1 files changed, 26 insertions, 8 deletions

diff --git a/mm/mmap.c b/mm/mmap.c
index e780d19aa214..e6ee12344b13 100644
--- a/mm/mmap.c
+++ b/mm/mmap.c
@@ -121,14 +121,26 @@ int __vm_enough_memory(long pages, int cap_sys_admin)
                  * only call if we're about to fail.
                  */
                 n = nr_free_pages();
+
+                /*
+                 * Leave reserved pages. The pages are not for anonymous pages.
+                 */
+                if (n <= totalreserve_pages)
+                        goto error;
+                else
+                        n -= totalreserve_pages;
+
+                /*
+                 * Leave the last 3% for root
+                 */
                 if (!cap_sys_admin)
                         n -= n / 32;
                 free += n;
 
                 if (free > pages)
                         return 0;
-                vm_unacct_memory(pages);
-                return -ENOMEM;
+
+                goto error;
         }
 
         allowed = (totalram_pages - hugetlb_total_pages())
@@ -150,7 +162,7 @@ int __vm_enough_memory(long pages, int cap_sys_admin)
          */
         if (atomic_read(&vm_committed_space) < (long)allowed)
                 return 0;
-
+error:
         vm_unacct_memory(pages);
 
         return -ENOMEM;
@@ -220,6 +232,17 @@ asmlinkage unsigned long sys_brk(unsigned long brk)
 
         if (brk < mm->end_code)
                 goto out;
+
+        /*
+         * Check against rlimit here. If this check is done later after the test
+         * of oldbrk with newbrk then it can escape the test and let the data
+         * 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;
+        if (rlim < RLIM_INFINITY && brk - mm->start_data > rlim)
+                goto out;
+
         newbrk = PAGE_ALIGN(brk);
         oldbrk = PAGE_ALIGN(mm->brk);
         if (oldbrk == newbrk)
@@ -232,11 +255,6 @@ asmlinkage unsigned long sys_brk(unsigned long brk)
                 goto out;
         }
 
-        /* Check against rlimit.. */
-        rlim = current->signal->rlim[RLIMIT_DATA].rlim_cur;
-        if (rlim < RLIM_INFINITY && brk - mm->start_data > rlim)
-                goto out;
-
         /* Check against existing mmap mappings. */
         if (find_vma_intersection(mm, oldbrk, newbrk+PAGE_SIZE))
                 goto out;