Merge tag 'bpf-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf

Pull bpf fixes from Alexei Starovoitov:

 - Fix kCFI failures in JITed BPF code on arm64 (Sami Tolvanen, Puranjay
   Mohan, Mark Rutland, Maxwell Bland)

 - Disallow tail calls between BPF programs that use different cgroup
   local storage maps to prevent out-of-bounds access (Daniel Borkmann)

 - Fix unaligned access in flow_dissector and netfilter BPF programs
   (Paul Chaignon)

 - Avoid possible use of uninitialized mod_len in libbpf (Achill
   Gilgenast)

* tag 'bpf-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf:
  selftests/bpf: Test for unaligned flow_dissector ctx access
  bpf: Improve ctx access verifier error message
  bpf: Check netfilter ctx accesses are aligned
  bpf: Check flow_dissector ctx accesses are aligned
  arm64/cfi,bpf: Support kCFI + BPF on arm64
  cfi: Move BPF CFI types and helpers to generic code
  cfi: add C CFI type macro
  libbpf: Avoid possible use of uninitialized mod_len
  bpf: Fix oob access in cgroup local storage
  bpf: Move cgroup iterator helpers to bpf.h
  bpf: Move bpf map owner out of common struct
  bpf: Add cookie object to bpf maps

4 files changed, 102 insertions, 33 deletions

diff --git a/include/linux/bpf-cgroup.h b/include/linux/bpf-cgroup.h
index 082ccd8ad96b..aedf573bdb42 100644
--- a/include/linux/bpf-cgroup.h
+++ b/include/linux/bpf-cgroup.h
@@ -77,9 +77,6 @@ to_cgroup_bpf_attach_type(enum bpf_attach_type attach_type)
 extern struct static_key_false cgroup_bpf_enabled_key[MAX_CGROUP_BPF_ATTACH_TYPE];
 #define cgroup_bpf_enabled(atype) static_branch_unlikely(&cgroup_bpf_enabled_key[atype])
 
-#define for_each_cgroup_storage_type(stype) \
-	for (stype = 0; stype < MAX_BPF_CGROUP_STORAGE_TYPE; stype++)
-
 struct bpf_cgroup_storage_map;
 
 struct bpf_storage_buffer {
@@ -510,8 +507,6 @@ static inline int bpf_percpu_cgroup_storage_update(struct bpf_map *map,
 #define BPF_CGROUP_RUN_PROG_SETSOCKOPT(sock, level, optname, optval, optlen, \
 				       kernel_optval) ({ 0; })
 
-#define for_each_cgroup_storage_type(stype) for (; false; )
-
 #endif /* CONFIG_CGROUP_BPF */
 
 #endif /* _BPF_CGROUP_H */
diff --git a/include/linux/bpf.h b/include/linux/bpf.h
index f9cd2164ed23..cc700925b802 100644
--- a/include/linux/bpf.h
+++ b/include/linux/bpf.h
@@ -208,6 +208,20 @@ enum btf_field_type {
 	BPF_RES_SPIN_LOCK = (1 << 12),
 };
 
+enum bpf_cgroup_storage_type {
+	BPF_CGROUP_STORAGE_SHARED,
+	BPF_CGROUP_STORAGE_PERCPU,
+	__BPF_CGROUP_STORAGE_MAX
+#define MAX_BPF_CGROUP_STORAGE_TYPE __BPF_CGROUP_STORAGE_MAX
+};
+
+#ifdef CONFIG_CGROUP_BPF
+# define for_each_cgroup_storage_type(stype) \
+	for (stype = 0; stype < MAX_BPF_CGROUP_STORAGE_TYPE; stype++)
+#else
+# define for_each_cgroup_storage_type(stype) for (; false; )
+#endif /* CONFIG_CGROUP_BPF */
+
 typedef void (*btf_dtor_kfunc_t)(void *);
 
 struct btf_field_kptr {
@@ -260,6 +274,19 @@ struct bpf_list_node_kern {
 	void *owner;
 } __attribute__((aligned(8)));
 
+/* 'Ownership' of program-containing map is claimed by the first program
+ * that is going to use this map or by the first program which FD is
+ * stored in the map to make sure that all callers and callees have the
+ * same prog type, JITed flag and xdp_has_frags flag.
+ */
+struct bpf_map_owner {
+	enum bpf_prog_type type;
+	bool jited;
+	bool xdp_has_frags;
+	u64 storage_cookie[MAX_BPF_CGROUP_STORAGE_TYPE];
+	const struct btf_type *attach_func_proto;
+};
+
 struct bpf_map {
 	const struct bpf_map_ops *ops;
 	struct bpf_map *inner_map_meta;
@@ -292,24 +319,15 @@ struct bpf_map {
 		struct rcu_head rcu;
 	};
 	atomic64_t writecnt;
-	/* 'Ownership' of program-containing map is claimed by the first program
-	 * that is going to use this map or by the first program which FD is
-	 * stored in the map to make sure that all callers and callees have the
-	 * same prog type, JITed flag and xdp_has_frags flag.
-	 */
-	struct {
-		const struct btf_type *attach_func_proto;
-		spinlock_t lock;
-		enum bpf_prog_type type;
-		bool jited;
-		bool xdp_has_frags;
-	} owner;
+	spinlock_t owner_lock;
+	struct bpf_map_owner *owner;
 	bool bypass_spec_v1;
 	bool frozen; /* write-once; write-protected by freeze_mutex */
 	bool free_after_mult_rcu_gp;
 	bool free_after_rcu_gp;
 	atomic64_t sleepable_refcnt;
 	s64 __percpu *elem_count;
+	u64 cookie; /* write-once */
 };
 
 static inline const char *btf_field_type_name(enum btf_field_type type)
@@ -1082,14 +1100,6 @@ struct bpf_prog_offload {
 	u32			jited_len;
 };
 
-enum bpf_cgroup_storage_type {
-	BPF_CGROUP_STORAGE_SHARED,
-	BPF_CGROUP_STORAGE_PERCPU,
-	__BPF_CGROUP_STORAGE_MAX
-};
-
-#define MAX_BPF_CGROUP_STORAGE_TYPE __BPF_CGROUP_STORAGE_MAX
-
 /* The longest tracepoint has 12 args.
  * See include/trace/bpf_probe.h
  */
@@ -2108,6 +2118,16 @@ static inline bool bpf_map_flags_access_ok(u32 access_flags)
 	       (BPF_F_RDONLY_PROG | BPF_F_WRONLY_PROG);
 }
 
+static inline struct bpf_map_owner *bpf_map_owner_alloc(struct bpf_map *map)
+{
+	return kzalloc(sizeof(*map->owner), GFP_ATOMIC);
+}
+
+static inline void bpf_map_owner_free(struct bpf_map *map)
+{
+	kfree(map->owner);
+}
+
 struct bpf_event_entry {
 	struct perf_event *event;
 	struct file *perf_file;
diff --git a/include/linux/cfi.h b/include/linux/cfi.h
index 1db17ecbb86c..52a98886a455 100644
--- a/include/linux/cfi.h
+++ b/include/linux/cfi.h
@@ -11,16 +11,9 @@
 #include <linux/module.h>
 #include <asm/cfi.h>
 
+#ifdef CONFIG_CFI_CLANG
 extern bool cfi_warn;
 
-#ifndef cfi_get_offset
-static inline int cfi_get_offset(void)
-{
-	return 0;
-}
-#endif
-
-#ifdef CONFIG_CFI_CLANG
 enum bug_trap_type report_cfi_failure(struct pt_regs *regs, unsigned long addr,
 				      unsigned long *target, u32 type);
 
@@ -29,6 +22,44 @@ static inline enum bug_trap_type report_cfi_failure_noaddr(struct pt_regs *regs,
 {
 	return report_cfi_failure(regs, addr, NULL, 0);
 }
+
+#ifndef cfi_get_offset
+/*
+ * Returns the CFI prefix offset. By default, the compiler emits only
+ * a 4-byte CFI type hash before the function. If an architecture
+ * uses -fpatchable-function-entry=N,M where M>0 to change the prefix
+ * offset, they must override this function.
+ */
+static inline int cfi_get_offset(void)
+{
+	return 4;
+}
+#endif
+
+#ifndef cfi_get_func_hash
+static inline u32 cfi_get_func_hash(void *func)
+{
+	u32 hash;
+
+	if (get_kernel_nofault(hash, func - cfi_get_offset()))
+		return 0;
+
+	return hash;
+}
+#endif
+
+/* CFI type hashes for BPF function types */
+extern u32 cfi_bpf_hash;
+extern u32 cfi_bpf_subprog_hash;
+
+#else /* CONFIG_CFI_CLANG */
+
+static inline int cfi_get_offset(void) { return 0; }
+static inline u32 cfi_get_func_hash(void *func) { return 0; }
+
+#define cfi_bpf_hash 0U
+#define cfi_bpf_subprog_hash 0U
+
 #endif /* CONFIG_CFI_CLANG */
 
 #ifdef CONFIG_ARCH_USES_CFI_TRAPS
diff --git a/include/linux/cfi_types.h b/include/linux/cfi_types.h
index 6b8713675765..685f7181780f 100644
--- a/include/linux/cfi_types.h
+++ b/include/linux/cfi_types.h
@@ -41,5 +41,28 @@
 	SYM_TYPED_START(name, SYM_L_GLOBAL, SYM_A_ALIGN)
 #endif
 
+#else /* __ASSEMBLY__ */
+
+#ifdef CONFIG_CFI_CLANG
+#define DEFINE_CFI_TYPE(name, func)						\
+	/*									\
+	 * Force a reference to the function so the compiler generates		\
+	 * __kcfi_typeid_<func>.						\
+	 */									\
+	__ADDRESSABLE(func);							\
+	/* u32 name __ro_after_init = __kcfi_typeid_<func> */			\
+	extern u32 name;							\
+	asm (									\
+	"	.pushsection	.data..ro_after_init,\"aw\",\%progbits	\n"	\
+	"	.type	" #name ",\%object				\n"	\
+	"	.globl	" #name "					\n"	\
+	"	.p2align	2, 0x0					\n"	\
+	#name ":							\n"	\
+	"	.4byte	__kcfi_typeid_" #func "				\n"	\
+	"	.size	" #name ", 4					\n"	\
+	"	.popsection						\n"	\
+	);
+#endif
+
 #endif /* __ASSEMBLY__ */
 #endif /* _LINUX_CFI_TYPES_H */