4.9-stable review patch. If anyone has any objections, please let me know.
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From: Leon Romanovsky leonro@mellanox.com
commit 6a21dfc0d0db7b7e0acedce67ca533a6eb19283c upstream.
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: 7ce86409adcd ("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 Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- drivers/infiniband/core/ucma.c | 3 +++ 1 file changed, 3 insertions(+)
--- a/drivers/infiniband/core/ucma.c +++ b/drivers/infiniband/core/ucma.c @@ -1275,6 +1275,9 @@ static ssize_t ucma_set_option(struct uc 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)) {