From: Jeremy Compostella <jeremy.compostella@intel.com>
Date: Mon, 2 May 2016 15:29:28 +0000 (+0200)
Subject: ANDROID: dm: fix dm_substitute_devices()
X-Git-Tag: firefly_0821_release~176^2~352
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=b8681ffa6859d3f267d625d4770987df5832a42b;p=firefly-linux-kernel-4.4.55.git

ANDROID: dm: fix dm_substitute_devices()

When candidate is the last parameter, candidate_end points to the '\0'
character and not the DM_FIELD_SEP character.  In such a situation, we
should not move the candidate_end pointer one character backward.

Signed-off-by: Jeremy Compostella <jeremy.compostella@intel.com>
---

diff --git a/init/do_mounts_dm.c b/init/do_mounts_dm.c
index f521bc5ae248..ecda58df9a19 100644
--- a/init/do_mounts_dm.c
+++ b/init/do_mounts_dm.c
@@ -176,7 +176,8 @@ static void __init dm_substitute_devices(char *str, size_t str_len)
 			continue;
 
 		/* Temporarily terminate with a nul */
-		candidate_end--;
+		if (*candidate_end)
+			candidate_end--;
 		old_char = *candidate_end;
 		*candidate_end = '\0';