diff options
| -rw-r--r-- | fs/namei.c | 6 | ||||
| -rw-r--r-- | fs/stat.c | 4 | ||||
| -rw-r--r-- | include/linux/fcntl.h | 1 | ||||
| -rw-r--r-- | include/linux/namei.h | 2 |
4 files changed, 12 insertions, 1 deletions
diff --git a/fs/namei.c b/fs/namei.c index 9d3033dc22e9..dc50bfb2f5d6 100644 --- a/fs/namei.c +++ b/fs/namei.c @@ -908,6 +908,12 @@ static int follow_automount(struct path *path, unsigned flags, if (!path->dentry->d_op || !path->dentry->d_op->d_automount) return -EREMOTE; + /* We don't want to mount if someone supplied AT_NO_AUTOMOUNT + * and this is the terminal part of the path. + */ + if ((flags & LOOKUP_NO_AUTOMOUNT) && !(flags & LOOKUP_CONTINUE)) + return -EISDIR; /* we actually want to stop here */ + /* We want to mount if someone is trying to open/create a file of any * type under the mountpoint, wants to traverse through the mountpoint * or wants to open the mounted directory. diff --git a/fs/stat.c b/fs/stat.c index 12e90e213900..d5c61cf2b703 100644 --- a/fs/stat.c +++ b/fs/stat.c @@ -75,11 +75,13 @@ int vfs_fstatat(int dfd, const char __user *filename, struct kstat *stat, int error = -EINVAL; int lookup_flags = 0; - if ((flag & ~AT_SYMLINK_NOFOLLOW) != 0) + if ((flag & ~(AT_SYMLINK_NOFOLLOW | AT_NO_AUTOMOUNT)) != 0) goto out; if (!(flag & AT_SYMLINK_NOFOLLOW)) lookup_flags |= LOOKUP_FOLLOW; + if (flag & AT_NO_AUTOMOUNT) + lookup_flags |= LOOKUP_NO_AUTOMOUNT; error = user_path_at(dfd, filename, lookup_flags, &path); if (error) diff --git a/include/linux/fcntl.h b/include/linux/fcntl.h index afc00af3229b..a562fa5fb4e3 100644 --- a/include/linux/fcntl.h +++ b/include/linux/fcntl.h @@ -45,6 +45,7 @@ #define AT_REMOVEDIR 0x200 /* Remove directory instead of unlinking file. */ #define AT_SYMLINK_FOLLOW 0x400 /* Follow symbolic links. */ +#define AT_NO_AUTOMOUNT 0x800 /* Suppress terminal automount traversal */ #ifdef __KERNEL__ diff --git a/include/linux/namei.h b/include/linux/namei.h index 8ef2c789c2a8..f276d4fa01fc 100644 --- a/include/linux/namei.h +++ b/include/linux/namei.h @@ -45,6 +45,7 @@ enum {LAST_NORM, LAST_ROOT, LAST_DOT, LAST_DOTDOT, LAST_BIND}; * - ending slashes ok even for nonexistent files * - internal "there are more path components" flag * - dentry cache is untrusted; force a real lookup + * - suppress terminal automount */ #define LOOKUP_FOLLOW 0x0001 #define LOOKUP_DIRECTORY 0x0002 @@ -53,6 +54,7 @@ enum {LAST_NORM, LAST_ROOT, LAST_DOT, LAST_DOTDOT, LAST_BIND}; #define LOOKUP_PARENT 0x0010 #define LOOKUP_REVAL 0x0020 #define LOOKUP_RCU 0x0040 +#define LOOKUP_NO_AUTOMOUNT 0x0080 /* * Intent data */ |