linux-kernel - [PATCH v13 04/26] KVM: guest_memfd: Fix PTR_ERR() handling in __kvm_gmem_get

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20240418194133.1452059-5-michael.roth@amd.com>
Date: Thu, 18 Apr 2024 14:41:11 -0500
From: Michael Roth <michael.roth@....com>
To: <kvm@...r.kernel.org>
CC: <linux-coco@...ts.linux.dev>, <linux-mm@...ck.org>,
	<linux-crypto@...r.kernel.org>, <x86@...nel.org>,
	<linux-kernel@...r.kernel.org>, <tglx@...utronix.de>, <mingo@...hat.com>,
	<jroedel@...e.de>, <thomas.lendacky@....com>, <hpa@...or.com>,
	<ardb@...nel.org>, <pbonzini@...hat.com>, <seanjc@...gle.com>,
	<vkuznets@...hat.com>, <jmattson@...gle.com>, <luto@...nel.org>,
	<dave.hansen@...ux.intel.com>, <slp@...hat.com>, <pgonda@...gle.com>,
	<peterz@...radead.org>, <srinivas.pandruvada@...ux.intel.com>,
	<rientjes@...gle.com>, <dovmurik@...ux.ibm.com>, <tobin@....com>,
	<bp@...en8.de>, <vbabka@...e.cz>, <kirill@...temov.name>,
	<ak@...ux.intel.com>, <tony.luck@...el.com>,
	<sathyanarayanan.kuppuswamy@...ux.intel.com>, <alpergun@...gle.com>,
	<jarkko@...nel.org>, <ashish.kalra@....com>, <nikunj.dadhania@....com>,
	<pankaj.gupta@....com>, <liam.merwick@...cle.com>
Subject: [PATCH v13 04/26] KVM: guest_memfd: Fix PTR_ERR() handling in __kvm_gmem_get_pfn()

kvm_gmem_get_folio() may return a PTR_ERR() rather than just NULL. In
particular, for cases where EEXISTS is returned when FGP_CREAT_ONLY
flag is used. Handle this properly in __kvm_gmem_get_pfn().

Signed-off-by: Michael Roth <michael.roth@....com>
---
 virt/kvm/guest_memfd.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/virt/kvm/guest_memfd.c b/virt/kvm/guest_memfd.c
index ccf22e44f387..9d7c6a70c547 100644
--- a/virt/kvm/guest_memfd.c
+++ b/virt/kvm/guest_memfd.c
@@ -580,8 +580,8 @@ static int __kvm_gmem_get_pfn(struct file *file, struct kvm_memory_slot *slot,
 	}
 
 	folio = kvm_gmem_get_folio(file_inode(file), index, prepare);
-	if (!folio)
-		return -ENOMEM;
+	if (IS_ERR_OR_NULL(folio))
+		return folio ? PTR_ERR(folio) : -ENOMEM;
 
 	if (folio_test_hwpoison(folio)) {
 		r = -EHWPOISON;
-- 
2.25.1