From: Eric Biggers <ebiggers@google.com>
Date: Thu, 23 Mar 2023 00:44:21 +0000 (+0000)
Subject: AOSP: ext2simg: fix same_file() to check st_dev
X-Git-Tag: v1.47.1-wc1~116
X-Git-Url: https://git.whamcloud.com/?a=commitdiff_plain;h=eb6c137c51dcda142637981413e9a45da81b34e9;p=tools%2Fe2fsprogs.git

AOSP: ext2simg: fix same_file() to check st_dev

File identity is determined by the combination of st_dev and st_ino, not
by st_ino alone.

This fixes a bug where ext2simg would needlessly make a copy of all the
data when the input and output files happened to have the same st_ino.

Fixes: db6f320912cf ("AOSP: android: add the ext2simg tool")
Change-Id: I94e4bf57d9f91b31e5438768805e9f10bec3411d
Signed-off-by: Eric Biggers <ebiggers@google.com>
From AOSP commit: 0749f83a2cf4c134a2403701ab78388500e53f76
---

diff --git a/contrib/android/ext2simg.c b/contrib/android/ext2simg.c
index 9ef54cf..1bc2308 100644
--- a/contrib/android/ext2simg.c
+++ b/contrib/android/ext2simg.c
@@ -189,7 +189,7 @@ static bool same_file(const char *in, const char *out)
 		ext2fs_fatal(errno, "stat %s\n", in);
 	if (lstat(out, &st2) == -1)
 		ext2fs_fatal(errno, "stat %s\n", out);
-	return st1.st_ino == st2.st_ino;
+	return st1.st_dev == st2.st_dev && st1.st_ino == st2.st_ino;
 }
 
 int main(int argc, char *argv[])