+ mm-mremap-fix-sign-for-efault-error-return-value.patch added to -mm tree

+ mm-mremap-fix-sign-for-efault-error-return-value.patch added to -mm tree

[Andrew Morton]

The patch titled
     Subject: mm: mremap: fix sign for EFAULT error return value
has been added to the -mm tree.  Its filename is
     mm-mremap-fix-sign-for-efault-error-return-value.patch

This patch should soon appear at
    https://ozlabs.org/~akpm/mmots/broken-out/mm-mremap-fix-sign-for-efault-error-return-value.patch
and later at
    https://ozlabs.org/~akpm/mmotm/broken-out/mm-mremap-fix-sign-for-efault-error-return-value.patch

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------------------------------------------------------
From: Niels Dossche <dossche.niels@gmail.com>
Subject: mm: mremap: fix sign for EFAULT error return value

The mremap syscall is supposed to return a pointer to the new virtual
memory area on success, and a negative value of the error code in case of
failure.  Currently, EFAULT is returned when the VMA is not found, instead
of -EFAULT.  The users of this syscall will therefore believe the syscall
succeeded in case the VMA didn't exist, as it returns a pointer to address
0xe (0xe being the value of EFAULT).  Fix the sign of the error value.

Link: https://lkml.kernel.org/r/20220427224439.23828-2-dossche.niels@gmail.com
Fixes: 550a7d60bd5e ("mm, hugepages: add mremap() support for hugepage backed vma")
Signed-off-by: Niels Dossche <dossche.niels@gmail.com>
Cc: Mina Almasry <almasrymina@google.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/mremap.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/mm/mremap.c~mm-mremap-fix-sign-for-efault-error-return-value
+++ a/mm/mremap.c
@@ -941,7 +941,7 @@ SYSCALL_DEFINE5(mremap, unsigned long, a
 		return -EINTR;
 	vma = vma_lookup(mm, addr);
 	if (!vma) {
-		ret = EFAULT;
+		ret = -EFAULT;
 		goto out;
 	}
 
_

Patches currently in -mm which might be from dossche.niels@gmail.com are

mm-mremap-fix-sign-for-efault-error-return-value.patch