autofs: add autofs_parse_fd()

Factor out the fd mount option handling.

Signed-off-by: Ian Kent <raven@themaw.net>
Reviewed-by: Bill O'Donnell <bodonnel@redhat.com>
Message-Id: <20230922041215.13675-3-raven@themaw.net>
Signed-off-by: Christian Brauner <brauner@kernel.org>

diff --git a/fs/autofs/inode.c b/fs/autofs/inode.c
index 2b49662ed237def8f00bfcd888cfdc73c2511b92..e279e275b0a5487fb20aaf9d295838056d2403e8 100644 (file)
--- a/fs/autofs/inode.c
+++ b/fs/autofs/inode.c
@@ -129,6 +129,33 @@ static const match_table_t tokens = {
        {Opt_err, NULL}
 };
 
+static int autofs_parse_fd(struct autofs_sb_info *sbi, int fd)
+{
+       struct file *pipe;
+       int ret;
+
+       pipe = fget(fd);
+       if (!pipe) {
+               pr_err("could not open pipe file descriptor\n");
+               return -EBADF;
+       }
+
+       ret = autofs_check_pipe(pipe);
+       if (ret < 0) {
+               pr_err("Invalid/unusable pipe\n");
+               fput(pipe);
+               return -EBADF;
+       }
+
+       if (sbi->pipe)
+               fput(sbi->pipe);
+
+       sbi->pipefd = fd;
+       sbi->pipe = pipe;
+
+       return 0;
+}
+
 static int parse_options(char *options,
                         struct inode *root, int *pgrp, bool *pgrp_set,
                         struct autofs_sb_info *sbi)
@@ -139,6 +166,7 @@ static int parse_options(char *options,
        int pipefd = -1;
        kuid_t uid;
        kgid_t gid;
+       int ret;
 
        root->i_uid = current_uid();
        root->i_gid = current_gid();
@@ -162,7 +190,9 @@ static int parse_options(char *options,
                case Opt_fd:
                        if (match_int(args, &pipefd))
                                return 1;
-                       sbi->pipefd = pipefd;
+                       ret = autofs_parse_fd(sbi, pipefd);
+                       if (ret)
+                               return 1;
                        break;
                case Opt_uid:
                        if (match_int(args, &option))
@@ -222,7 +252,6 @@ int autofs_fill_super(struct super_block *s, void *data, int silent)
 {
        struct inode *root_inode;
        struct dentry *root;
-       struct file *pipe;
        struct autofs_sb_info *sbi;
        struct autofs_info *ino;
        int pgrp = 0;
@@ -275,7 +304,6 @@ int autofs_fill_super(struct super_block *s, void *data, int silent)
                ret = -ENOMEM;
                goto fail_ino;
        }
-       pipe = NULL;
 
        root->d_fsdata = ino;
 
@@ -321,16 +349,7 @@ int autofs_fill_super(struct super_block *s, void *data, int silent)
 
        pr_debug("pipe fd = %d, pgrp = %u\n",
                 sbi->pipefd, pid_nr(sbi->oz_pgrp));
-       pipe = fget(sbi->pipefd);
 
-       if (!pipe) {
-               pr_err("could not open pipe file descriptor\n");
-               goto fail_put_pid;
-       }
-       ret = autofs_prepare_pipe(pipe);
-       if (ret < 0)
-               goto fail_fput;
-       sbi->pipe = pipe;
        sbi->flags &= ~AUTOFS_SBI_CATATONIC;
 
        /*
@@ -342,11 +361,6 @@ int autofs_fill_super(struct super_block *s, void *data, int silent)
        /*
         * Failure ... clean up.
         */
-fail_fput:
-       pr_err("pipe file descriptor does not contain proper ops\n");
-       fput(pipe);
-fail_put_pid:
-       put_pid(sbi->oz_pgrp);
 fail_dput:
        dput(root);
        goto fail_free;