--- /dev/null
+diff -rup linux-2.6.5.orig/fs/filesystems.c linux-2.6.5/fs/filesystems.c
+--- linux-2.6.5.orig/fs/filesystems.c 2003-12-18 03:59:18.000000000 +0100
++++ linux-2.6.5/fs/filesystems.c 2004-04-05 10:54:37.000000000 +0200
+@@ -222,7 +222,8 @@ struct file_system_type *get_fs_type(con
+ if (fs && !try_module_get(fs->owner))
+ fs = NULL;
+ read_unlock(&file_systems_lock);
+- if (!fs && (request_module("%s", name) == 0)) {
++ if (!fs && capable(CAP_SYS_ADMIN) &&
++ (request_module("%s", name) == 0)) {
+ read_lock(&file_systems_lock);
+ fs = *(find_filesystem(name));
+ if (fs && !try_module_get(fs->owner))
+diff -rup linux-2.6.5.orig/fs/namespace.c linux-2.6.5/fs/namespace.c
+--- linux-2.6.5.orig/fs/namespace.c 2004-04-05 10:50:46.000000000 +0200
++++ linux-2.6.5/fs/namespace.c 2004-04-05 10:54:37.000000000 +0200
+@@ -25,13 +25,16 @@
+
+ extern int __init init_rootfs(void);
+ extern int __init sysfs_init(void);
++extern void put_filesystem(struct file_system_type *fs);
++
++#define MAX_MOUNTS 256
+
+ /* spinlock for vfsmount related operations, inplace of dcache_lock */
+ spinlock_t vfsmount_lock __cacheline_aligned_in_smp = SPIN_LOCK_UNLOCKED;
+ static struct list_head *mount_hashtable;
+ static int hash_mask, hash_bits;
+ static kmem_cache_t *mnt_cache;
+-
++struct mounts_stat_struct mounts_stat = { .max_mounts = MAX_MOUNTS };
+ static inline unsigned long hash(struct vfsmount *mnt, struct dentry *dentry)
+ {
+ unsigned long tmp = ((unsigned long) mnt / L1_CACHE_BYTES);
+@@ -40,10 +43,38 @@ static inline unsigned long hash(struct
+ return tmp & hash_mask;
+ }
+
++static inline int inc_nr_mounts(void)
++{
++ int err = 0;
++ spin_lock(&vfsmount_lock);
++ if (capable(CAP_SYS_ADMIN) ||
++ mounts_stat.nr_mounts < mounts_stat.max_mounts)
++ mounts_stat.nr_mounts++;
++ else
++ err = mounts_stat.max_mounts ? -EMFILE : -EPERM;
++ spin_unlock(&vfsmount_lock);
++ return err;
++}
++
++static inline void dec_nr_mounts(void)
++{
++ spin_lock(&vfsmount_lock);
++ mounts_stat.nr_mounts--;
++ spin_unlock(&vfsmount_lock);
++}
++
+ struct vfsmount *alloc_vfsmnt(const char *name)
+ {
+- struct vfsmount *mnt = kmem_cache_alloc(mnt_cache, GFP_KERNEL);
+- if (mnt) {
++ struct vfsmount *mnt;
++ int err = inc_nr_mounts();
++ if (err)
++ return ERR_PTR(err);
++
++ mnt = kmem_cache_alloc(mnt_cache, GFP_KERNEL);
++ if (!mnt) {
++ dec_nr_mounts();
++ return ERR_PTR(-ENOMEM);
++ } else {
+ memset(mnt, 0, sizeof(struct vfsmount));
+ atomic_set(&mnt->mnt_count,1);
+ INIT_LIST_HEAD(&mnt->mnt_hash);
+@@ -66,6 +97,7 @@ void free_vfsmnt(struct vfsmount *mnt)
+ {
+ kfree(mnt->mnt_devname);
+ kmem_cache_free(mnt_cache, mnt);
++ dec_nr_mounts();
+ }
+
+ /*
+@@ -147,13 +179,14 @@ clone_mnt(struct vfsmount *old, struct d
+ struct super_block *sb = old->mnt_sb;
+ struct vfsmount *mnt = alloc_vfsmnt(old->mnt_devname);
+
+- if (mnt) {
++ if (!IS_ERR(mnt)) {
+ mnt->mnt_flags = old->mnt_flags;
+ atomic_inc(&sb->s_active);
+ mnt->mnt_sb = sb;
+ mnt->mnt_root = dget(root);
+ mnt->mnt_mountpoint = mnt->mnt_root;
+ mnt->mnt_parent = mnt;
++ mnt->user = capable(CAP_SYS_ADMIN) ? 0 : current->fsuid;
+ }
+ return mnt;
+ }
+@@ -238,6 +271,8 @@ static int show_vfsmnt(struct seq_file *
+ if (mnt->mnt_flags & fs_infop->flag)
+ seq_puts(m, fs_infop->str);
+ }
++ if (mnt->user)
++ seq_printf(m, ",user=%i", mnt->user);
+ if (mnt->mnt_sb->s_op->show_options)
+ err = mnt->mnt_sb->s_op->show_options(m, mnt);
+ seq_puts(m, " 0 0\n");
+@@ -388,8 +423,10 @@ asmlinkage long sys_umount(char __user *
+ goto dput_and_out;
+
+ retval = -EPERM;
+- if (!capable(CAP_SYS_ADMIN))
+- goto dput_and_out;
++ if (!capable(CAP_SYS_ADMIN)) {
++ if(nd.mnt->user != current->fsuid || (flags & MNT_FORCE))
++ goto dput_and_out;
++ }
+
+ retval = do_umount(nd.mnt, flags);
+ dput_and_out:
+@@ -409,20 +446,15 @@ asmlinkage long sys_oldumount(char __use
+
+ static int mount_is_safe(struct nameidata *nd)
+ {
+- if (capable(CAP_SYS_ADMIN))
+- return 0;
+- return -EPERM;
+-#ifdef notyet
+- if (S_ISLNK(nd->dentry->d_inode->i_mode))
+- return -EPERM;
+- if (nd->dentry->d_inode->i_mode & S_ISVTX) {
+- if (current->uid != nd->dentry->d_inode->i_uid)
++ if (!capable(CAP_SYS_ADMIN)) {
++ if (!S_ISDIR(nd->dentry->d_inode->i_mode) &&
++ !S_ISREG(nd->dentry->d_inode->i_mode))
++ return -EPERM;
++ if (current->fsuid != nd->dentry->d_inode->i_uid ||
++ permission(nd->dentry->d_inode, MAY_WRITE, nd))
+ return -EPERM;
+ }
+- if (permission(nd->dentry->d_inode, MAY_WRITE, nd))
+- return -EPERM;
+ return 0;
+-#endif
+ }
+
+ static int
+@@ -444,8 +476,8 @@ static struct vfsmount *copy_tree(struct
+ struct nameidata nd;
+
+ res = q = clone_mnt(mnt, dentry);
+- if (!q)
+- goto Enomem;
++ if (IS_ERR(q))
++ goto out_error;
+ q->mnt_mountpoint = mnt->mnt_mountpoint;
+
+ p = mnt;
+@@ -463,8 +495,8 @@ static struct vfsmount *copy_tree(struct
+ nd.mnt = q;
+ nd.dentry = p->mnt_mountpoint;
+ q = clone_mnt(p, p->mnt_root);
+- if (!q)
+- goto Enomem;
++ if (IS_ERR(q))
++ goto out_error;
+ spin_lock(&vfsmount_lock);
+ list_add_tail(&q->mnt_list, &res->mnt_list);
+ attach_mnt(q, &nd);
+@@ -472,13 +504,13 @@ static struct vfsmount *copy_tree(struct
+ }
+ }
+ return res;
+- Enomem:
++ out_error:
+ if (res) {
+ spin_lock(&vfsmount_lock);
+ umount_tree(res);
+ spin_unlock(&vfsmount_lock);
+ }
+- return NULL;
++ return q;
+ }
+
+ static int graft_tree(struct vfsmount *mnt, struct nameidata *nd)
+@@ -538,11 +570,14 @@ static int do_loopback(struct nameidata
+ down_write(¤t->namespace->sem);
+ err = -EINVAL;
+ if (check_mnt(nd->mnt) && (!recurse || check_mnt(old_nd.mnt))) {
+- err = -ENOMEM;
+ if (recurse)
+ mnt = copy_tree(old_nd.mnt, old_nd.dentry);
+ else
+ mnt = clone_mnt(old_nd.mnt, old_nd.dentry);
++ if (IS_ERR(mnt)) {
++ err = PTR_ERR(mnt);
++ goto out;
++ }
+ }
+
+ if (mnt) {
+@@ -555,6 +590,7 @@ static int do_loopback(struct nameidata
+ mntput(mnt);
+ }
+
++ out:
+ up_write(¤t->namespace->sem);
+ path_release(&old_nd);
+ return err;
+@@ -654,14 +690,28 @@ static int do_add_mount(struct nameidata
+ int mnt_flags, char *name, void *data)
+ {
+ struct vfsmount *mnt;
+- int err;
++ int err = mount_is_safe(nd);
++ if(err)
++ return err;
+
+ if (!type || !memchr(type, 0, PAGE_SIZE))
+ return -EINVAL;
+
+ /* we need capabilities... */
+- if (!capable(CAP_SYS_ADMIN))
+- return -EPERM;
++ if (!capable(CAP_SYS_ADMIN)) {
++ /* but allow "safe" filesystems anyway */
++ int issafe = 0;
++ struct file_system_type *t = get_fs_type(type);
++ if(t) {
++ issafe = t->fs_flags & FS_SAFE;
++ put_filesystem(t);
++ }
++ if(!issafe)
++ return -EPERM;
++
++ /* users should not have suid or dev files */
++ mnt_flags |= (MNT_NOSUID | MNT_NODEV);
++ }
+
+ mnt = do_kern_mount(type, flags, name, data);
+ err = PTR_ERR(mnt);
+@@ -801,6 +851,7 @@ int copy_namespace(int flags, struct tas
+ struct namespace *new_ns;
+ struct vfsmount *rootmnt = NULL, *pwdmnt = NULL, *altrootmnt = NULL;
+ struct fs_struct *fs = tsk->fs;
++ int err;
+
+ if (!namespace)
+ return 0;
+@@ -810,11 +861,7 @@ int copy_namespace(int flags, struct tas
+ if (!(flags & CLONE_NEWNS))
+ return 0;
+
+- if (!capable(CAP_SYS_ADMIN)) {
+- put_namespace(namespace);
+- return -EPERM;
+- }
+-
++ err = -ENOMEM;
+ new_ns = kmalloc(sizeof(struct namespace), GFP_KERNEL);
+ if (!new_ns)
+ goto out;
+@@ -826,7 +873,8 @@ int copy_namespace(int flags, struct tas
+ down_write(&tsk->namespace->sem);
+ /* First pass: copy the tree topology */
+ new_ns->root = copy_tree(namespace->root, namespace->root->mnt_root);
+- if (!new_ns->root) {
++ if (IS_ERR(new_ns->root)) {
++ err = PTR_ERR(new_ns->root);
+ up_write(&tsk->namespace->sem);
+ kfree(new_ns);
+ goto out;
+@@ -876,7 +924,7 @@ int copy_namespace(int flags, struct tas
+
+ out:
+ put_namespace(namespace);
+- return -ENOMEM;
++ return err;
+ }
+
+ asmlinkage long sys_mount(char __user * dev_name, char __user * dir_name,
+diff -rup linux-2.6.5.orig/fs/super.c linux-2.6.5/fs/super.c
+--- linux-2.6.5.orig/fs/super.c 2004-04-05 10:50:46.000000000 +0200
++++ linux-2.6.5/fs/super.c 2004-04-05 11:02:10.000000000 +0200
+@@ -726,7 +726,7 @@ struct vfsmount *
+ do_kern_mount(const char *fstype, int flags, const char *name, void *data)
+ {
+ struct file_system_type *type = get_fs_type(fstype);
+- struct super_block *sb = ERR_PTR(-ENOMEM);
++ struct super_block *sb;
+ struct vfsmount *mnt;
+ int error;
+ char *secdata = NULL;
+@@ -735,24 +735,23 @@ do_kern_mount(const char *fstype, int fl
+ return ERR_PTR(-ENODEV);
+
+ mnt = alloc_vfsmnt(name);
+- if (!mnt)
++ error = PTR_ERR(mnt);
++ if (IS_ERR(mnt))
+ goto out;
+
+ if (data) {
+ secdata = alloc_secdata();
+- if (!secdata) {
+- sb = ERR_PTR(-ENOMEM);
++ error = -ENOMEM;
++ if (!secdata)
+ goto out_mnt;
+- }
+
+ error = security_sb_copy_data(type, data, secdata);
+- if (error) {
+- sb = ERR_PTR(error);
++ if (error)
+ goto out_free_secdata;
+- }
+ }
+
+ sb = type->get_sb(type, flags, name, data);
++ error = PTR_ERR(sb);
+ if (IS_ERR(sb))
+ goto out_free_secdata;
+ error = security_sb_kern_mount(sb, secdata);
+@@ -762,20 +761,20 @@ do_kern_mount(const char *fstype, int fl
+ mnt->mnt_root = dget(sb->s_root);
+ mnt->mnt_mountpoint = sb->s_root;
+ mnt->mnt_parent = mnt;
++ mnt->user = capable(CAP_SYS_ADMIN) ? 0 : current->fsuid;
+ up_write(&sb->s_umount);
+ put_filesystem(type);
+ return mnt;
+ out_sb:
+ up_write(&sb->s_umount);
+ deactivate_super(sb);
+- sb = ERR_PTR(error);
+ out_free_secdata:
+ free_secdata(secdata);
+ out_mnt:
+ free_vfsmnt(mnt);
+ out:
+ put_filesystem(type);
+- return (struct vfsmount *)sb;
++ return ERR_PTR(error);
+ }
+
+ struct vfsmount *kern_mount(struct file_system_type *type)
+diff -rup linux-2.6.5.orig/include/linux/fs.h linux-2.6.5/include/linux/fs.h
+--- linux-2.6.5.orig/include/linux/fs.h 2004-04-05 10:50:50.000000000 +0200
++++ linux-2.6.5/include/linux/fs.h 2004-04-05 11:03:55.000000000 +0200
+@@ -55,6 +55,12 @@ struct files_stat_struct {
+ };
+ extern struct files_stat_struct files_stat;
+
++struct mounts_stat_struct {
++ int nr_mounts;
++ int max_mounts;
++};
++extern struct mounts_stat_struct mounts_stat;
++
+ struct inodes_stat_t {
+ int nr_inodes;
+ int nr_unused;
+@@ -90,6 +96,7 @@ extern int leases_enable, dir_notify_ena
+ /* public flags for file_system_type */
+ #define FS_REQUIRES_DEV 1
+ #define FS_BINARY_MOUNTDATA 2
++#define FS_SAFE 4 /* Safe to mount by user */
+ #define FS_REVAL_DOT 16384 /* Check the paths ".", ".." for staleness */
+ #define FS_ODD_RENAME 32768 /* Temporary stuff; will go away as soon
+ * as nfs_rename() will be cleaned up
+diff -rup linux-2.6.5.orig/include/linux/mount.h linux-2.6.5/include/linux/mount.h
+--- linux-2.6.5.orig/include/linux/mount.h 2003-12-18 03:58:08.000000000 +0100
++++ linux-2.6.5/include/linux/mount.h 2004-04-05 10:54:37.000000000 +0200
+@@ -30,6 +30,7 @@ struct vfsmount
+ atomic_t mnt_count;
+ int mnt_flags;
+ char *mnt_devname; /* Name of device e.g. /dev/dsk/hda1 */
++ uid_t user;
+ struct list_head mnt_list;
+ };
+
+diff -rup linux-2.6.5.orig/include/linux/sysctl.h linux-2.6.5/include/linux/sysctl.h
+--- linux-2.6.5.orig/include/linux/sysctl.h 2004-04-05 10:50:50.000000000 +0200
++++ linux-2.6.5/include/linux/sysctl.h 2004-04-05 10:54:37.000000000 +0200
+@@ -624,8 +624,8 @@ enum
+ FS_NRFILE=6, /* int:current number of allocated filedescriptors */
+ FS_MAXFILE=7, /* int:maximum number of filedescriptors that can be allocated */
+ FS_DENTRY=8,
+- FS_NRSUPER=9, /* int:current number of allocated super_blocks */
+- FS_MAXSUPER=10, /* int:maximum number of super_blocks that can be allocated */
++ FS_NRMOUNT=9, /* int:current number of mounts */
++ FS_MAXMOUNT=10, /* int:maximum number of mounts allowed */
+ FS_OVERFLOWUID=11, /* int: overflow UID */
+ FS_OVERFLOWGID=12, /* int: overflow GID */
+ FS_LEASES=13, /* int: leases enabled */
+diff -rup linux-2.6.5.orig/kernel/sysctl.c linux-2.6.5/kernel/sysctl.c
+--- linux-2.6.5.orig/kernel/sysctl.c 2004-04-05 10:50:51.000000000 +0200
++++ linux-2.6.5/kernel/sysctl.c 2004-04-05 10:54:37.000000000 +0200
+@@ -793,6 +793,22 @@ static ctl_table fs_table[] = {
+ .proc_handler = &proc_dointvec,
+ },
+ {
++ .ctl_name = FS_NRMOUNT,
++ .procname = "mount-nr",
++ .data = &mounts_stat.nr_mounts,
++ .maxlen = sizeof(int),
++ .mode = 0444,
++ .proc_handler = &proc_dointvec,
++ },
++ {
++ .ctl_name = FS_MAXMOUNT,
++ .procname = "mount-max",
++ .data = &mounts_stat.max_mounts,
++ .maxlen = sizeof(int),
++ .mode = 0644,
++ .proc_handler = &proc_dointvec,
++ },
++ {
+ .ctl_name = FS_OVERFLOWUID,
+ .procname = "overflowuid",
+ .data = &fs_overflowuid,
projects / qemu-gpiodev / libfuse.git / commitdiff