mm: use rlimit helpers
Make sure compiler won't do weird things with limits. E.g. fetching them
twice may return 2 different values after writable limits are implemented.
I.e. either use rlimit helpers added in
3e10e716abf3c71bdb5d86b8f507f9e72236c9cd ("resource: add helpers for
fetching rlimits") or ACCESS_ONCE if not applicable.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/mm/mmap.c b/mm/mmap.c
index c646618..3165614 100644
--- a/mm/mmap.c
+++ b/mm/mmap.c
@@ -265,7 +265,7 @@
* segment grow beyond its set limit the in case where the limit is
* not page aligned -Ram Gupta
*/
- rlim = current->signal->rlim[RLIMIT_DATA].rlim_cur;
+ rlim = rlimit(RLIMIT_DATA);
if (rlim < RLIM_INFINITY && (brk - mm->start_brk) +
(mm->end_data - mm->start_data) > rlim)
goto out;
@@ -967,7 +967,7 @@
unsigned long locked, lock_limit;
locked = len >> PAGE_SHIFT;
locked += mm->locked_vm;
- lock_limit = current->signal->rlim[RLIMIT_MEMLOCK].rlim_cur;
+ lock_limit = rlimit(RLIMIT_MEMLOCK);
lock_limit >>= PAGE_SHIFT;
if (locked > lock_limit && !capable(CAP_IPC_LOCK))
return -EAGAIN;
@@ -1594,7 +1594,7 @@
return -ENOMEM;
/* Stack limit test */
- if (size > rlim[RLIMIT_STACK].rlim_cur)
+ if (size > ACCESS_ONCE(rlim[RLIMIT_STACK].rlim_cur))
return -ENOMEM;
/* mlock limit tests */
@@ -1602,7 +1602,8 @@
unsigned long locked;
unsigned long limit;
locked = mm->locked_vm + grow;
- limit = rlim[RLIMIT_MEMLOCK].rlim_cur >> PAGE_SHIFT;
+ limit = ACCESS_ONCE(rlim[RLIMIT_MEMLOCK].rlim_cur);
+ limit >>= PAGE_SHIFT;
if (locked > limit && !capable(CAP_IPC_LOCK))
return -ENOMEM;
}
@@ -2067,7 +2068,7 @@
unsigned long locked, lock_limit;
locked = len >> PAGE_SHIFT;
locked += mm->locked_vm;
- lock_limit = current->signal->rlim[RLIMIT_MEMLOCK].rlim_cur;
+ lock_limit = rlimit(RLIMIT_MEMLOCK);
lock_limit >>= PAGE_SHIFT;
if (locked > lock_limit && !capable(CAP_IPC_LOCK))
return -EAGAIN;
@@ -2281,7 +2282,7 @@
unsigned long cur = mm->total_vm; /* pages */
unsigned long lim;
- lim = current->signal->rlim[RLIMIT_AS].rlim_cur >> PAGE_SHIFT;
+ lim = rlimit(RLIMIT_AS) >> PAGE_SHIFT;
if (cur + npages > lim)
return 0;