From: Nadav Amit <namit@xxxxxxxxxx>
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@xxxxxxxxxx
Fixes: d70f2a14b72a4 ("include/linux/sched/mm.h: uninline mmdrop_async(), etc")
Signed-off-by: Nadav Amit <namit@xxxxxxxxxx>
Acked-by: Michal Hocko <mhocko@xxxxxxxx>
Cc: <stable@xxxxxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
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);
_
