linux-kernel - [tip:x86/urgent] x86/platform/UV: Use efi_runtime

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <tip-f331e766c4be33f4338574f3c9f7f77e98ab4571@git.kernel.org>
Date:   Fri, 15 Feb 2019 07:01:12 -0800
From:   tip-bot for Hedi Berriche <tipbot@...or.com>
To:     linux-tip-commits@...r.kernel.org
Cc:     bhsharma@...hat.com, dvhart@...radead.org, tglx@...utronix.de,
        hpa@...or.com, steve.wahl@....com, linux-kernel@...r.kernel.org,
        x86@...nel.org, sivanich@....com, ard.biesheuvel@...aro.org,
        linux-efi@...r.kernel.org, mingo@...nel.org, hedi.berriche@....com,
        mingo@...hat.com, mike.travis@....com, bp@...e.de, rja@....com,
        andy@...radead.org
Subject: [tip:x86/urgent] x86/platform/UV: Use efi_runtime_lock to serialise
 BIOS calls

Commit-ID:  f331e766c4be33f4338574f3c9f7f77e98ab4571
Gitweb:     https://git.kernel.org/tip/f331e766c4be33f4338574f3c9f7f77e98ab4571
Author:     Hedi Berriche <hedi.berriche@....com>
AuthorDate: Wed, 13 Feb 2019 19:34:13 +0000
Committer:  Borislav Petkov <bp@...e.de>
CommitDate: Fri, 15 Feb 2019 15:19:56 +0100

x86/platform/UV: Use efi_runtime_lock to serialise BIOS calls

Calls into UV firmware must be protected against concurrency, expose the
efi_runtime_lock to the UV platform, and use it to serialise UV BIOS
calls.

Signed-off-by: Hedi Berriche <hedi.berriche@....com>
Signed-off-by: Borislav Petkov <bp@...e.de>
Reviewed-by: Ard Biesheuvel <ard.biesheuvel@...aro.org>
Reviewed-by: Russ Anderson <rja@....com>
Reviewed-by: Dimitri Sivanich <sivanich@....com>
Reviewed-by: Mike Travis <mike.travis@....com>
Cc: Andy Shevchenko <andy@...radead.org>
Cc: Bhupesh Sharma <bhsharma@...hat.com>
Cc: Darren Hart <dvhart@...radead.org>
Cc: "H. Peter Anvin" <hpa@...or.com>
Cc: Ingo Molnar <mingo@...hat.com>
Cc: linux-efi <linux-efi@...r.kernel.org>
Cc: platform-driver-x86@...r.kernel.org
Cc: stable@...r.kernel.org # v4.9+
Cc: Steve Wahl <steve.wahl@....com>
Cc: Thomas Gleixner <tglx@...utronix.de>
Cc: x86-ml <x86@...nel.org>
Link: https://lkml.kernel.org/r/20190213193413.25560-5-hedi.berriche@hpe.com
---
 arch/x86/include/asm/uv/bios.h          |  8 +++++++-
 arch/x86/platform/uv/bios_uv.c          | 23 +++++++++++++++++++++--
 drivers/firmware/efi/runtime-wrappers.c |  7 +++++++
 3 files changed, 35 insertions(+), 3 deletions(-)

diff --git a/arch/x86/include/asm/uv/bios.h b/arch/x86/include/asm/uv/bios.h
index e652a7cc6186..3f697a9e3f59 100644
--- a/arch/x86/include/asm/uv/bios.h
+++ b/arch/x86/include/asm/uv/bios.h
@@ -48,7 +48,8 @@ enum {
 	BIOS_STATUS_SUCCESS		=  0,
 	BIOS_STATUS_UNIMPLEMENTED	= -ENOSYS,
 	BIOS_STATUS_EINVAL		= -EINVAL,
-	BIOS_STATUS_UNAVAIL		= -EBUSY
+	BIOS_STATUS_UNAVAIL		= -EBUSY,
+	BIOS_STATUS_ABORT		= -EINTR,
 };
 
 /* Address map parameters */
@@ -167,4 +168,9 @@ extern long system_serial_number;
 
 extern struct kobject *sgi_uv_kobj;	/* /sys/firmware/sgi_uv */
 
+/*
+ * EFI runtime lock; cf. firmware/efi/runtime-wrappers.c for details
+ */
+extern struct semaphore __efi_uv_runtime_lock;
+
 #endif /* _ASM_X86_UV_BIOS_H */
diff --git a/arch/x86/platform/uv/bios_uv.c b/arch/x86/platform/uv/bios_uv.c
index 4a6a5a26c582..eb33432f2f24 100644
--- a/arch/x86/platform/uv/bios_uv.c
+++ b/arch/x86/platform/uv/bios_uv.c
@@ -29,7 +29,8 @@
 
 struct uv_systab *uv_systab;
 
-s64 uv_bios_call(enum uv_bios_cmd which, u64 a1, u64 a2, u64 a3, u64 a4, u64 a5)
+static s64 __uv_bios_call(enum uv_bios_cmd which, u64 a1, u64 a2, u64 a3,
+			u64 a4, u64 a5)
 {
 	struct uv_systab *tab = uv_systab;
 	s64 ret;
@@ -51,6 +52,19 @@ s64 uv_bios_call(enum uv_bios_cmd which, u64 a1, u64 a2, u64 a3, u64 a4, u64 a5)
 
 	return ret;
 }
+
+s64 uv_bios_call(enum uv_bios_cmd which, u64 a1, u64 a2, u64 a3, u64 a4, u64 a5)
+{
+	s64 ret;
+
+	if (down_interruptible(&__efi_uv_runtime_lock))
+		return BIOS_STATUS_ABORT;
+
+	ret = __uv_bios_call(which, a1, a2, a3, a4, a5);
+	up(&__efi_uv_runtime_lock);
+
+	return ret;
+}
 EXPORT_SYMBOL_GPL(uv_bios_call);
 
 s64 uv_bios_call_irqsave(enum uv_bios_cmd which, u64 a1, u64 a2, u64 a3,
@@ -59,10 +73,15 @@ s64 uv_bios_call_irqsave(enum uv_bios_cmd which, u64 a1, u64 a2, u64 a3,
 	unsigned long bios_flags;
 	s64 ret;
 
+	if (down_interruptible(&__efi_uv_runtime_lock))
+		return BIOS_STATUS_ABORT;
+
 	local_irq_save(bios_flags);
-	ret = uv_bios_call(which, a1, a2, a3, a4, a5);
+	ret = __uv_bios_call(which, a1, a2, a3, a4, a5);
 	local_irq_restore(bios_flags);
 
+	up(&__efi_uv_runtime_lock);
+
 	return ret;
 }
 
diff --git a/drivers/firmware/efi/runtime-wrappers.c b/drivers/firmware/efi/runtime-wrappers.c
index 8903b9ccfc2b..e2abfdb5cee6 100644
--- a/drivers/firmware/efi/runtime-wrappers.c
+++ b/drivers/firmware/efi/runtime-wrappers.c
@@ -146,6 +146,13 @@ void efi_call_virt_check_flags(unsigned long flags, const char *call)
  */
 static DEFINE_SEMAPHORE(efi_runtime_lock);
 
+/*
+ * Expose the EFI runtime lock to the UV platform
+ */
+#ifdef CONFIG_X86_UV
+extern struct semaphore __efi_uv_runtime_lock __alias(efi_runtime_lock);
+#endif
+
 /*
  * Calls the appropriate efi_runtime_service() with the appropriate
  * arguments.