---

yaml --- r: 143111 b: refs/heads/master c: 93cfb3c h: refs/heads/master i: 143109: 0076d71 143107: ec8c246 143103: 4075168 v: v3
git-mirror · Apr 10, 2009 · 66a73d4 · 66a73d4
1 parent 5a4ec3c
commit 66a73d4
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Showing 2 changed files with 15 additions and 3 deletions.
diff --git a/[refs] b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: c7625a555f55d7ae49236cde551786c88f5a5ce1
+refs/heads/master: 93cfb3c9fd83d877a8f1ffad9ff862b617b32828
diff --git a/trunk/kernel/trace/trace.c b/trunk/kernel/trace/trace.c
@@ -3428,7 +3428,19 @@ tracing_buffers_splice_read(struct file *file, loff_t *ppos,
 	int size, i;
 	size_t ret;
 
-	for (i = 0; i < PIPE_BUFFERS && len; i++, len -= size) {
+	if (*ppos & (PAGE_SIZE - 1)) {
+		WARN_ONCE(1, "Ftrace: previous read must page-align\n");
+		return -EINVAL;
+	}
+
+	if (len & (PAGE_SIZE - 1)) {
+		WARN_ONCE(1, "Ftrace: splice_read should page-align\n");
+		if (len < PAGE_SIZE)
+			return -EINVAL;
+		len &= PAGE_MASK;
+	}
+
+	for (i = 0; i < PIPE_BUFFERS && len; i++, len -= PAGE_SIZE) {
 		struct page *page;
 		int r;
 
@@ -3467,7 +3479,7 @@ tracing_buffers_splice_read(struct file *file, loff_t *ppos,
 		spd.partial[i].offset = 0;
 		spd.partial[i].private = (unsigned long)ref;
 		spd.nr_pages++;
-		*ppos += size;
+		*ppos += PAGE_SIZE;
 	}
 
 	spd.nr_pages = i;