[3.19.y-ckt stable] Patch "scripts: recordmcount: break hardlinks" has been added to the 3.19.y-ckt tree

[Kamal Mostafa]

This is a note to let you know that I have just added a patch titled

    scripts: recordmcount: break hardlinks

to the linux-3.19.y-queue branch of the 3.19.y-ckt extended stable tree 
which can be found at:

    http://kernel.ubuntu.com/git/ubuntu/linux.git/log/?h=linux-3.19.y-queue

This patch is scheduled to be released in version 3.19.8-ckt13.

If you, or anyone else, feels it should not be added to this tree, please 
reply to this email.

For more information about the 3.19.y-ckt tree, see
https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable

Thanks.
-Kamal

---8<------------------------------------------------------------

>From 33debb3fcb31ba1e2217759188f25837c11d88d3 Mon Sep 17 00:00:00 2001
From: Russell King <rmk+kernel at arm.linux.org.uk>
Date: Fri, 11 Dec 2015 12:09:03 +0000
Subject: scripts: recordmcount: break hardlinks

commit dd39a26538e37f6c6131e829a4a510787e43c783 upstream.

recordmcount edits the file in-place, which can cause problems when
using ccache in hardlink mode.  Arrange for recordmcount to break a
hardlinked object.

Link: http://lkml.kernel.org/r/E1a7MVT-0000et-62@rmk-PC.arm.linux.org.uk

Signed-off-by: Russell King <rmk+kernel at arm.linux.org.uk>
Signed-off-by: Steven Rostedt <rostedt at goodmis.org>
Signed-off-by: Kamal Mostafa <kamal at canonical.com>
---
 scripts/recordmcount.c | 14 ++++++++++++++
 1 file changed, 14 insertions(+)

diff --git a/scripts/recordmcount.c b/scripts/recordmcount.c
index e00bcd1..fd42629 100644
--- a/scripts/recordmcount.c
+++ b/scripts/recordmcount.c
@@ -211,6 +211,20 @@ static void *mmap_file(char const *fname)
 		addr = umalloc(sb.st_size);
 		uread(fd_map, addr, sb.st_size);
 	}
+	if (sb.st_nlink != 1) {
+		/* file is hard-linked, break the hard link */
+		close(fd_map);
+		if (unlink(fname) < 0) {
+			perror(fname);
+			fail_file();
+		}
+		fd_map = open(fname, O_RDWR | O_CREAT, sb.st_mode);
+		if (fd_map < 0) {
+			perror(fname);
+			fail_file();
+		}
+		uwrite(fd_map, addr, sb.st_size);
+	}
 	return addr;
 }

--
1.9.1