From: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
To: linux-kernel@vger.kernel.org, x86@kernel.org, linux-sgx@vger.kernel.org
Cc: akpm@linux-foundation.org, dave.hansen@intel.com,
sean.j.christopherson@intel.com, nhorman@redhat.com,
npmccallum@redhat.com, serge.ayoun@intel.com,
shay.katz-zamir@intel.com, haitao.huang@intel.com,
andriy.shevchenko@linux.intel.com, tglx@linutronix.de,
kai.svahn@intel.com, bp@alien8.de, josh@joshtriplett.org,
luto@kernel.org, kai.huang@intel.com, rientjes@google.com,
cedric.xing@intel.com, puiterwijk@redhat.com,
Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Subject: [PATCH v23 19/24] x86/fault: Add helper function to sanitize error code
Date: Mon, 28 Oct 2019 23:03:19 +0200 [thread overview]
Message-ID: <20191028210324.12475-20-jarkko.sakkinen@linux.intel.com> (raw)
In-Reply-To: <20191028210324.12475-1-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.
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 b1f0060b263f..0e0842e941eb 100644
--- a/arch/x86/mm/fault.c
+++ b/arch/x86/mm/fault.c
@@ -681,6 +681,18 @@ 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)
{
@@ -737,6 +749,8 @@ 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. */
@@ -885,13 +899,7 @@ __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);
@@ -1008,6 +1016,8 @@ 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
--
2.20.1
next prev parent reply other threads:[~2019-10-28 21:06 UTC|newest]
Thread overview: 44+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-10-28 21:03 [PATCH v23 00/24] Intel SGX foundations Jarkko Sakkinen
2019-10-28 21:03 ` [PATCH v23 01/24] x86/sgx: Update MAINTAINERS Jarkko Sakkinen
2019-10-28 21:03 ` [PATCH v23 02/24] x86/cpufeatures: x86/msr: Add Intel SGX hardware bits Jarkko Sakkinen
2019-10-28 21:03 ` [PATCH v23 03/24] x86/cpufeatures: x86/msr: Intel SGX Launch Control " Jarkko Sakkinen
2019-10-28 21:03 ` [PATCH v23 04/24] x86/mm: x86/sgx: Signal SIGSEGV with PF_SGX Jarkko Sakkinen
2019-10-28 21:03 ` [PATCH v23 05/24] x86/sgx: Add SGX microarchitectural data structures Jarkko Sakkinen
2019-10-28 21:03 ` [PATCH v23 06/24] x86/sgx: Add wrappers for ENCLS leaf functions Jarkko Sakkinen
2019-10-28 21:03 ` [PATCH v23 07/24] x86/cpu/intel: Detect SGX supprt Jarkko Sakkinen
2019-10-28 21:03 ` [PATCH v23 08/24] x86/sgx: Enumerate and track EPC sections Jarkko Sakkinen
2019-10-28 21:03 ` [PATCH v23 09/24] x86/sgx: Add functions to allocate and free EPC pages Jarkko Sakkinen
2019-10-28 21:03 ` [PATCH v23 10/24] x86/sgx: Add sgx_einit() for wrapping ENCLS[EINIT] Jarkko Sakkinen
2019-10-28 21:03 ` [PATCH v23 11/24] mm: Introduce vm_ops->may_mprotect() Jarkko Sakkinen
2019-10-28 21:03 ` [PATCH v23 12/24] x86/sgx: Linux Enclave Driver Jarkko Sakkinen
2019-10-29 9:29 ` Jarkko Sakkinen
2019-10-30 9:30 ` Sean Christopherson
2019-10-31 21:12 ` Jarkko Sakkinen
2019-11-05 11:11 ` Jarkko Sakkinen
2019-11-08 8:20 ` Jarkko Sakkinen
2019-10-30 13:45 ` Stephen Smalley
2019-10-31 21:17 ` Jarkko Sakkinen
2019-11-01 13:16 ` Stephen Smalley
2019-11-01 13:28 ` Stephen Smalley
2019-11-01 15:32 ` Sean Christopherson
2019-11-01 17:16 ` Stephen Smalley
2019-11-08 8:05 ` Jarkko Sakkinen
2019-11-28 18:24 ` Greg KH
2019-12-06 20:38 ` Jarkko Sakkinen
2019-12-07 8:09 ` Greg KH
2019-12-09 19:57 ` Jarkko Sakkinen
2019-12-23 11:01 ` Jarkko Sakkinen
2019-10-28 21:03 ` [PATCH v23 13/24] selftests/x86: Recurse into subdirectories Jarkko Sakkinen
2019-10-28 21:03 ` [PATCH v23 14/24] selftests/x86: Add a selftest for SGX Jarkko Sakkinen
2019-10-28 21:03 ` [PATCH v23 15/24] x86/sgx: Add provisioning Jarkko Sakkinen
2019-10-28 21:03 ` [PATCH v23 16/24] x86/sgx: Add a page reclaimer Jarkko Sakkinen
2019-10-28 21:03 ` [PATCH v23 17/24] x86/sgx: ptrace() support for the SGX driver Jarkko Sakkinen
2019-10-28 21:03 ` [PATCH v23 18/24] x86/vdso: Add support for exception fixup in vDSO functions Jarkko Sakkinen
2019-10-28 21:03 ` Jarkko Sakkinen [this message]
2019-10-28 21:03 ` [PATCH v23 20/24] x86/traps: Attempt to fixup exceptions in vDSO before signaling Jarkko Sakkinen
2019-10-28 21:03 ` [PATCH v23 21/24] x86/vdso: Add __vdso_sgx_enter_enclave() to wrap SGX enclave transitions Jarkko Sakkinen
2019-10-28 21:03 ` [PATCH v23 22/24] selftests/x86: Add vDSO selftest for SGX Jarkko Sakkinen
2019-10-28 21:03 ` [PATCH v23 23/24] docs: x86/sgx: Document microarchitecture Jarkko Sakkinen
2019-10-28 21:03 ` [PATCH v23 24/24] docs: x86/sgx: Document kernel internals Jarkko Sakkinen
2019-11-21 15:08 ` [PATCH v23 00/24] Intel SGX foundations Nathaniel McCallum
2019-11-27 21:01 ` 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=20191028210324.12475-20-jarkko.sakkinen@linux.intel.com \
--to=jarkko.sakkinen@linux.intel.com \
--cc=akpm@linux-foundation.org \
--cc=andriy.shevchenko@linux.intel.com \
--cc=bp@alien8.de \
--cc=cedric.xing@intel.com \
--cc=dave.hansen@intel.com \
--cc=haitao.huang@intel.com \
--cc=josh@joshtriplett.org \
--cc=kai.huang@intel.com \
--cc=kai.svahn@intel.com \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-sgx@vger.kernel.org \
--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=serge.ayoun@intel.com \
--cc=shay.katz-zamir@intel.com \
--cc=tglx@linutronix.de \
--cc=x86@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).