Merge tag 'v4.17-rc4' into patchwork

Linux 4.17-rc4

* tag 'v4.17-rc4': (920 commits)
  Linux 4.17-rc4
  KVM: x86: remove APIC Timer periodic/oneshot spikes
  genksyms: fix typo in parse.tab.{c,h} generation rules
  kbuild: replace hardcoded bison in cmd_bison_h with $(YACC)
  gcc-plugins: fix build condition of SANCOV plugin
  MAINTAINERS: Update Kbuild entry with a few paths
  Revert "usb: host: ehci: Use dma_pool_zalloc()"
  platform/x86: Kconfig: Fix dell-laptop dependency chain.
  platform/x86: asus-wireless: Fix NULL pointer dereference
  arm64: vgic-v2: Fix proxying of cpuif access
  KVM: arm/arm64: vgic_init: Cleanup reference to process_maintenance
  KVM: arm64: Fix order of vcpu_write_sys_reg() arguments
  MAINTAINERS & files: Canonize the e-mails I use at files
  media: imx-media-csi: Fix inconsistent IS_ERR and PTR_ERR
  tools: power/acpi, revert to LD = gcc
  bdi: Fix oops in wb_workfn()
  RDMA/cma: Do not query GID during QP state transition to RTR
  IB/mlx4: Fix integer overflow when calculating optimal MTT size
  IB/hfi1: Fix memory leak in exception path in get_irq_affinity()
  IB/{hfi1, rdmavt}: Fix memory leak in hfi1_alloc_devdata() upon failure
  ...

1 files changed, 29 insertions, 16 deletions

diff --git a/kernel/bpf/core.c b/kernel/bpf/core.c
index d315b393abdd..ba03ec39efb3 100644
--- a/kernel/bpf/core.c
+++ b/kernel/bpf/core.c
@@ -1572,13 +1572,32 @@ int bpf_prog_array_length(struct bpf_prog_array __rcu *progs)
 	return cnt;
 }
 
+static bool bpf_prog_array_copy_core(struct bpf_prog **prog,
+				     u32 *prog_ids,
+				     u32 request_cnt)
+{
+	int i = 0;
+
+	for (; *prog; prog++) {
+		if (*prog == &dummy_bpf_prog.prog)
+			continue;
+		prog_ids[i] = (*prog)->aux->id;
+		if (++i == request_cnt) {
+			prog++;
+			break;
+		}
+	}
+
+	return !!(*prog);
+}
+
 int bpf_prog_array_copy_to_user(struct bpf_prog_array __rcu *progs,
 				__u32 __user *prog_ids, u32 cnt)
 {
 	struct bpf_prog **prog;
 	unsigned long err = 0;
-	u32 i = 0, *ids;
 	bool nospc;
+	u32 *ids;
 
 	/* users of this function are doing:
 	 * cnt = bpf_prog_array_length();
@@ -1595,16 +1614,7 @@ int bpf_prog_array_copy_to_user(struct bpf_prog_array __rcu *progs,
 		return -ENOMEM;
 	rcu_read_lock();
 	prog = rcu_dereference(progs)->progs;
-	for (; *prog; prog++) {
-		if (*prog == &dummy_bpf_prog.prog)
-			continue;
-		ids[i] = (*prog)->aux->id;
-		if (++i == cnt) {
-			prog++;
-			break;
-		}
-	}
-	nospc = !!(*prog);
+	nospc = bpf_prog_array_copy_core(prog, ids, cnt);
 	rcu_read_unlock();
 	err = copy_to_user(prog_ids, ids, cnt * sizeof(u32));
 	kfree(ids);
@@ -1683,22 +1693,25 @@ int bpf_prog_array_copy(struct bpf_prog_array __rcu *old_array,
 }
 
 int bpf_prog_array_copy_info(struct bpf_prog_array __rcu *array,
-			     __u32 __user *prog_ids, u32 request_cnt,
-			     __u32 __user *prog_cnt)
+			     u32 *prog_ids, u32 request_cnt,
+			     u32 *prog_cnt)
 {
+	struct bpf_prog **prog;
 	u32 cnt = 0;
 
 	if (array)
 		cnt = bpf_prog_array_length(array);
 
-	if (copy_to_user(prog_cnt, &cnt, sizeof(cnt)))
-		return -EFAULT;
+	*prog_cnt = cnt;
 
 	/* return early if user requested only program count or nothing to copy */
 	if (!request_cnt || !cnt)
 		return 0;
 
-	return bpf_prog_array_copy_to_user(array, prog_ids, request_cnt);
+	/* this function is called under trace/bpf_trace.c: bpf_event_mutex */
+	prog = rcu_dereference_check(array, 1)->progs;
+	return bpf_prog_array_copy_core(prog, prog_ids, request_cnt) ? -ENOSPC
+								     : 0;
 }
 
 static void bpf_prog_free_deferred(struct work_struct *work)