1 files changed, 24 insertions, 7 deletions

diff --git a/fs/binfmt_flat.c b/fs/binfmt_flat.c
index ae8595d49856..7b0265d7f3a8 100644
--- a/fs/binfmt_flat.c
+++ b/fs/binfmt_flat.c
@@ -419,7 +419,7 @@ static int load_flat_file(struct linux_binprm * bprm,
         unsigned long textpos = 0, datapos = 0, result;
         unsigned long realdatastart = 0;
         unsigned long text_len, data_len, bss_len, stack_len, flags;
-        unsigned long memp = 0; /* for finding the brk area */
+        unsigned long len, reallen, memp = 0;
         unsigned long extra, rlim;
         unsigned long *reloc = 0, *rp;
         struct inode *inode;
@@ -540,10 +540,18 @@ static int load_flat_file(struct linux_binprm * bprm,
                         goto err;
                 }
 
+                len = data_len + extra + MAX_SHARED_LIBS * sizeof(unsigned long);
                 down_write(&current->mm->mmap_sem);
-                realdatastart = do_mmap(0, 0, data_len + extra +
-                                MAX_SHARED_LIBS * sizeof(unsigned long),
-                                PROT_READ|PROT_WRITE|PROT_EXEC, MAP_PRIVATE, 0);
+                realdatastart = do_mmap(0, 0, len,
+                        PROT_READ|PROT_WRITE|PROT_EXEC, MAP_PRIVATE, 0);
+                /* Remap to use all availabe slack region space */
+                if (realdatastart && (realdatastart < (unsigned long)-4096)) {
+                        reallen = ksize(realdatastart);
+                        if (reallen > len) {
+                                realdatastart = do_mremap(realdatastart, len,
+                                        reallen, MREMAP_FIXED, realdatastart);
+                        }
+                }
                 up_write(&current->mm->mmap_sem);
 
                 if (realdatastart == 0 || realdatastart >= (unsigned long)-4096) {
@@ -584,11 +592,20 @@ static int load_flat_file(struct linux_binprm * bprm,
 
         } else {
 
+                len = text_len + data_len + extra + MAX_SHARED_LIBS * sizeof(unsigned long);
                 down_write(&current->mm->mmap_sem);
-                textpos = do_mmap(0, 0, text_len + data_len + extra +
-                                        MAX_SHARED_LIBS * sizeof(unsigned long),
-                                PROT_READ | PROT_EXEC | PROT_WRITE, MAP_PRIVATE, 0);
+                textpos = do_mmap(0, 0, len,
+                        PROT_READ | PROT_EXEC | PROT_WRITE, MAP_PRIVATE, 0);
+                /* Remap to use all availabe slack region space */
+                if (textpos && (textpos < (unsigned long) -4096)) {
+                        reallen = ksize(textpos);
+                        if (reallen > len) {
+                                textpos = do_mremap(textpos, len, reallen,
+                                        MREMAP_FIXED, textpos);
+                        }
+                }
                 up_write(&current->mm->mmap_sem);
+
                 if (!textpos  || textpos >= (unsigned long) -4096) {
                         if (!textpos)
                                 textpos = (unsigned long) -ENOMEM;