From 93ea1d0a12623dc1a693642b5758261f35f9bf96 Mon Sep 17 00:00:00 2001
From: Chris Wright <chrisw@osdl.org>
Date: Sun, 1 May 2005 08:58:38 -0700
Subject: [PATCH] [PATCH] RLIMIT_MEMLOCK checking fix
Always use page counts when doing RLIMIT_MEMLOCK checking to avoid possible
overflow.
Signed-off-by: Chris Wright <chrisw@osdl.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
---
mm/mmap.c | 10 ++++++----
1 file changed, 6 insertions(+), 4 deletions(-)
diff --git a/mm/mmap.c b/mm/mmap.c
index 1ec0f6e9c0d8..01f9793591f6 100644
--- a/mm/mmap.c
+++ b/mm/mmap.c
@@ -937,9 +937,10 @@ unsigned long do_mmap_pgoff(struct file * file, unsigned long addr,
/* mlock MCL_FUTURE? */
if (vm_flags & VM_LOCKED) {
unsigned long locked, lock_limit;
- locked = mm->locked_vm << PAGE_SHIFT;
+ locked = len >> PAGE_SHIFT;
+ locked += mm->locked_vm;
lock_limit = current->signal->rlim[RLIMIT_MEMLOCK].rlim_cur;
- locked += len;
+ lock_limit >>= PAGE_SHIFT;
if (locked > lock_limit && !capable(CAP_IPC_LOCK))
return -EAGAIN;
}
@@ -1822,9 +1823,10 @@ unsigned long do_brk(unsigned long addr, unsigned long len)
*/
if (mm->def_flags & VM_LOCKED) {
unsigned long locked, lock_limit;
- locked = mm->locked_vm << PAGE_SHIFT;
+ locked = len >> PAGE_SHIFT;
+ locked += mm->locked_vm;
lock_limit = current->signal->rlim[RLIMIT_MEMLOCK].rlim_cur;
- locked += len;
+ lock_limit >>= PAGE_SHIFT;
if (locked > lock_limit && !capable(CAP_IPC_LOCK))
return -EAGAIN;
}