enum {Enabled, Magic};
#define MISC_FMT_PRESERVE_ARGV0 (1<<31)
+#define MISC_FMT_OPEN_BINARY (1<<30)
+#define MISC_FMT_CREDENTIALS (1<<29)
typedef struct {
struct list_head list;
struct dentry *dentry;
} Node;
-static rwlock_t entries_lock = RW_LOCK_UNLOCKED;
+static DEFINE_RWLOCK(entries_lock);
+static struct file_system_type bm_fs_type;
static struct vfsmount *bm_mnt;
static int entry_count;
static int load_misc_binary(struct linux_binprm *bprm, struct pt_regs *regs)
{
Node *fmt;
- struct file * file;
+ struct file * interp_file = NULL;
char iname[BINPRM_BUF_SIZE];
char *iname_addr = iname;
int retval;
+ int fd_binary = -1;
+ struct files_struct *files = NULL;
retval = -ENOEXEC;
if (!enabled)
if (!fmt)
goto _ret;
- allow_write_access(bprm->file);
- fput(bprm->file);
- bprm->file = NULL;
-
- /* Build args for interpreter */
if (!(fmt->flags & MISC_FMT_PRESERVE_ARGV0)) {
remove_arg_zero(bprm);
}
- retval = copy_strings_kernel(1, &bprm->interp, bprm);
- if (retval < 0) goto _ret;
- bprm->argc++;
- retval = copy_strings_kernel(1, &iname_addr, bprm);
- if (retval < 0) goto _ret;
+
+ if (fmt->flags & MISC_FMT_OPEN_BINARY) {
+
+ files = current->files;
+ retval = unshare_files();
+ if (retval < 0)
+ goto _ret;
+ if (files == current->files) {
+ put_files_struct(files);
+ files = NULL;
+ }
+ /* if the binary should be opened on behalf of the
+ * interpreter than keep it open and assign descriptor
+ * to it */
+ fd_binary = get_unused_fd();
+ if (fd_binary < 0) {
+ retval = fd_binary;
+ goto _unshare;
+ }
+ fd_install(fd_binary, bprm->file);
+
+ /* if the binary is not readable than enforce mm->dumpable=0
+ regardless of the interpreter's permissions */
+ if (file_permission(bprm->file, MAY_READ))
+ bprm->interp_flags |= BINPRM_FLAGS_ENFORCE_NONDUMP;
+
+ allow_write_access(bprm->file);
+ bprm->file = NULL;
+
+ /* mark the bprm that fd should be passed to interp */
+ bprm->interp_flags |= BINPRM_FLAGS_EXECFD;
+ bprm->interp_data = fd_binary;
+
+ } else {
+ allow_write_access(bprm->file);
+ fput(bprm->file);
+ bprm->file = NULL;
+ }
+ /* make argv[1] be the path to the binary */
+ retval = copy_strings_kernel (1, &bprm->interp, bprm);
+ if (retval < 0)
+ goto _error;
bprm->argc++;
- bprm->interp = iname; /* for binfmt_script */
- file = open_exec(iname);
- retval = PTR_ERR(file);
- if (IS_ERR(file))
- goto _ret;
- bprm->file = file;
+ /* add the interp as argv[0] */
+ retval = copy_strings_kernel (1, &iname_addr, bprm);
+ if (retval < 0)
+ goto _error;
+ bprm->argc ++;
+
+ bprm->interp = iname; /* for binfmt_script */
- retval = prepare_binprm(bprm);
- if (retval >= 0)
- retval = search_binary_handler(bprm, regs);
+ interp_file = open_exec (iname);
+ retval = PTR_ERR (interp_file);
+ if (IS_ERR (interp_file))
+ goto _error;
+
+ bprm->file = interp_file;
+ if (fmt->flags & MISC_FMT_CREDENTIALS) {
+ /*
+ * No need to call prepare_binprm(), it's already been
+ * done. bprm->buf is stale, update from interp_file.
+ */
+ memset(bprm->buf, 0, BINPRM_BUF_SIZE);
+ retval = kernel_read(bprm->file, 0, bprm->buf, BINPRM_BUF_SIZE);
+ } else
+ retval = prepare_binprm (bprm);
+
+ if (retval < 0)
+ goto _error;
+
+ retval = search_binary_handler (bprm, regs);
+ if (retval < 0)
+ goto _error;
+
+ if (files) {
+ put_files_struct(files);
+ files = NULL;
+ }
_ret:
return retval;
+_error:
+ if (fd_binary > 0)
+ sys_close(fd_binary);
+ bprm->interp_flags = 0;
+ bprm->interp_data = 0;
+_unshare:
+ if (files)
+ reset_files_struct(current, files);
+ goto _ret;
}
/* Command parsers */
return p - from;
}
+static char * check_special_flags (char * sfs, Node * e)
+{
+ char * p = sfs;
+ int cont = 1;
+
+ /* special flags */
+ while (cont) {
+ switch (*p) {
+ case 'P':
+ p++;
+ e->flags |= MISC_FMT_PRESERVE_ARGV0;
+ break;
+ case 'O':
+ p++;
+ e->flags |= MISC_FMT_OPEN_BINARY;
+ break;
+ case 'C':
+ p++;
+ /* this flags also implies the
+ open-binary flag */
+ e->flags |= (MISC_FMT_CREDENTIALS |
+ MISC_FMT_OPEN_BINARY);
+ break;
+ default:
+ cont = 0;
+ }
+ }
+
+ return p;
+}
/*
* This registers a new binary format, it recognises the syntax
- * ':name:type:offset:magic:mask:interpreter:'
+ * ':name:type:offset:magic:mask:interpreter:flags'
* where the ':' is the IFS, that can be chosen with the first char
*/
static Node *create_entry(const char __user *buffer, size_t count)
err = -ENOMEM;
memsize = sizeof(Node) + count + 8;
- e = (Node *) kmalloc(memsize, GFP_USER);
+ e = kmalloc(memsize, GFP_USER);
if (!e)
goto out;
if (!e->interpreter[0])
goto Einval;
- if (*p == 'P') {
- p++;
- e->flags |= MISC_FMT_PRESERVE_ARGV0;
- }
+
+ p = check_special_flags (p, e);
if (*p == '\n')
p++;
{
char *dp;
char *status = "disabled";
+ const char * flags = "flags: ";
if (test_bit(Enabled, &e->flags))
status = "enabled";
sprintf(page, "%s\ninterpreter %s\n", status, e->interpreter);
dp = page + strlen(page);
+
+ /* print the special flags */
+ sprintf (dp, "%s", flags);
+ dp += strlen (flags);
+ if (e->flags & MISC_FMT_PRESERVE_ARGV0) {
+ *dp ++ = 'P';
+ }
+ if (e->flags & MISC_FMT_OPEN_BINARY) {
+ *dp ++ = 'O';
+ }
+ if (e->flags & MISC_FMT_CREDENTIALS) {
+ *dp ++ = 'C';
+ }
+ *dp ++ = '\n';
+
+
if (!test_bit(Magic, &e->flags)) {
sprintf(dp, "extension .%s\n", e->magic);
} else {
inode->i_mode = mode;
inode->i_uid = 0;
inode->i_gid = 0;
- inode->i_blksize = PAGE_CACHE_SIZE;
inode->i_blocks = 0;
- inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME;
+ inode->i_atime = inode->i_mtime = inode->i_ctime =
+ current_fs_time(inode->i_sb);
}
return inode;
}
static void bm_clear_inode(struct inode *inode)
{
- kfree(inode->u.generic_ip);
+ kfree(inode->i_private);
}
static void kill_node(Node *e)
static ssize_t
bm_entry_read(struct file * file, char __user * buf, size_t nbytes, loff_t *ppos)
{
- Node *e = file->f_dentry->d_inode->u.generic_ip;
+ Node *e = file->f_path.dentry->d_inode->i_private;
loff_t pos = *ppos;
ssize_t res;
char *page;
size_t count, loff_t *ppos)
{
struct dentry *root;
- Node *e = file->f_dentry->d_inode->u.generic_ip;
+ Node *e = file->f_path.dentry->d_inode->i_private;
int res = parse_command(buffer, count);
switch (res) {
break;
case 2: set_bit(Enabled, &e->flags);
break;
- case 3: root = dget(file->f_vfsmnt->mnt_sb->s_root);
- down(&root->d_inode->i_sem);
+ case 3: root = dget(file->f_path.mnt->mnt_sb->s_root);
+ mutex_lock(&root->d_inode->i_mutex);
kill_node(e);
- up(&root->d_inode->i_sem);
+ mutex_unlock(&root->d_inode->i_mutex);
dput(root);
break;
default: return res;
return count;
}
-static struct file_operations bm_entry_operations = {
+static const struct file_operations bm_entry_operations = {
.read = bm_entry_read,
.write = bm_entry_write,
};
Node *e;
struct inode *inode;
struct dentry *root, *dentry;
- struct super_block *sb = file->f_vfsmnt->mnt_sb;
+ struct super_block *sb = file->f_path.mnt->mnt_sb;
int err = 0;
e = create_entry(buffer, count);
return PTR_ERR(e);
root = dget(sb->s_root);
- down(&root->d_inode->i_sem);
+ mutex_lock(&root->d_inode->i_mutex);
dentry = lookup_one_len(e->name, root, strlen(e->name));
err = PTR_ERR(dentry);
if (IS_ERR(dentry))
if (!inode)
goto out2;
- err = simple_pin_fs("binfmt_misc", &bm_mnt, &entry_count);
+ err = simple_pin_fs(&bm_fs_type, &bm_mnt, &entry_count);
if (err) {
iput(inode);
inode = NULL;
}
e->dentry = dget(dentry);
- inode->u.generic_ip = e;
+ inode->i_private = e;
inode->i_fop = &bm_entry_operations;
d_instantiate(dentry, inode);
out2:
dput(dentry);
out:
- up(&root->d_inode->i_sem);
+ mutex_unlock(&root->d_inode->i_mutex);
dput(root);
if (err) {
return count;
}
-static struct file_operations bm_register_operations = {
+static const struct file_operations bm_register_operations = {
.write = bm_register_write,
};
switch (res) {
case 1: enabled = 0; break;
case 2: enabled = 1; break;
- case 3: root = dget(file->f_vfsmnt->mnt_sb->s_root);
- down(&root->d_inode->i_sem);
+ case 3: root = dget(file->f_path.mnt->mnt_sb->s_root);
+ mutex_lock(&root->d_inode->i_mutex);
while (!list_empty(&entries))
kill_node(list_entry(entries.next, Node, list));
- up(&root->d_inode->i_sem);
+ mutex_unlock(&root->d_inode->i_mutex);
dput(root);
default: return res;
}
return count;
}
-static struct file_operations bm_status_operations = {
+static const struct file_operations bm_status_operations = {
.read = bm_status_read,
.write = bm_status_write,
};
return err;
}
-static struct super_block *bm_get_sb(struct file_system_type *fs_type,
- int flags, const char *dev_name, void *data)
+static int bm_get_sb(struct file_system_type *fs_type,
+ int flags, const char *dev_name, void *data, struct vfsmount *mnt)
{
- return get_sb_single(fs_type, flags, data, bm_fill_super);
+ return get_sb_single(fs_type, flags, data, bm_fill_super, mnt);
}
static struct linux_binfmt misc_format = {
git://git.onelab.eu / linux-2.6.git / blobdiff