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

Pull bpf fixes from Alexei Starovoitov:
 "This mainly contains verifier fixes that address bugs reported by
  Nicholas Carlini.

   - Fix incorrect non-NULL inference in pointer comparisons: pointer
     types that may be NULL at runtime, pointers with unbounded offsets,
     JMP32 comparisons with zero, and imprecise zero registers (Eduard
     Zingerman)

   - Fix precision tracking for half-dead zero spills, ld_abs/ld_ind
     implicit subprog exit, bpf_loop() callbacks, linked scalar ids and
     NULL call arguments (Eduard Zingerman)

   - Reject BPF_PSEUDO_FUNC reference to the main program, fix zero
     extension of arena 32-bit cmpxchg, don't rewrite bpf_fastcall
     patterns entered by a jump (Eduard Zingerman)

   - Fix percpu map update and BPF_F_CPU validation with sparse CPU IDs
     (Hui Su)

   - Fix NULL-ptr-derefs in bpf_snprintf_btf() for void and VAR types,
     and reject key-less BTF for hash maps (Jiayuan Chen)

   - Various fixes (Kumar Kartikeya Dwivedi):
       - Fix out-of-bounds access in disassembler on invalid LDSX
         instruction
       - mark siginfo of signal tracepoints as scalar and
         sched_process_wait argument as nullable
       - mark faultable stack helpers as sleepable
       - reject tail calls and legacy packet loads from callbacks
       - enforce rbtree callback lock restrictions for resilient locks
       - require MEM_PERCPU for percpu kptr stores
       - clear NON_OWN_REF after RCU protection ends
       - mark NULL kptr stores precise
       - preserve inner map identity in callback frames
       - reject non-scalar bpf_loop() iteration counts

   - Fix trampoline allocation slowdown on x86 by using
     EXECMEM_MODULE_DATA (Mike Rapoport)

   - Keep bpf_refcount_acquire() nullable for borrowed RCU kptrs and
     reject untrusted allocated-object pointers (Ning Ding)

   - Fix special fields handling in recycled rhtab elements (Nuoqi Gui,
     Yuan Chen)"

* tag 'bpf-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf: (86 commits)
  bpf, riscv: Make arena support depend on ZACAS
  selftests/bpf: Test pointer bpf_loop iteration count rejection
  bpf: Reject non-scalar bpf_loop iteration counts
  bpf: use mark_arg_precision() in check_mem_size_reg()
  bpf: propagate mark_chain_precision() errors out of loop_flag_is_zero()
  selftests/bpf: precision of a NULL global subprogram BTF_ID argument
  bpf: mark a NULL BTF_ID argument of a global subprogram precise
  selftests/bpf: precision of a NULL kfunc argument
  bpf: mark a NULL kfunc argument precise
  selftests/bpf: precision of a NULL global subprogram memory argument
  bpf: mark a NULL memory argument of a call precise
  selftests/bpf: precision of a NULL helper argument
  bpf: mark a NULL call argument precise
  selftests/bpf: Test inner map identities in callbacks
  bpf: Preserve inner map identity in callback frames
  selftests/bpf: Test imprecise scalar kptr stores
  bpf: Mark NULL kptr stores precise
  selftests/bpf: Test rhtab kptr cancellation semantics
  bpf: Cancel special fields when recycling rhtab elements
  selftests/bpf: Test timer field on recycled rhtab element
  ...

2 files changed, 14 insertions, 4 deletions

diff --git a/arch/riscv/net/bpf_jit_comp64.c b/arch/riscv/net/bpf_jit_comp64.c
index 74efe4b138d2..151031e97a24 100644
--- a/arch/riscv/net/bpf_jit_comp64.c
+++ b/arch/riscv/net/bpf_jit_comp64.c
@@ -2128,7 +2128,15 @@ bool bpf_jit_supports_ptr_xchg(void)
 
 bool bpf_jit_supports_arena(void)
 {
-	return true;
+	/*
+	 * The arena range tree uses kmalloc_nolock(), which needs
+	 * cmpxchg128, provided by ZACAS on riscv.
+	 */
+#ifdef system_has_cmpxchg128
+	return system_has_cmpxchg128();
+#else
+	return false;
+#endif
 }
 
 bool bpf_jit_supports_insn(struct bpf_insn *insn, bool in_arena)
diff --git a/arch/x86/net/bpf_jit_comp.c b/arch/x86/net/bpf_jit_comp.c
index 1a9fb530adc3..2853e87797a7 100644
--- a/arch/x86/net/bpf_jit_comp.c
+++ b/arch/x86/net/bpf_jit_comp.c
@@ -13,6 +13,7 @@
 #include <linux/bpf_verifier.h>
 #include <linux/memory.h>
 #include <linux/sort.h>
+#include <linux/execmem.h>
 #include <asm/extable.h>
 #include <asm/ftrace.h>
 #include <asm/set_memory.h>
@@ -3818,15 +3819,16 @@ int arch_bpf_trampoline_size(const struct btf_func_model *m, u32 flags,
 	 *
 	 * We cannot use kvmalloc here, because we need image to be in
 	 * module memory range.
-	 * Since it must be writable use bpf_jit_alloc_exec_rw().
+	 * Since it must be writable use execmem_alloc(EXECMEM_MODULE_DATA)
+	 * that returns writable memory in the module address space.
 	 */
-	image = bpf_jit_alloc_exec_rw(PAGE_SIZE);
+	image = execmem_alloc(EXECMEM_MODULE_DATA, PAGE_SIZE);
 	if (!image)
 		return -ENOMEM;
 
 	ret = __arch_prepare_bpf_trampoline(&im, image, image + PAGE_SIZE, image,
 					    m, flags, tnodes, func_addr);
-	bpf_jit_free_exec(image);
+	execmem_free(image);
 	return ret;
 }