From 91dfd98216d817ec5f1c55890bacb7b4fe9b068a Mon Sep 17 00:00:00 2001 From: David Rientjes Date: Fri, 30 Dec 2022 14:18:46 -0800 Subject: crypto: ccp - Avoid page allocation failure warning for SEV_GET_ID2 For SEV_GET_ID2, the user provided length does not have a specified limitation because the length of the ID may change in the future. The kernel memory allocation, however, is implicitly limited to 4MB on x86 by the page allocator, otherwise the kzalloc() will fail. When this happens, it is best not to spam the kernel log with the warning. Simply fail the allocation and return ENOMEM to the user. Fixes: d6112ea0cb34 ("crypto: ccp - introduce SEV_GET_ID2 command") Reported-by: Andy Nguyen Reported-by: Peter Gonda Suggested-by: Herbert Xu Signed-off-by: David Rientjes Acked-by: Tom Lendacky Signed-off-by: Herbert Xu --- drivers/crypto/ccp/sev-dev.c | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) (limited to 'drivers/crypto/ccp') diff --git a/drivers/crypto/ccp/sev-dev.c b/drivers/crypto/ccp/sev-dev.c index 06fc7156c04f..56998bc579d6 100644 --- a/drivers/crypto/ccp/sev-dev.c +++ b/drivers/crypto/ccp/sev-dev.c @@ -881,7 +881,14 @@ static int sev_ioctl_do_get_id2(struct sev_issue_cmd *argp) input_address = (void __user *)input.address; if (input.address && input.length) { - id_blob = kzalloc(input.length, GFP_KERNEL); + /* + * The length of the ID shouldn't be assumed by software since + * it may change in the future. The allocation size is limited + * to 1 << (PAGE_SHIFT + MAX_ORDER - 1) by the page allocator. + * If the allocation fails, simply return ENOMEM rather than + * warning in the kernel log. + */ + id_blob = kzalloc(input.length, GFP_KERNEL | __GFP_NOWARN); if (!id_blob) return -ENOMEM; -- cgit