Commit 104016eb authored by Jacob Moroni's avatar Jacob Moroni Committed by Leon Romanovsky
Browse files

RDMA/umem: Fix double dma_buf_unpin in failure path 



In ib_umem_dmabuf_get_pinned_with_dma_device(), the call to
ib_umem_dmabuf_map_pages() can fail. If this occurs, the dmabuf
is immediately unpinned but the umem_dmabuf->pinned flag is still
set. Then, when ib_umem_release() is called, it calls
ib_umem_dmabuf_revoke() which will call dma_buf_unpin() again.

Fix this by removing the immediate unpin upon failure and just let
the ib_umem_release/revoke path handle it. This also ensures the
proper unmap-unpin unwind ordering if the dmabuf_map_pages call
happened to fail due to dma_resv_wait_timeout (and therefore has
a non-NULL umem_dmabuf->sgt).

Fixes: 1e4df4a2 ("RDMA/umem: Allow pinned dmabuf umem usage")
Signed-off-by: default avatarJacob Moroni <jmoroni@google.com>
Link: https://patch.msgid.link/20260224234153.1207849-1-jmoroni@google.com


Signed-off-by: default avatarLeon Romanovsky <leon@kernel.org>
parent 93a4a9b7

drivers/infiniband/core/umem_dmabuf.c

+1 −3
Original line number Diff line number Diff line
@@ -218,13 +218,11 @@ ib_umem_dmabuf_get_pinned_with_dma_device(struct ib_device *device, 


	err = ib_umem_dmabuf_map_pages(umem_dmabuf);

	if (err)

		goto err_unpin;

		goto err_release;

	dma_resv_unlock(umem_dmabuf->attach->dmabuf->resv);



	return umem_dmabuf;



err_unpin:

	dma_buf_unpin(umem_dmabuf->attach);

err_release:

	dma_resv_unlock(umem_dmabuf->attach->dmabuf->resv);

	ib_umem_release(&umem_dmabuf->umem);