This is a note to let you know that I've just added the patch titled VMCI: check context->notify_page after call to get_user_pages_fast() to avoid GPF to the 6.2-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: vmci-check-context-notify_page-after-call-to-get_use.patch and it can be found in the queue-6.2 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit e38aa513d7c08dca74d623de5f50a44076d36853 Author: George Kennedy <george.kennedy@xxxxxxxxxx> Date: Mon Nov 28 15:18:25 2022 -0500 VMCI: check context->notify_page after call to get_user_pages_fast() to avoid GPF [ Upstream commit 1a726cb47fd204109c767409fa9ca15a96328f14 ] The call to get_user_pages_fast() in vmci_host_setup_notify() can return NULL context->notify_page causing a GPF. To avoid GPF check if context->notify_page == NULL and return error if so. general protection fault, probably for non-canonical address 0xe0009d1000000060: 0000 [#1] PREEMPT SMP KASAN NOPTI KASAN: maybe wild-memory-access in range [0x0005088000000300- 0x0005088000000307] CPU: 2 PID: 26180 Comm: repro_34802241 Not tainted 6.1.0-rc4 #1 Hardware name: Red Hat KVM, BIOS 1.15.0-2.module+el8.6.0 04/01/2014 RIP: 0010:vmci_ctx_check_signal_notify+0x91/0xe0 Call Trace: <TASK> vmci_host_unlocked_ioctl+0x362/0x1f40 __x64_sys_ioctl+0x1a1/0x230 do_syscall_64+0x3a/0x90 entry_SYSCALL_64_after_hwframe+0x63/0xcd Fixes: a1d88436d53a ("VMCI: Fix two UVA mapping bugs") Reported-by: syzkaller <syzkaller@xxxxxxxxxxxxxxxx> Signed-off-by: George Kennedy <george.kennedy@xxxxxxxxxx> Reviewed-by: Vishnu Dasa <vdasa@xxxxxxxxxx> Link: https://lore.kernel.org/r/1669666705-24012-1-git-send-email-george.kennedy@xxxxxxxxxx Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/drivers/misc/vmw_vmci/vmci_host.c b/drivers/misc/vmw_vmci/vmci_host.c index da1e2a773823e..857b9851402a6 100644 --- a/drivers/misc/vmw_vmci/vmci_host.c +++ b/drivers/misc/vmw_vmci/vmci_host.c @@ -242,6 +242,8 @@ static int vmci_host_setup_notify(struct vmci_ctx *context, context->notify_page = NULL; return VMCI_ERROR_GENERIC; } + if (context->notify_page == NULL) + return VMCI_ERROR_UNAVAILABLE; /* * Map the locked page and set up notify pointer.