Merge tag 'pci-v5.11-fixes-1' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaa...

[linux-2.6-microblaze.git] / fs / overlayfs / file.c

diff --git a/fs/overlayfs/file.c b/fs/overlayfs/file.c
index efccb7c..bd9dd38 100644 (file)
--- a/fs/overlayfs/file.c
+++ b/fs/overlayfs/file.c
@@ -53,9 +53,10 @@ static struct file *ovl_open_realfile(const struct file *file,
        err = inode_permission(realinode, MAY_OPEN | acc_mode);
        if (err) {
                realfile = ERR_PTR(err);
-       } else if (!inode_owner_or_capable(realinode)) {
-               realfile = ERR_PTR(-EPERM);
        } else {
+               if (!inode_owner_or_capable(realinode))
+                       flags &= ~O_NOATIME;
+
                realfile = open_with_fake_path(&file->f_path, flags, realinode,
                                               current_cred());
        }
@@ -75,12 +76,6 @@ static int ovl_change_flags(struct file *file, unsigned int flags)
        struct inode *inode = file_inode(file);
        int err;
 
-       flags |= OVL_OPEN_FLAGS;
-
-       /* If some flag changed that cannot be changed then something's amiss */
-       if (WARN_ON((file->f_flags ^ flags) & ~OVL_SETFL_MASK))
-               return -EIO;
-
        flags &= OVL_SETFL_MASK;
 
        if (((flags ^ file->f_flags) & O_APPEND) && IS_APPEND(inode))
@@ -397,48 +392,6 @@ out_unlock:
        return ret;
 }
 
-static ssize_t ovl_splice_read(struct file *in, loff_t *ppos,
-                        struct pipe_inode_info *pipe, size_t len,
-                        unsigned int flags)
-{
-       ssize_t ret;
-       struct fd real;
-       const struct cred *old_cred;
-
-       ret = ovl_real_fdget(in, &real);
-       if (ret)
-               return ret;
-
-       old_cred = ovl_override_creds(file_inode(in)->i_sb);
-       ret = generic_file_splice_read(real.file, ppos, pipe, len, flags);
-       revert_creds(old_cred);
-
-       ovl_file_accessed(in);
-       fdput(real);
-       return ret;
-}
-
-static ssize_t
-ovl_splice_write(struct pipe_inode_info *pipe, struct file *out,
-                         loff_t *ppos, size_t len, unsigned int flags)
-{
-       struct fd real;
-       const struct cred *old_cred;
-       ssize_t ret;
-
-       ret = ovl_real_fdget(out, &real);
-       if (ret)
-               return ret;
-
-       old_cred = ovl_override_creds(file_inode(out)->i_sb);
-       ret = iter_file_splice_write(pipe, real.file, ppos, len, flags);
-       revert_creds(old_cred);
-
-       ovl_file_accessed(out);
-       fdput(real);
-       return ret;
-}
-
 static int ovl_fsync(struct file *file, loff_t start, loff_t end, int datasync)
 {
        struct fd real;
@@ -541,46 +494,31 @@ static long ovl_real_ioctl(struct file *file, unsigned int cmd,
                           unsigned long arg)
 {
        struct fd real;
-       const struct cred *old_cred;
        long ret;
 
        ret = ovl_real_fdget(file, &real);
        if (ret)
                return ret;
 
-       old_cred = ovl_override_creds(file_inode(file)->i_sb);
        ret = security_file_ioctl(real.file, cmd, arg);
-       if (!ret)
+       if (!ret) {
+               /*
+                * Don't override creds, since we currently can't safely check
+                * permissions before doing so.
+                */
                ret = vfs_ioctl(real.file, cmd, arg);
-       revert_creds(old_cred);
+       }
 
        fdput(real);
 
        return ret;
 }
 
-static unsigned int ovl_iflags_to_fsflags(unsigned int iflags)
-{
-       unsigned int flags = 0;
-
-       if (iflags & S_SYNC)
-               flags |= FS_SYNC_FL;
-       if (iflags & S_APPEND)
-               flags |= FS_APPEND_FL;
-       if (iflags & S_IMMUTABLE)
-               flags |= FS_IMMUTABLE_FL;
-       if (iflags & S_NOATIME)
-               flags |= FS_NOATIME_FL;
-
-       return flags;
-}
-
 static long ovl_ioctl_set_flags(struct file *file, unsigned int cmd,
-                               unsigned long arg, unsigned int flags)
+                               unsigned long arg)
 {
        long ret;
        struct inode *inode = file_inode(file);
-       unsigned int oldflags;
 
        if (!inode_owner_or_capable(inode))
                return -EACCES;
@@ -591,10 +529,13 @@ static long ovl_ioctl_set_flags(struct file *file, unsigned int cmd,
 
        inode_lock(inode);
 
-       /* Check the capability before cred override */
-       oldflags = ovl_iflags_to_fsflags(READ_ONCE(inode->i_flags));
-       ret = vfs_ioc_setflags_prepare(inode, oldflags, flags);
-       if (ret)
+       /*
+        * Prevent copy up if immutable and has no CAP_LINUX_IMMUTABLE
+        * capability.
+        */
+       ret = -EPERM;
+       if (!ovl_has_upperdata(inode) && IS_IMMUTABLE(inode) &&
+           !capable(CAP_LINUX_IMMUTABLE))
                goto unlock;
 
        ret = ovl_maybe_copy_up(file_dentry(file), O_WRONLY);
@@ -613,46 +554,6 @@ unlock:
 
 }
 
-static long ovl_ioctl_set_fsflags(struct file *file, unsigned int cmd,
-                                 unsigned long arg)
-{
-       unsigned int flags;
-
-       if (get_user(flags, (int __user *) arg))
-               return -EFAULT;
-
-       return ovl_ioctl_set_flags(file, cmd, arg, flags);
-}
-
-static unsigned int ovl_fsxflags_to_fsflags(unsigned int xflags)
-{
-       unsigned int flags = 0;
-
-       if (xflags & FS_XFLAG_SYNC)
-               flags |= FS_SYNC_FL;
-       if (xflags & FS_XFLAG_APPEND)
-               flags |= FS_APPEND_FL;
-       if (xflags & FS_XFLAG_IMMUTABLE)
-               flags |= FS_IMMUTABLE_FL;
-       if (xflags & FS_XFLAG_NOATIME)
-               flags |= FS_NOATIME_FL;
-
-       return flags;
-}
-
-static long ovl_ioctl_set_fsxflags(struct file *file, unsigned int cmd,
-                                  unsigned long arg)
-{
-       struct fsxattr fa;
-
-       memset(&fa, 0, sizeof(fa));
-       if (copy_from_user(&fa, (void __user *) arg, sizeof(fa)))
-               return -EFAULT;
-
-       return ovl_ioctl_set_flags(file, cmd, arg,
-                                  ovl_fsxflags_to_fsflags(fa.fsx_xflags));
-}
-
 long ovl_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
 {
        long ret;
@@ -663,12 +564,9 @@ long ovl_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
                ret = ovl_real_ioctl(file, cmd, arg);
                break;
 
-       case FS_IOC_SETFLAGS:
-               ret = ovl_ioctl_set_fsflags(file, cmd, arg);
-               break;
-
        case FS_IOC_FSSETXATTR:
-               ret = ovl_ioctl_set_fsxflags(file, cmd, arg);
+       case FS_IOC_SETFLAGS:
+               ret = ovl_ioctl_set_flags(file, cmd, arg);
                break;
 
        default:
@@ -801,8 +699,8 @@ const struct file_operations ovl_file_operations = {
 #ifdef CONFIG_COMPAT
        .compat_ioctl   = ovl_compat_ioctl,
 #endif
-       .splice_read    = ovl_splice_read,
-       .splice_write   = ovl_splice_write,
+       .splice_read    = generic_file_splice_read,
+       .splice_write   = iter_file_splice_write,
 
        .copy_file_range        = ovl_copy_file_range,
        .remap_file_range       = ovl_remap_file_range,