[merged mm-nonmm-stable] block-partitions-ldm-convert-strncpy-to-strscpy.patch removed from -mm tree

[merged mm-nonmm-stable] block-partitions-ldm-convert-strncpy-to-strscpy.patch removed from -mm tree

[Andrew Morton]

The quilt patch titled
     Subject: block/partitions/ldm: convert strncpy() to strscpy()
has been removed from the -mm tree.  Its filename was
     block-partitions-ldm-convert-strncpy-to-strscpy.patch

This patch was dropped because it was merged into the mm-nonmm-stable branch
of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

------------------------------------------------------
From: Arnd Bergmann <arnd@arndb.de>
Subject: block/partitions/ldm: convert strncpy() to strscpy()
Date: Tue, 9 Apr 2024 16:00:56 +0200

The strncpy() here can cause a non-terminated string, which older gcc
versions such as gcc-9 warn about:

In function 'ldm_parse_tocblock',
    inlined from 'ldm_validate_tocblocks' at block/partitions/ldm.c:386:7,
    inlined from 'ldm_partition' at block/partitions/ldm.c:1457:7:
block/partitions/ldm.c:134:2: error: 'strncpy' specified bound 16 equals destination size [-Werror=stringop-truncation]
  134 |  strncpy (toc->bitmap1_name, data + 0x24, sizeof (toc->bitmap1_name));
      |  ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
block/partitions/ldm.c:145:2: error: 'strncpy' specified bound 16 equals destination size [-Werror=stringop-truncation]
  145 |  strncpy (toc->bitmap2_name, data + 0x46, sizeof (toc->bitmap2_name));
      |  ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

New versions notice that the code is correct after all because of the
following termination, but replacing the strncpy() with strscpy_pad()
or strcpy() avoids the warning and simplifies the code at the same time.

Use the padding version here to keep the existing behavior, in case
the code relies on not including uninitialized data.

Link: https://lkml.kernel.org/r/20240409140059.3806717-4-arnd@kernel.org
Reviewed-by: Justin Stitt <justinstitt@google.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Alexey Starikovskiy <astarikovskiy@suse.de>
Cc: Bob Moore <robert.moore@intel.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Len Brown <lenb@kernel.org>
Cc: Lin Ming <ming.m.lin@intel.com>
Cc: Masahiro Yamada <masahiroy@kernel.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Nathan Chancellor <nathan@kernel.org>
Cc: Nicolas Schier <nicolas@fjasle.eu>
Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: "Richard Russon (FlatCap)" <ldm@flatcap.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 block/partitions/ldm.c |    6 ++----
 1 file changed, 2 insertions(+), 4 deletions(-)

--- a/block/partitions/ldm.c~block-partitions-ldm-convert-strncpy-to-strscpy
+++ a/block/partitions/ldm.c
@@ -131,8 +131,7 @@ static bool ldm_parse_tocblock (const u8
 		ldm_crit ("Cannot find TOCBLOCK, database may be corrupt.");
 		return false;
 	}
-	strncpy (toc->bitmap1_name, data + 0x24, sizeof (toc->bitmap1_name));
-	toc->bitmap1_name[sizeof (toc->bitmap1_name) - 1] = 0;
+	strscpy_pad(toc->bitmap1_name, data + 0x24, sizeof(toc->bitmap1_name));
 	toc->bitmap1_start = get_unaligned_be64(data + 0x2E);
 	toc->bitmap1_size  = get_unaligned_be64(data + 0x36);
 
@@ -142,8 +141,7 @@ static bool ldm_parse_tocblock (const u8
 				TOC_BITMAP1, toc->bitmap1_name);
 		return false;
 	}
-	strncpy (toc->bitmap2_name, data + 0x46, sizeof (toc->bitmap2_name));
-	toc->bitmap2_name[sizeof (toc->bitmap2_name) - 1] = 0;
+	strscpy_pad(toc->bitmap2_name, data + 0x46, sizeof(toc->bitmap2_name));
 	toc->bitmap2_start = get_unaligned_be64(data + 0x50);
 	toc->bitmap2_size  = get_unaligned_be64(data + 0x58);
 	if (strncmp (toc->bitmap2_name, TOC_BITMAP2,
_

Patches currently in -mm which might be from arnd@arndb.de are

kbuild-turn-on-wextra-by-default.patch
kbuild-remove-redundant-extra-warning-flags.patch
kbuild-turn-on-wrestrict-by-default.patch
kbuild-enable-wformat-truncation-on-clang.patch
kbuild-enable-wcast-function-type-strict-unconditionally.patch