RDMA/ucma: Limit possible option size

Users of ucma are supposed to provide size of option level,
in most paths it is supposed to be equal to u8 or u16, but
it is not the case for the IB path record, where it can be
multiple of struct ib_path_rec_data.

This patch takes simplest possible approach and prevents providing
values more than possible to allocate.

Reported-by: syzbot+a38b0e9f694c379ca7ce@syzkaller.appspotmail.com
Fixes: 7ce86409ad ("RDMA/ucma: Allow user space to set service type")
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
This commit is contained in:
Leon Romanovsky 2018-03-07 14:49:09 +02:00 committed by Doug Ledford
parent bb7f8f199c
commit 6a21dfc0d0
1 changed files with 3 additions and 0 deletions

View File

@ -1294,6 +1294,9 @@ static ssize_t ucma_set_option(struct ucma_file *file, const char __user *inbuf,
if (IS_ERR(ctx))
return PTR_ERR(ctx);
if (unlikely(cmd.optval > KMALLOC_MAX_SIZE))
return -EINVAL;
optval = memdup_user((void __user *) (unsigned long) cmd.optval,
cmd.optlen);
if (IS_ERR(optval)) {