diff options
| -rw-r--r-- | lib/livepatch/test_klp_shadow_vars.c | 119 | ||||
| -rw-r--r-- | samples/livepatch/livepatch-shadow-fix1.c | 39 | ||||
| -rw-r--r-- | samples/livepatch/livepatch-shadow-fix2.c | 4 | ||||
| -rw-r--r-- | samples/livepatch/livepatch-shadow-mod.c | 4 |
4 files changed, 99 insertions, 67 deletions
diff --git a/lib/livepatch/test_klp_shadow_vars.c b/lib/livepatch/test_klp_shadow_vars.c index fe5c413efe96..f0b5a1d24e55 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 e89ca4546114..918ce17b43fd 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 50d223b82e8b..29fe5cd42047 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 ecfe83a943a7..7e753b0d2fa6 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; |