This is a note to let you know that I've just added the patch titled misc: vmw_vmci: explicitly initialize vmci_datagram payload to the 5.12-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: misc-vmw_vmci-explicitly-initialize-vmci_datagram-payload.patch and it can be found in the queue-5.12 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From b2192cfeba8481224da0a4ec3b4a7ccd80b1623b Mon Sep 17 00:00:00 2001 From: Tetsuo Handa <penguin-kernel@xxxxxxxxxxxxxxxxxxx> Date: Fri, 2 Apr 2021 21:17:42 +0900 Subject: misc: vmw_vmci: explicitly initialize vmci_datagram payload From: Tetsuo Handa <penguin-kernel@xxxxxxxxxxxxxxxxxxx> commit b2192cfeba8481224da0a4ec3b4a7ccd80b1623b upstream. 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 ===================================================== Fixes: 1f166439917b69d3 ("VMCI: guest side driver implementation.") Cc: <stable@xxxxxxxxxxxxxxx> Signed-off-by: Tetsuo Handa <penguin-kernel@xxxxxxxxxxxxxxxxxxx> Link: https://lore.kernel.org/r/20210402121742.3917-2-penguin-kernel@xxxxxxxxxxxxxxxxxxx Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/misc/vmw_vmci/vmci_guest.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- 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 p 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; Patches currently in stable-queue which might be from penguin-kernel@xxxxxxxxxxxxxxxxxxx are queue-5.12/misc-vmw_vmci-explicitly-initialize-vmci_datagram-payload.patch queue-5.12/misc-vmw_vmci-explicitly-initialize-vmci_notify_bm_set_msg-struct.patch