From: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
To: linux-kernel@vger.kernel.org, x86@kernel.org, linux-sgx@vger.kernel.org
Cc: Sean Christopherson <sean.j.christopherson@intel.com>,
Jethro Beekman <jethro@fortanix.com>,
Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>,
akpm@linux-foundation.org, andriy.shevchenko@linux.intel.com,
asapek@google.com, bp@alien8.de, cedric.xing@intel.com,
chenalexchen@google.com, conradparker@google.com,
cyhanish@google.com, dave.hansen@intel.com,
haitao.huang@intel.com, josh@joshtriplett.org,
kai.huang@intel.com, kai.svahn@intel.com, kmoy@google.com,
ludloff@google.com, luto@kernel.org, nhorman@redhat.com,
npmccallum@redhat.com, puiterwijk@redhat.com,
rientjes@google.com, tglx@linutronix.de, yaozhangx@google.com
Subject: [PATCH v32 16/21] x86/fault: Add helper function to sanitize error code
Date: Mon, 1 Jun 2020 10:52:13 +0300 [thread overview]
Message-ID: <20200601075218.65618-17-jarkko.sakkinen@linux.intel.com> (raw)
In-Reply-To: <20200601075218.65618-1-jarkko.sakkinen@linux.intel.com>
From: Sean Christopherson <sean.j.christopherson@intel.com>
Add helper function to sanitize error code to prepare for vDSO exception
fixup, which will expose the error code to userspace and runs before
set_signal_archinfo(), i.e. suppresses the signal when fixup is successful.
Acked-by: Jethro Beekman <jethro@fortanix.com>
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
---
arch/x86/mm/fault.c | 24 +++++++++++++++++-------
1 file changed, 17 insertions(+), 7 deletions(-)
diff --git a/arch/x86/mm/fault.c b/arch/x86/mm/fault.c
index 16c53c874bb9..23666e34abbc 100644
--- a/arch/x86/mm/fault.c
+++ b/arch/x86/mm/fault.c
@@ -704,6 +704,18 @@ pgtable_bad(struct pt_regs *regs, unsigned long error_code,
oops_end(flags, regs, sig);
}
+static void sanitize_error_code(unsigned long address,
+ unsigned long *error_code)
+{
+ /*
+ * To avoid leaking information about the kernel page
+ * table layout, pretend that user-mode accesses to
+ * kernel addresses are always protection faults.
+ */
+ if (address >= TASK_SIZE_MAX)
+ *error_code |= X86_PF_PROT;
+}
+
static void set_signal_archinfo(unsigned long address,
unsigned long error_code)
{
@@ -760,6 +772,8 @@ no_context(struct pt_regs *regs, unsigned long error_code,
* faulting through the emulate_vsyscall() logic.
*/
if (current->thread.sig_on_uaccess_err && signal) {
+ sanitize_error_code(address, &error_code);
+
set_signal_archinfo(address, error_code);
/* XXX: hwpoison faults will set the wrong code. */
@@ -908,13 +922,7 @@ __bad_area_nosemaphore(struct pt_regs *regs, unsigned long error_code,
if (is_errata100(regs, address))
return;
- /*
- * To avoid leaking information about the kernel page table
- * layout, pretend that user-mode accesses to kernel addresses
- * are always protection faults.
- */
- if (address >= TASK_SIZE_MAX)
- error_code |= X86_PF_PROT;
+ sanitize_error_code(address, &error_code);
if (likely(show_unhandled_signals))
show_signal_msg(regs, error_code, address, tsk);
@@ -1031,6 +1039,8 @@ do_sigbus(struct pt_regs *regs, unsigned long error_code, unsigned long address,
if (is_prefetch(regs, error_code, address))
return;
+ sanitize_error_code(address, &error_code);
+
set_signal_archinfo(address, error_code);
#ifdef CONFIG_MEMORY_FAILURE
--
2.25.1
next prev parent reply other threads:[~2020-06-01 7:54 UTC|newest]
Thread overview: 35+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-06-01 7:51 [PATCH v32 00/21] Intel SGX foundations Jarkko Sakkinen
2020-06-01 7:51 ` [PATCH v32 01/21] x86/cpufeatures: x86/msr: Add Intel SGX hardware bits Jarkko Sakkinen
2020-06-01 7:51 ` [PATCH v32 02/21] x86/cpufeatures: x86/msr: Add Intel SGX Launch Control " Jarkko Sakkinen
2020-06-01 7:52 ` [PATCH v32 03/21] x86/mm: x86/sgx: Signal SIGSEGV with PF_SGX Jarkko Sakkinen
2020-06-01 7:52 ` [PATCH v32 04/21] x86/sgx: Add SGX microarchitectural data structures Jarkko Sakkinen
2020-06-01 7:52 ` [PATCH v32 05/21] x86/sgx: Add wrappers for ENCLS leaf functions Jarkko Sakkinen
2020-06-01 7:52 ` [PATCH v32 06/21] x86/cpu/intel: Detect SGX support Jarkko Sakkinen
2020-06-01 7:52 ` [PATCH v32 07/21] x86/cpu/intel: Add nosgx kernel parameter Jarkko Sakkinen
2020-06-01 7:52 ` [PATCH v32 08/21] x86/sgx: Initialize metadata for Enclave Page Cache (EPC) sections Jarkko Sakkinen
2020-06-01 15:15 ` Randy Dunlap
2020-06-15 20:07 ` Jarkko Sakkinen
2020-06-01 7:52 ` [PATCH v32 09/21] x86/sgx: Add __sgx_alloc_epc_page() and sgx_free_epc_page() Jarkko Sakkinen
2020-06-01 7:52 ` [PATCH v32 10/21] mm: Introduce vm_ops->may_mprotect() Jarkko Sakkinen
2020-06-01 7:52 ` [PATCH v32 11/21] x86/sgx: Linux Enclave Driver Jarkko Sakkinen
2020-06-01 7:52 ` [PATCH v32 12/21] x86/sgx: Add provisioning Jarkko Sakkinen
2020-06-05 20:09 ` Darren Kenny
2020-06-16 19:55 ` Jarkko Sakkinen
2020-06-16 20:03 ` Jarkko Sakkinen
2020-06-01 7:52 ` [PATCH v32 13/21] x86/sgx: Add a page reclaimer Jarkko Sakkinen
2020-06-01 7:52 ` [PATCH v32 14/21] x86/sgx: ptrace() support for the SGX driver Jarkko Sakkinen
2020-06-01 7:52 ` [PATCH v32 15/21] x86/vdso: Add support for exception fixup in vDSO functions Jarkko Sakkinen
2020-06-01 7:52 ` Jarkko Sakkinen [this message]
2020-06-01 7:52 ` [PATCH v32 17/21] x86/traps: Attempt to fixup exceptions in vDSO before signaling Jarkko Sakkinen
2020-06-01 7:52 ` [PATCH v32 18/21] x86/vdso: Implement a vDSO for Intel SGX enclave call Jarkko Sakkinen
2020-06-01 7:52 ` [PATCH v32 19/21] selftests/x86: Add a selftest for SGX Jarkko Sakkinen
2020-06-03 22:06 ` Sean Christopherson
2020-06-15 20:17 ` Jarkko Sakkinen
2020-06-01 7:52 ` [PATCH v32 20/21] docs: x86/sgx: Document SGX micro architecture and kernel internals Jarkko Sakkinen
2020-06-01 7:52 ` [PATCH v32 21/21] x86/sgx: Update MAINTAINERS Jarkko Sakkinen
2020-06-10 20:59 ` [PATCH v32 00/21] Intel SGX foundations Sean Christopherson
2020-06-16 20:09 ` Jarkko Sakkinen
2020-06-17 0:06 ` Sean Christopherson
2020-06-17 21:53 ` Jarkko Sakkinen
2020-06-15 12:13 ` Jethro Beekman
2020-06-16 20:11 ` Jarkko Sakkinen
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=20200601075218.65618-17-jarkko.sakkinen@linux.intel.com \
--to=jarkko.sakkinen@linux.intel.com \
--cc=akpm@linux-foundation.org \
--cc=andriy.shevchenko@linux.intel.com \
--cc=asapek@google.com \
--cc=bp@alien8.de \
--cc=cedric.xing@intel.com \
--cc=chenalexchen@google.com \
--cc=conradparker@google.com \
--cc=cyhanish@google.com \
--cc=dave.hansen@intel.com \
--cc=haitao.huang@intel.com \
--cc=jethro@fortanix.com \
--cc=josh@joshtriplett.org \
--cc=kai.huang@intel.com \
--cc=kai.svahn@intel.com \
--cc=kmoy@google.com \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-sgx@vger.kernel.org \
--cc=ludloff@google.com \
--cc=luto@kernel.org \
--cc=nhorman@redhat.com \
--cc=npmccallum@redhat.com \
--cc=puiterwijk@redhat.com \
--cc=rientjes@google.com \
--cc=sean.j.christopherson@intel.com \
--cc=tglx@linutronix.de \
--cc=x86@kernel.org \
--cc=yaozhangx@google.com \
/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).