4.18-stable review patch. If anyone has any objections, please let me know.
------------------ From: Nadav Amit <[email protected]> commit 1ed0cc5a01a4d868d9907ce96468c4b4c6709556 upstream. Commit d70f2a14b72a ("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/[email protected] Fixes: d70f2a14b72a4 ("include/linux/sched/mm.h: uninline mmdrop_async(), etc") Signed-off-by: Nadav Amit <[email protected]> Acked-by: Michal Hocko <[email protected]> Cc: <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]> --- kernel/fork.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) --- a/kernel/fork.c +++ b/kernel/fork.c @@ -549,8 +549,7 @@ 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);
