From: Marcel Apfelbaum <[email protected]> Ensure mremap boundaries not trusting the guest kernel to pass the correct buffer length.
Fixes: CVE-2021-3582 Reported-by: VictorV (Kunlun Lab) <[email protected]> Tested-by: VictorV (Kunlun Lab) <[email protected]> Signed-off-by: Marcel Apfelbaum <[email protected]> Message-Id: <[email protected]> Reviewed-by: Yuval Shaia <[email protected]> Tested-by: Yuval Shaia <[email protected]> Reviewed-by: Prasad J Pandit <[email protected]> Signed-off-by: Marcel Apfelbaum <[email protected]> (cherry picked from commit 284f191b4abad213aed04cb0458e1600fd18d7c4) Signed-off-by: Michael Roth <[email protected]> --- hw/rdma/vmw/pvrdma_cmd.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/hw/rdma/vmw/pvrdma_cmd.c b/hw/rdma/vmw/pvrdma_cmd.c index f59879e257..da7ddfa548 100644 --- a/hw/rdma/vmw/pvrdma_cmd.c +++ b/hw/rdma/vmw/pvrdma_cmd.c @@ -38,6 +38,13 @@ static void *pvrdma_map_to_pdir(PCIDevice *pdev, uint64_t pdir_dma, return NULL; } + length = ROUND_UP(length, TARGET_PAGE_SIZE); + if (nchunks * TARGET_PAGE_SIZE != length) { + rdma_error_report("Invalid nchunks/length (%u, %lu)", nchunks, + (unsigned long)length); + return NULL; + } + dir = rdma_pci_dma_map(pdev, pdir_dma, TARGET_PAGE_SIZE); if (!dir) { rdma_error_report("Failed to map to page directory"); -- 2.25.1
