From patchwork Wed Sep 4 16:57:59 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Mark Brown X-Patchwork-Id: 13791220 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 032141DA31D; Wed, 4 Sep 2024 17:03:58 +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=1725469439; cv=none; b=Vl+2Wknj+TrcgB0RbdZlIz3A7uyzZrU2HKArnq2iku2N6T9HEJ8iGQdRg2qVzJZG9Vw/0Sr9mcbzCMrUxiJfGCMCuYvPrFzXgWms4XAiRuY1SK27umNcqmgodSOaVWI+WHV1g0CdbPGBANtWRr4jRKwzpeHjOyMG+PaTZ+hVjhU= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1725469439; c=relaxed/simple; bh=iMGpBKLUd3bvO8uaih/7IniDLWm5CRUl+/lD6PfEr9k=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=YfZDqgb79ANyX6o3oOpRwgWxRFw3ef79j+7jFlXIuUnFi0UAawvpwW5/xNTEFEDMDOhpGQFXWkB1wRbgn/ArSfsYVKIOmHLHxv6MuYjqme0Bi5xWg+dYKBHRgusU72fVxuMr2VQ3VRgwmeqTuqO8IwkTTtoLzkbNGfhRTXap/xo= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=m7eodkhq; 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="m7eodkhq" Received: by smtp.kernel.org (Postfix) with ESMTPSA id DCC5DC4CECA; Wed, 4 Sep 2024 17:03:48 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1725469438; bh=iMGpBKLUd3bvO8uaih/7IniDLWm5CRUl+/lD6PfEr9k=; h=From:Date:Subject:References:In-Reply-To:To:Cc:From; b=m7eodkhq0RErBfervK5Bsmxdg8am7kwijD8ykXbJt8mPkTG9IyB5JRY7WVj18ih1k x6sviigYtUG9BJn7PjimSCYTiJax14dADD7HnpfSm2PAigva7JirSV6S46K6LODPFA KPYwdLsRlVMqKSKMsnPSKatBddYbWpgwAzFq60M4p83BVMbylSayrUNMmj2G9HDevP 466po23vnLB/ToM0xSzsiGe+HFmrUtErW7o3cEslbIT6TU3DhI8UDga3dU2IPPdJgp VEudVDz99BKPSf2D0quAP/QZEMNwuVoq5fpiz5tW1oSoZDamdlW82UwAL7TGaXCbgo ZTrsBG1oCizDA== From: Mark Brown Date: Wed, 04 Sep 2024 17:57:59 +0100 Subject: [PATCH v2 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: <20240904-mm-generic-shadow-stack-guard-v2-1-a46b8b6dc0ed@kernel.org> References: <20240904-mm-generic-shadow-stack-guard-v2-0-a46b8b6dc0ed@kernel.org> In-Reply-To: <20240904-mm-generic-shadow-stack-guard-v2-0-a46b8b6dc0ed@kernel.org> To: Richard Henderson , Ivan Kokshaysky , Matt Turner , Vineet Gupta , Russell King , Guo Ren , Huacai Chen , WANG Xuerui , Thomas Bogendoerfer , "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: 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-mips@vger.kernel.org, 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, "Liam R. Howlett" , Mark Brown X-Mailer: b4 0.15-dev-99b12 X-Developer-Signature: v=1; a=openpgp-sha256; l=19799; i=broonie@kernel.org; h=from:subject:message-id; bh=iMGpBKLUd3bvO8uaih/7IniDLWm5CRUl+/lD6PfEr9k=; b=owEBbQGS/pANAwAKASTWi3JdVIfQAcsmYgBm2JLow6fydDORW8BLsjyWPaeHLJli7+BVdNkzgOZq Z3JAMSiJATMEAAEKAB0WIQSt5miqZ1cYtZ/in+ok1otyXVSH0AUCZtiS6AAKCRAk1otyXVSH0AY3B/ 4qFpEVm4FBwn/XqLJ5l60W8/mejomvic6kPHt4uTKdPTpx4I1N7T5YHN+J7w8ZXN3E8/qFpLUyR8rN Ff/3OgHNcpYONXtLKceT4pSFZod0dq7DmuKBx1ST0uk+jpplwBcfJ0v7TY8TOjcLoEnwVQYmcUH4zt dSiK66q0W6W0cHOXTxcM7SKXCewSuJqr26/jCatFCPJ9KkgcnbOsW/RfsqQua0j7Jgu4YfmaUPIQZ4 oISt6gLd1jWjflRY9CEzE0eJ1zbqwBXxajtrITfd8FRwStGQzQdrlj1em+Cm5XfMGo0bmvc2FttROI d7bjiMYWrJ+nP8RsahVq67MRp3QWpe 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. Acked-by: Lorenzo Stoakes Reviewed-by: Liam R. Howlett Acked-by: Helge Deller # parisc Signed-off-by: Mark Brown --- 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 | 5 +++-- 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, 51 insertions(+), 81 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..5d2a1225785b 100644 --- a/arch/mips/mm/mmap.c +++ b/arch/mips/mm/mmap.c @@ -98,7 +98,8 @@ 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); @@ -110,7 +111,7 @@ 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..dc54f854c2f5 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_flags_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 Wed Sep 4 16:58:00 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Mark Brown X-Patchwork-Id: 13791221 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 29AA11E00B6; 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dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="F1QsO8bB" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 1404DC4CEC6; Wed, 4 Sep 2024 17:03:58 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1725469448; bh=68K3QvD0tkKZDAR0UpFpD5XCk8KfcxipD1vhxu8hMF4=; h=From:Date:Subject:References:In-Reply-To:To:Cc:From; b=F1QsO8bBJsx0AmPMFiW+aZLLp30OJ6WLUYtazU9cKiD6dYSxRrM5367mxKhnrYiYR 85yB8fFfMOjKTBpSlO8MxTRyv/+24AMKHEZNs759hHseiBj/tQt8LtzNo3gCqV7zJC uQh2rfX5CP6fSwpG+0wWFMriyE1+Q3TPMGbaKlm0vf/W8yTi6YtQEtz57I1nH30eGI uk1925ANdluBVwDdwvc2Uf445CgIHw/GtnY5jubFmpPqI82baUpZ0luZINbPivJThF /Qam2M175ofqQE8+/UGiTVrujbpbV7dCEBmi8Bo0pRE+eOwh3Yh5xEtK4CuLi+kg5V YjDq5wP3d56DQ== From: Mark Brown Date: Wed, 04 Sep 2024 17:58:00 +0100 Subject: [PATCH v2 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: <20240904-mm-generic-shadow-stack-guard-v2-2-a46b8b6dc0ed@kernel.org> References: <20240904-mm-generic-shadow-stack-guard-v2-0-a46b8b6dc0ed@kernel.org> In-Reply-To: <20240904-mm-generic-shadow-stack-guard-v2-0-a46b8b6dc0ed@kernel.org> To: Richard Henderson , Ivan Kokshaysky , Matt Turner , Vineet Gupta , Russell King , Guo Ren , Huacai Chen , WANG Xuerui , Thomas Bogendoerfer , "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: 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-mips@vger.kernel.org, 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, "Liam R. Howlett" , Mark Brown X-Mailer: b4 0.15-dev-99b12 X-Developer-Signature: v=1; a=openpgp-sha256; l=4205; i=broonie@kernel.org; h=from:subject:message-id; bh=68K3QvD0tkKZDAR0UpFpD5XCk8KfcxipD1vhxu8hMF4=; b=owEBbQGS/pANAwAKASTWi3JdVIfQAcsmYgBm2JLomVTv4ECj2BO6KAA82Rg2LfwONZpcDKcZ/rOe Hb8SxguJATMEAAEKAB0WIQSt5miqZ1cYtZ/in+ok1otyXVSH0AUCZtiS6AAKCRAk1otyXVSH0NQyB/ 9kxVcf9SZZ8gEenXIUM2v+Sc6WxUmySDKe8lr2m+hILlbK4d90FD7dZLYCCDeqEkNNrGh6dxpDiVEV hgDmQdrZolUYW4Y/p0jjVeCPzreQXwXMZ8W7N1D5N/l3wwkb+vqQ2RrrMKJvOtbhi0bp2xlKOK1YUk Xa2D8ExFcS60FeUbuVMhU7VgyzPwDG2vup548nR3kM6HbkaB9mUGdYgfOtvd53NRTyvp0fcvcw/+v1 p7p/kh7y4x1kYmGXa2Fhb2LKN3b8Jefvr2v8QIwR+T8VtgPWj4GQAuO+p7ai3SjpR3X5Rsd6NwJmYS YFA9nPiuXiHzme8MHUHh0LCDrrUpLW 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. No functional changes. Acked-by: Lorenzo Stoakes Reviewed-by: Liam R. Howlett Acked-by: Michael Ellerman Signed-off-by: Mark Brown --- 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 Wed Sep 4 16:58:01 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Mark Brown X-Patchwork-Id: 13791222 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 0DBFC1E0B86; Wed, 4 Sep 2024 17:04:18 +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=1725469459; cv=none; b=W+p7WJ1O3bz4E/W0RCv5D/IEQDRDZJ9OODBaLFs7DjTuD2AiH+mBXCU73qNYTMxsACa0M3Ajfd42f2QcMyzHISSY9qH+gk/UieX7qsDXGazcZ9DF1EHNsv0qbn9a8w28wjAoKqdIlUUW83sf9o7Rt0h5BLuVGWMhctleE9nJcYY= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1725469459; c=relaxed/simple; bh=6l7d6i2Hr/t16H3e0PM6ntsqOX0xtByvRrAFpx2RPdc=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=kESPip5BobWZIhi9sdTWSUOLp0o3/V7ELFNUx8a3i7S4lx6VE9ILANOyBUCfsP0xt+IBslYSwVHKKuOm8hEYvtKdmwepAGKHd0aq/8Aao8j9ZNZxc4NqXYgeXOjUOpBlZDGKRe+INadF43Acih7pUdSG2lK171zZcdSkPfkM4Ho= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=XMng1+N5; 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="XMng1+N5" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 1E2ECC4CECB; Wed, 4 Sep 2024 17:04:08 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1725469458; bh=6l7d6i2Hr/t16H3e0PM6ntsqOX0xtByvRrAFpx2RPdc=; h=From:Date:Subject:References:In-Reply-To:To:Cc:From; b=XMng1+N5KmI2Uyam4ahGOmJ7SA6LJYTXKVjx7qG8VnUZ/zUuGhRBCUkXKze2d/h2W qvk9lXkZAy6Y05LO0D8t2nFprSfQ7TcDWzQJu8SE80qNBE+/r6k3g83BIKWOzMfOt/ Dvpd5qWmKHpFvZ2SytdtRA/ewzxfCdXGeHxRiiWyHN4p2CWQTl0lHTEU4UgysXWzN2 eTOvyqyDhTsz/6ctIBuFArpRcUT1qm+ZYrAJVgsZe+irs/+81QH88lWveZJX5wrZrg OTOm7mY8GpWO9fbBe5Sz+TeGAp/qLFj/uFen9cZ5SvcQauQXuNRCmgGBYLVs1L2zqm CIGueYv9nSccQ== From: Mark Brown Date: Wed, 04 Sep 2024 17:58:01 +0100 Subject: [PATCH v2 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: <20240904-mm-generic-shadow-stack-guard-v2-3-a46b8b6dc0ed@kernel.org> References: <20240904-mm-generic-shadow-stack-guard-v2-0-a46b8b6dc0ed@kernel.org> In-Reply-To: <20240904-mm-generic-shadow-stack-guard-v2-0-a46b8b6dc0ed@kernel.org> To: Richard Henderson , Ivan Kokshaysky , Matt Turner , Vineet Gupta , Russell King , Guo Ren , Huacai Chen , WANG Xuerui , Thomas Bogendoerfer , "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: 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-mips@vger.kernel.org, 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, Rick Edgecombe , Mark Brown X-Mailer: b4 0.15-dev-99b12 X-Developer-Signature: v=1; a=openpgp-sha256; l=2551; i=broonie@kernel.org; h=from:subject:message-id; bh=6l7d6i2Hr/t16H3e0PM6ntsqOX0xtByvRrAFpx2RPdc=; b=owEBbQGS/pANAwAKASTWi3JdVIfQAcsmYgBm2JLp8oAy9lYwTYiPgligR57zoDd7L+at5nOq93BI UyufcpKJATMEAAEKAB0WIQSt5miqZ1cYtZ/in+ok1otyXVSH0AUCZtiS6QAKCRAk1otyXVSH0OADB/ 0ch6Ppo1cUyP74KOdaZaA30djq+AGYfXlBTOUWViXVC9fGK3bpaqsBB0Cfo7Fu6OsGVc21oO0/yUH1 YrAVYn6NPOHjgywpcI1TnkgqUaxfBOur+h4alPeKfO22P8IGuFmDQWUyfu/9w5PhhvsetXQF8HjY3+ VA0L3qH2XKq516PsycNgfFI7aYDz9EL8tCzzuTsMp8jhgeTHcVNNcxzbWDDBDU5qQBsU5P9IwQfOAx OuEH/w/+Xqho79dLxhqBNChGpSjBv7foaNTf0PLA9gi1zV9CAxhWJ6oVaByM60hUmP9mC93njCQXlg DUm9swJvc4113Ub/xAIxFMCk0q1OCk 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. x86 uses a single page guard, this is also sufficient for arm64 where we either do single word pops and pushes or unconstrained writes. Architectures which do not have this feature will define VM_SHADOW_STACK to VM_NONE and hence be unaffected. Suggested-by: Rick Edgecombe Acked-by: Lorenzo Stoakes Signed-off-by: Mark Brown --- mm/mmap.c | 14 ++++++++++++++ 1 file changed, 14 insertions(+) diff --git a/mm/mmap.c b/mm/mmap.c index b06ba847c96e..050c5ae2f80f 100644 --- a/mm/mmap.c +++ b/mm/mmap.c @@ -1753,6 +1753,18 @@ static unsigned long unmapped_area_topdown(struct vm_unmapped_area_info *info) return gap; } +/* + * Determine if the allocation needs to ensure that there is no + * existing mapping within it's guard gaps, for use as start_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 +1826,7 @@ 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 +1876,7 @@ 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); /*