public inbox for linux-crypto@vger.kernel.org
 help / color / mirror / Atom feed
From: Tycho Andersen <tycho@kernel.org>
To: Tom Lendacky <thomas.lendacky@amd.com>,
	John Allen <john.allen@amd.com>,
	Herbert Xu <herbert@gondor.apana.org.au>,
	"David S. Miller" <davem@davemloft.net>,
	Ashish Kalra <ashish.kalra@amd.com>
Cc: "Borislav Petkov (AMD)" <bp@alien8.de>,
	linux-crypto@vger.kernel.org, linux-kernel@vger.kernel.org,
	Brijesh Singh <brijesh.singh@amd.com>,
	Michael Roth <michael.roth@amd.com>,
	Alexey Kardashevskiy <aik@amd.com>,
	Dan Williams <dan.j.williams@intel.com>,
	"Tycho Andersen (AMD)" <tycho@kernel.org>
Subject: [PATCH v1 4/4] crypto/ccp: Initialize data during __sev_snp_init_locked()
Date: Wed,  8 Apr 2026 08:32:59 -0600	[thread overview]
Message-ID: <20260408143259.602767-5-tycho@kernel.org> (raw)
In-Reply-To: <20260408143259.602767-1-tycho@kernel.org>

From: "Tycho Andersen (AMD)" <tycho@kernel.org>

Sashiko notes:

> is the stack variable data left uninitialized when taking the else branch?
> Since data.tio_en is later evaluated unconditionally, could stack garbage
> cause it to evaluate to true, leading to erroneous attempts to allocate
> pages and initialize SEV-TIO on unsupported hardware?

If the firmware is too old to support SEV_INIT_EX, data is left
uninitialized but used in the debug logging about whether TIO is enabled or
not.

Fixes: 4be423572da1 ("crypto/ccp: Implement SEV-TIO PCIe IDE (phase1)")
Reported-by: Sashiko
Assisted-by: Gemini:gemini-3.1-pro-preview
Link: https://sashiko.dev/#/patchset/20260324161301.1353976-1-tycho%40kernel.org
Signed-off-by: Tycho Andersen (AMD) <tycho@kernel.org>
---
 drivers/crypto/ccp/sev-dev.c | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/drivers/crypto/ccp/sev-dev.c b/drivers/crypto/ccp/sev-dev.c
index 11e2c667c0ad..7b8c1b44f2da 100644
--- a/drivers/crypto/ccp/sev-dev.c
+++ b/drivers/crypto/ccp/sev-dev.c
@@ -1356,7 +1356,7 @@ static int __sev_snp_init_locked(int *error, unsigned int max_snp_asid)
 {
 	struct sev_data_range_list *snp_range_list __free(kfree) = NULL;
 	struct psp_device *psp = psp_master;
-	struct sev_data_snp_init_ex data;
+	struct sev_data_snp_init_ex data = {};
 	struct sev_device *sev;
 	void *arg = &data;
 	int cmd, rc = 0;
@@ -1420,8 +1420,6 @@ static int __sev_snp_init_locked(int *error, unsigned int max_snp_asid)
 		 */
 		snp_add_hv_fixed_pages(sev, snp_range_list);
 
-		memset(&data, 0, sizeof(data));
-
 		if (max_snp_asid) {
 			data.ciphertext_hiding_en = 1;
 			data.max_snp_asid = max_snp_asid;
-- 
2.53.0


      parent reply	other threads:[~2026-04-08 14:34 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2026-04-08 14:32 [PATCH v1 0/4] Fix some bugs in the CCP driver Tycho Andersen
2026-04-08 14:32 ` [PATCH v1 1/4] crypto/ccp: Reverse the cleanup order in psp_dev_destroy() Tycho Andersen
2026-04-08 14:32 ` [PATCH v1 2/4] crypto/ccp: Fix snp_filter_reserved_mem_regions() off-by-one Tycho Andersen
2026-04-08 14:32 ` [PATCH v1 3/4] crypto/ccp: Check for page allocation failure correctly in TIO Tycho Andersen
2026-04-08 14:32 ` Tycho Andersen [this message]

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20260408143259.602767-5-tycho@kernel.org \
    --to=tycho@kernel.org \
    --cc=aik@amd.com \
    --cc=ashish.kalra@amd.com \
    --cc=bp@alien8.de \
    --cc=brijesh.singh@amd.com \
    --cc=dan.j.williams@intel.com \
    --cc=davem@davemloft.net \
    --cc=herbert@gondor.apana.org.au \
    --cc=john.allen@amd.com \
    --cc=linux-crypto@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=michael.roth@amd.com \
    --cc=thomas.lendacky@amd.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox