From: Catalin Marinas <catalin.marinas@arm.com>
To: linux-arm-kernel@lists.infradead.org
Cc: linux-mm@kvack.org, linux-arch@vger.kernel.org,
Will Deacon <will@kernel.org>,
Dave P Martin <Dave.Martin@arm.com>,
Vincenzo Frascino <vincenzo.frascino@arm.com>,
Szabolcs Nagy <szabolcs.nagy@arm.com>,
Kevin Brodsky <kevin.brodsky@arm.com>,
Andrey Konovalov <andreyknvl@google.com>,
Peter Collingbourne <pcc@google.com>,
Andrew Morton <akpm@linux-foundation.org>
Subject: [PATCH v8 14/28] mm: Introduce arch_validate_flags()
Date: Mon, 24 Aug 2020 19:27:44 +0100 [thread overview]
Message-ID: <20200824182758.27267-15-catalin.marinas@arm.com> (raw)
In-Reply-To: <20200824182758.27267-1-catalin.marinas@arm.com>
Similarly to arch_validate_prot() called from do_mprotect_pkey(), an
architecture may need to sanity-check the new vm_flags.
Define a dummy function always returning true. In addition to
do_mprotect_pkey(), also invoke it from mmap_region() prior to updating
vma->vm_page_prot to allow the architecture code to veto potentially
inconsistent vm_flags.
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Andrew Morton <akpm@linux-foundation.org>
---
Notes:
v2:
- Some comments updated.
include/linux/mman.h | 13 +++++++++++++
mm/mmap.c | 9 +++++++++
mm/mprotect.c | 6 ++++++
3 files changed, 28 insertions(+)
diff --git a/include/linux/mman.h b/include/linux/mman.h
index 6fa15c9b12af..629cefc4ecba 100644
--- a/include/linux/mman.h
+++ b/include/linux/mman.h
@@ -108,6 +108,19 @@ static inline bool arch_validate_prot(unsigned long prot, unsigned long addr)
#define arch_validate_prot arch_validate_prot
#endif
+#ifndef arch_validate_flags
+/*
+ * This is called from mmap() and mprotect() with the updated vma->vm_flags.
+ *
+ * Returns true if the VM_* flags are valid.
+ */
+static inline bool arch_validate_flags(unsigned long flags)
+{
+ return true;
+}
+#define arch_validate_flags arch_validate_flags
+#endif
+
/*
* Optimisation macro. It is equivalent to:
* (x & bit1) ? bit2 : 0
diff --git a/mm/mmap.c b/mm/mmap.c
index 40248d84ad5f..eed30b096667 100644
--- a/mm/mmap.c
+++ b/mm/mmap.c
@@ -1812,6 +1812,15 @@ unsigned long mmap_region(struct file *file, unsigned long addr,
vma_set_anonymous(vma);
}
+ /* Allow architectures to sanity-check the vm_flags */
+ if (!arch_validate_flags(vma->vm_flags)) {
+ error = -EINVAL;
+ if (file)
+ goto unmap_and_free_vma;
+ else
+ goto free_vma;
+ }
+
vma_link(mm, vma, prev, rb_link, rb_parent);
/* Once vma denies write, undo our temporary denial count */
if (file) {
diff --git a/mm/mprotect.c b/mm/mprotect.c
index ce8b8a5eacbb..56c02beb6041 100644
--- a/mm/mprotect.c
+++ b/mm/mprotect.c
@@ -603,6 +603,12 @@ static int do_mprotect_pkey(unsigned long start, size_t len,
goto out;
}
+ /* Allow architectures to sanity-check the new flags */
+ if (!arch_validate_flags(newflags)) {
+ error = -EINVAL;
+ goto out;
+ }
+
error = security_file_mprotect(vma, reqprot, prot);
if (error)
goto out;
next prev parent reply other threads:[~2020-08-24 18:28 UTC|newest]
Thread overview: 37+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-08-24 18:27 [PATCH v8 00/28] arm64: Memory Tagging Extension user-space support Catalin Marinas
2020-08-24 18:27 ` [PATCH v8 01/28] arm64: mte: system register definitions Catalin Marinas
2020-08-24 18:27 ` [PATCH v8 02/28] arm64: mte: Use Normal Tagged attributes for the linear map Catalin Marinas
2020-08-24 18:27 ` [PATCH v8 03/28] arm64: mte: CPU feature detection and initial sysreg configuration Catalin Marinas
2020-08-25 8:53 ` Marc Zyngier
2020-08-25 10:54 ` Catalin Marinas
2020-08-25 13:53 ` Marc Zyngier
2020-08-26 17:08 ` Catalin Marinas
2020-09-04 10:10 ` Marc Zyngier
2020-08-26 15:24 ` Catalin Marinas
2020-08-24 18:27 ` [PATCH v8 04/28] arm64: mte: Add specific SIGSEGV codes Catalin Marinas
2020-08-24 18:27 ` [PATCH v8 05/28] arm64: mte: Handle synchronous and asynchronous tag check faults Catalin Marinas
2020-08-24 18:27 ` [PATCH v8 06/28] mm: Add PG_arch_2 page flag Catalin Marinas
2020-08-24 18:27 ` [PATCH v8 07/28] mm: Preserve the PG_arch_2 flag in __split_huge_page_tail() Catalin Marinas
2020-08-24 18:27 ` [PATCH v8 08/28] arm64: mte: Clear the tags when a page is mapped in user-space with PROT_MTE Catalin Marinas
2020-08-24 18:27 ` [PATCH v8 09/28] arm64: mte: Tags-aware copy_{user_,}highpage() implementations Catalin Marinas
2020-08-24 18:27 ` [PATCH v8 10/28] arm64: Avoid unnecessary clear_user_page() indirection Catalin Marinas
2020-08-24 18:27 ` [PATCH v8 11/28] arm64: mte: Tags-aware aware memcmp_pages() implementation Catalin Marinas
2020-08-24 18:27 ` [PATCH v8 12/28] mm: Introduce arch_calc_vm_flag_bits() Catalin Marinas
2020-08-24 18:27 ` [PATCH v8 13/28] arm64: mte: Add PROT_MTE support to mmap() and mprotect() Catalin Marinas
2020-08-24 18:27 ` Catalin Marinas [this message]
2020-08-24 18:27 ` [PATCH v8 15/28] arm64: mte: Validate the PROT_MTE request via arch_validate_flags() Catalin Marinas
2020-08-24 18:27 ` [PATCH v8 16/28] mm: Allow arm64 mmap(PROT_MTE) on RAM-based files Catalin Marinas
2020-08-24 18:27 ` [PATCH v8 17/28] arm64: mte: Allow user control of the tag check mode via prctl() Catalin Marinas
2020-08-24 18:27 ` [PATCH v8 18/28] arm64: mte: Allow user control of the generated random tags " Catalin Marinas
2020-08-24 18:27 ` [PATCH v8 19/28] arm64: mte: Restore the GCR_EL1 register after a suspend Catalin Marinas
2020-08-24 18:27 ` [PATCH v8 20/28] arm64: mte: Allow {set,get}_tagged_addr_ctrl() on non-current tasks Catalin Marinas
2020-08-24 18:27 ` [PATCH v8 21/28] arm64: mte: ptrace: Add PTRACE_{PEEK,POKE}MTETAGS support Catalin Marinas
2020-08-24 18:27 ` [PATCH v8 22/28] arm64: mte: ptrace: Add NT_ARM_TAGGED_ADDR_CTRL regset Catalin Marinas
2020-08-24 18:27 ` [PATCH v8 23/28] fs: Handle intra-page faults in copy_mount_options() Catalin Marinas
2020-08-24 18:27 ` [PATCH v8 24/28] mm: Add arch hooks for saving/restoring tags Catalin Marinas
2020-08-24 18:27 ` [PATCH v8 25/28] arm64: mte: Enable swap of tagged pages Catalin Marinas
2020-08-24 18:27 ` [PATCH v8 26/28] arm64: mte: Save tags when hibernating Catalin Marinas
2020-08-24 18:27 ` [PATCH v8 27/28] arm64: mte: Kconfig entry Catalin Marinas
2020-08-24 18:44 ` Randy Dunlap
2020-08-25 11:10 ` Catalin Marinas
2020-08-24 18:27 ` [PATCH v8 28/28] arm64: mte: Add Memory Tagging Extension documentation Catalin Marinas
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20200824182758.27267-15-catalin.marinas@arm.com \
--to=catalin.marinas@arm.com \
--cc=Dave.Martin@arm.com \
--cc=akpm@linux-foundation.org \
--cc=andreyknvl@google.com \
--cc=kevin.brodsky@arm.com \
--cc=linux-arch@vger.kernel.org \
--cc=linux-arm-kernel@lists.infradead.org \
--cc=linux-mm@kvack.org \
--cc=pcc@google.com \
--cc=szabolcs.nagy@arm.com \
--cc=vincenzo.frascino@arm.com \
--cc=will@kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).