ipc,shm: cleanup do_shmat pasta
Davidlohr Bueso [Wed, 11 Sep 2013 21:26:22 +0000 (14:26 -0700)]
commit f42569b1388b1408b574a5e93a23a663647d4181 upstream.

Clean up some of the messy do_shmat() spaghetti code, getting rid of
out_free and out_put_dentry labels.  This makes shortening the critical
region of this function in the next patch a little easier to do and read.

Signed-off-by: Davidlohr Bueso <davidlohr.bueso@hp.com>
Tested-by: Sedat Dilek <sedat.dilek@gmail.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Manfred Spraul <manfred@colorfullife.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

ipc/shm.c

index a204d0b..1eeef9f 100644 (file)
--- a/ipc/shm.c
+++ b/ipc/shm.c
@@ -1108,16 +1108,21 @@ long do_shmat(int shmid, char __user *shmaddr, int shmflg, ulong *raddr,
 
        err = -ENOMEM;
        sfd = kzalloc(sizeof(*sfd), GFP_KERNEL);
-       if (!sfd)
-               goto out_put_dentry;
+       if (!sfd) {
+               path_put(&path);
+               goto out_nattch;
+       }
 
        file = alloc_file(&path, f_mode,
                          is_file_hugepages(shp->shm_file) ?
                                &shm_file_operations_huge :
                                &shm_file_operations);
        err = PTR_ERR(file);
-       if (IS_ERR(file))
-               goto out_free;
+       if (IS_ERR(file)) {
+               kfree(sfd);
+               path_put(&path);
+               goto out_nattch;
+       }
 
        file->private_data = sfd;
        file->f_mapping = shp->shm_file->f_mapping;
@@ -1143,7 +1148,7 @@ long do_shmat(int shmid, char __user *shmaddr, int shmflg, ulong *raddr,
                    addr > current->mm->start_stack - size - PAGE_SIZE * 5)
                        goto invalid;
        }
-               
+
        addr = do_mmap_pgoff(file, addr, size, prot, flags, 0, &populate);
        *raddr = addr;
        err = 0;
@@ -1167,19 +1172,12 @@ out_nattch:
        else
                shm_unlock(shp);
        up_write(&shm_ids(ns).rw_mutex);
-
-out:
        return err;
 
 out_unlock:
        shm_unlock(shp);
-       goto out;
-
-out_free:
-       kfree(sfd);
-out_put_dentry:
-       path_put(&path);
-       goto out_nattch;
+out:
+       return err;
 }
 
 SYSCALL_DEFINE3(shmat, int, shmid, char __user *, shmaddr, int, shmflg)