From 5e6123f3477e4260fb14392f0a88f1a842fa4d42 Mon Sep 17 00:00:00 2001 From: Seunghun Lee Date: Sun, 14 Sep 2014 22:15:10 +0900 Subject: [PATCH] vfs: move getname() from callers to do_mount() It would make more sense to pass char __user * instead of char * in callers of do_mount() and do getname() inside do_mount(). Suggested-by: Al Viro Signed-off-by: Seunghun Lee Signed-off-by: Al Viro --- arch/alpha/kernel/osf_sys.c | 23 ++++++++++------------- fs/compat.c | 20 ++++++-------------- fs/namespace.c | 19 +++---------------- include/linux/fs.h | 3 ++- 4 files changed, 21 insertions(+), 44 deletions(-) diff --git a/arch/alpha/kernel/osf_sys.c b/arch/alpha/kernel/osf_sys.c index 1402fcc..f9c732e 100644 --- a/arch/alpha/kernel/osf_sys.c +++ b/arch/alpha/kernel/osf_sys.c @@ -446,7 +446,8 @@ struct procfs_args { * unhappy with OSF UFS. [CHECKME] */ static int -osf_ufs_mount(const char *dirname, struct ufs_args __user *args, int flags) +osf_ufs_mount(const char __user *dirname, + struct ufs_args __user *args, int flags) { int retval; struct cdfs_args tmp; @@ -466,7 +467,8 @@ osf_ufs_mount(const char *dirname, struct ufs_args __user *args, int flags) } static int -osf_cdfs_mount(const char *dirname, struct cdfs_args __user *args, int flags) +osf_cdfs_mount(const char __user *dirname, + struct cdfs_args __user *args, int flags) { int retval; struct cdfs_args tmp; @@ -486,7 +488,8 @@ osf_cdfs_mount(const char *dirname, struct cdfs_args __user *args, int flags) } static int -osf_procfs_mount(const char *dirname, struct procfs_args __user *args, int flags) +osf_procfs_mount(const char __user *dirname, + struct procfs_args __user *args, int flags) { struct procfs_args tmp; @@ -500,28 +503,22 @@ SYSCALL_DEFINE4(osf_mount, unsigned long, typenr, const char __user *, path, int, flag, void __user *, data) { int retval; - struct filename *name; - name = getname(path); - retval = PTR_ERR(name); - if (IS_ERR(name)) - goto out; switch (typenr) { case 1: - retval = osf_ufs_mount(name->name, data, flag); + retval = osf_ufs_mount(path, data, flag); break; case 6: - retval = osf_cdfs_mount(name->name, data, flag); + retval = osf_cdfs_mount(path, data, flag); break; case 9: - retval = osf_procfs_mount(name->name, data, flag); + retval = osf_procfs_mount(path, data, flag); break; default: retval = -EINVAL; printk("osf_mount(%ld, %x)\n", typenr, flag); } - putname(name); - out: + return retval; } diff --git a/fs/compat.c b/fs/compat.c index 6205c24..b13df99 100644 --- a/fs/compat.c +++ b/fs/compat.c @@ -794,7 +794,6 @@ COMPAT_SYSCALL_DEFINE5(mount, const char __user *, dev_name, char *kernel_type; unsigned long data_page; char *kernel_dev; - struct filename *dir; int retval; kernel_type = copy_mount_string(type); @@ -802,19 +801,14 @@ COMPAT_SYSCALL_DEFINE5(mount, const char __user *, dev_name, if (IS_ERR(kernel_type)) goto out; - dir = getname(dir_name); - retval = PTR_ERR(dir); - if (IS_ERR(dir)) - goto out1; - kernel_dev = copy_mount_string(dev_name); retval = PTR_ERR(kernel_dev); if (IS_ERR(kernel_dev)) - goto out2; + goto out1; retval = copy_mount_options(data, &data_page); if (retval < 0) - goto out3; + goto out2; retval = -EINVAL; @@ -823,19 +817,17 @@ COMPAT_SYSCALL_DEFINE5(mount, const char __user *, dev_name, do_ncp_super_data_conv((void *)data_page); } else if (!strcmp(kernel_type, NFS4_NAME)) { if (do_nfs4_super_data_conv((void *) data_page)) - goto out4; + goto out3; } } - retval = do_mount(kernel_dev, dir->name, kernel_type, + retval = do_mount(kernel_dev, dir_name, kernel_type, flags, (void*)data_page); - out4: - free_page(data_page); out3: - kfree(kernel_dev); + free_page(data_page); out2: - putname(dir); + kfree(kernel_dev); out1: kfree(kernel_type); out: diff --git a/fs/namespace.c b/fs/namespace.c index abd3abb..348562f 100644 --- a/fs/namespace.c +++ b/fs/namespace.c @@ -2533,7 +2533,7 @@ char *copy_mount_string(const void __user *data) * Therefore, if this magic number is present, it carries no information * and must be discarded. */ -long do_mount(const char *dev_name, const char *dir_name, +long do_mount(const char *dev_name, const char __user *dir_name, const char *type_page, unsigned long flags, void *data_page) { struct path path; @@ -2545,15 +2545,11 @@ long do_mount(const char *dev_name, const char *dir_name, flags &= ~MS_MGC_MSK; /* Basic sanity checks */ - - if (!dir_name || !*dir_name || !memchr(dir_name, 0, PAGE_SIZE)) - return -EINVAL; - if (data_page) ((char *)data_page)[PAGE_SIZE - 1] = 0; /* ... and get the mountpoint */ - retval = kern_path(dir_name, LOOKUP_FOLLOW, &path); + retval = user_path(dir_name, &path); if (retval) return retval; @@ -2778,7 +2774,6 @@ SYSCALL_DEFINE5(mount, char __user *, dev_name, char __user *, dir_name, { int ret; char *kernel_type; - struct filename *kernel_dir; char *kernel_dev; unsigned long data_page; @@ -2787,12 +2782,6 @@ SYSCALL_DEFINE5(mount, char __user *, dev_name, char __user *, dir_name, if (IS_ERR(kernel_type)) goto out_type; - kernel_dir = getname(dir_name); - if (IS_ERR(kernel_dir)) { - ret = PTR_ERR(kernel_dir); - goto out_dir; - } - kernel_dev = copy_mount_string(dev_name); ret = PTR_ERR(kernel_dev); if (IS_ERR(kernel_dev)) @@ -2802,15 +2791,13 @@ SYSCALL_DEFINE5(mount, char __user *, dev_name, char __user *, dir_name, if (ret < 0) goto out_data; - ret = do_mount(kernel_dev, kernel_dir->name, kernel_type, flags, + ret = do_mount(kernel_dev, dir_name, kernel_type, flags, (void *) data_page); free_page(data_page); out_data: kfree(kernel_dev); out_dev: - putname(kernel_dir); -out_dir: kfree(kernel_type); out_type: return ret; diff --git a/include/linux/fs.h b/include/linux/fs.h index 75bdd51..9214836 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -1855,7 +1855,8 @@ extern struct vfsmount *kern_mount_data(struct file_system_type *, void *data); 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 *, const char *, unsigned long, void *); +extern long do_mount(const char *, const char __user *, + const char *, unsigned long, void *); extern struct vfsmount *collect_mounts(struct path *); extern void drop_collected_mounts(struct vfsmount *); extern int iterate_mounts(int (*)(struct vfsmount *, void *), void *, -- 2.7.4