From bc0fd67feba2e0770aad85393500ba77c6489f1c Mon Sep 17 00:00:00 2001 From: Milan Broz Date: Mon, 16 Mar 2009 16:56:01 +0000 Subject: [PATCH] dm ioctl: validate name length when renaming When renaming a mapped device validate the length of the new name. The rename ioctl accepted any correctly-terminated string enclosed within the data passed from userspace. The other ioctls enforce a size limit of DM_NAME_LEN. If the name is changed and becomes longer than that, the device can no longer be addressed by name. Fix it by properly checking for device name length (including terminating zero). Cc: stable@kernel.org Signed-off-by: Milan Broz Reviewed-by: Jonathan Brassow Reviewed-by: Alasdair G Kergon Signed-off-by: Alasdair G Kergon --- drivers/md/dm-ioctl.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/md/dm-ioctl.c b/drivers/md/dm-ioctl.c index 54d0588fc1f6..977f36612e83 100644 --- a/drivers/md/dm-ioctl.c +++ b/drivers/md/dm-ioctl.c @@ -704,7 +704,8 @@ static int dev_rename(struct dm_ioctl *param, size_t param_size) char *new_name = (char *) param + param->data_start; if (new_name < param->data || - invalid_str(new_name, (void *) param + param_size)) { + invalid_str(new_name, (void *) param + param_size) || + strlen(new_name) > DM_NAME_LEN - 1) { DMWARN("Invalid new logical volume name supplied."); return -EINVAL; }