mm: respect arch_dup_mmap() return value

Commit d70f2a14b7 ("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 using the return value, as it was before the change.

Link: http://lkml.kernel.org/r/20180823051229.211856-1-namit@vmware.com
Fixes: d70f2a14b7 ("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>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Nadav Amit 2018-09-04 15:45:41 -07:00 committed by Linus Torvalds
parent 79cc81057e
commit 1ed0cc5a01

View file

@ -550,8 +550,7 @@ static __latent_entropy int dup_mmap(struct mm_struct *mm,
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);