188,23 @@ static int test_klp_shadow_vars_init(void)
* Verify we can find our new shadow variables and that they point
* to expected data.
*/
- ret = shadow_get(obj, id);
- if (!ret)
+ sv = shadow_get(obj, id);
+ if (!sv)
return -EINVAL;
- if (ret == sv1 && *sv1 == &var1)
+ if (sv == sv1 && *sv1 == pv1)
pr_info(" got expected PTR%d -> PTR%d result\n",
ptr_id(sv1), ptr_id(*sv1));
- ret = shadow_get(obj + 1, id);
- if (!ret)
+ sv = shadow_get(obj + 1, id);
+ if (!sv)
return -EINVAL;
- if (ret == sv2 && *sv2 == &var2)
+ if (sv == sv2 && *sv2 == pv2)
pr_info(" got expected PTR%d -> PTR%d result\n",
ptr_id(sv2), ptr_id(*sv2));
- ret = shadow_get(obj, id + 1);
- if (!ret)
+ sv = shadow_get(obj, id + 1);
+ if (!sv)
return -EINVAL;
- if (ret == sv3 && *sv3 == &var3)
+ if (sv == sv3 && *sv3 == pv3)
pr_info(" got expected PTR%d -> PTR%d result\n",
ptr_id(sv3), ptr_id(*sv3));
@@ -193,14 +212,14 @@ static int test_klp_shadow_vars_init(void)
* Allocate or get a few more, this time with the same <obj>, <id>.
* The second invocation should return the same shadow var.
*/
- sv4 = shadow_get_or_alloc(obj + 2, id, size, gfp_flags, shadow_ctor, &var4);
+ sv4 = shadow_get_or_alloc(obj + 2, id, sizeof(pv4), gfp_flags, shadow_ctor, &pv4);
if (!sv4)
return -ENOMEM;
- ret = shadow_get_or_alloc(obj + 2, id, size, gfp_flags, shadow_ctor, &var4);
- if (!ret)
+ sv = shadow_get_or_alloc(obj + 2, id, sizeof(pv4), gfp_flags, shadow_ctor, &pv4);
+ if (!sv)
return -EINVAL;
- if (ret == sv4 && *sv4 == &var4)
+ if (sv == sv4 && *sv4 == pv4)
pr_info(" got expected PTR%d -> PTR%d result\n",
ptr_id(sv4), ptr_id(*sv4));
@@ -209,27 +228,27 @@ static int test_klp_shadow_vars_init(void)
* longer find them.
*/
shadow_free(obj, id, shadow_dtor); /* sv1 */
- ret = shadow_get(obj, id);
- if (!ret)
+ sv = shadow_get(obj, id);
+ if (!sv)
pr_info(" got expected NULL result\n");
shadow_free(obj + 1, id, shadow_dtor); /* sv2 */
- ret = shadow_get(obj + 1, id);
- if (!ret)
+ sv = shadow_get(obj + 1, id);
+ if (!sv)
pr_info(" got expected NULL result\n");
shadow_free(obj + 2, id, shadow_dtor); /* sv4 */
- ret = shadow_get(obj + 2, id);
- if (!ret)
+ sv = shadow_get(obj + 2, id);
+ if (!sv)
pr_info(" got expected NULL result\n");
/*
* We should still find an <id+1> variable.
*/
- ret = shadow_get(obj, id + 1);
- if (!ret)
+ sv = shadow_get(obj, id + 1);
+ if (!sv)
return -EINVAL;
- if (ret == sv3 && *sv3 == &var3)
+ if (sv == sv3 && *sv3 == pv3)
pr_info(" got expected PTR%d -> PTR%d result\n",
ptr_id(sv3), ptr_id(*sv3));
@@ -237,8 +256,8 @@ static int test_klp_shadow_vars_init(void)
* Free all the <id+1> variables, too.
*/
shadow_free_all(id + 1, shadow_dtor); /* sv3 */
- ret = shadow_get(obj, id);
- if (!ret)
+ sv = shadow_get(obj, id);
+ if (!sv)
pr_info(" shadow_get() got expected NULL result\n");
diff --git a/samples/livepatch/livepatch-shadow-fix1.c b/samples/livepatch/livepatch-shadow-fix1.c
index e89ca4546114e9bee9105a91f1aa9ee554dd1427..918ce17b43fda2d732075a6720f1655fbd22f577 100644
--- a/samples/livepatch/livepatch-shadow-fix1.c
+++ b/samples/livepatch/livepatch-shadow-fix1.c
@@ -52,17 +52,21 @@ struct dummy {
*/
static int shadow_leak_ctor(void *obj, void *shadow_data, void *ctor_data)
{
- void **shadow_leak = shadow_data;
- void *leak = ctor_data;
+ int **shadow_leak = shadow_data;
+ int **leak = ctor_data;
- *shadow_leak = leak;
+ if (!ctor_data)
+ return -EINVAL;
+
+ *shadow_leak = *leak;
return 0;
}
static struct dummy *livepatch_fix1_dummy_alloc(void)
{
struct dummy *d;
- void *leak;
+ int *leak;
+ int **shadow_leak;
d = kzalloc(sizeof(*d), GFP_KERNEL);
if (!d)
@@ -76,25 +80,34 @@ static struct dummy *livepatch_fix1_dummy_alloc(void)
* variable. A patched dummy_free routine can later fetch this
* pointer to handle resource release.
*/
- leak = kzalloc(sizeof(int), GFP_KERNEL);
- if (!leak) {
- kfree(d);
- return NULL;
+ leak = kzalloc(sizeof(*leak), GFP_KERNEL);
+ if (!leak)
+ goto err_leak;
+
+ shadow_leak = klp_shadow_alloc(d, SV_LEAK, sizeof(leak), GFP_KERNEL,
+ shadow_leak_ctor, &leak);
+ if (!shadow_leak) {
+ pr_err("%s: failed to allocate shadow variable for the leaking pointer: dummy @ %p, leak @ %p\n",
+ __func__, d, leak);
+ goto err_shadow;
}
- klp_shadow_alloc(d, SV_LEAK, sizeof(leak), GFP_KERNEL,
- shadow_leak_ctor, leak);
-
pr_info("%s: dummy @ %p, expires @ %lx\n",
__func__, d, d->jiffies_expire);
return d;
+
+err_shadow:
+ kfree(leak);
+err_leak:
+ kfree(d);
+ return NULL;
}
static void livepatch_fix1_dummy_leak_dtor(void *obj, void *shadow_data)
{
void *d = obj;
- void **shadow_leak = shadow_data;
+ int **shadow_leak = shadow_data;
kfree(*shadow_leak);
pr_info("%s: dummy @ %p, prevented leak @ %p\n",
@@ -103,7 +116,7 @@ static void livepatch_fix1_dummy_leak_dtor(void *obj, void *shadow_data)
static void livepatch_fix1_dummy_free(struct dummy *d)
{
- void **shadow_leak;
+ int **shadow_leak;
/*
* Patch: fetch the saved SV_LEAK shadow variable, detach and
diff --git a/samples/livepatch/livepatch-shadow-fix2.c b/samples/livepatch/livepatch-shadow-fix2.c
index 50d223b82e8b5643cb8ced9b04c6baa8df7d511b..29fe5cd420472ad2e9e81188132d0ce47b6a55b8 100644
--- a/samples/livepatch/livepatch-shadow-fix2.c
+++ b/samples/livepatch/livepatch-shadow-fix2.c
@@ -59,7 +59,7 @@ static bool livepatch_fix2_dummy_check(struct dummy *d, unsigned long jiffies)
static void livepatch_fix2_dummy_leak_dtor(void *obj, void *shadow_data)
{
void *d = obj;
- void **shadow_leak = shadow_data;
+ int **shadow_leak = shadow_data;
kfree(*shadow_leak);
pr_info("%s: dummy @ %p, prevented leak @ %p\n",
@@ -68,7 +68,7 @@ static void livepatch_fix2_dummy_leak_dtor(void *obj, void *shadow_data)
static void livepatch_fix2_dummy_free(struct dummy *d)
{
- void **shadow_leak;
+ int **shadow_leak;
int *shadow_count;
/* Patch: copy the memory leak patch from the fix1 module. */
diff --git a/samples/livepatch/livepatch-shadow-mod.c b/samples/livepatch/livepatch-shadow-mod.c
index ecfe83a943a79d4178de48121bf5467a2561d43e..7e753b0d2fa611524c9e2adbe02c8fa3e9b6015e 100644
--- a/samples/livepatch/livepatch-shadow-mod.c
+++ b/samples/livepatch/livepatch-shadow-mod.c
@@ -95,7 +95,7 @@ struct dummy {
static __used noinline struct dummy *dummy_alloc(void)
{
struct dummy *d;
- void *leak;
+ int *leak;
d = kzalloc(sizeof(*d), GFP_KERNEL);
if (!d)
@@ -105,7 +105,7 @@ static __used noinline struct dummy *dummy_alloc(void)
msecs_to_jiffies(1000 * EXPIRE_PERIOD);
/* Oops, forgot to save leak! */
- leak = kzalloc(sizeof(int), GFP_KERNEL);
+ leak = kzalloc(sizeof(*leak), GFP_KERNEL);
if (!leak) {
kfree(d);
return NULL;