From patchwork Mon Sep 2 19:08:13 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Mark Brown X-Patchwork-Id: 13787653 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 7D75A1547DB; Mon, 2 Sep 2024 19:08:53 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1725304133; cv=none; b=e6mX4OKohc2Mb8PkrFAxxiVSVFJutUloUFL4BRzLQ2fk6npdJAeK0GC47O2Ihm5+yCQXnu1iYobD2mQ4pAA+dcaLeOJgWd+lQzskNwFQOejj+2i9DlXJ2oyXb8zLYeEtaAXby0Xsk6AajNmqy7gNnL5WE66K5dutHIACKUKgxSs= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1725304133; c=relaxed/simple; bh=1mgs6QxxhFvlJ6QWlI5cwMYNjmTctMPvXSWGRMOjy+c=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=sUqU2RvEcTOwmvfxQwV+7u2Loafh0msCre3M9lguXdPQyQldEEnWGB/btvI4kxnqJ7bYflax5GRVUpyaKQJqwMFjTDa5cO/G9/axaawHwTQvPoXlRejQeJsVw2Hv9ueAkYyylarMk2IqX4/qpzYIzg/NiQ+5lvh9855uG6OfR0c= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=A6qq5Hap; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="A6qq5Hap" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 3E433C4CEC8; Mon, 2 Sep 2024 19:08:43 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1725304133; bh=1mgs6QxxhFvlJ6QWlI5cwMYNjmTctMPvXSWGRMOjy+c=; h=From:Date:Subject:References:In-Reply-To:To:Cc:From; b=A6qq5HapfAAfo13+J7ISO2ZSoyZqyROu2OxBiS36+p9qOcpNrbMfrEV1SITf+Ftme hEktVwtsNDUkq0N9qLEwaTUTQn/iDu3j2PwS/bjXej3x7V5Ht+hdrEL4aF1WixXrNq RjZCeyG8g2x0YiUGhXxQx5i69StPgmx9EFNkpIDlNOksGT8Z9hJYHUtl3AC21v8D9h WiEAyR8JJgoQw+cOI8s8ELbUMtMRKmThy9NRNrvHPjLtr/+S/SwgQKuDgcfBOO0uB9 S7vI2lZADCyUxFyaMnrO1JH5PmhUTW5x49bKniRxPBL5z7vkTlaRWunP8m7TszhqLw PDyrVfbG7dEnw== From: Mark Brown Date: Mon, 02 Sep 2024 20:08:13 +0100 Subject: [PATCH 1/3] mm: Make arch_get_unmapped_area() take vm_flags by default Precedence: bulk X-Mailing-List: linux-sh@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Message-Id: <20240902-mm-generic-shadow-stack-guard-v1-1-9acda38b3dd3@kernel.org> References: <20240902-mm-generic-shadow-stack-guard-v1-0-9acda38b3dd3@kernel.org> In-Reply-To: <20240902-mm-generic-shadow-stack-guard-v1-0-9acda38b3dd3@kernel.org> To: Richard Henderson , Ivan Kokshaysky , Matt Turner , Vineet Gupta , Russell King , Guo Ren , Huacai Chen , WANG Xuerui , "James E.J. Bottomley" , Helge Deller , Michael Ellerman , Nicholas Piggin , Christophe Leroy , Naveen N Rao , Alexander Gordeev , Gerald Schaefer , Heiko Carstens , Vasily Gorbik , Christian Borntraeger , Sven Schnelle , Yoshinori Sato , Rich Felker , John Paul Adrian Glaubitz , "David S. Miller" , Andreas Larsson , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , x86@kernel.org, "H. Peter Anvin" , Chris Zankel , Max Filippov , Andrew Morton , "Liam R. Howlett" , Vlastimil Babka , Lorenzo Stoakes Cc: Catalin Marinas , Will Deacon , Deepak Gupta , linux-arm-kernel@lists.infradead.org, linux-alpha@vger.kernel.org, linux-kernel@vger.kernel.org, linux-snps-arc@lists.infradead.org, linux-arm-kernel@lists.infradead.org, linux-csky@vger.kernel.org, loongarch@lists.linux.dev, linux-parisc@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-s390@vger.kernel.org, linux-sh@vger.kernel.org, sparclinux@vger.kernel.org, linux-mm@kvack.org, Mark Brown X-Mailer: b4 0.15-dev-37811 X-Developer-Signature: v=1; a=openpgp-sha256; l=19220; i=broonie@kernel.org; h=from:subject:message-id; bh=1mgs6QxxhFvlJ6QWlI5cwMYNjmTctMPvXSWGRMOjy+c=; b=owEBbQGS/pANAwAKASTWi3JdVIfQAcsmYgBm1g0uGCggx4QH7/NGiOcYyMzP2fdwWZK3xJbL39HP SyoBNEeJATMEAAEKAB0WIQSt5miqZ1cYtZ/in+ok1otyXVSH0AUCZtYNLgAKCRAk1otyXVSH0JDkB/ 9oGP9EsZAu2ng1irDsPdXdmWBYVkTKZe/H2vGo+b5GTRhsdc60GgJ8ruwJhRRyx9dxewJ4FU2g6uU/ tm0glfDEqVTb3b2rwymDTVa13yLLB80gpaqAeB6AgKbxmSU/ePQ6ZFm4dln+ESpofRhJoIeWGbaExW 0tKajWONyvnx9s0vv9wT7doL9oUj+i0Py79mA8nTeiu/v65J7taLiv+7l/7+zXBAhf6qBfCDe2Ilb6 o9KzpHhJSa/qVKLwh8jcSNY8khXfZgFVG0qnoq9MpKuadFS/6axRitDBUSpRjRBBv0iUQjeqet6CK1 3LeeF1ff+ls4ttcmtvGTsEKdCz/tMW X-Developer-Key: i=broonie@kernel.org; a=openpgp; fpr=3F2568AAC26998F9E813A1C5C3F436CA30F5D8EB When we introduced arch_get_unmapped_area_vmflags() in 961148704acd ("mm: introduce arch_get_unmapped_area_vmflags()") we did so as part of properly supporting guard pages for shadow stacks on x86_64, which uses a custom arch_get_unmapped_area(). Equivalent features are also present on both arm64 and RISC-V, both of which use the generic implementation of arch_get_unmapped_area() and will require equivalent modification there. Rather than continue to deal with having two versions of the functions let's bite the bullet and have all implementations of arch_get_unmapped_area() take vm_flags as a parameter. The new parameter is currently ignored by all implementations other than x86. The only caller that doesn't have a vm_flags available is mm_get_unmapped_area(), as for the x86 implementation and the wrapper used on other architectures this is modified to supply no flags. No functional changes. Signed-off-by: Mark Brown Acked-by: Lorenzo Stoakes (for mm/mmap.c part) Reviewed-by: Liam R. Howlett Acked-by: Helge Deller # parisc --- arch/alpha/kernel/osf_sys.c | 2 +- arch/arc/mm/mmap.c | 3 ++- arch/arm/mm/mmap.c | 7 ++++--- arch/csky/abiv1/mmap.c | 3 ++- arch/loongarch/mm/mmap.c | 5 +++-- arch/mips/mm/mmap.c | 2 +- arch/parisc/kernel/sys_parisc.c | 5 +++-- arch/parisc/mm/hugetlbpage.c | 2 +- arch/powerpc/mm/book3s64/slice.c | 6 ++++-- arch/s390/mm/mmap.c | 4 ++-- arch/sh/mm/mmap.c | 5 +++-- arch/sparc/kernel/sys_sparc_32.c | 2 +- arch/sparc/kernel/sys_sparc_64.c | 4 ++-- arch/x86/include/asm/pgtable_64.h | 1 - arch/x86/kernel/sys_x86_64.c | 21 +++------------------ arch/xtensa/kernel/syscall.c | 3 ++- include/linux/sched/mm.h | 23 ++++++++--------------- mm/mmap.c | 31 +++++++------------------------ 18 files changed, 49 insertions(+), 80 deletions(-) diff --git a/arch/alpha/kernel/osf_sys.c b/arch/alpha/kernel/osf_sys.c index e5f881bc8288..8886ab539273 100644 --- a/arch/alpha/kernel/osf_sys.c +++ b/arch/alpha/kernel/osf_sys.c @@ -1229,7 +1229,7 @@ arch_get_unmapped_area_1(unsigned long addr, unsigned long len, unsigned long arch_get_unmapped_area(struct file *filp, unsigned long addr, unsigned long len, unsigned long pgoff, - unsigned long flags) + unsigned long flags, vm_flags_t vm_flags) { unsigned long limit; diff --git a/arch/arc/mm/mmap.c b/arch/arc/mm/mmap.c index 69a915297155..2185afe8d59f 100644 --- a/arch/arc/mm/mmap.c +++ b/arch/arc/mm/mmap.c @@ -23,7 +23,8 @@ */ unsigned long arch_get_unmapped_area(struct file *filp, unsigned long addr, - unsigned long len, unsigned long pgoff, unsigned long flags) + unsigned long len, unsigned long pgoff, + unsigned long flags, vm_flags_t vm_flags) { struct mm_struct *mm = current->mm; struct vm_area_struct *vma; diff --git a/arch/arm/mm/mmap.c b/arch/arm/mm/mmap.c index d65d0e6ed10a..3dbb383c26d5 100644 --- a/arch/arm/mm/mmap.c +++ b/arch/arm/mm/mmap.c @@ -28,7 +28,8 @@ */ unsigned long arch_get_unmapped_area(struct file *filp, unsigned long addr, - unsigned long len, unsigned long pgoff, unsigned long flags) + unsigned long len, unsigned long pgoff, + unsigned long flags, vm_flags_t vm_flags) { struct mm_struct *mm = current->mm; struct vm_area_struct *vma; @@ -78,8 +79,8 @@ arch_get_unmapped_area(struct file *filp, unsigned long addr, unsigned long arch_get_unmapped_area_topdown(struct file *filp, const unsigned long addr0, - const unsigned long len, const unsigned long pgoff, - const unsigned long flags) + const unsigned long len, const unsigned long pgoff, + const unsigned long flags, vm_flags_t vm_flags) { struct vm_area_struct *vma; struct mm_struct *mm = current->mm; diff --git a/arch/csky/abiv1/mmap.c b/arch/csky/abiv1/mmap.c index 7f826331d409..1047865e82a9 100644 --- a/arch/csky/abiv1/mmap.c +++ b/arch/csky/abiv1/mmap.c @@ -23,7 +23,8 @@ */ unsigned long arch_get_unmapped_area(struct file *filp, unsigned long addr, - unsigned long len, unsigned long pgoff, unsigned long flags) + unsigned long len, unsigned long pgoff, + unsigned long flags, vm_flags_t vm_flags) { struct mm_struct *mm = current->mm; struct vm_area_struct *vma; diff --git a/arch/loongarch/mm/mmap.c b/arch/loongarch/mm/mmap.c index 889030985135..914e82ff3f65 100644 --- a/arch/loongarch/mm/mmap.c +++ b/arch/loongarch/mm/mmap.c @@ -89,7 +89,8 @@ static unsigned long arch_get_unmapped_area_common(struct file *filp, } unsigned long arch_get_unmapped_area(struct file *filp, unsigned long addr0, - unsigned long len, unsigned long pgoff, unsigned long flags) + unsigned long len, unsigned long pgoff, unsigned long flags, + vm_flags_t vm_flags) { return arch_get_unmapped_area_common(filp, addr0, len, pgoff, flags, UP); @@ -101,7 +102,7 @@ unsigned long arch_get_unmapped_area(struct file *filp, unsigned long addr0, */ unsigned long arch_get_unmapped_area_topdown(struct file *filp, unsigned long addr0, unsigned long len, unsigned long pgoff, - unsigned long flags) + unsigned long flags, vm_flags_t vm_flags) { return arch_get_unmapped_area_common(filp, addr0, len, pgoff, flags, DOWN); diff --git a/arch/mips/mm/mmap.c b/arch/mips/mm/mmap.c index 7e11d7b58761..02bf5353efbd 100644 --- a/arch/mips/mm/mmap.c +++ b/arch/mips/mm/mmap.c @@ -110,7 +110,7 @@ unsigned long arch_get_unmapped_area(struct file *filp, unsigned long addr0, */ unsigned long arch_get_unmapped_area_topdown(struct file *filp, unsigned long addr0, unsigned long len, unsigned long pgoff, - unsigned long flags) + unsigned long flags, vm_flags_t vm_flags) { return arch_get_unmapped_area_common(filp, addr0, len, pgoff, flags, DOWN); diff --git a/arch/parisc/kernel/sys_parisc.c b/arch/parisc/kernel/sys_parisc.c index f7722451276e..f852fe274abe 100644 --- a/arch/parisc/kernel/sys_parisc.c +++ b/arch/parisc/kernel/sys_parisc.c @@ -167,7 +167,8 @@ static unsigned long arch_get_unmapped_area_common(struct file *filp, } unsigned long arch_get_unmapped_area(struct file *filp, unsigned long addr, - unsigned long len, unsigned long pgoff, unsigned long flags) + unsigned long len, unsigned long pgoff, unsigned long flags, + vm_flags_t vm_flags) { return arch_get_unmapped_area_common(filp, addr, len, pgoff, flags, UP); @@ -175,7 +176,7 @@ unsigned long arch_get_unmapped_area(struct file *filp, unsigned long addr, unsigned long arch_get_unmapped_area_topdown(struct file *filp, unsigned long addr, unsigned long len, unsigned long pgoff, - unsigned long flags) + unsigned long flags, vm_flags_t vm_flags) { return arch_get_unmapped_area_common(filp, addr, len, pgoff, flags, DOWN); diff --git a/arch/parisc/mm/hugetlbpage.c b/arch/parisc/mm/hugetlbpage.c index 0356199bd9e7..aa664f7ddb63 100644 --- a/arch/parisc/mm/hugetlbpage.c +++ b/arch/parisc/mm/hugetlbpage.c @@ -40,7 +40,7 @@ hugetlb_get_unmapped_area(struct file *file, unsigned long addr, addr = ALIGN(addr, huge_page_size(h)); /* we need to make sure the colouring is OK */ - return arch_get_unmapped_area(file, addr, len, pgoff, flags); + return arch_get_unmapped_area(file, addr, len, pgoff, flags, 0); } diff --git a/arch/powerpc/mm/book3s64/slice.c b/arch/powerpc/mm/book3s64/slice.c index ef3ce37f1bb3..ada6bf896ef8 100644 --- a/arch/powerpc/mm/book3s64/slice.c +++ b/arch/powerpc/mm/book3s64/slice.c @@ -637,7 +637,8 @@ unsigned long arch_get_unmapped_area(struct file *filp, unsigned long addr, unsigned long len, unsigned long pgoff, - unsigned long flags) + unsigned long flags, + vm_flags_t vm_flags) { if (radix_enabled()) return generic_get_unmapped_area(filp, addr, len, pgoff, flags); @@ -650,7 +651,8 @@ unsigned long arch_get_unmapped_area_topdown(struct file *filp, const unsigned long addr0, const unsigned long len, const unsigned long pgoff, - const unsigned long flags) + const unsigned long flags, + vm_flags_t vm_flags) { if (radix_enabled()) return generic_get_unmapped_area_topdown(filp, addr0, len, pgoff, flags); diff --git a/arch/s390/mm/mmap.c b/arch/s390/mm/mmap.c index 206756946589..96efa061ce01 100644 --- a/arch/s390/mm/mmap.c +++ b/arch/s390/mm/mmap.c @@ -82,7 +82,7 @@ static int get_align_mask(struct file *filp, unsigned long flags) unsigned long arch_get_unmapped_area(struct file *filp, unsigned long addr, unsigned long len, unsigned long pgoff, - unsigned long flags) + unsigned long flags, vm_flags_t vm_flags) { struct mm_struct *mm = current->mm; struct vm_area_struct *vma; @@ -117,7 +117,7 @@ unsigned long arch_get_unmapped_area(struct file *filp, unsigned long addr, unsigned long arch_get_unmapped_area_topdown(struct file *filp, unsigned long addr, unsigned long len, unsigned long pgoff, - unsigned long flags) + unsigned long flags, vm_flags_t vm_flags) { struct vm_area_struct *vma; struct mm_struct *mm = current->mm; diff --git a/arch/sh/mm/mmap.c b/arch/sh/mm/mmap.c index bee329d4149a..c442734d9b0c 100644 --- a/arch/sh/mm/mmap.c +++ b/arch/sh/mm/mmap.c @@ -52,7 +52,8 @@ static inline unsigned long COLOUR_ALIGN(unsigned long addr, } unsigned long arch_get_unmapped_area(struct file *filp, unsigned long addr, - unsigned long len, unsigned long pgoff, unsigned long flags) + unsigned long len, unsigned long pgoff, unsigned long flags, + vm_flags_t vm_flags) { struct mm_struct *mm = current->mm; struct vm_area_struct *vma; @@ -99,7 +100,7 @@ unsigned long arch_get_unmapped_area(struct file *filp, unsigned long addr, unsigned long arch_get_unmapped_area_topdown(struct file *filp, const unsigned long addr0, const unsigned long len, const unsigned long pgoff, - const unsigned long flags) + const unsigned long flags, vm_flags_t vm_flags) { struct vm_area_struct *vma; struct mm_struct *mm = current->mm; diff --git a/arch/sparc/kernel/sys_sparc_32.c b/arch/sparc/kernel/sys_sparc_32.c index 08a19727795c..80822f922e76 100644 --- a/arch/sparc/kernel/sys_sparc_32.c +++ b/arch/sparc/kernel/sys_sparc_32.c @@ -39,7 +39,7 @@ SYSCALL_DEFINE0(getpagesize) return PAGE_SIZE; /* Possibly older binaries want 8192 on sun4's? */ } -unsigned long arch_get_unmapped_area(struct file *filp, unsigned long addr, unsigned long len, unsigned long pgoff, unsigned long flags) +unsigned long arch_get_unmapped_area(struct file *filp, unsigned long addr, unsigned long len, unsigned long pgoff, unsigned long flags, vm_flags_t vm_flags) { struct vm_unmapped_area_info info = {}; diff --git a/arch/sparc/kernel/sys_sparc_64.c b/arch/sparc/kernel/sys_sparc_64.c index d9c3b34ca744..acade309dc2f 100644 --- a/arch/sparc/kernel/sys_sparc_64.c +++ b/arch/sparc/kernel/sys_sparc_64.c @@ -87,7 +87,7 @@ static inline unsigned long COLOR_ALIGN(unsigned long addr, return base + off; } -unsigned long arch_get_unmapped_area(struct file *filp, unsigned long addr, unsigned long len, unsigned long pgoff, unsigned long flags) +unsigned long arch_get_unmapped_area(struct file *filp, unsigned long addr, unsigned long len, unsigned long pgoff, unsigned long flags, vm_flags_t vm_flags) { struct mm_struct *mm = current->mm; struct vm_area_struct * vma; @@ -146,7 +146,7 @@ unsigned long arch_get_unmapped_area(struct file *filp, unsigned long addr, unsi unsigned long arch_get_unmapped_area_topdown(struct file *filp, const unsigned long addr0, const unsigned long len, const unsigned long pgoff, - const unsigned long flags) + const unsigned long flags, vm_flags_t vm_flags) { struct vm_area_struct *vma; struct mm_struct *mm = current->mm; diff --git a/arch/x86/include/asm/pgtable_64.h b/arch/x86/include/asm/pgtable_64.h index 3c4407271d08..7e9db77231ac 100644 --- a/arch/x86/include/asm/pgtable_64.h +++ b/arch/x86/include/asm/pgtable_64.h @@ -245,7 +245,6 @@ extern void cleanup_highmap(void); #define HAVE_ARCH_UNMAPPED_AREA #define HAVE_ARCH_UNMAPPED_AREA_TOPDOWN -#define HAVE_ARCH_UNMAPPED_AREA_VMFLAGS #define PAGE_AGP PAGE_KERNEL_NOCACHE #define HAVE_PAGE_AGP 1 diff --git a/arch/x86/kernel/sys_x86_64.c b/arch/x86/kernel/sys_x86_64.c index 01d7cd85ef97..87f8c9a71c49 100644 --- a/arch/x86/kernel/sys_x86_64.c +++ b/arch/x86/kernel/sys_x86_64.c @@ -121,7 +121,7 @@ static inline unsigned long stack_guard_placement(vm_flags_t vm_flags) } unsigned long -arch_get_unmapped_area_vmflags(struct file *filp, unsigned long addr, unsigned long len, +arch_get_unmapped_area(struct file *filp, unsigned long addr, unsigned long len, unsigned long pgoff, unsigned long flags, vm_flags_t vm_flags) { struct mm_struct *mm = current->mm; @@ -158,7 +158,7 @@ arch_get_unmapped_area_vmflags(struct file *filp, unsigned long addr, unsigned l } unsigned long -arch_get_unmapped_area_topdown_vmflags(struct file *filp, unsigned long addr0, +arch_get_unmapped_area_topdown(struct file *filp, unsigned long addr0, unsigned long len, unsigned long pgoff, unsigned long flags, vm_flags_t vm_flags) { @@ -228,20 +228,5 @@ arch_get_unmapped_area_topdown_vmflags(struct file *filp, unsigned long addr0, * can happen with large stack limits and large mmap() * allocations. */ - return arch_get_unmapped_area(filp, addr0, len, pgoff, flags); -} - -unsigned long -arch_get_unmapped_area(struct file *filp, unsigned long addr, - unsigned long len, unsigned long pgoff, unsigned long flags) -{ - return arch_get_unmapped_area_vmflags(filp, addr, len, pgoff, flags, 0); -} - -unsigned long -arch_get_unmapped_area_topdown(struct file *filp, const unsigned long addr, - const unsigned long len, const unsigned long pgoff, - const unsigned long flags) -{ - return arch_get_unmapped_area_topdown_vmflags(filp, addr, len, pgoff, flags, 0); + return arch_get_unmapped_area(filp, addr0, len, pgoff, flags, 0); } diff --git a/arch/xtensa/kernel/syscall.c b/arch/xtensa/kernel/syscall.c index b3c2450d6f23..7f048d368dba 100644 --- a/arch/xtensa/kernel/syscall.c +++ b/arch/xtensa/kernel/syscall.c @@ -55,7 +55,8 @@ asmlinkage long xtensa_fadvise64_64(int fd, int advice, #ifdef CONFIG_MMU unsigned long arch_get_unmapped_area(struct file *filp, unsigned long addr, - unsigned long len, unsigned long pgoff, unsigned long flags) + unsigned long len, unsigned long pgoff, unsigned long flags, + vm_flgs_t vm_flags) { struct vm_area_struct *vmm; struct vma_iterator vmi; diff --git a/include/linux/sched/mm.h b/include/linux/sched/mm.h index 91546493c43d..c4d34abc45d4 100644 --- a/include/linux/sched/mm.h +++ b/include/linux/sched/mm.h @@ -179,27 +179,20 @@ static inline void mm_update_next_owner(struct mm_struct *mm) extern void arch_pick_mmap_layout(struct mm_struct *mm, struct rlimit *rlim_stack); -extern unsigned long -arch_get_unmapped_area(struct file *, unsigned long, unsigned long, - unsigned long, unsigned long); -extern unsigned long + +unsigned long +arch_get_unmapped_area(struct file *filp, unsigned long addr, + unsigned long len, unsigned long pgoff, + unsigned long flags, vm_flags_t vm_flags); +unsigned long arch_get_unmapped_area_topdown(struct file *filp, unsigned long addr, - unsigned long len, unsigned long pgoff, - unsigned long flags); + unsigned long len, unsigned long pgoff, + unsigned long flags, vm_flags_t); unsigned long mm_get_unmapped_area(struct mm_struct *mm, struct file *filp, unsigned long addr, unsigned long len, unsigned long pgoff, unsigned long flags); -unsigned long -arch_get_unmapped_area_vmflags(struct file *filp, unsigned long addr, - unsigned long len, unsigned long pgoff, - unsigned long flags, vm_flags_t vm_flags); -unsigned long -arch_get_unmapped_area_topdown_vmflags(struct file *filp, unsigned long addr, - unsigned long len, unsigned long pgoff, - unsigned long flags, vm_flags_t); - unsigned long mm_get_unmapped_area_vmflags(struct mm_struct *mm, struct file *filp, unsigned long addr, diff --git a/mm/mmap.c b/mm/mmap.c index d0dfc85b209b..7528146f886f 100644 --- a/mm/mmap.c +++ b/mm/mmap.c @@ -1821,7 +1821,7 @@ generic_get_unmapped_area(struct file *filp, unsigned long addr, unsigned long arch_get_unmapped_area(struct file *filp, unsigned long addr, unsigned long len, unsigned long pgoff, - unsigned long flags) + unsigned long flags, vm_flags_t vm_flags) { return generic_get_unmapped_area(filp, addr, len, pgoff, flags); } @@ -1885,38 +1885,21 @@ generic_get_unmapped_area_topdown(struct file *filp, unsigned long addr, unsigned long arch_get_unmapped_area_topdown(struct file *filp, unsigned long addr, unsigned long len, unsigned long pgoff, - unsigned long flags) + unsigned long flags, vm_flags_t vm_flags) { return generic_get_unmapped_area_topdown(filp, addr, len, pgoff, flags); } #endif -#ifndef HAVE_ARCH_UNMAPPED_AREA_VMFLAGS -unsigned long -arch_get_unmapped_area_vmflags(struct file *filp, unsigned long addr, unsigned long len, - unsigned long pgoff, unsigned long flags, vm_flags_t vm_flags) -{ - return arch_get_unmapped_area(filp, addr, len, pgoff, flags); -} - -unsigned long -arch_get_unmapped_area_topdown_vmflags(struct file *filp, unsigned long addr, - unsigned long len, unsigned long pgoff, - unsigned long flags, vm_flags_t vm_flags) -{ - return arch_get_unmapped_area_topdown(filp, addr, len, pgoff, flags); -} -#endif - unsigned long mm_get_unmapped_area_vmflags(struct mm_struct *mm, struct file *filp, unsigned long addr, unsigned long len, unsigned long pgoff, unsigned long flags, vm_flags_t vm_flags) { if (test_bit(MMF_TOPDOWN, &mm->flags)) - return arch_get_unmapped_area_topdown_vmflags(filp, addr, len, pgoff, - flags, vm_flags); - return arch_get_unmapped_area_vmflags(filp, addr, len, pgoff, flags, vm_flags); + return arch_get_unmapped_area_topdown(filp, addr, len, pgoff, + flags, vm_flags); + return arch_get_unmapped_area(filp, addr, len, pgoff, flags, vm_flags); } unsigned long @@ -1978,8 +1961,8 @@ mm_get_unmapped_area(struct mm_struct *mm, struct file *file, unsigned long pgoff, unsigned long flags) { if (test_bit(MMF_TOPDOWN, &mm->flags)) - return arch_get_unmapped_area_topdown(file, addr, len, pgoff, flags); - return arch_get_unmapped_area(file, addr, len, pgoff, flags); + return arch_get_unmapped_area_topdown(file, addr, len, pgoff, flags, 0); + return arch_get_unmapped_area(file, addr, len, pgoff, flags, 0); } EXPORT_SYMBOL(mm_get_unmapped_area); From patchwork Mon Sep 2 19:08:14 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Mark Brown X-Patchwork-Id: 13787654 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 230E11A3041; 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dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="ufsKnZLL" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 6CF47C4CEC9; Mon, 2 Sep 2024 19:08:53 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1725304143; bh=nejS97KnA2Qms3Gvgo3SMj9sJCiVfLci6/Mfi/Rsw8U=; h=From:Date:Subject:References:In-Reply-To:To:Cc:From; b=ufsKnZLLQwEHAwpacZdtysRg/9QTknqhrlzPG0gTIS2ybE0mNRT06SNEuUXiZCc52 rL+kMleAwcxpyJCXunOkVdq2gkI0N4rXboHt0oCmSgcGWyIDtKyzqE1RLH6FGpCehJ Nca5DzLVoAyJkCzqFoxcM2eyWPTVeaxie9bJU/MGsXST6olZu3DlCT9zPLmzlDYiDo 26pYLD97shqH/Vu3qR8DrMi1U/FYh0ChQcfnXrx7ZvWkDhG+mSHja+QAtiFSNdNyh4 wOsgcVvHRsT0fJO5jdxMGCUzxcJPTzigqd/TdNVNvI1OlUf5pvD6mFYRBg0yAvRUbY 6Q9pMzCUd4xCg== From: Mark Brown Date: Mon, 02 Sep 2024 20:08:14 +0100 Subject: [PATCH 2/3] mm: Pass vm_flags to generic_get_unmapped_area() Precedence: bulk X-Mailing-List: linux-sh@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Message-Id: <20240902-mm-generic-shadow-stack-guard-v1-2-9acda38b3dd3@kernel.org> References: <20240902-mm-generic-shadow-stack-guard-v1-0-9acda38b3dd3@kernel.org> In-Reply-To: <20240902-mm-generic-shadow-stack-guard-v1-0-9acda38b3dd3@kernel.org> To: Richard Henderson , Ivan Kokshaysky , Matt Turner , Vineet Gupta , Russell King , Guo Ren , Huacai Chen , WANG Xuerui , "James E.J. Bottomley" , Helge Deller , Michael Ellerman , Nicholas Piggin , Christophe Leroy , Naveen N Rao , Alexander Gordeev , Gerald Schaefer , Heiko Carstens , Vasily Gorbik , Christian Borntraeger , Sven Schnelle , Yoshinori Sato , Rich Felker , John Paul Adrian Glaubitz , "David S. Miller" , Andreas Larsson , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , x86@kernel.org, "H. Peter Anvin" , Chris Zankel , Max Filippov , Andrew Morton , "Liam R. Howlett" , Vlastimil Babka , Lorenzo Stoakes Cc: Catalin Marinas , Will Deacon , Deepak Gupta , linux-arm-kernel@lists.infradead.org, linux-alpha@vger.kernel.org, linux-kernel@vger.kernel.org, linux-snps-arc@lists.infradead.org, linux-arm-kernel@lists.infradead.org, linux-csky@vger.kernel.org, loongarch@lists.linux.dev, linux-parisc@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-s390@vger.kernel.org, linux-sh@vger.kernel.org, sparclinux@vger.kernel.org, linux-mm@kvack.org, Mark Brown X-Mailer: b4 0.15-dev-37811 X-Developer-Signature: v=1; a=openpgp-sha256; l=4018; i=broonie@kernel.org; h=from:subject:message-id; bh=nejS97KnA2Qms3Gvgo3SMj9sJCiVfLci6/Mfi/Rsw8U=; b=owEBbQGS/pANAwAKASTWi3JdVIfQAcsmYgBm1g0v9w9lBiTjIu5lnJumAd7oKheioErj5Av8o9p9 xjbw4dqJATMEAAEKAB0WIQSt5miqZ1cYtZ/in+ok1otyXVSH0AUCZtYNLwAKCRAk1otyXVSH0FX7B/ 9slZJSbOLk1zaWaFIlxJH7fsKOjdUxsEOGWqCfQQ7SzheizYCzQY9YUFbpp6x55PbW9KNdQ/ikhexU ts50XikTINzfTgQ5Nv4584Ko0cc5QH9Vvp0f0XFS3G8wep0Uq6vKMRlTzj2D8sUxFbzP65JLa882Vz pTQ7zTU/tzgbq3wMWfLtM/IqmqQJPSikIxU5k6R1bMD0jw/s2LwtAq5lD5a/g30apMg/klNkyAShDn JdrvWvSR2DLgHDfOSFSLUlLXNVTd61W01f/ngaSuv3L1ymol4mTPWXexFqqN6BKbYj9tM2RHTYuHDn LkE9GrCLQjRp0t+wnKJpiI8cN1kT2+ X-Developer-Key: i=broonie@kernel.org; a=openpgp; fpr=3F2568AAC26998F9E813A1C5C3F436CA30F5D8EB In preparation for using vm_flags to ensure guard pages for shadow stacks supply them as an argument to generic_get_unmapped_area(). The only user outside of the core code is the PowerPC book3s64 implementation which is trivially wrapping the generic implementation in the radix_enabled() case. Signed-off-by: Mark Brown Acked-by: Lorenzo Stoakes (for mm/mmap.c part) Reviewed-by: Liam R. Howlett Acked-by: Michael Ellerman (powerpc) Reviewed-by: Deepak Gupta --- arch/powerpc/mm/book3s64/slice.c | 4 ++-- include/linux/sched/mm.h | 4 ++-- mm/mmap.c | 10 ++++++---- 3 files changed, 10 insertions(+), 8 deletions(-) diff --git a/arch/powerpc/mm/book3s64/slice.c b/arch/powerpc/mm/book3s64/slice.c index ada6bf896ef8..87307d0fc3b8 100644 --- a/arch/powerpc/mm/book3s64/slice.c +++ b/arch/powerpc/mm/book3s64/slice.c @@ -641,7 +641,7 @@ unsigned long arch_get_unmapped_area(struct file *filp, vm_flags_t vm_flags) { if (radix_enabled()) - return generic_get_unmapped_area(filp, addr, len, pgoff, flags); + return generic_get_unmapped_area(filp, addr, len, pgoff, flags, vm_flags); return slice_get_unmapped_area(addr, len, flags, mm_ctx_user_psize(¤t->mm->context), 0); @@ -655,7 +655,7 @@ unsigned long arch_get_unmapped_area_topdown(struct file *filp, vm_flags_t vm_flags) { if (radix_enabled()) - return generic_get_unmapped_area_topdown(filp, addr0, len, pgoff, flags); + return generic_get_unmapped_area_topdown(filp, addr0, len, pgoff, flags, vm_flags); return slice_get_unmapped_area(addr0, len, flags, mm_ctx_user_psize(¤t->mm->context), 1); diff --git a/include/linux/sched/mm.h b/include/linux/sched/mm.h index c4d34abc45d4..07bb8d4181d7 100644 --- a/include/linux/sched/mm.h +++ b/include/linux/sched/mm.h @@ -204,11 +204,11 @@ unsigned long mm_get_unmapped_area_vmflags(struct mm_struct *mm, unsigned long generic_get_unmapped_area(struct file *filp, unsigned long addr, unsigned long len, unsigned long pgoff, - unsigned long flags); + unsigned long flags, vm_flags_t vm_flags); unsigned long generic_get_unmapped_area_topdown(struct file *filp, unsigned long addr, unsigned long len, unsigned long pgoff, - unsigned long flags); + unsigned long flags, vm_flags_t vm_flags); #else static inline void arch_pick_mmap_layout(struct mm_struct *mm, struct rlimit *rlim_stack) {} diff --git a/mm/mmap.c b/mm/mmap.c index 7528146f886f..b06ba847c96e 100644 --- a/mm/mmap.c +++ b/mm/mmap.c @@ -1789,7 +1789,7 @@ unsigned long vm_unmapped_area(struct vm_unmapped_area_info *info) unsigned long generic_get_unmapped_area(struct file *filp, unsigned long addr, unsigned long len, unsigned long pgoff, - unsigned long flags) + unsigned long flags, vm_flags_t vm_flags) { struct mm_struct *mm = current->mm; struct vm_area_struct *vma, *prev; @@ -1823,7 +1823,8 @@ arch_get_unmapped_area(struct file *filp, unsigned long addr, unsigned long len, unsigned long pgoff, unsigned long flags, vm_flags_t vm_flags) { - return generic_get_unmapped_area(filp, addr, len, pgoff, flags); + return generic_get_unmapped_area(filp, addr, len, pgoff, flags, + vm_flags); } #endif @@ -1834,7 +1835,7 @@ arch_get_unmapped_area(struct file *filp, unsigned long addr, unsigned long generic_get_unmapped_area_topdown(struct file *filp, unsigned long addr, unsigned long len, unsigned long pgoff, - unsigned long flags) + unsigned long flags, vm_flags_t vm_flags) { struct vm_area_struct *vma, *prev; struct mm_struct *mm = current->mm; @@ -1887,7 +1888,8 @@ arch_get_unmapped_area_topdown(struct file *filp, unsigned long addr, unsigned long len, unsigned long pgoff, unsigned long flags, vm_flags_t vm_flags) { - return generic_get_unmapped_area_topdown(filp, addr, len, pgoff, flags); + return generic_get_unmapped_area_topdown(filp, addr, len, pgoff, flags, + vm_flags); } #endif From patchwork Mon Sep 2 19:08:15 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Mark Brown X-Patchwork-Id: 13787655 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id CFE454F881; Mon, 2 Sep 2024 19:09:15 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1725304156; cv=none; b=jBksFvdj/BESF9nCuWBW+yJdRPvRwfGMpuKcfI5dIrO1paf6IK8IrK7kaOUzYEfG8BtxjICafKwwQffEkEeHnTBQ6PsQ6OThT4fouj8+nSwJQNLv65VYUJaibHJt238B9CsxGVsqxl2xyZOHTJs9yb4BlVb/Tqns9Xi6tcsLqSs= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1725304156; c=relaxed/simple; bh=0/hF44fORO0Gery9A2B+FBHrfD+c3aFRzdrAQPNITJE=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=VOi2ojDN/TUBwltC0brmE+e8rUpjdSIjIylUYjsFUcQNxsxLqKSTXUb9w1nJlZKMvjoIDa13iyL88Tp70Z/HfzZgfpOsc6HYY3KPMgODoCON20IakRznGn0jOKXkZtCdy87YSTpJUM5MKeQce7MJKYtHp5A7a7RcW9CyThxHT4g= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=N9sI26+Y; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="N9sI26+Y" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 69C9CC4CEC8; Mon, 2 Sep 2024 19:09:03 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1725304155; bh=0/hF44fORO0Gery9A2B+FBHrfD+c3aFRzdrAQPNITJE=; h=From:Date:Subject:References:In-Reply-To:To:Cc:From; b=N9sI26+YB1BFPD9a0+oQnaOYoEp8JD6VMjANXfF4vZthYCbAVo/geEan5PCYE/5YG KyNtsWx0ZmtF4GI6OmQqvHuRlOVg8nJg01jLUUvrGS8k0qXeZSz9H6+XV52mPp5OT9 SiFxv0FaUoXnD8v0PwGJEyUEBBupfs/d/2YxBDJJeebGN6LeO2fcg3zg8MsSGoraop tcocc1osS+PVlcQOrKjq5qbDCptBphGD5397tCq3uoQScdTyYNG0/L00MB3+u9eT91 Po9TaiUwdOyyXQuJiSHGiI3yZh0UNZiv/JBij7SxkXKL2T4XOAiQx7+fQg9SMU8IKV ZubyoBQssJRwg== From: Mark Brown Date: Mon, 02 Sep 2024 20:08:15 +0100 Subject: [PATCH 3/3] mm: Care about shadow stack guard gap when getting an unmapped area Precedence: bulk X-Mailing-List: linux-sh@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Message-Id: <20240902-mm-generic-shadow-stack-guard-v1-3-9acda38b3dd3@kernel.org> References: <20240902-mm-generic-shadow-stack-guard-v1-0-9acda38b3dd3@kernel.org> In-Reply-To: <20240902-mm-generic-shadow-stack-guard-v1-0-9acda38b3dd3@kernel.org> To: Richard Henderson , Ivan Kokshaysky , Matt Turner , Vineet Gupta , Russell King , Guo Ren , Huacai Chen , WANG Xuerui , "James E.J. Bottomley" , Helge Deller , Michael Ellerman , Nicholas Piggin , Christophe Leroy , Naveen N Rao , Alexander Gordeev , Gerald Schaefer , Heiko Carstens , Vasily Gorbik , Christian Borntraeger , Sven Schnelle , Yoshinori Sato , Rich Felker , John Paul Adrian Glaubitz , "David S. Miller" , Andreas Larsson , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , x86@kernel.org, "H. Peter Anvin" , Chris Zankel , Max Filippov , Andrew Morton , "Liam R. Howlett" , Vlastimil Babka , Lorenzo Stoakes Cc: Catalin Marinas , Will Deacon , Deepak Gupta , linux-arm-kernel@lists.infradead.org, linux-alpha@vger.kernel.org, linux-kernel@vger.kernel.org, linux-snps-arc@lists.infradead.org, linux-arm-kernel@lists.infradead.org, linux-csky@vger.kernel.org, loongarch@lists.linux.dev, linux-parisc@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-s390@vger.kernel.org, linux-sh@vger.kernel.org, sparclinux@vger.kernel.org, linux-mm@kvack.org, Mark Brown , Rick Edgecombe X-Mailer: b4 0.15-dev-37811 X-Developer-Signature: v=1; a=openpgp-sha256; l=2208; i=broonie@kernel.org; h=from:subject:message-id; bh=0/hF44fORO0Gery9A2B+FBHrfD+c3aFRzdrAQPNITJE=; b=owEBbQGS/pANAwAKASTWi3JdVIfQAcsmYgBm1g0waix/xDVLlXSaTD4u/rRM+Xov1S4sJqN9L4bW qlKpuiaJATMEAAEKAB0WIQSt5miqZ1cYtZ/in+ok1otyXVSH0AUCZtYNMAAKCRAk1otyXVSH0D8aCA CF9K7LlaivE2EybLobtlEVyd3x4/yQFEmQzQPnmLchhUTmpNDtOjAWH5nWJB5csnuTjOxnJKPohxjU OlGKNnXZ4xzXd0tKckj2SwQe75FXPlRlPAsaelj3L+B0sFx+eaxKOJptUrnxX0L5qOqpZ7yxSSg7Lp QqS957ontDIGI1sWL7Jr883SmGUsD3O1znFCoOJSJgM0E4BSv5EsC6tkrAy58jG3VQAOqtDHm5b8r9 9yDRusfPXLA88jssbTu7Bg4R1DSDS6OnJlDIn0c2CKKk/Cw+o6jzMxTmxntZMd5Iiz1JndFzNYziYB 5TydVe5LsQPAyaA9p8ecpXQVC+h/i/ X-Developer-Key: i=broonie@kernel.org; a=openpgp; fpr=3F2568AAC26998F9E813A1C5C3F436CA30F5D8EB As covered in the commit log for c44357c2e76b ("x86/mm: care about shadow stack guard gap during placement") our current mmap() implementation does not take care to ensure that a new mapping isn't placed with existing mappings inside it's own guard gaps. This is particularly important for shadow stacks since if two shadow stacks end up getting placed adjacent to each other then they can overflow into each other which weakens the protection offered by the feature. On x86 there is a custom arch_get_unmapped_area() which was updated by the above commit to cover this case by specifying a start_gap for allocations with VM_SHADOW_STACK. Both arm64 and RISC-V have equivalent features and use the generic implementation of arch_get_unmapped_area() so let's make the equivalent change there so they also don't get shadow stack pages placed without guard pages. Architectures which do not have this feature will define VM_SHADOW_STACK to VM_NONE and hence be unaffected. Suggested-by: Rick Edgecombe Signed-off-by: Mark Brown Acked-by: Lorenzo Stoakes Reviewed-by: Deepak Gupta --- mm/mmap.c | 10 ++++++++++ 1 file changed, 10 insertions(+) diff --git a/mm/mmap.c b/mm/mmap.c index b06ba847c96e..902c482b6084 100644 --- a/mm/mmap.c +++ b/mm/mmap.c @@ -1753,6 +1753,14 @@ static unsigned long unmapped_area_topdown(struct vm_unmapped_area_info *info) return gap; } +static inline unsigned long stack_guard_placement(vm_flags_t vm_flags) +{ + if (vm_flags & VM_SHADOW_STACK) + return PAGE_SIZE; + + return 0; +} + /* * Search for an unmapped address range. * @@ -1814,6 +1822,7 @@ generic_get_unmapped_area(struct file *filp, unsigned long addr, info.length = len; info.low_limit = mm->mmap_base; info.high_limit = mmap_end; + info.start_gap = stack_guard_placement(vm_flags); return vm_unmapped_area(&info); } @@ -1863,6 +1872,7 @@ generic_get_unmapped_area_topdown(struct file *filp, unsigned long addr, info.length = len; info.low_limit = PAGE_SIZE; info.high_limit = arch_get_mmap_base(addr, mm->mmap_base); + info.start_gap = stack_guard_placement(vm_flags); addr = vm_unmapped_area(&info); /*