1 files changed, 35 insertions, 42 deletions

diff --git a/fs/autofs4/dev-ioctl.c b/fs/autofs4/dev-ioctl.c
index c7fcc7438843..fc09eb77ddf3 100644
--- a/fs/autofs4/dev-ioctl.c
+++ b/fs/autofs4/dev-ioctl.c
@@ -75,7 +75,7 @@ static int check_dev_ioctl_version(int cmd, struct autofs_dev_ioctl *param)
 	if ((param->ver_major != AUTOFS_DEV_IOCTL_VERSION_MAJOR) ||
 	    (param->ver_minor > AUTOFS_DEV_IOCTL_VERSION_MINOR)) {
 		pr_warn("ioctl control interface version mismatch: "
-			"kernel(%u.%u), user(%u.%u), cmd(%d)\n",
+			"kernel(%u.%u), user(%u.%u), cmd(0x%08x)\n",
 			AUTOFS_DEV_IOCTL_VERSION_MAJOR,
 			AUTOFS_DEV_IOCTL_VERSION_MINOR,
 			param->ver_major, param->ver_minor, cmd);
@@ -172,6 +172,17 @@ static struct autofs_sb_info *autofs_dev_ioctl_sbi(struct file *f)
 	return sbi;
 }
 
+/* Return autofs dev ioctl version */
+static int autofs_dev_ioctl_version(struct file *fp,
+				    struct autofs_sb_info *sbi,
+				    struct autofs_dev_ioctl *param)
+{
+	/* This should have already been set. */
+	param->ver_major = AUTOFS_DEV_IOCTL_VERSION_MAJOR;
+	param->ver_minor = AUTOFS_DEV_IOCTL_VERSION_MINOR;
+	return 0;
+}
+
 /* Return autofs module protocol version */
 static int autofs_dev_ioctl_protover(struct file *fp,
 				     struct autofs_sb_info *sbi,
@@ -586,41 +597,25 @@ out:
 
 static ioctl_fn lookup_dev_ioctl(unsigned int cmd)
 {
-	static struct {
-		int cmd;
-		ioctl_fn fn;
-	} _ioctls[] = {
-		{cmd_idx(AUTOFS_DEV_IOCTL_VERSION_CMD), NULL},
-		{cmd_idx(AUTOFS_DEV_IOCTL_PROTOVER_CMD),
-			 autofs_dev_ioctl_protover},
-		{cmd_idx(AUTOFS_DEV_IOCTL_PROTOSUBVER_CMD),
-			 autofs_dev_ioctl_protosubver},
-		{cmd_idx(AUTOFS_DEV_IOCTL_OPENMOUNT_CMD),
-			 autofs_dev_ioctl_openmount},
-		{cmd_idx(AUTOFS_DEV_IOCTL_CLOSEMOUNT_CMD),
-			 autofs_dev_ioctl_closemount},
-		{cmd_idx(AUTOFS_DEV_IOCTL_READY_CMD),
-			 autofs_dev_ioctl_ready},
-		{cmd_idx(AUTOFS_DEV_IOCTL_FAIL_CMD),
-			 autofs_dev_ioctl_fail},
-		{cmd_idx(AUTOFS_DEV_IOCTL_SETPIPEFD_CMD),
-			 autofs_dev_ioctl_setpipefd},
-		{cmd_idx(AUTOFS_DEV_IOCTL_CATATONIC_CMD),
-			 autofs_dev_ioctl_catatonic},
-		{cmd_idx(AUTOFS_DEV_IOCTL_TIMEOUT_CMD),
-			 autofs_dev_ioctl_timeout},
-		{cmd_idx(AUTOFS_DEV_IOCTL_REQUESTER_CMD),
-			 autofs_dev_ioctl_requester},
-		{cmd_idx(AUTOFS_DEV_IOCTL_EXPIRE_CMD),
-			 autofs_dev_ioctl_expire},
-		{cmd_idx(AUTOFS_DEV_IOCTL_ASKUMOUNT_CMD),
-			 autofs_dev_ioctl_askumount},
-		{cmd_idx(AUTOFS_DEV_IOCTL_ISMOUNTPOINT_CMD),
-			 autofs_dev_ioctl_ismountpoint}
+	static ioctl_fn _ioctls[] = {
+		autofs_dev_ioctl_version,
+		autofs_dev_ioctl_protover,
+		autofs_dev_ioctl_protosubver,
+		autofs_dev_ioctl_openmount,
+		autofs_dev_ioctl_closemount,
+		autofs_dev_ioctl_ready,
+		autofs_dev_ioctl_fail,
+		autofs_dev_ioctl_setpipefd,
+		autofs_dev_ioctl_catatonic,
+		autofs_dev_ioctl_timeout,
+		autofs_dev_ioctl_requester,
+		autofs_dev_ioctl_expire,
+		autofs_dev_ioctl_askumount,
+		autofs_dev_ioctl_ismountpoint,
 	};
 	unsigned int idx = cmd_idx(cmd);
 
-	return (idx >= ARRAY_SIZE(_ioctls)) ? NULL : _ioctls[idx].fn;
+	return (idx >= ARRAY_SIZE(_ioctls)) ? NULL : _ioctls[idx];
 }
 
 /* ioctl dispatcher */
@@ -642,7 +637,7 @@ static int _autofs_dev_ioctl(unsigned int command,
 	cmd = _IOC_NR(command);
 
 	if (_IOC_TYPE(command) != _IOC_TYPE(AUTOFS_DEV_IOCTL_IOC_FIRST) ||
-	    cmd - cmd_first >= AUTOFS_DEV_IOCTL_IOC_COUNT) {
+	    cmd - cmd_first > AUTOFS_DEV_IOCTL_IOC_COUNT) {
 		return -ENOTTY;
 	}
 
@@ -655,14 +650,11 @@ static int _autofs_dev_ioctl(unsigned int command,
 	if (err)
 		goto out;
 
-	/* The validate routine above always sets the version */
-	if (cmd == AUTOFS_DEV_IOCTL_VERSION_CMD)
-		goto done;
-
 	fn = lookup_dev_ioctl(cmd);
 	if (!fn) {
 		pr_warn("unknown command 0x%08x\n", command);
-		return -ENOTTY;
+		err = -ENOTTY;
+		goto out;
 	}
 
 	fp = NULL;
@@ -671,9 +663,11 @@ static int _autofs_dev_ioctl(unsigned int command,
 	/*
 	 * For obvious reasons the openmount can't have a file
 	 * descriptor yet. We don't take a reference to the
-	 * file during close to allow for immediate release.
+	 * file during close to allow for immediate release,
+	 * and the same for retrieving ioctl version.
 	 */
-	if (cmd != AUTOFS_DEV_IOCTL_OPENMOUNT_CMD &&
+	if (cmd != AUTOFS_DEV_IOCTL_VERSION_CMD &&
+	    cmd != AUTOFS_DEV_IOCTL_OPENMOUNT_CMD &&
 	    cmd != AUTOFS_DEV_IOCTL_CLOSEMOUNT_CMD) {
 		fp = fget(param->ioctlfd);
 		if (!fp) {
@@ -706,7 +700,6 @@ cont:
 
 	if (fp)
 		fput(fp);
-done:
 	if (err >= 0 && copy_to_user(user, param, AUTOFS_DEV_IOCTL_SIZE))
 		err = -EFAULT;
 out: