shmem: fix double uncharge in __shmem_file_setup()

If __shmem_file_setup() fails on struct file allocation it uncharges
memory commitment twice: first by shmem_unacct_size() and second time
implicitly in shmem_evict_inode() when it kills the newly created inode.

This patch removes shmem_unacct_size() from error path if the inode was
already there.

Signed-off-by: Konstantin Khlebnikov <koct9i@gmail.com>
Acked-by: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 6 insertions, 6 deletions

diff --git a/mm/shmem.c b/mm/shmem.c
index af68b15a8fc1..3609d31ad0dd 100644
--- a/mm/shmem.c
+++ b/mm/shmem.c
@@ -2932,16 +2932,16 @@ static struct file *__shmem_file_setup(const char *name, loff_t size,
         this.len = strlen(name);
         this.hash = 0; /* will go */
         sb = shm_mnt->mnt_sb;
+        path.mnt = mntget(shm_mnt);
         path.dentry = d_alloc_pseudo(sb, &this);
         if (!path.dentry)
                 goto put_memory;
         d_set_d_op(path.dentry, &anon_ops);
-        path.mnt = mntget(shm_mnt);
 
         res = ERR_PTR(-ENOSPC);
         inode = shmem_get_inode(sb, NULL, S_IFREG | S_IRWXUGO, 0, flags);
         if (!inode)
-                goto put_dentry;
+                goto put_memory;
 
         inode->i_flags |= i_flags;
         d_instantiate(path.dentry, inode);
@@ -2949,19 +2949,19 @@ static struct file *__shmem_file_setup(const char *name, loff_t size,
         clear_nlink(inode);     /* It is unlinked */
         res = ERR_PTR(ramfs_nommu_expand_for_mapping(inode, size));
         if (IS_ERR(res))
-                goto put_dentry;
+                goto put_path;
 
         res = alloc_file(&path, FMODE_WRITE | FMODE_READ,
                   &shmem_file_operations);
         if (IS_ERR(res))
-                goto put_dentry;
+                goto put_path;
 
         return res;
 
-put_dentry:
-        path_put(&path);
 put_memory:
         shmem_unacct_size(flags, size);
+put_path:
+        path_put(&path);
         return res;
 }