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]
Date:   Wed, 25 Jan 2023 00:38:49 -0800
From:   Suren Baghdasaryan <surenb@...gle.com>
To:     akpm@...ux-foundation.org
Cc:     michel@...pinasse.org, jglisse@...gle.com, mhocko@...e.com,
        vbabka@...e.cz, hannes@...xchg.org, mgorman@...hsingularity.net,
        dave@...olabs.net, willy@...radead.org, liam.howlett@...cle.com,
        peterz@...radead.org, ldufour@...ux.ibm.com, paulmck@...nel.org,
        luto@...nel.org, songliubraving@...com, peterx@...hat.com,
        david@...hat.com, dhowells@...hat.com, hughd@...gle.com,
        bigeasy@...utronix.de, kent.overstreet@...ux.dev,
        punit.agrawal@...edance.com, lstoakes@...il.com,
        peterjung1337@...il.com, rientjes@...gle.com,
        axelrasmussen@...gle.com, joelaf@...gle.com, minchan@...gle.com,
        jannh@...gle.com, shakeelb@...gle.com, tatashin@...gle.com,
        edumazet@...gle.com, gthelen@...gle.com, gurua@...gle.com,
        arjunroy@...gle.com, soheil@...gle.com, hughlynch@...gle.com,
        leewalsh@...gle.com, posk@...gle.com, will@...nel.org,
        aneesh.kumar@...ux.ibm.com, npiggin@...il.com,
        chenhuacai@...nel.org, tglx@...utronix.de, mingo@...hat.com,
        bp@...en8.de, dave.hansen@...ux.intel.com, richard@....at,
        anton.ivanov@...bridgegreys.com, johannes@...solutions.net,
        qianweili@...wei.com, wangzhou1@...ilicon.com,
        herbert@...dor.apana.org.au, davem@...emloft.net, vkoul@...nel.org,
        airlied@...il.com, daniel@...ll.ch,
        maarten.lankhorst@...ux.intel.com, mripard@...nel.org,
        tzimmermann@...e.de, l.stach@...gutronix.de,
        krzysztof.kozlowski@...aro.org, patrik.r.jakobsson@...il.com,
        matthias.bgg@...il.com, robdclark@...il.com,
        quic_abhinavk@...cinc.com, dmitry.baryshkov@...aro.org,
        tomba@...nel.org, hjc@...k-chips.com, heiko@...ech.de,
        ray.huang@....com, kraxel@...hat.com, sre@...nel.org,
        mcoquelin.stm32@...il.com, alexandre.torgue@...s.st.com,
        tfiga@...omium.org, m.szyprowski@...sung.com, mchehab@...nel.org,
        dimitri.sivanich@....com, zhangfei.gao@...aro.org,
        jejb@...ux.ibm.com, martin.petersen@...cle.com,
        dgilbert@...erlog.com, hdegoede@...hat.com, mst@...hat.com,
        jasowang@...hat.com, alex.williamson@...hat.com, deller@....de,
        jayalk@...works.biz, viro@...iv.linux.org.uk, nico@...xnic.net,
        xiang@...nel.org, chao@...nel.org, tytso@....edu,
        adilger.kernel@...ger.ca, miklos@...redi.hu,
        mike.kravetz@...cle.com, muchun.song@...ux.dev, bhe@...hat.com,
        andrii@...nel.org, yoshfuji@...ux-ipv6.org, dsahern@...nel.org,
        kuba@...nel.org, pabeni@...hat.com, perex@...ex.cz, tiwai@...e.com,
        haojian.zhuang@...il.com, robert.jarzmik@...e.fr,
        linux-mm@...ck.org, linux-arm-kernel@...ts.infradead.org,
        linuxppc-dev@...ts.ozlabs.org, x86@...nel.org,
        linux-kernel@...r.kernel.org, linux-graphics-maintainer@...are.com,
        linux-ia64@...r.kernel.org, linux-arch@...r.kernel.org,
        loongarch@...ts.linux.dev, kvm@...r.kernel.org,
        linux-s390@...r.kernel.org, linux-sgx@...r.kernel.org,
        linux-um@...ts.infradead.org, linux-acpi@...r.kernel.org,
        linux-crypto@...r.kernel.org, nvdimm@...ts.linux.dev,
        dmaengine@...r.kernel.org, amd-gfx@...ts.freedesktop.org,
        dri-devel@...ts.freedesktop.org, etnaviv@...ts.freedesktop.org,
        linux-samsung-soc@...r.kernel.org, intel-gfx@...ts.freedesktop.org,
        linux-mediatek@...ts.infradead.org, linux-arm-msm@...r.kernel.org,
        freedreno@...ts.freedesktop.org,
        linux-rockchip@...ts.infradead.org, linux-tegra@...r.kernel.org,
        virtualization@...ts.linux-foundation.org,
        xen-devel@...ts.xenproject.org,
        linux-stm32@...md-mailman.stormreply.com,
        linux-rdma@...r.kernel.org, linux-media@...r.kernel.org,
        linux-accelerators@...ts.ozlabs.org, sparclinux@...r.kernel.org,
        linux-scsi@...r.kernel.org, linux-staging@...ts.linux.dev,
        target-devel@...r.kernel.org, linux-usb@...r.kernel.org,
        netdev@...r.kernel.org, linux-fbdev@...r.kernel.org,
        linux-aio@...ck.org, linux-fsdevel@...r.kernel.org,
        linux-erofs@...ts.ozlabs.org, linux-ext4@...r.kernel.org,
        devel@...ts.orangefs.org, kexec@...ts.infradead.org,
        linux-xfs@...r.kernel.org, bpf@...r.kernel.org,
        linux-perf-users@...r.kernel.org, kasan-dev@...glegroups.com,
        selinux@...r.kernel.org, alsa-devel@...a-project.org,
        kernel-team@...roid.com, surenb@...gle.com
Subject: [PATCH v2 4/6] mm: replace vma->vm_flags indirect modification in ksm_madvise

Replace indirect modifications to vma->vm_flags with calls to modifier
functions to be able to track flag changes and to keep vma locking
correctness. Add a BUG_ON check in ksm_madvise() to catch indirect
vm_flags modification attempts.

Signed-off-by: Suren Baghdasaryan <surenb@...gle.com>
---
 arch/powerpc/kvm/book3s_hv_uvmem.c | 5 ++++-
 arch/s390/mm/gmap.c                | 5 ++++-
 mm/khugepaged.c                    | 2 ++
 mm/ksm.c                           | 2 ++
 4 files changed, 12 insertions(+), 2 deletions(-)

diff --git a/arch/powerpc/kvm/book3s_hv_uvmem.c b/arch/powerpc/kvm/book3s_hv_uvmem.c
index 1d67baa5557a..325a7a47d348 100644
--- a/arch/powerpc/kvm/book3s_hv_uvmem.c
+++ b/arch/powerpc/kvm/book3s_hv_uvmem.c
@@ -393,6 +393,7 @@ static int kvmppc_memslot_page_merge(struct kvm *kvm,
 {
 	unsigned long gfn = memslot->base_gfn;
 	unsigned long end, start = gfn_to_hva(kvm, gfn);
+	unsigned long vm_flags;
 	int ret = 0;
 	struct vm_area_struct *vma;
 	int merge_flag = (merge) ? MADV_MERGEABLE : MADV_UNMERGEABLE;
@@ -409,12 +410,14 @@ static int kvmppc_memslot_page_merge(struct kvm *kvm,
 			ret = H_STATE;
 			break;
 		}
+		vm_flags = vma->vm_flags;
 		ret = ksm_madvise(vma, vma->vm_start, vma->vm_end,
-			  merge_flag, &vma->vm_flags);
+			  merge_flag, &vm_flags);
 		if (ret) {
 			ret = H_STATE;
 			break;
 		}
+		reset_vm_flags(vma, vm_flags);
 		start = vma->vm_end;
 	} while (end > vma->vm_end);
 
diff --git a/arch/s390/mm/gmap.c b/arch/s390/mm/gmap.c
index 3a695b8a1e3c..d5eb47dcdacb 100644
--- a/arch/s390/mm/gmap.c
+++ b/arch/s390/mm/gmap.c
@@ -2587,14 +2587,17 @@ int gmap_mark_unmergeable(void)
 {
 	struct mm_struct *mm = current->mm;
 	struct vm_area_struct *vma;
+	unsigned long vm_flags;
 	int ret;
 	VMA_ITERATOR(vmi, mm, 0);
 
 	for_each_vma(vmi, vma) {
+		vm_flags = vma->vm_flags;
 		ret = ksm_madvise(vma, vma->vm_start, vma->vm_end,
-				  MADV_UNMERGEABLE, &vma->vm_flags);
+				  MADV_UNMERGEABLE, &vm_flags);
 		if (ret)
 			return ret;
+		reset_vm_flags(vma, vm_flags);
 	}
 	mm->def_flags &= ~VM_MERGEABLE;
 	return 0;
diff --git a/mm/khugepaged.c b/mm/khugepaged.c
index 8abc59345bf2..76b24cd0c179 100644
--- a/mm/khugepaged.c
+++ b/mm/khugepaged.c
@@ -354,6 +354,8 @@ struct attribute_group khugepaged_attr_group = {
 int hugepage_madvise(struct vm_area_struct *vma,
 		     unsigned long *vm_flags, int advice)
 {
+	/* vma->vm_flags can be changed only using modifier functions */
+	BUG_ON(vm_flags == &vma->vm_flags);
 	switch (advice) {
 	case MADV_HUGEPAGE:
 #ifdef CONFIG_S390
diff --git a/mm/ksm.c b/mm/ksm.c
index 04f1c8c2df11..992b2be9f5e6 100644
--- a/mm/ksm.c
+++ b/mm/ksm.c
@@ -2573,6 +2573,8 @@ int ksm_madvise(struct vm_area_struct *vma, unsigned long start,
 	struct mm_struct *mm = vma->vm_mm;
 	int err;
 
+	/* vma->vm_flags can be changed only using modifier functions */
+	BUG_ON(vm_flags == &vma->vm_flags);
 	switch (advice) {
 	case MADV_MERGEABLE:
 		/*
-- 
2.39.1

Powered by blists - more mailing lists

Powered by Openwall GNU/*/Linux Powered by OpenVZ