+ mm-selftests-for-exclusive-device-memory-fix.patch added to -mm tree

+ mm-selftests-for-exclusive-device-memory-fix.patch added to -mm tree

[akpm]

The patch titled
     Subject: mm: selftests: fix potential integer overflow on shift of a int
has been added to the -mm tree.  Its filename is
     mm-selftests-for-exclusive-device-memory-fix.patch

This patch should soon appear at
    https://ozlabs.org/~akpm/mmots/broken-out/mm-selftests-for-exclusive-device-memory-fix.patch
and later at
    https://ozlabs.org/~akpm/mmotm/broken-out/mm-selftests-for-exclusive-device-memory-fix.patch

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------------------------------------------------------
From: Colin Ian King <colin.king@canonical.com>
Subject: mm: selftests: fix potential integer overflow on shift of a int

The left shift of the int mapped is evaluated using 32 bit arithmetic and
then assigned to an unsigned long.  In the case where mapped is 0x80000
when PAGE_SHIFT is 12 will lead to the upper bits being sign extended in
the unsigned long.  Larger values can lead to an int overflow.  Avoid this
by making mapped an unsigned long.

Addresses-Coverity: ("Uninitentional integer overflow")
Link: https://lkml.kernel.org/r/20210526170530.3766167-1-colin.king@canonical.com
Fixes: 8b2a105c3794 ("mm: selftests for exclusive device memory")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Cc: Alistair Popple <apopple@nvidia.com>
Cc: Jason Gunthorpe <jgg@nvidia.com>
Cc: Ralph Campbell <rcampbell@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 lib/test_hmm.c |    3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

--- a/lib/test_hmm.c~mm-selftests-for-exclusive-device-memory-fix
+++ a/lib/test_hmm.c
@@ -733,7 +733,8 @@ static int dmirror_exclusive(struct dmir
 
 	mmap_read_lock(mm);
 	for (addr = start; addr < end; addr = next) {
-		int i, mapped;
+		unsigned long mapped;
+		int i;
 
 		if (end < addr + (ARRAY_SIZE(pages) << PAGE_SHIFT))
 			next = end;
_

Patches currently in -mm which might be from colin.king@canonical.com are

scripts-spellingtxt-add-more-spellings-to-spellingtxt.patch
ocfs2-remove-redundant-assignment-to-pointer-queue.patch
mm-selftests-for-exclusive-device-memory-fix.patch