From a5f85d7834f7e1456e799c79a2a83fc11b90cfe2 Mon Sep 17 00:00:00 2001 From: Al Viro Date: Tue, 1 Mar 2022 00:05:29 -0500 Subject: uninline may_mount() and don't opencode it in fspick(2)/fsopen(2) It's done once per (mount-related) syscall and there's no point whatsoever making it inline. Signed-off-by: Al Viro --- fs/fsopen.c | 4 ++-- fs/internal.h | 1 + fs/namespace.c | 2 +- 3 files changed, 4 insertions(+), 3 deletions(-) diff --git a/fs/fsopen.c b/fs/fsopen.c index 27a890aa493a..fc9d2d9fd234 100644 --- a/fs/fsopen.c +++ b/fs/fsopen.c @@ -119,7 +119,7 @@ SYSCALL_DEFINE2(fsopen, const char __user *, _fs_name, unsigned int, flags) const char *fs_name; int ret; - if (!ns_capable(current->nsproxy->mnt_ns->user_ns, CAP_SYS_ADMIN)) + if (!may_mount()) return -EPERM; if (flags & ~FSOPEN_CLOEXEC) @@ -162,7 +162,7 @@ SYSCALL_DEFINE3(fspick, int, dfd, const char __user *, path, unsigned int, flags unsigned int lookup_flags; int ret; - if (!ns_capable(current->nsproxy->mnt_ns->user_ns, CAP_SYS_ADMIN)) + if (!may_mount()) return -EPERM; if ((flags & ~(FSPICK_CLOEXEC | diff --git a/fs/internal.h b/fs/internal.h index 08503dc68d2b..09ed7fe12b73 100644 --- a/fs/internal.h +++ b/fs/internal.h @@ -84,6 +84,7 @@ extern int __mnt_want_write_file(struct file *); extern void __mnt_drop_write_file(struct file *); extern void dissolve_on_fput(struct vfsmount *); +extern bool may_mount(void); int path_mount(const char *dev_name, struct path *path, const char *type_page, unsigned long flags, void *data_page); diff --git a/fs/namespace.c b/fs/namespace.c index a0a36bfa3aa0..c3a80ffaf1e5 100644 --- a/fs/namespace.c +++ b/fs/namespace.c @@ -1760,7 +1760,7 @@ out_unlock: /* * Is the caller allowed to modify his namespace? */ -static inline bool may_mount(void) +bool may_mount(void) { return ns_capable(current->nsproxy->mnt_ns->user_ns, CAP_SYS_ADMIN); } -- cgit v1.2.3 From 59df85d5fbae17175c391d89ad03e9e7a01b7a55 Mon Sep 17 00:00:00 2001 From: Al Viro Date: Tue, 1 Mar 2022 19:56:53 -0500 Subject: linux/mount.h: trim includes Signed-off-by: Al Viro --- include/linux/mount.h | 17 +++++------------ 1 file changed, 5 insertions(+), 12 deletions(-) diff --git a/include/linux/mount.h b/include/linux/mount.h index 7f18a7555dff..b3b149dcbf96 100644 --- a/include/linux/mount.h +++ b/include/linux/mount.h @@ -11,17 +11,15 @@ #define _LINUX_MOUNT_H #include -#include -#include -#include -#include -#include +#include struct super_block; -struct vfsmount; struct dentry; -struct mnt_namespace; +struct user_namespace; +struct file_system_type; struct fs_context; +struct file; +struct path; #define MNT_NOSUID 0x01 #define MNT_NODEV 0x02 @@ -81,9 +79,6 @@ static inline struct user_namespace *mnt_user_ns(const struct vfsmount *mnt) return smp_load_acquire(&mnt->mnt_userns); } -struct file; /* forward dec */ -struct path; - extern int mnt_want_write(struct vfsmount *mnt); extern int mnt_want_write_file(struct file *file); extern void mnt_drop_write(struct vfsmount *mnt); @@ -94,12 +89,10 @@ extern struct vfsmount *mnt_clone_internal(const struct path *path); extern bool __mnt_is_readonly(struct vfsmount *mnt); extern bool mnt_may_suid(struct vfsmount *mnt); -struct path; extern struct vfsmount *clone_private_mount(const struct path *path); extern int __mnt_want_write(struct vfsmount *); extern void __mnt_drop_write(struct vfsmount *); -struct file_system_type; extern struct vfsmount *fc_mount(struct fs_context *fc); extern struct vfsmount *vfs_create_mount(struct fs_context *fc); extern struct vfsmount *vfs_kern_mount(struct file_system_type *type, -- cgit v1.2.3 From f6957b7191ed8b55c1d2a28fa23c6a7d327b4408 Mon Sep 17 00:00:00 2001 From: Al Viro Date: Tue, 1 Mar 2022 20:35:41 -0500 Subject: m->mnt_root->d_inode->i_sb is a weird way to spell m->mnt_sb... Signed-off-by: Al Viro --- fs/nfs/nfs4file.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/fs/nfs/nfs4file.c b/fs/nfs/nfs4file.c index d258933cf8c8..e6d44fae26ba 100644 --- a/fs/nfs/nfs4file.c +++ b/fs/nfs/nfs4file.c @@ -326,7 +326,7 @@ static struct file *__nfs42_ssc_open(struct vfsmount *ss_mnt, char *read_name = NULL; int len, status = 0; - server = NFS_SERVER(ss_mnt->mnt_root->d_inode); + server = NFS_SB(ss_mnt->mnt_sb); if (!fattr) return ERR_PTR(-ENOMEM); @@ -344,7 +344,7 @@ static struct file *__nfs42_ssc_open(struct vfsmount *ss_mnt, goto out; snprintf(read_name, len, SSC_READ_NAME_BODY, read_name_gen++); - r_ino = nfs_fhget(ss_mnt->mnt_root->d_inode->i_sb, src_fh, fattr); + r_ino = nfs_fhget(ss_mnt->mnt_sb, src_fh, fattr); if (IS_ERR(r_ino)) { res = ERR_CAST(r_ino); goto out_free_name; -- cgit v1.2.3 From 279b192c23d2fc9cb9e8c3851d6cad968f51789f Mon Sep 17 00:00:00 2001 From: Al Viro Date: Wed, 2 Mar 2022 16:11:23 -0500 Subject: blob_to_mnt(): kern_unmount() is needed to undo kern_mount() plain mntput() won't do. Signed-off-by: Al Viro --- kernel/usermode_driver.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/kernel/usermode_driver.c b/kernel/usermode_driver.c index 9dae1f648713..8303f4c7ca71 100644 --- a/kernel/usermode_driver.c +++ b/kernel/usermode_driver.c @@ -28,7 +28,7 @@ static struct vfsmount *blob_to_mnt(const void *data, size_t len, const char *na file = file_open_root_mnt(mnt, name, O_CREAT | O_WRONLY, 0700); if (IS_ERR(file)) { - mntput(mnt); + kern_unmount(mnt); return ERR_CAST(file); } @@ -38,7 +38,7 @@ static struct vfsmount *blob_to_mnt(const void *data, size_t len, const char *na if (err >= 0) err = -ENOMEM; filp_close(file, NULL); - mntput(mnt); + kern_unmount(mnt); return ERR_PTR(err); } -- cgit v1.2.3 From 70f8d9c5750bbb0ca4ef7e23d6abcb05e6061138 Mon Sep 17 00:00:00 2001 From: Al Viro Date: Wed, 2 Mar 2022 17:49:09 -0500 Subject: move mount-related externs from fs.h to mount.h Signed-off-by: Al Viro --- arch/alpha/kernel/osf_sys.c | 1 + include/linux/fs.h | 11 ----------- include/linux/mount.h | 12 ++++++++++++ security/smack/smackfs.c | 1 + 4 files changed, 14 insertions(+), 11 deletions(-) diff --git a/arch/alpha/kernel/osf_sys.c b/arch/alpha/kernel/osf_sys.c index 8bbeebb73cf0..d257293401e2 100644 --- a/arch/alpha/kernel/osf_sys.c +++ b/arch/alpha/kernel/osf_sys.c @@ -36,6 +36,7 @@ #include #include #include +#include #include #include #include diff --git a/include/linux/fs.h b/include/linux/fs.h index bbde95387a23..14df7c049b43 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -2461,22 +2461,11 @@ struct super_block *sget(struct file_system_type *type, extern int register_filesystem(struct file_system_type *); extern int unregister_filesystem(struct file_system_type *); -extern struct vfsmount *kern_mount(struct file_system_type *); -extern void kern_unmount(struct vfsmount *mnt); -extern int may_umount_tree(struct vfsmount *); -extern int may_umount(struct vfsmount *); -extern long do_mount(const char *, const char __user *, - const char *, unsigned long, void *); -extern struct vfsmount *collect_mounts(const struct path *); -extern void drop_collected_mounts(struct vfsmount *); -extern int iterate_mounts(int (*)(struct vfsmount *, void *), void *, - struct vfsmount *); extern int vfs_statfs(const struct path *, struct kstatfs *); extern int user_statfs(const char __user *, struct kstatfs *); extern int fd_statfs(int, struct kstatfs *); extern int freeze_super(struct super_block *super); extern int thaw_super(struct super_block *super); -extern bool our_mnt(struct vfsmount *mnt); extern __printf(2, 3) int super_setup_bdi_name(struct super_block *sb, char *fmt, ...); extern int super_setup_bdi(struct super_block *sb); diff --git a/include/linux/mount.h b/include/linux/mount.h index b3b149dcbf96..55a4abaf6715 100644 --- a/include/linux/mount.h +++ b/include/linux/mount.h @@ -108,6 +108,18 @@ extern void mark_mounts_for_expiry(struct list_head *mounts); extern dev_t name_to_dev_t(const char *name); extern bool path_is_mountpoint(const struct path *path); +extern bool our_mnt(struct vfsmount *mnt); + +extern struct vfsmount *kern_mount(struct file_system_type *); +extern void kern_unmount(struct vfsmount *mnt); +extern int may_umount_tree(struct vfsmount *); +extern int may_umount(struct vfsmount *); +extern long do_mount(const char *, const char __user *, + const char *, unsigned long, void *); +extern struct vfsmount *collect_mounts(const struct path *); +extern void drop_collected_mounts(struct vfsmount *); +extern int iterate_mounts(int (*)(struct vfsmount *, void *), void *, + struct vfsmount *); extern void kern_unmount_array(struct vfsmount *mnt[], unsigned int num); #endif /* _LINUX_MOUNT_H */ diff --git a/security/smack/smackfs.c b/security/smack/smackfs.c index 658eab05599e..192f33cc601e 100644 --- a/security/smack/smackfs.c +++ b/security/smack/smackfs.c @@ -23,6 +23,7 @@ #include #include #include +#include #include #include "smack.h" -- cgit v1.2.3