diff --git a/fs/cifs/cifs_fs_sb.h b/fs/cifs/cifs_fs_sb.h index 2a5325a7ae49..9c45b3a82ad9 100644 --- a/fs/cifs/cifs_fs_sb.h +++ b/fs/cifs/cifs_fs_sb.h @@ -55,6 +55,7 @@ #define CIFS_MOUNT_MODE_FROM_SID 0x10000000 /* retrieve mode from special ACE */ #define CIFS_MOUNT_RO_CACHE 0x20000000 /* assumes share will not change */ #define CIFS_MOUNT_RW_CACHE 0x40000000 /* assumes only client accessing */ +#define CIFS_MOUNT_SHUTDOWN 0x80000000 struct cifs_sb_info { struct rb_root tlink_tree; diff --git a/fs/cifs/cifs_ioctl.h b/fs/cifs/cifs_ioctl.h index 153d5c842a9b..f262c64516bc 100644 --- a/fs/cifs/cifs_ioctl.h +++ b/fs/cifs/cifs_ioctl.h @@ -78,3 +78,19 @@ struct smb3_notify { #define CIFS_QUERY_INFO _IOWR(CIFS_IOCTL_MAGIC, 7, struct smb_query_info) #define CIFS_DUMP_KEY _IOWR(CIFS_IOCTL_MAGIC, 8, struct smb3_key_debug_info) #define CIFS_IOC_NOTIFY _IOW(CIFS_IOCTL_MAGIC, 9, struct smb3_notify) +#define CIFS_IOC_SHUTDOWN _IOR ('X', 125, __u32) + +/* + * Flags for going down operation + */ +#define CIFS_GOING_FLAGS_DEFAULT 0x0 /* going down */ +#define CIFS_GOING_FLAGS_LOGFLUSH 0x1 /* flush log but not data */ +#define CIFS_GOING_FLAGS_NOLOGFLUSH 0x2 /* don't flush log nor data */ + +static inline bool cifs_forced_shutdown(struct cifs_sb_info *sbi) +{ + if (CIFS_MOUNT_SHUTDOWN & sbi->mnt_cifs_flags) + return true; + else + return false; +} diff --git a/fs/cifs/dir.c b/fs/cifs/dir.c index 03afad8b24af..263720131986 100644 --- a/fs/cifs/dir.c +++ b/fs/cifs/dir.c @@ -34,6 +34,7 @@ #include "cifs_fs_sb.h" #include "cifs_unicode.h" #include "fs_context.h" +#include "cifs_ioctl.h" static void renew_parental_timestamps(struct dentry *direntry) @@ -429,6 +430,9 @@ cifs_atomic_open(struct inode *inode, struct dentry *direntry, __u32 oplock; struct cifsFileInfo *file_info; + if (unlikely(cifs_forced_shutdown(CIFS_SB(inode->i_sb)))) + return -EIO; + /* * Posix open is only called (at lookup time) for file create now. For * opens (rather than creates), because we do not know if it is a file @@ -545,6 +549,9 @@ int cifs_create(struct user_namespace *mnt_userns, struct inode *inode, cifs_dbg(FYI, "cifs_create parent inode = 0x%p name is: %pd and dentry = 0x%p\n", inode, direntry, direntry); + if (unlikely(cifs_forced_shutdown(CIFS_SB(inode->i_sb)))) + return -EIO; + tlink = cifs_sb_tlink(CIFS_SB(inode->i_sb)); rc = PTR_ERR(tlink); if (IS_ERR(tlink)) @@ -582,6 +589,9 @@ int cifs_mknod(struct user_namespace *mnt_userns, struct inode *inode, return -EINVAL; cifs_sb = CIFS_SB(inode->i_sb); + if (unlikely(cifs_forced_shutdown(cifs_sb))) + return -EIO; + tlink = cifs_sb_tlink(cifs_sb); if (IS_ERR(tlink)) return PTR_ERR(tlink); diff --git a/fs/cifs/file.c b/fs/cifs/file.c index 7e97aeabd616..c95893351b6c 100644 --- a/fs/cifs/file.c +++ b/fs/cifs/file.c @@ -45,6 +45,7 @@ #include "fscache.h" #include "smbdirect.h" #include "fs_context.h" +#include "cifs_ioctl.h" static inline int cifs_convert_flags(unsigned int flags) { @@ -542,6 +543,11 @@ int cifs_open(struct inode *inode, struct file *file) xid = get_xid(); cifs_sb = CIFS_SB(inode->i_sb); + if (unlikely(cifs_forced_shutdown(cifs_sb))) { + free_xid(xid); + return -EIO; + } + tlink = cifs_sb_tlink(cifs_sb); if (IS_ERR(tlink)) { free_xid(xid); diff --git a/fs/cifs/fs_context.c b/fs/cifs/fs_context.c index 3e0d016849e3..1d6e0e15b034 100644 --- a/fs/cifs/fs_context.c +++ b/fs/cifs/fs_context.c @@ -1642,6 +1642,7 @@ void smb3_update_mnt_flags(struct cifs_sb_info *cifs_sb) cifs_dbg(VFS, "mount options mfsymlinks and sfu both enabled\n"); } } + cifs_sb->mnt_cifs_flags &= ~CIFS_MOUNT_SHUTDOWN; return; } diff --git a/fs/cifs/inode.c b/fs/cifs/inode.c index b4326ffcefce..728ff45b6667 100644 --- a/fs/cifs/inode.c +++ b/fs/cifs/inode.c @@ -26,7 +26,6 @@ #include #include #include - #include #include "cifsfs.h" #include "cifspdu.h" @@ -38,7 +37,7 @@ #include "cifs_unicode.h" #include "fscache.h" #include "fs_context.h" - +#include "cifs_ioctl.h" static void cifs_set_ops(struct inode *inode) { @@ -1623,6 +1622,9 @@ int cifs_unlink(struct inode *dir, struct dentry *dentry) cifs_dbg(FYI, "cifs_unlink, dir=0x%p, dentry=0x%p\n", dir, dentry); + if (unlikely(cifs_forced_shutdown(cifs_sb))) + return -EIO; + tlink = cifs_sb_tlink(cifs_sb); if (IS_ERR(tlink)) return PTR_ERR(tlink); @@ -1876,6 +1878,8 @@ int cifs_mkdir(struct user_namespace *mnt_userns, struct inode *inode, mode, inode); cifs_sb = CIFS_SB(inode->i_sb); + if (unlikely(cifs_forced_shutdown(cifs_sb))) + return -EIO; tlink = cifs_sb_tlink(cifs_sb); if (IS_ERR(tlink)) return PTR_ERR(tlink); @@ -1958,6 +1962,11 @@ int cifs_rmdir(struct inode *inode, struct dentry *direntry) } cifs_sb = CIFS_SB(inode->i_sb); + if (unlikely(cifs_forced_shutdown(cifs_sb))) { + rc = -EIO; + goto rmdir_exit; + } + tlink = cifs_sb_tlink(cifs_sb); if (IS_ERR(tlink)) { rc = PTR_ERR(tlink); @@ -2092,6 +2101,9 @@ cifs_rename2(struct user_namespace *mnt_userns, struct inode *source_dir, return -EINVAL; cifs_sb = CIFS_SB(source_dir->i_sb); + if (unlikely(cifs_forced_shutdown(cifs_sb))) + return -EIO; + tlink = cifs_sb_tlink(cifs_sb); if (IS_ERR(tlink)) return PTR_ERR(tlink); @@ -2408,6 +2420,9 @@ int cifs_getattr(struct user_namespace *mnt_userns, const struct path *path, struct inode *inode = d_inode(dentry); int rc; + if (unlikely(cifs_forced_shutdown(CIFS_SB(inode->i_sb)))) + return -EIO; + /* * We need to be sure that all dirty pages are written and the server * has actual ctime, mtime and file length. @@ -2480,6 +2495,9 @@ int cifs_fiemap(struct inode *inode, struct fiemap_extent_info *fei, u64 start, struct cifsFileInfo *cfile; int rc; + if (unlikely(cifs_forced_shutdown(cifs_sb))) + return -EIO; + /* * We need to be sure that all dirty pages are written as they * might fill holes on the server. @@ -2966,6 +2984,9 @@ cifs_setattr(struct user_namespace *mnt_userns, struct dentry *direntry, struct cifs_tcon *pTcon = cifs_sb_master_tcon(cifs_sb); int rc, retries = 0; + if (unlikely(cifs_forced_shutdown(cifs_sb))) + return -EIO; + do { if (pTcon->unix_ext) rc = cifs_setattr_unix(direntry, attrs); diff --git a/fs/cifs/ioctl.c b/fs/cifs/ioctl.c index 08d99fec593e..ef41fa878793 100644 --- a/fs/cifs/ioctl.c +++ b/fs/cifs/ioctl.c @@ -164,6 +164,56 @@ static long smb_mnt_get_fsinfo(unsigned int xid, struct cifs_tcon *tcon, return rc; } +static int cifs_shutdown(struct super_block *sb, unsigned long arg) +{ + struct cifs_sb_info *sbi = CIFS_SB(sb); + __u32 flags; + + if (!capable(CAP_SYS_ADMIN)) + return -EPERM; + + if (get_user(flags, (__u32 __user *)arg)) + return -EFAULT; + + if (flags > CIFS_GOING_FLAGS_NOLOGFLUSH) + return -EINVAL; + + if (cifs_forced_shutdown(sbi)) + return 0; + + cifs_dbg(VFS, "shut down requested (%d)", flags); +/* trace_cifs_shutdown(sb, flags);*/ + + /* + * see: + * https://man7.org/linux/man-pages/man2/ioctl_xfs_goingdown.2.html + * for more information and description of original intent of the flags + */ + switch (flags) { + /* + * We could add support later for default flag which requires: + * "Flush all dirty data and metadata to disk" + * would need to call syncfs or equivalent to flush page cache for + * the mount and then issue fsync to server (if nostrictsync not set) + */ + case CIFS_GOING_FLAGS_DEFAULT: + cifs_dbg(FYI, "shutdown with default flag not supported\n"); + return -EINVAL; + /* + * FLAGS_LOGFLUSH is easy since it asks to write out metadata (not + * data) but metadata writes are not cached on the client, so can treat + * it similarly to NOLOGFLUSH + */ + case CIFS_GOING_FLAGS_LOGFLUSH: + case CIFS_GOING_FLAGS_NOLOGFLUSH: + sbi->mnt_cifs_flags |= CIFS_MOUNT_SHUTDOWN; + return 0; + default: + return -EINVAL; + } + return 0; +} + long cifs_ioctl(struct file *filep, unsigned int command, unsigned long arg) { struct inode *inode = file_inode(filep); @@ -325,6 +375,9 @@ long cifs_ioctl(struct file *filep, unsigned int command, unsigned long arg) rc = -EOPNOTSUPP; cifs_put_tlink(tlink); break; + case CIFS_IOC_SHUTDOWN: + rc = cifs_shutdown(inode->i_sb, arg); + break; default: cifs_dbg(FYI, "unsupported ioctl\n"); break; diff --git a/fs/cifs/link.c b/fs/cifs/link.c index 616e1bc0cc0a..1cbe7ec73728 100644 --- a/fs/cifs/link.c +++ b/fs/cifs/link.c @@ -30,6 +30,7 @@ #include "cifs_fs_sb.h" #include "cifs_unicode.h" #include "smb2proto.h" +#include "cifs_ioctl.h" /* * M-F Symlink Functions - Begin @@ -518,6 +519,9 @@ cifs_hardlink(struct dentry *old_file, struct inode *inode, struct TCP_Server_Info *server; struct cifsInodeInfo *cifsInode; + if (unlikely(cifs_forced_shutdown(cifs_sb))) + return -EIO; + tlink = cifs_sb_tlink(cifs_sb); if (IS_ERR(tlink)) return PTR_ERR(tlink); @@ -682,6 +686,9 @@ cifs_symlink(struct user_namespace *mnt_userns, struct inode *inode, void *page = alloc_dentry_path(); struct inode *newinode = NULL; + if (unlikely(cifs_forced_shutdown(cifs_sb))) + return -EIO; + xid = get_xid(); tlink = cifs_sb_tlink(cifs_sb); diff --git a/fs/cifs/xattr.c b/fs/cifs/xattr.c index e351b945135b..aa3e8ca0457c 100644 --- a/fs/cifs/xattr.c +++ b/fs/cifs/xattr.c @@ -30,6 +30,7 @@ #include "cifs_debug.h" #include "cifs_fs_sb.h" #include "cifs_unicode.h" +#include "cifs_ioctl.h" #define MAX_EA_VALUE_SIZE CIFSMaxBufSize #define CIFS_XATTR_CIFS_ACL "system.cifs_acl" /* DACL only */ @@ -421,6 +422,9 @@ ssize_t cifs_listxattr(struct dentry *direntry, char *data, size_t buf_size) const char *full_path; void *page; + if (unlikely(cifs_forced_shutdown(cifs_sb))) + return -EIO; + if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NO_XATTR) return -EOPNOTSUPP;