tunnels: do not assume mac header is set in skb_tunnel_check_pmtu()

[mirror_ubuntu-jammy-kernel.git] / fs / overlayfs / file.c

diff --git a/fs/overlayfs/file.c b/fs/overlayfs/file.c
index c88ac571593dc1924e9ea0fbf3ab5aeaa588a69f..2e4ebebdb7d12fb425a11c4f21b8ec396e61331e 100644 (file)
--- a/fs/overlayfs/file.c
+++ b/fs/overlayfs/file.c
@@ -17,6 +17,7 @@
 
 struct ovl_aio_req {
        struct kiocb iocb;
+       refcount_t ref;
        struct kiocb *orig_iocb;
        struct fd fd;
 };
@@ -39,6 +40,7 @@ static char ovl_whatisit(struct inode *inode, struct inode *realinode)
 static struct file *ovl_open_realfile(const struct file *file,
                                      struct inode *realinode)
 {
+       struct path realpath;
        struct inode *inode = file_inode(file);
        struct file *realfile;
        const struct cred *old_cred;
@@ -57,7 +59,8 @@ static struct file *ovl_open_realfile(const struct file *file,
                if (!inode_owner_or_capable(&init_user_ns, realinode))
                        flags &= ~O_NOATIME;
 
-               realfile = open_with_fake_path(&file->f_path, flags, realinode,
+               ovl_path_real(file->f_path.dentry, &realpath);
+               realfile = open_with_fake_path(&realpath, flags, realinode,
                                               current_cred());
        }
        revert_creds(old_cred);
@@ -252,6 +255,14 @@ static rwf_t ovl_iocb_to_rwf(int ifl)
        return flags;
 }
 
+static inline void ovl_aio_put(struct ovl_aio_req *aio_req)
+{
+       if (refcount_dec_and_test(&aio_req->ref)) {
+               fdput(aio_req->fd);
+               kmem_cache_free(ovl_aio_request_cachep, aio_req);
+       }
+}
+
 static void ovl_aio_cleanup_handler(struct ovl_aio_req *aio_req)
 {
        struct kiocb *iocb = &aio_req->iocb;
@@ -268,8 +279,7 @@ static void ovl_aio_cleanup_handler(struct ovl_aio_req *aio_req)
        }
 
        orig_iocb->ki_pos = iocb->ki_pos;
-       fdput(aio_req->fd);
-       kmem_cache_free(ovl_aio_request_cachep, aio_req);
+       ovl_aio_put(aio_req);
 }
 
 static void ovl_aio_rw_complete(struct kiocb *iocb, long res, long res2)
@@ -319,7 +329,9 @@ static ssize_t ovl_read_iter(struct kiocb *iocb, struct iov_iter *iter)
                aio_req->orig_iocb = iocb;
                kiocb_clone(&aio_req->iocb, iocb, real.file);
                aio_req->iocb.ki_complete = ovl_aio_rw_complete;
+               refcount_set(&aio_req->ref, 2);
                ret = vfs_iocb_iter_read(real.file, &aio_req->iocb, iter);
+               ovl_aio_put(aio_req);
                if (ret != -EIOCBQUEUED)
                        ovl_aio_cleanup_handler(aio_req);
        }
@@ -390,7 +402,9 @@ static ssize_t ovl_write_iter(struct kiocb *iocb, struct iov_iter *iter)
                kiocb_clone(&aio_req->iocb, iocb, real.file);
                aio_req->iocb.ki_flags = ifl;
                aio_req->iocb.ki_complete = ovl_aio_rw_complete;
+               refcount_set(&aio_req->ref, 2);
                ret = vfs_iocb_iter_write(real.file, &aio_req->iocb, iter);
+               ovl_aio_put(aio_req);
                if (ret != -EIOCBQUEUED)
                        ovl_aio_cleanup_handler(aio_req);
        }
@@ -476,6 +490,39 @@ static int ovl_fsync(struct file *file, loff_t start, loff_t end, int datasync)
        return ret;
 }
 
+#if IS_ENABLED(CONFIG_AUFS_FS)
+/*
+ * In map_files_get_link() (fs/proc/base.c)
+ * we need to determine correct path from overlayfs.
+ * But real_mount(realfile->f_path.mnt) may be not
+ * equal to real_mount(file->f_path.mnt). In such case
+ * fdinfo of the same file which was opened from
+ * /proc/<pid>/map_files/... and "usual" path
+ * will show different mnt_id.
+ *
+ * We solve issue like in aufs by using additional
+ * field on struct vm_area_struct called "vm_prfile"
+ * which is used only for fdinfo/"printing" needs.
+ *
+ * See also mm/prfile.c
+ */
+static void ovl_vm_prfile_set(struct vm_area_struct *vma,
+                             struct file *file)
+{
+       get_file(file);
+       vma->vm_prfile = file;
+#ifndef CONFIG_MMU
+       get_file(file);
+       vma->vm_region->vm_prfile = file;
+#endif
+}
+#else /* !CONFIG_AUFS_FS */
+static void ovl_vm_prfile_set(struct vm_area_struct *vma,
+                             struct file *file)
+{
+}
+#endif/* CONFIG_AUFS_FS */
+
 static int ovl_mmap(struct file *file, struct vm_area_struct *vma)
 {
        struct file *realfile = file->private_data;
@@ -493,6 +540,10 @@ static int ovl_mmap(struct file *file, struct vm_area_struct *vma)
        old_cred = ovl_override_creds(file_inode(file)->i_sb);
        ret = call_mmap(vma->vm_file, vma);
        revert_creds(old_cred);
+
+       if (!ret)
+               ovl_vm_prfile_set(vma, file);
+
        ovl_file_accessed(file);
 
        return ret;