From: Leon Romanovsky <leonro@xxxxxxxxxxxx> 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@xxxxxxxxxxxxxxxxxxxxxxxxx Fixes: 7ce86409adcd ("RDMA/ucma: Allow user space to set service type") Signed-off-by: Leon Romanovsky <leonro@xxxxxxxxxxxx> --- drivers/infiniband/core/ucma.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/infiniband/core/ucma.c b/drivers/infiniband/core/ucma.c index f015f1bf88c9..1817dfea8345 100644 --- a/drivers/infiniband/core/ucma.c +++ b/drivers/infiniband/core/ucma.c @@ -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)) { -- 2.16.2 -- To unsubscribe from this list: send the line "unsubscribe linux-rdma" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html