misc: vmw_vmci: fix kernel info-leak by initializing dbells in vmci_ctx_get_chkpt_doo...

BugLink: https://bugs.launchpad.net/bugs/1910742
commit 31dcb6c30a26d32650ce134820f27de3c675a45a upstream.

A kernel-infoleak was reported by syzbot, which was caused because
dbells was left uninitialized.
Using kzalloc() instead of kmalloc() fixes this issue.

Reported-by: syzbot+a79e17c39564bedf0930@syzkaller.appspotmail.com
Tested-by: syzbot+a79e17c39564bedf0930@syzkaller.appspotmail.com
Signed-off-by: Anant Thazhemadam <anant.thazhemadam@gmail.com>
Link: https://lore.kernel.org/r/20201122224534.333471-1-anant.thazhemadam@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Paolo Pisati <paolo.pisati@canonical.com>

diff --git a/drivers/misc/vmw_vmci/vmci_context.c b/drivers/misc/vmw_vmci/vmci_context.c
index 16695366ec926dd76d8239e288cc40b9ee408ec4..26ff49fdf0f7d3ccf95e6e803acf922c9ee2bee9 100644 (file)
--- a/drivers/misc/vmw_vmci/vmci_context.c
+++ b/drivers/misc/vmw_vmci/vmci_context.c
@@ -743,7 +743,7 @@ static int vmci_ctx_get_chkpt_doorbells(struct vmci_ctx *context,
                        return VMCI_ERROR_MORE_DATA;
                }
 
-               dbells = kmalloc(data_size, GFP_ATOMIC);
+               dbells = kzalloc(data_size, GFP_ATOMIC);
                if (!dbells)
                        return VMCI_ERROR_NO_MEM;