+ mm-respect-arch_dup_mmap-return-value.patch added to -mm tree

+ mm-respect-arch_dup_mmap-return-value.patch added to -mm tree

[akpm]

The patch titled
     Subject: mm: respect arch_dup_mmap() return value
has been added to the -mm tree.  Its filename is
     mm-respect-arch_dup_mmap-return-value.patch

This patch should soon appear at
    http://ozlabs.org/~akpm/mmots/broken-out/mm-respect-arch_dup_mmap-return-value.patch
and later at
    http://ozlabs.org/~akpm/mmotm/broken-out/mm-respect-arch_dup_mmap-return-value.patch

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------------------------------------------------------
From: Nadav Amit <namit@vmware.com>
Subject: mm: respect arch_dup_mmap() return value

d70f2a14b72a4 ("include/linux/sched/mm.h: uninline mmdrop_async(), etc")
ignored the return value of arch_dup_mmap().  As a result, on x86, a
failure to duplicate the LDT (e.g., due to memory allocation error), would
leave the duplicated memory mapping in an inconsistent state.

Fix by regarding the return value, as it was before the change.

Link: http://lkml.kernel.org/r/20180823051229.211856-1-namit@vmware.com
Fixes: d70f2a14b72a4 ("include/linux/sched/mm.h: uninline mmdrop_async(), etc")
Signed-off-by: Nadav Amit <namit@vmware.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: <stable@vger.kernel.org>

Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 kernel/fork.c |    3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

--- a/kernel/fork.c~mm-respect-arch_dup_mmap-return-value
+++ a/kernel/fork.c
@@ -550,8 +550,7 @@ static __latent_entropy int dup_mmap(str
 			goto out;
 	}
 	/* a new mm has just been created */
-	arch_dup_mmap(oldmm, mm);
-	retval = 0;
+	retval = arch_dup_mmap(oldmm, mm);
 out:
 	up_write(&mm->mmap_sem);
 	flush_tlb_mm(oldmm);
_

Patches currently in -mm which might be from namit@vmware.com are

mm-respect-arch_dup_mmap-return-value.patch