[PATCH 1/2] misc: vmw_vmci: explicitly initialize vmci_notify_bm_set_msg struct

[PATCH 1/2] misc: vmw_vmci: explicitly initialize vmci_notify_bm_set_msg struct

[Tetsuo Handa]

KMSAN complains that the vmci_use_ppn64() == false path in
vmci_dbell_register_notification_bitmap() left upper 32bits of
bitmap_set_msg.bitmap_ppn64 member uninitialized.

  =====================================================
  BUG: KMSAN: uninit-value in kmsan_check_memory+0xd/0x10
  CPU: 1 PID: 1 Comm: swapper/0 Not tainted 5.11.0-rc7+ #4
  Hardware name: VMware, Inc. VMware Virtual Platform/440BX Desktop Reference Platform, BIOS 6.00 02/27/2020
  Call Trace:
   dump_stack+0x21c/0x280
   kmsan_report+0xfb/0x1e0
   kmsan_internal_check_memory+0x484/0x520
   kmsan_check_memory+0xd/0x10
   iowrite8_rep+0x86/0x380
   vmci_send_datagram+0x150/0x280
   vmci_dbell_register_notification_bitmap+0x133/0x1e0
   vmci_guest_probe_device+0xcab/0x1e70
   pci_device_probe+0xab3/0xe70
   really_probe+0xd16/0x24d0
   driver_probe_device+0x29d/0x3a0
   device_driver_attach+0x25a/0x490
   __driver_attach+0x78c/0x840
   bus_for_each_dev+0x210/0x340
   driver_attach+0x89/0xb0
   bus_add_driver+0x677/0xc40
   driver_register+0x485/0x8e0
   __pci_register_driver+0x1ff/0x350
   vmci_guest_init+0x3e/0x41
   vmci_drv_init+0x1d6/0x43f
   do_one_initcall+0x39c/0x9a0
   do_initcall_level+0x1d7/0x259
   do_initcalls+0x127/0x1cb
   do_basic_setup+0x33/0x36
   kernel_init_freeable+0x29a/0x3ed
   kernel_init+0x1f/0x840
   ret_from_fork+0x1f/0x30

  Local variable ----bitmap_set_msg@vmci_dbell_register_notification_bitmap created at:
   vmci_dbell_register_notification_bitmap+0x50/0x1e0
   vmci_dbell_register_notification_bitmap+0x50/0x1e0

  Bytes 28-31 of 32 are uninitialized
  Memory access of size 32 starts at ffff88810098f570
  =====================================================

Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Fixes: 83e2ec765be03e8a ("VMCI: doorbell implementation.")
Cc: <stable@vger.kernel.org>
---
 drivers/misc/vmw_vmci/vmci_doorbell.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/misc/vmw_vmci/vmci_doorbell.c b/drivers/misc/vmw_vmci/vmci_doorbell.c
index 345addd9306d..fa8a7fce4481 100644
--- a/drivers/misc/vmw_vmci/vmci_doorbell.c
+++ b/drivers/misc/vmw_vmci/vmci_doorbell.c
@@ -326,7 +326,7 @@ int vmci_dbell_host_context_notify(u32 src_cid, struct vmci_handle handle)
 bool vmci_dbell_register_notification_bitmap(u64 bitmap_ppn)
 {
 	int result;
-	struct vmci_notify_bm_set_msg bitmap_set_msg;
+	struct vmci_notify_bm_set_msg bitmap_set_msg = { };
 
 	bitmap_set_msg.hdr.dst = vmci_make_handle(VMCI_HYPERVISOR_CONTEXT_ID,
 						  VMCI_SET_NOTIFY_BITMAP);
-- 
2.18.4

[PATCH 2/2] misc: vmw_vmci: explicitly initialize vmci_datagram payload

[Tetsuo Handa]

KMSAN complains that vmci_check_host_caps() left the payload part of
check_msg uninitialized.

  =====================================================
  BUG: KMSAN: uninit-value in kmsan_check_memory+0xd/0x10
  CPU: 1 PID: 1 Comm: swapper/0 Tainted: G    B             5.11.0-rc7+ #4
  Hardware name: VMware, Inc. VMware Virtual Platform/440BX Desktop Reference Platform, BIOS 6.00 02/27/2020
  Call Trace:
   dump_stack+0x21c/0x280
   kmsan_report+0xfb/0x1e0
   kmsan_internal_check_memory+0x202/0x520
   kmsan_check_memory+0xd/0x10
   iowrite8_rep+0x86/0x380
   vmci_guest_probe_device+0xf0b/0x1e70
   pci_device_probe+0xab3/0xe70
   really_probe+0xd16/0x24d0
   driver_probe_device+0x29d/0x3a0
   device_driver_attach+0x25a/0x490
   __driver_attach+0x78c/0x840
   bus_for_each_dev+0x210/0x340
   driver_attach+0x89/0xb0
   bus_add_driver+0x677/0xc40
   driver_register+0x485/0x8e0
   __pci_register_driver+0x1ff/0x350
   vmci_guest_init+0x3e/0x41
   vmci_drv_init+0x1d6/0x43f
   do_one_initcall+0x39c/0x9a0
   do_initcall_level+0x1d7/0x259
   do_initcalls+0x127/0x1cb
   do_basic_setup+0x33/0x36
   kernel_init_freeable+0x29a/0x3ed
   kernel_init+0x1f/0x840
   ret_from_fork+0x1f/0x30

  Uninit was created at:
   kmsan_internal_poison_shadow+0x5c/0xf0
   kmsan_slab_alloc+0x8d/0xe0
   kmem_cache_alloc+0x84f/0xe30
   vmci_guest_probe_device+0xd11/0x1e70
   pci_device_probe+0xab3/0xe70
   really_probe+0xd16/0x24d0
   driver_probe_device+0x29d/0x3a0
   device_driver_attach+0x25a/0x490
   __driver_attach+0x78c/0x840
   bus_for_each_dev+0x210/0x340
   driver_attach+0x89/0xb0
   bus_add_driver+0x677/0xc40
   driver_register+0x485/0x8e0
   __pci_register_driver+0x1ff/0x350
   vmci_guest_init+0x3e/0x41
   vmci_drv_init+0x1d6/0x43f
   do_one_initcall+0x39c/0x9a0
   do_initcall_level+0x1d7/0x259
   do_initcalls+0x127/0x1cb
   do_basic_setup+0x33/0x36
   kernel_init_freeable+0x29a/0x3ed
   kernel_init+0x1f/0x840
   ret_from_fork+0x1f/0x30

  Bytes 28-31 of 36 are uninitialized
  Memory access of size 36 starts at ffff8881675e5f00
  =====================================================

Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Fixes: 1f166439917b69d3 ("VMCI: guest side driver implementation.")
Cc: <stable@vger.kernel.org>
---
 drivers/misc/vmw_vmci/vmci_guest.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/misc/vmw_vmci/vmci_guest.c b/drivers/misc/vmw_vmci/vmci_guest.c
index cc8eeb361fcd..1018dc77269d 100644
--- a/drivers/misc/vmw_vmci/vmci_guest.c
+++ b/drivers/misc/vmw_vmci/vmci_guest.c
@@ -168,7 +168,7 @@ static int vmci_check_host_caps(struct pci_dev *pdev)
 				VMCI_UTIL_NUM_RESOURCES * sizeof(u32);
 	struct vmci_datagram *check_msg;
 
-	check_msg = kmalloc(msg_size, GFP_KERNEL);
+	check_msg = kzalloc(msg_size, GFP_KERNEL);
 	if (!check_msg) {
 		dev_err(&pdev->dev, "%s: Insufficient memory\n", __func__);
 		return -ENOMEM;
-- 
2.18.4