From mboxrd@z Thu Jan 1 00:00:00 1970 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 5A1DC1E5B72; Tue, 11 Feb 2025 01:32:28 +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=1739237548; cv=none; b=NagzCO2raVJ8QVexyQyR0zMhW7dWrbotgwS8y/pmJix07dYIgiuyp0jObJrdhJD6LikilbkGhEsC3cdWvAb9Pbqa4f6yMF3pSuSBDfjmhM0Wt9cADG2VTbFTJ4Hv6+/gHtYbmPUBeLicM8KktbbTEQ5SzwvR5qzq1YcHIk2Ym6I= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1739237548; c=relaxed/simple; bh=0ug/+8KuAHUsl07eDqakTaAjCd0t7b1nPlP7xiUXDxI=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=t1co4HeqH05OTw3dxcOeGK2LZc82LV23IdIdg5OcxbYFSpKsV4q30w594jyWVMexMm9wqV4qJAbDWgD76bOH2aROivBQX05cb1rPYu4tCnt8SgqV9OMCto6JNLtgmC3Pa/mTtiq6lxnDBaHDe45gOFHIKhDRjR1HIgSYh+jnomA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=RTu2tmLt; 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="RTu2tmLt" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 5E659C4CED1; Tue, 11 Feb 2025 01:32:26 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1739237548; bh=0ug/+8KuAHUsl07eDqakTaAjCd0t7b1nPlP7xiUXDxI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=RTu2tmLthjgRXNHKOsjQtA8iWVdZB6fqZY2UlXRJTsiC13g5nX19w4A/dB2fKOihZ pzXz6f+D8fQha+QaR6TxwC4MUmVDMAvuIebxPJtYxvsAjwKaMHM1j2lqrTilqckoX8 NPB7DalKaTticbOS9EmGsBsUGXShn7Ow5vLrgFaGiCcEKoHa95X5PmXzti04nGgZ3G p/8F9Z2nAfJIGClAd12Rxs+5HVOkeCjUb2G2O6tCIp1iecANQma2efgorGWNs9Gmw9 VK+LDjyXVc9Zvf+vZTVYzHEJqOD+VjBCRuzlR87SdQyD6+zq1jx2sFMc5NI9uJaUu5 8vtbETvGG8bnw== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: "Eric W. Biederman" , Richard Henderson , Arnd Bergmann , John Paul Adrian Glaubitz , Kees Cook , Sasha Levin , mattst88@gmail.com, paulmck@kernel.org, viro@zeniv.linux.org.uk, akpm@linux-foundation.org, brauner@kernel.org, Liam.Howlett@Oracle.com, rick.p.edgecombe@intel.com, broonie@kernel.org, linux-alpha@vger.kernel.org, linux-mm@kvack.org Subject: [PATCH AUTOSEL 6.1 10/11] alpha/elf: Fix misc/setarch test of util-linux by removing 32bit support Date: Mon, 10 Feb 2025 20:32:05 -0500 Message-Id: <20250211013206.4098522-10-sashal@kernel.org> X-Mailer: git-send-email 2.39.5 In-Reply-To: <20250211013206.4098522-1-sashal@kernel.org> References: <20250211013206.4098522-1-sashal@kernel.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore X-stable-base: Linux 6.1.128 Content-Transfer-Encoding: 8bit From: "Eric W. Biederman" [ Upstream commit b029628be267cba3c7684ec684749fe3e4372398 ] Richard Henderson writes[1]: > There was a Spec benchmark (I forget which) which was memory bound and ran > twice as fast with 32-bit pointers. > > I copied the idea from DEC to the ELF abi, but never did all the other work > to allow the toolchain to take advantage. > > Amusingly, a later Spec changed the benchmark data sets to not fit into a > 32-bit address space, specifically because of this. > > I expect one could delete the ELF bit and personality and no one would > notice. Not even the 10 remaining Alpha users. In [2] it was pointed out that parts of setarch weren't working properly on alpha because it has it's own SET_PERSONALITY implementation. In the discussion that followed Richard Henderson pointed out that the 32bit pointer support for alpha was never completed. Fix this by removing alpha's 32bit pointer support. As a bit of paranoia refuse to execute any alpha binaries that have the EF_ALPHA_32BIT flag set. Just in case someone somewhere has binaries that try to use alpha's 32bit pointer support. Link: https://lkml.kernel.org/r/CAFXwXrkgu=4Qn-v1PjnOR4SG0oUb9LSa0g6QXpBq4ttm52pJOQ@mail.gmail.com [1] Link: https://lkml.kernel.org/r/20250103140148.370368-1-glaubitz@physik.fu-berlin.de [2] Signed-off-by: Eric W. Biederman Reviewed-by: Richard Henderson Reviewed-by: Arnd Bergmann Reviewed-by: John Paul Adrian Glaubitz Tested-by: John Paul Adrian Glaubitz Link: https://lore.kernel.org/r/87y0zfs26i.fsf_-_@email.froward.int.ebiederm.org Signed-off-by: Kees Cook Signed-off-by: Sasha Levin --- arch/alpha/include/asm/elf.h | 6 +----- arch/alpha/include/asm/pgtable.h | 2 +- arch/alpha/include/asm/processor.h | 8 ++------ arch/alpha/kernel/osf_sys.c | 11 ++--------- 4 files changed, 6 insertions(+), 21 deletions(-) diff --git a/arch/alpha/include/asm/elf.h b/arch/alpha/include/asm/elf.h index 8049997fa372a..2039a8c8d5473 100644 --- a/arch/alpha/include/asm/elf.h +++ b/arch/alpha/include/asm/elf.h @@ -74,7 +74,7 @@ typedef elf_fpreg_t elf_fpregset_t[ELF_NFPREG]; /* * This is used to ensure we don't load something for the wrong architecture. */ -#define elf_check_arch(x) ((x)->e_machine == EM_ALPHA) +#define elf_check_arch(x) (((x)->e_machine == EM_ALPHA) && !((x)->e_flags & EF_ALPHA_32BIT)) /* * These are used to set parameters in the core dumps. @@ -145,10 +145,6 @@ extern int dump_elf_task_fp(elf_fpreg_t *dest, struct task_struct *task); : amask (AMASK_CIX) ? "ev6" : "ev67"); \ }) -#define SET_PERSONALITY(EX) \ - set_personality(((EX).e_flags & EF_ALPHA_32BIT) \ - ? PER_LINUX_32BIT : PER_LINUX) - extern int alpha_l1i_cacheshape; extern int alpha_l1d_cacheshape; extern int alpha_l2_cacheshape; diff --git a/arch/alpha/include/asm/pgtable.h b/arch/alpha/include/asm/pgtable.h index 9e45f6735d5d2..6fe4e9deeb5ef 100644 --- a/arch/alpha/include/asm/pgtable.h +++ b/arch/alpha/include/asm/pgtable.h @@ -322,7 +322,7 @@ extern inline pte_t mk_swap_pte(unsigned long type, unsigned long offset) extern void paging_init(void); -/* We have our own get_unmapped_area to cope with ADDR_LIMIT_32BIT. */ +/* We have our own get_unmapped_area */ #define HAVE_ARCH_UNMAPPED_AREA #endif /* _ALPHA_PGTABLE_H */ diff --git a/arch/alpha/include/asm/processor.h b/arch/alpha/include/asm/processor.h index 714abe494e5fd..916a2dd782c1a 100644 --- a/arch/alpha/include/asm/processor.h +++ b/arch/alpha/include/asm/processor.h @@ -8,23 +8,19 @@ #ifndef __ASM_ALPHA_PROCESSOR_H #define __ASM_ALPHA_PROCESSOR_H -#include /* for ADDR_LIMIT_32BIT */ - /* * We have a 42-bit user address space: 4TB user VM... */ #define TASK_SIZE (0x40000000000UL) -#define STACK_TOP \ - (current->personality & ADDR_LIMIT_32BIT ? 0x80000000 : 0x00120000000UL) +#define STACK_TOP (0x00120000000UL) #define STACK_TOP_MAX 0x00120000000UL /* This decides where the kernel will search for a free chunk of vm * space during mmap's. */ -#define TASK_UNMAPPED_BASE \ - ((current->personality & ADDR_LIMIT_32BIT) ? 0x40000000 : TASK_SIZE / 2) +#define TASK_UNMAPPED_BASE (TASK_SIZE / 2) /* This is dead. Everything has been moved to thread_info. */ struct thread_struct { }; diff --git a/arch/alpha/kernel/osf_sys.c b/arch/alpha/kernel/osf_sys.c index c54469b369cb6..03b70b6c92502 100644 --- a/arch/alpha/kernel/osf_sys.c +++ b/arch/alpha/kernel/osf_sys.c @@ -1213,8 +1213,7 @@ SYSCALL_DEFINE1(old_adjtimex, struct timex32 __user *, txc_p) return ret; } -/* Get an address range which is currently unmapped. Similar to the - generic version except that we know how to honor ADDR_LIMIT_32BIT. */ +/* Get an address range which is currently unmapped. */ static unsigned long arch_get_unmapped_area_1(unsigned long addr, unsigned long len, @@ -1236,13 +1235,7 @@ arch_get_unmapped_area(struct file *filp, unsigned long addr, unsigned long len, unsigned long pgoff, unsigned long flags) { - unsigned long limit; - - /* "32 bit" actually means 31 bit, since pointers sign extend. */ - if (current->personality & ADDR_LIMIT_32BIT) - limit = 0x80000000; - else - limit = TASK_SIZE; + unsigned long limit = TASK_SIZE; if (len > limit) return -ENOMEM; -- 2.39.5