On 4/7/23 15:39, Avihai Horon wrote:
vfio_realize() has the following flow: 1. vfio_bars_prepare() -- sets VFIOBAR->size. 2. msix_early_setup(). 3. vfio_bars_register() -- allocates VFIOBAR->mr.After vfio_bars_prepare() is called msix_early_setup() can fail. If it does fail, vfio_bars_register() is never called and VFIOBAR->mr is not allocated. In this case, vfio_bars_finalize() is called as part of the error flow to free the bars' resources. However, vfio_bars_finalize() calls object_unparent() for VFIOBAR->mr after checking only VFIOBAR->size, and thus we get a null pointer dereference. Fix it by checking VFIOBAR->mr in vfio_bars_finalize(). Fixes: 89d5202edc50 ("vfio/pci: Allow relocating MSI-X MMIO") Signed-off-by: Avihai Horon <avih...@nvidia.com> --- Changes from v1: * Assert VFIOBAR->size and set VFIOBAR->mr to NULL to make the code more accurate. (Philippe) * Small reword in the last paragraph of the commit message. hw/vfio/pci.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-)
Reviewed-by: Philippe Mathieu-Daudé <phi...@linaro.org>
