diff options
Diffstat (limited to 'sys-kernel/cairn-sources/files/5.10.7/hardened-patches/0056-slub-Add-support-for-verifying-slab-sanitization.patch')
| -rw-r--r-- | sys-kernel/cairn-sources/files/5.10.7/hardened-patches/0056-slub-Add-support-for-verifying-slab-sanitization.patch | 116 |
1 files changed, 116 insertions, 0 deletions
diff --git a/sys-kernel/cairn-sources/files/5.10.7/hardened-patches/0056-slub-Add-support-for-verifying-slab-sanitization.patch b/sys-kernel/cairn-sources/files/5.10.7/hardened-patches/0056-slub-Add-support-for-verifying-slab-sanitization.patch new file mode 100644 index 000000000000..88a26f6c5358 --- /dev/null +++ b/sys-kernel/cairn-sources/files/5.10.7/hardened-patches/0056-slub-Add-support-for-verifying-slab-sanitization.patch @@ -0,0 +1,116 @@ +From 0df4718423ec96eb9397a9eef554c4cabf2ecc09 Mon Sep 17 00:00:00 2001 +From: Daniel Micay <danielmicay@gmail.com> +Date: Thu, 4 May 2017 15:58:57 -0400 +Subject: [PATCH 056/113] slub: Add support for verifying slab sanitization + +This is an extension to the sanitization feature in PaX for when +sacricifing more performance for security is acceptable. + +The initial version from Daniel Micay was relying on PAGE_SANITIZE. It +now relies on upstream's init_on_free. + +Signed-off-by: Daniel Micay <danielmicay@gmail.com> +Signed-off-by: Thibaut Sautereau <thibaut.sautereau@ssi.gouv.fr> +Signed-off-by: Levente Polyak <levente@leventepolyak.net> +--- + mm/slub.c | 36 ++++++++++++++++++++++++++++++++---- + security/Kconfig.hardening | 8 ++++++++ + 2 files changed, 40 insertions(+), 4 deletions(-) + +diff --git a/mm/slub.c b/mm/slub.c +index cf24f74e01de..d42d2709526a 100644 +--- a/mm/slub.c ++++ b/mm/slub.c +@@ -127,6 +127,12 @@ static inline bool kmem_cache_debug(struct kmem_cache *s) + return kmem_cache_debug_flags(s, SLAB_DEBUG_FLAGS); + } + ++static inline bool has_sanitize_verify(struct kmem_cache *s) ++{ ++ return IS_ENABLED(CONFIG_SLAB_SANITIZE_VERIFY) && ++ slab_want_init_on_free(s); ++} ++ + void *fixup_red_left(struct kmem_cache *s, void *p) + { + if (kmem_cache_debug_flags(s, SLAB_RED_ZONE)) +@@ -1571,7 +1577,7 @@ static inline bool slab_free_freelist_hook(struct kmem_cache *s, + : 0; + memset((char *)object + s->inuse, 0, + s->size - s->inuse - rsize); +- if (s->ctor) ++ if (!IS_ENABLED(CONFIG_SLAB_SANITIZE_VERIFY) && s->ctor) + s->ctor(object); + } + /* If object's reuse doesn't have to be delayed */ +@@ -1606,7 +1612,7 @@ static void *setup_object(struct kmem_cache *s, struct page *page, + { + setup_object_debug(s, page, object); + object = kasan_init_slab_obj(s, object); +- if (unlikely(s->ctor)) { ++ if (unlikely(s->ctor) && !has_sanitize_verify(s)) { + kasan_unpoison_object_data(s, object); + s->ctor(object); + kasan_poison_object_data(s, object); +@@ -2897,7 +2903,16 @@ static __always_inline void *slab_alloc_node(struct kmem_cache *s, + + maybe_wipe_obj_freeptr(s, object); + +- if (unlikely(slab_want_init_on_alloc(gfpflags, s)) && object) ++ if (has_sanitize_verify(s) && object) { ++ /* KASAN hasn't unpoisoned the object yet (this is done in the ++ * post-alloc hook), so let's do it temporarily. ++ */ ++ kasan_unpoison_object_data(s, object); ++ BUG_ON(memchr_inv(object, 0, s->object_size)); ++ if (s->ctor) ++ s->ctor(object); ++ kasan_poison_object_data(s, object); ++ } else if (unlikely(slab_want_init_on_alloc(gfpflags, s)) && object) + memset(object, 0, s->object_size); + + slab_post_alloc_hook(s, objcg, gfpflags, 1, &object); +@@ -3337,7 +3352,20 @@ int kmem_cache_alloc_bulk(struct kmem_cache *s, gfp_t flags, size_t size, + local_irq_enable(); + + /* Clear memory outside IRQ disabled fastpath loop */ +- if (unlikely(slab_want_init_on_alloc(flags, s))) { ++ if (has_sanitize_verify(s)) { ++ int j; ++ ++ for (j = 0; j < i; j++) { ++ /* KASAN hasn't unpoisoned the object yet (this is done ++ * in the post-alloc hook), so let's do it temporarily. ++ */ ++ kasan_unpoison_object_data(s, p[j]); ++ BUG_ON(memchr_inv(p[j], 0, s->object_size)); ++ if (s->ctor) ++ s->ctor(p[j]); ++ kasan_poison_object_data(s, p[j]); ++ } ++ } else if (unlikely(slab_want_init_on_alloc(flags, s))) { + int j; + + for (j = 0; j < i; j++) +diff --git a/security/Kconfig.hardening b/security/Kconfig.hardening +index 3d2f1d2c3d80..a718487ad717 100644 +--- a/security/Kconfig.hardening ++++ b/security/Kconfig.hardening +@@ -224,6 +224,14 @@ config PAGE_SANITIZE_VERIFY + When init_on_free is enabled, verify that newly allocated pages + are zeroed to detect write-after-free bugs. + ++config SLAB_SANITIZE_VERIFY ++ bool "Verify sanitized SLAB allocations" ++ default y ++ depends on !KASAN ++ help ++ When init_on_free is enabled, verify that newly allocated slab ++ objects are zeroed to detect write-after-free bugs. ++ + endmenu + + endmenu +-- +2.30.0 + |