mm: replace access_process_vm() write parameter with gup_flags
This removes the 'write' argument from access_process_vm() and replaces
it with 'gup_flags' as use of this function previously silently implied
FOLL_FORCE, whereas after this patch callers explicitly pass this flag.
We make this explicit as use of FOLL_FORCE can result in surprising
behaviour (and hence bugs) within the mm subsystem.
Signed-off-by: Lorenzo Stoakes <lstoakes@gmail.com>
Acked-by: Jesper Nilsson <jesper.nilsson@axis.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/mm/util.c b/mm/util.c
index 4c685bd..952cbe7 100644
--- a/mm/util.c
+++ b/mm/util.c
@@ -624,7 +624,7 @@
if (len > buflen)
len = buflen;
- res = access_process_vm(task, arg_start, buffer, len, 0);
+ res = access_process_vm(task, arg_start, buffer, len, FOLL_FORCE);
/*
* If the nul at the end of args has been overwritten, then
@@ -639,7 +639,8 @@
if (len > buflen - res)
len = buflen - res;
res += access_process_vm(task, env_start,
- buffer+res, len, 0);
+ buffer+res, len,
+ FOLL_FORCE);
res = strnlen(buffer, res);
}
}