From: Arve Hjønnevåg <arve@android.com>
Date: Tue, 15 Apr 2008 04:35:25 +0000 (-0700)
Subject: printk: Fix log_buf_copy termination.
X-Git-Tag: firefly_0821_release~7613^2~774
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=0da19af0b8c8b8d8bd19a262479d49d8061c0c13;p=firefly-linux-kernel-4.4.55.git

printk: Fix log_buf_copy termination.

If idx was non-zero and the log had wrapped, len did not get truncated
to stop at the last byte written to the log.
---

diff --git a/kernel/printk.c b/kernel/printk.c
index c78ed88446d6..cd8fbf3440a8 100644
--- a/kernel/printk.c
+++ b/kernel/printk.c
@@ -319,8 +319,8 @@ int log_buf_copy(char *dest, int idx, int len)
 	if (idx < 0 || idx >= max) {
 		ret = -1;
 	} else {
-		if (len > max)
-			len = max;
+		if (len > max - idx)
+			len = max - idx;
 		ret = len;
 		idx += (log_end - max);
 		while (len-- > 0)