android: binder: Rate-limit debug and userspace triggered err msgs

Use rate-limited debug messages where userspace can trigger
excessive log spams.

Acked-by: Arve Hjønnevåg <arve@android.com>
Signed-off-by: Sherry Yang <sherryy@android.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Change-Id: Ic789d9165479d56a9599ab016d38b07d2e0681a7

drivers/android/binder.c

@@ -71,6 +71,7 @@
 #include <linux/pid_namespace.h>
 #include <linux/security.h>
 #include <linux/spinlock.h>
+#include <linux/ratelimit.h>
 
 #include <uapi/linux/android/binder.h>
 #include <uapi/linux/sched/types.h>
@@ -150,13 +151,13 @@ module_param_call(stop_on_user_error, binder_set_stop_on_user_error,
 #define binder_debug(mask, x...) \
 	do { \
 		if (binder_debug_mask & mask) \
-			pr_info(x); \
+			pr_info_ratelimited(x); \
 	} while (0)
 
 #define binder_user_error(x...) \
 	do { \
 		if (binder_debug_mask & BINDER_DEBUG_USER_ERROR) \
-			pr_info(x); \
+			pr_info_ratelimited(x); \
 		if (binder_stop_on_user_error) \
 			binder_stop_on_user_error = 2; \
 	} while (0)

drivers/android/binder_alloc.c

@@ -30,6 +30,7 @@
 #include <linux/list_lru.h>
 #include <linux/uaccess.h>
 #include <linux/highmem.h>
+#include <linux/ratelimit.h>
 #include "binder_alloc.h"
 #include "binder_trace.h"
 
@@ -43,7 +44,7 @@ enum {
 	BINDER_DEBUG_BUFFER_ALLOC           = 1U << 2,
 	BINDER_DEBUG_BUFFER_ALLOC_ASYNC     = 1U << 3,
 };
-static uint32_t binder_alloc_debug_mask;
+static uint32_t binder_alloc_debug_mask = BINDER_DEBUG_USER_ERROR;
 
 module_param_named(debug_mask, binder_alloc_debug_mask,
 		   uint, 0644);
@@ -51,7 +52,7 @@ module_param_named(debug_mask, binder_alloc_debug_mask,
 #define binder_alloc_debug(mask, x...) \
 	do { \
 		if (binder_alloc_debug_mask & mask) \
-			pr_info(x); \
+			pr_info_ratelimited(x); \
 	} while (0)
 
 static struct binder_buffer *binder_buffer_next(struct binder_buffer *buffer)
@@ -224,8 +225,9 @@ static int binder_update_page_range(struct binder_alloc *alloc, int allocate,
 	}
 
 	if (!vma && need_mm) {
-		pr_err("%d: binder_alloc_buf failed to map pages in userspace, no vma\n",
-			alloc->pid);
+		binder_alloc_debug(BINDER_DEBUG_USER_ERROR,
+				   "%d: binder_alloc_buf failed to map pages in userspace, no vma\n",
+				   alloc->pid);
 		goto err_no_vma;
 	}
 
@@ -405,8 +407,9 @@ static struct binder_buffer *binder_alloc_new_buf_locked(
 	int ret;
 
 	if (!binder_alloc_get_vma(alloc)) {
-		pr_err("%d: binder_alloc_buf, no vma\n",
-		       alloc->pid);
+		binder_alloc_debug(BINDER_DEBUG_USER_ERROR,
+				   "%d: binder_alloc_buf, no vma\n",
+				   alloc->pid);
 		return ERR_PTR(-ESRCH);
 	}
 
@@ -478,11 +481,14 @@ static struct binder_buffer *binder_alloc_new_buf_locked(
 			if (buffer_size > largest_free_size)
 				largest_free_size = buffer_size;
 		}
-		pr_err("%d: binder_alloc_buf size %zd failed, no address space\n",
-			alloc->pid, size);
-		pr_err("allocated: %zd (num: %zd largest: %zd), free: %zd (num: %zd largest: %zd)\n",
-		       total_alloc_size, allocated_buffers, largest_alloc_size,
-		       total_free_size, free_buffers, largest_free_size);
+		binder_alloc_debug(BINDER_DEBUG_USER_ERROR,
+				   "%d: binder_alloc_buf size %zd failed, no address space\n",
+				   alloc->pid, size);
+		binder_alloc_debug(BINDER_DEBUG_USER_ERROR,
+				   "allocated: %zd (num: %zd largest: %zd), free: %zd (num: %zd largest: %zd)\n",
+				   total_alloc_size, allocated_buffers,
+				   largest_alloc_size, total_free_size,
+				   free_buffers, largest_free_size);
 		return ERR_PTR(-ENOSPC);
 	}
 	if (n == NULL) {
@@ -800,8 +806,10 @@ err_alloc_pages_failed:
 	alloc->buffer = NULL;
 err_already_mapped:
 	mutex_unlock(&binder_alloc_mmap_lock);
-	pr_err("%s: %d %lx-%lx %s failed %d\n", __func__,
-	       alloc->pid, vma->vm_start, vma->vm_end, failure_string, ret);
+	binder_alloc_debug(BINDER_DEBUG_USER_ERROR,
+			   "%s: %d %lx-%lx %s failed %d\n", __func__,
+			   alloc->pid, vma->vm_start, vma->vm_end,
+			   failure_string, ret);
 	return ret;
 }