diff options
Diffstat (limited to 'fs/binfmt_misc.c')
| -rw-r--r-- | fs/binfmt_misc.c | 23 |
1 files changed, 19 insertions, 4 deletions
diff --git a/fs/binfmt_misc.c b/fs/binfmt_misc.c index b60500300dd7..fd8beb9657a2 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; @@ -396,12 +411,12 @@ 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 (!count) + return 0; if (s[count-1] == '\n') count--; if (count == 1 && s[0] == '0') |