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

1 files changed, 15 insertions, 0 deletions

diff --git a/kernel/cfi.c b/kernel/cfi.c
index 422fa4f958ae..4dad04ead06c 100644
--- a/kernel/cfi.c
+++ b/kernel/cfi.c
@@ -5,6 +5,8 @@
  * Copyright (C) 2022 Google LLC
  */
 
+#include <linux/bpf.h>
+#include <linux/cfi_types.h>
 #include <linux/cfi.h>
 
 bool cfi_warn __ro_after_init = IS_ENABLED(CONFIG_CFI_PERMISSIVE);
@@ -27,6 +29,19 @@ enum bug_trap_type report_cfi_failure(struct pt_regs *regs, unsigned long addr,
 	return BUG_TRAP_TYPE_BUG;
 }
 
+/*
+ * Declare two non-existent functions with types that match bpf_func_t and
+ * bpf_callback_t pointers, and use DEFINE_CFI_TYPE to define type hash
+ * variables for each function type. The cfi_bpf_* variables are used by
+ * arch-specific BPF JIT implementations to ensure indirectly callable JIT
+ * code has matching CFI type hashes.
+ */
+extern typeof(*(bpf_func_t)0) __bpf_prog_runX;
+DEFINE_CFI_TYPE(cfi_bpf_hash, __bpf_prog_runX);
+
+extern typeof(*(bpf_callback_t)0) __bpf_callback_fn;
+DEFINE_CFI_TYPE(cfi_bpf_subprog_hash, __bpf_callback_fn);
+
 #ifdef CONFIG_ARCH_USES_CFI_TRAPS
 static inline unsigned long trap_address(s32 *p)
 {