diff options
| -rw-r--r-- | Documentation/binfmt_misc.txt | 2 | ||||
| -rw-r--r-- | fs/binfmt_misc.c | 19 |
2 files changed, 18 insertions, 3 deletions
diff --git a/Documentation/binfmt_misc.txt b/Documentation/binfmt_misc.txt index c1ed6948ba80..f64372b284e8 100644 --- a/Documentation/binfmt_misc.txt +++ b/Documentation/binfmt_misc.txt @@ -58,7 +58,7 @@ Here is what the fields mean: There are some restrictions: - - the whole register string may not exceed 255 characters + - the whole register string may not exceed 1920 characters - the magic must reside in the first 128 bytes of the file, i.e. offset+size(magic) has to be less than 128 - the interpreter string may not exceed 127 characters diff --git a/fs/binfmt_misc.c b/fs/binfmt_misc.c index b60500300dd7..c96b855d2a5e 100644 --- a/fs/binfmt_misc.c +++ b/fs/binfmt_misc.c @@ -62,7 +62,22 @@ static struct file_system_type bm_fs_type; static struct vfsmount *bm_mnt; static int entry_count; -/* +/* + * Max length of the register string. Determined by: + * - 7 delimiters + * - name: ~50 bytes + * - type: 1 byte + * - offset: 3 bytes (has to be smaller than BINPRM_BUF_SIZE) + * - magic: 128 bytes (512 in escaped form) + * - mask: 128 bytes (512 in escaped form) + * - interp: ~50 bytes + * - flags: 5 bytes + * Round that up a bit, and then back off to hold the internal data + * (like struct Node). + */ +#define MAX_REGISTER_LENGTH 1920 + +/* * Check if we support the binfmt * if we do, return the node, else NULL * locking is done in load_misc_binary @@ -279,7 +294,7 @@ static Node *create_entry(const char __user *buffer, size_t count) /* some sanity checks */ err = -EINVAL; - if ((count < 11) || (count > 256)) + if ((count < 11) || (count > MAX_REGISTER_LENGTH)) goto out; err = -ENOMEM; |