vdpa/vp_vdpa: fix kfree a wrong pointer in vp_vdpa_remove

Rong Wang · gregkh · commit 8fe12680b2c7 · 2023-01-12T12:00:34.000+01:00
[ Upstream commit ed843d6 ] In vp_vdpa_remove(), the code kfree(&vp_vdpa_mgtdev->mgtdev.id_table) uses a reference of pointer as the argument of kfree, which is the wrong pointer and then may hit crash like this: Unable to handle kernel paging request at virtual address 00ffff003363e30c Internal error: Oops: 96000004 [#1] SMP Call trace: rb_next+0x20/0x5c ext4_readdir+0x494/0x5c4 [ext4] iterate_dir+0x168/0x1b4 __se_sys_getdents64+0x68/0x170 __arm64_sys_getdents64+0x24/0x30 el0_svc_common.constprop.0+0x7c/0x1bc do_el0_svc+0x2c/0x94 el0_svc+0x20/0x30 el0_sync_handler+0xb0/0xb4 el0_sync+0x160/0x180 Code: 54000220 f9400441 b4000161 aa0103e0 (f9400821) SMP: stopping secondary CPUs Starting crashdump kernel... Fixes: ffbda8e ("vdpa/vp_vdpa : add vdpa tool support in vp_vdpa") Signed-off-by: Rong Wang <wangrong68@huawei.com> Signed-off-by: Nanyong Sun <sunnanyong@huawei.com> Message-Id: <20221207120813.2837529-1-sunnanyong@huawei.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Reviewed-by: Cindy Lu <lulu@redhat.com> Acked-by: Jason Wang <jasowang@redhat.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
diff --git a/drivers/vdpa/virtio_pci/vp_vdpa.c b/drivers/vdpa/virtio_pci/vp_vdpa.c
@@ -629,7 +629,7 @@ static void vp_vdpa_remove(struct pci_dev *pdev)
 	mdev = vp_vdpa_mgtdev->mdev;
 	vp_modern_remove(mdev);
 	vdpa_mgmtdev_unregister(&vp_vdpa_mgtdev->mgtdev);
-	kfree(&vp_vdpa_mgtdev->mgtdev.id_table);
+	kfree(vp_vdpa_mgtdev->mgtdev.id_table);
 	kfree(mdev);
 	kfree(vp_vdpa_mgtdev);
 }

Original file line number	Diff line number	Diff line change
`@@ -629,7 +629,7 @@ static void vp_vdpa_remove(struct pci_dev *pdev)`
`629`	`629`	`mdev = vp_vdpa_mgtdev->mdev;`
`630`	`630`	`vp_modern_remove(mdev);`
`631`	`631`	`vdpa_mgmtdev_unregister(&vp_vdpa_mgtdev->mgtdev);`
`632`		`- kfree(&vp_vdpa_mgtdev->mgtdev.id_table);`
	`632`	`+ kfree(vp_vdpa_mgtdev->mgtdev.id_table);`
`633`	`633`	`kfree(mdev);`
`634`	`634`	`kfree(vp_vdpa_mgtdev);`
`635`	`635`	`}`