Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
diff --git a/fs/binfmt_misc.c b/fs/binfmt_misc.c
new file mode 100644
index 0000000..8ae0db6
--- /dev/null
+++ b/fs/binfmt_misc.c
@@ -0,0 +1,780 @@
+/*
+ * binfmt_misc.c
+ *
+ * Copyright (C) 1997 Richard Günther
+ *
+ * binfmt_misc detects binaries via a magic or filename extension and invokes
+ * a specified wrapper. This should obsolete binfmt_java, binfmt_em86 and
+ * binfmt_mz.
+ *
+ * 1997-04-25 first version
+ * [...]
+ * 1997-05-19 cleanup
+ * 1997-06-26 hpa: pass the real filename rather than argv[0]
+ * 1997-06-30 minor cleanup
+ * 1997-08-09 removed extension stripping, locking cleanup
+ * 2001-02-28 AV: rewritten into something that resembles C. Original didn't.
+ */
+
+#include <linux/module.h>
+#include <linux/init.h>
+
+#include <linux/binfmts.h>
+#include <linux/slab.h>
+#include <linux/ctype.h>
+#include <linux/file.h>
+#include <linux/pagemap.h>
+#include <linux/namei.h>
+#include <linux/mount.h>
+#include <linux/syscalls.h>
+
+#include <asm/uaccess.h>
+
+enum {
+ VERBOSE_STATUS = 1 /* make it zero to save 400 bytes kernel memory */
+};
+
+static LIST_HEAD(entries);
+static int enabled = 1;
+
+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;
+ unsigned long flags; /* type, status, etc. */
+ int offset; /* offset of magic */
+ int size; /* size of magic/mask */
+ char *magic; /* magic or filename extension */
+ char *mask; /* mask, NULL for exact match */
+ char *interpreter; /* filename of interpreter */
+ char *name;
+ struct dentry *dentry;
+} Node;
+
+static DEFINE_RWLOCK(entries_lock);
+static struct vfsmount *bm_mnt;
+static int entry_count;
+
+/*
+ * Check if we support the binfmt
+ * if we do, return the node, else NULL
+ * locking is done in load_misc_binary
+ */
+static Node *check_file(struct linux_binprm *bprm)
+{
+ char *p = strrchr(bprm->interp, '.');
+ struct list_head *l;
+
+ list_for_each(l, &entries) {
+ Node *e = list_entry(l, Node, list);
+ char *s;
+ int j;
+
+ if (!test_bit(Enabled, &e->flags))
+ continue;
+
+ if (!test_bit(Magic, &e->flags)) {
+ if (p && !strcmp(e->magic, p + 1))
+ return e;
+ continue;
+ }
+
+ s = bprm->buf + e->offset;
+ if (e->mask) {
+ for (j = 0; j < e->size; j++)
+ if ((*s++ ^ e->magic[j]) & e->mask[j])
+ break;
+ } else {
+ for (j = 0; j < e->size; j++)
+ if ((*s++ ^ e->magic[j]))
+ break;
+ }
+ if (j == e->size)
+ return e;
+ }
+ return NULL;
+}
+
+/*
+ * the loader itself
+ */
+static int load_misc_binary(struct linux_binprm *bprm, struct pt_regs *regs)
+{
+ Node *fmt;
+ 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)
+ goto _ret;
+
+ /* to keep locking time low, we copy the interpreter string */
+ read_lock(&entries_lock);
+ fmt = check_file(bprm);
+ if (fmt)
+ strlcpy(iname, fmt->interpreter, BINPRM_BUF_SIZE);
+ read_unlock(&entries_lock);
+ if (!fmt)
+ goto _ret;
+
+ if (!(fmt->flags & MISC_FMT_PRESERVE_ARGV0)) {
+ remove_arg_zero(bprm);
+ }
+
+ 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 (permission(bprm->file->f_dentry->d_inode, MAY_READ, NULL))
+ 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++;
+
+ /* 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 */
+
+ 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) {
+ steal_locks(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) {
+ put_files_struct(current->files);
+ current->files = files;
+ }
+ goto _ret;
+}
+
+/* Command parsers */
+
+/*
+ * parses and copies one argument enclosed in del from *sp to *dp,
+ * recognising the \x special.
+ * returns pointer to the copied argument or NULL in case of an
+ * error (and sets err) or null argument length.
+ */
+static char *scanarg(char *s, char del)
+{
+ char c;
+
+ while ((c = *s++) != del) {
+ if (c == '\\' && *s == 'x') {
+ s++;
+ if (!isxdigit(*s++))
+ return NULL;
+ if (!isxdigit(*s++))
+ return NULL;
+ }
+ }
+ return s;
+}
+
+static int unquote(char *from)
+{
+ char c = 0, *s = from, *p = from;
+
+ while ((c = *s++) != '\0') {
+ if (c == '\\' && *s == 'x') {
+ s++;
+ c = toupper(*s++);
+ *p = (c - (isdigit(c) ? '0' : 'A' - 10)) << 4;
+ c = toupper(*s++);
+ *p++ |= c - (isdigit(c) ? '0' : 'A' - 10);
+ continue;
+ }
+ *p++ = c;
+ }
+ return p - from;
+}
+
+static inline 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: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)
+{
+ Node *e;
+ int memsize, err;
+ char *buf, *p;
+ char del;
+
+ /* some sanity checks */
+ err = -EINVAL;
+ if ((count < 11) || (count > 256))
+ goto out;
+
+ err = -ENOMEM;
+ memsize = sizeof(Node) + count + 8;
+ e = (Node *) kmalloc(memsize, GFP_USER);
+ if (!e)
+ goto out;
+
+ p = buf = (char *)e + sizeof(Node);
+
+ memset(e, 0, sizeof(Node));
+ if (copy_from_user(buf, buffer, count))
+ goto Efault;
+
+ del = *p++; /* delimeter */
+
+ memset(buf+count, del, 8);
+
+ e->name = p;
+ p = strchr(p, del);
+ if (!p)
+ goto Einval;
+ *p++ = '\0';
+ if (!e->name[0] ||
+ !strcmp(e->name, ".") ||
+ !strcmp(e->name, "..") ||
+ strchr(e->name, '/'))
+ goto Einval;
+ switch (*p++) {
+ case 'E': e->flags = 1<<Enabled; break;
+ case 'M': e->flags = (1<<Enabled) | (1<<Magic); break;
+ default: goto Einval;
+ }
+ if (*p++ != del)
+ goto Einval;
+ if (test_bit(Magic, &e->flags)) {
+ char *s = strchr(p, del);
+ if (!s)
+ goto Einval;
+ *s++ = '\0';
+ e->offset = simple_strtoul(p, &p, 10);
+ if (*p++)
+ goto Einval;
+ e->magic = p;
+ p = scanarg(p, del);
+ if (!p)
+ goto Einval;
+ p[-1] = '\0';
+ if (!e->magic[0])
+ goto Einval;
+ e->mask = p;
+ p = scanarg(p, del);
+ if (!p)
+ goto Einval;
+ p[-1] = '\0';
+ if (!e->mask[0])
+ e->mask = NULL;
+ e->size = unquote(e->magic);
+ if (e->mask && unquote(e->mask) != e->size)
+ goto Einval;
+ if (e->size + e->offset > BINPRM_BUF_SIZE)
+ goto Einval;
+ } else {
+ p = strchr(p, del);
+ if (!p)
+ goto Einval;
+ *p++ = '\0';
+ e->magic = p;
+ p = strchr(p, del);
+ if (!p)
+ goto Einval;
+ *p++ = '\0';
+ if (!e->magic[0] || strchr(e->magic, '/'))
+ goto Einval;
+ p = strchr(p, del);
+ if (!p)
+ goto Einval;
+ *p++ = '\0';
+ }
+ e->interpreter = p;
+ p = strchr(p, del);
+ if (!p)
+ goto Einval;
+ *p++ = '\0';
+ if (!e->interpreter[0])
+ goto Einval;
+
+
+ p = check_special_flags (p, e);
+
+ if (*p == '\n')
+ p++;
+ if (p != buf + count)
+ goto Einval;
+ return e;
+
+out:
+ return ERR_PTR(err);
+
+Efault:
+ kfree(e);
+ return ERR_PTR(-EFAULT);
+Einval:
+ kfree(e);
+ return ERR_PTR(-EINVAL);
+}
+
+/*
+ * Set status of entry/binfmt_misc:
+ * '1' enables, '0' disables and '-1' clears entry/binfmt_misc
+ */
+static int parse_command(const char __user *buffer, size_t count)
+{
+ char s[4];
+
+ if (!count)
+ return 0;
+ if (count > 3)
+ return -EINVAL;
+ if (copy_from_user(s, buffer, count))
+ return -EFAULT;
+ if (s[count-1] == '\n')
+ count--;
+ if (count == 1 && s[0] == '0')
+ return 1;
+ if (count == 1 && s[0] == '1')
+ return 2;
+ if (count == 2 && s[0] == '-' && s[1] == '1')
+ return 3;
+ return -EINVAL;
+}
+
+/* generic stuff */
+
+static void entry_status(Node *e, char *page)
+{
+ char *dp;
+ char *status = "disabled";
+ const char * flags = "flags: ";
+
+ if (test_bit(Enabled, &e->flags))
+ status = "enabled";
+
+ if (!VERBOSE_STATUS) {
+ sprintf(page, "%s\n", status);
+ return;
+ }
+
+ 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 {
+ int i;
+
+ sprintf(dp, "offset %i\nmagic ", e->offset);
+ dp = page + strlen(page);
+ for (i = 0; i < e->size; i++) {
+ sprintf(dp, "%02x", 0xff & (int) (e->magic[i]));
+ dp += 2;
+ }
+ if (e->mask) {
+ sprintf(dp, "\nmask ");
+ dp += 6;
+ for (i = 0; i < e->size; i++) {
+ sprintf(dp, "%02x", 0xff & (int) (e->mask[i]));
+ dp += 2;
+ }
+ }
+ *dp++ = '\n';
+ *dp = '\0';
+ }
+}
+
+static struct inode *bm_get_inode(struct super_block *sb, int mode)
+{
+ struct inode * inode = new_inode(sb);
+
+ if (inode) {
+ 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_fs_time(inode->i_sb);
+ }
+ return inode;
+}
+
+static void bm_clear_inode(struct inode *inode)
+{
+ kfree(inode->u.generic_ip);
+}
+
+static void kill_node(Node *e)
+{
+ struct dentry *dentry;
+
+ write_lock(&entries_lock);
+ dentry = e->dentry;
+ if (dentry) {
+ list_del_init(&e->list);
+ e->dentry = NULL;
+ }
+ write_unlock(&entries_lock);
+
+ if (dentry) {
+ dentry->d_inode->i_nlink--;
+ d_drop(dentry);
+ dput(dentry);
+ simple_release_fs(&bm_mnt, &entry_count);
+ }
+}
+
+/* /<entry> */
+
+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;
+ loff_t pos = *ppos;
+ ssize_t res;
+ char *page;
+ int len;
+
+ if (!(page = (char*) __get_free_page(GFP_KERNEL)))
+ return -ENOMEM;
+
+ entry_status(e, page);
+ len = strlen(page);
+
+ res = -EINVAL;
+ if (pos < 0)
+ goto out;
+ res = 0;
+ if (pos >= len)
+ goto out;
+ if (len < pos + nbytes)
+ nbytes = len - pos;
+ res = -EFAULT;
+ if (copy_to_user(buf, page + pos, nbytes))
+ goto out;
+ *ppos = pos + nbytes;
+ res = nbytes;
+out:
+ free_page((unsigned long) page);
+ return res;
+}
+
+static ssize_t bm_entry_write(struct file *file, const char __user *buffer,
+ size_t count, loff_t *ppos)
+{
+ struct dentry *root;
+ Node *e = file->f_dentry->d_inode->u.generic_ip;
+ int res = parse_command(buffer, count);
+
+ switch (res) {
+ case 1: clear_bit(Enabled, &e->flags);
+ 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);
+
+ kill_node(e);
+
+ up(&root->d_inode->i_sem);
+ dput(root);
+ break;
+ default: return res;
+ }
+ return count;
+}
+
+static struct file_operations bm_entry_operations = {
+ .read = bm_entry_read,
+ .write = bm_entry_write,
+};
+
+/* /register */
+
+static ssize_t bm_register_write(struct file *file, const char __user *buffer,
+ size_t count, loff_t *ppos)
+{
+ Node *e;
+ struct inode *inode;
+ struct dentry *root, *dentry;
+ struct super_block *sb = file->f_vfsmnt->mnt_sb;
+ int err = 0;
+
+ e = create_entry(buffer, count);
+
+ if (IS_ERR(e))
+ return PTR_ERR(e);
+
+ root = dget(sb->s_root);
+ down(&root->d_inode->i_sem);
+ dentry = lookup_one_len(e->name, root, strlen(e->name));
+ err = PTR_ERR(dentry);
+ if (IS_ERR(dentry))
+ goto out;
+
+ err = -EEXIST;
+ if (dentry->d_inode)
+ goto out2;
+
+ inode = bm_get_inode(sb, S_IFREG | 0644);
+
+ err = -ENOMEM;
+ if (!inode)
+ goto out2;
+
+ err = simple_pin_fs("binfmt_misc", &bm_mnt, &entry_count);
+ if (err) {
+ iput(inode);
+ inode = NULL;
+ goto out2;
+ }
+
+ e->dentry = dget(dentry);
+ inode->u.generic_ip = e;
+ inode->i_fop = &bm_entry_operations;
+
+ d_instantiate(dentry, inode);
+ write_lock(&entries_lock);
+ list_add(&e->list, &entries);
+ write_unlock(&entries_lock);
+
+ err = 0;
+out2:
+ dput(dentry);
+out:
+ up(&root->d_inode->i_sem);
+ dput(root);
+
+ if (err) {
+ kfree(e);
+ return -EINVAL;
+ }
+ return count;
+}
+
+static struct file_operations bm_register_operations = {
+ .write = bm_register_write,
+};
+
+/* /status */
+
+static ssize_t
+bm_status_read(struct file *file, char __user *buf, size_t nbytes, loff_t *ppos)
+{
+ char *s = enabled ? "enabled" : "disabled";
+ int len = strlen(s);
+ loff_t pos = *ppos;
+
+ if (pos < 0)
+ return -EINVAL;
+ if (pos >= len)
+ return 0;
+ if (len < pos + nbytes)
+ nbytes = len - pos;
+ if (copy_to_user(buf, s + pos, nbytes))
+ return -EFAULT;
+ *ppos = pos + nbytes;
+ return nbytes;
+}
+
+static ssize_t bm_status_write(struct file * file, const char __user * buffer,
+ size_t count, loff_t *ppos)
+{
+ int res = parse_command(buffer, count);
+ struct dentry *root;
+
+ 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);
+
+ while (!list_empty(&entries))
+ kill_node(list_entry(entries.next, Node, list));
+
+ up(&root->d_inode->i_sem);
+ dput(root);
+ default: return res;
+ }
+ return count;
+}
+
+static struct file_operations bm_status_operations = {
+ .read = bm_status_read,
+ .write = bm_status_write,
+};
+
+/* Superblock handling */
+
+static struct super_operations s_ops = {
+ .statfs = simple_statfs,
+ .clear_inode = bm_clear_inode,
+};
+
+static int bm_fill_super(struct super_block * sb, void * data, int silent)
+{
+ static struct tree_descr bm_files[] = {
+ [1] = {"status", &bm_status_operations, S_IWUSR|S_IRUGO},
+ [2] = {"register", &bm_register_operations, S_IWUSR},
+ /* last one */ {""}
+ };
+ int err = simple_fill_super(sb, 0x42494e4d, bm_files);
+ if (!err)
+ sb->s_op = &s_ops;
+ return err;
+}
+
+static struct super_block *bm_get_sb(struct file_system_type *fs_type,
+ int flags, const char *dev_name, void *data)
+{
+ return get_sb_single(fs_type, flags, data, bm_fill_super);
+}
+
+static struct linux_binfmt misc_format = {
+ .module = THIS_MODULE,
+ .load_binary = load_misc_binary,
+};
+
+static struct file_system_type bm_fs_type = {
+ .owner = THIS_MODULE,
+ .name = "binfmt_misc",
+ .get_sb = bm_get_sb,
+ .kill_sb = kill_litter_super,
+};
+
+static int __init init_misc_binfmt(void)
+{
+ int err = register_filesystem(&bm_fs_type);
+ if (!err) {
+ err = register_binfmt(&misc_format);
+ if (err)
+ unregister_filesystem(&bm_fs_type);
+ }
+ return err;
+}
+
+static void __exit exit_misc_binfmt(void)
+{
+ unregister_binfmt(&misc_format);
+ unregister_filesystem(&bm_fs_type);
+}
+
+core_initcall(init_misc_binfmt);
+module_exit(exit_misc_binfmt);
+MODULE_LICENSE("GPL");