This is a note to let you know that I've just added the patch titled
x86/retpoline: Fill RSB on context switch for affected CPUs
to the 4.4-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=sum…
The filename of the patch is:
x86-retpoline-fill-rsb-on-context-switch-for-affected-cpus.patch
and it can be found in the queue-4.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable(a)vger.kernel.org> know about it.
>From c995efd5a740d9cbafbf58bde4973e8b50b4d761 Mon Sep 17 00:00:00 2001
From: David Woodhouse <dwmw(a)amazon.co.uk>
Date: Fri, 12 Jan 2018 17:49:25 +0000
Subject: x86/retpoline: Fill RSB on context switch for affected CPUs
From: David Woodhouse <dwmw(a)amazon.co.uk>
commit c995efd5a740d9cbafbf58bde4973e8b50b4d761 upstream.
On context switch from a shallow call stack to a deeper one, as the CPU
does 'ret' up the deeper side it may encounter RSB entries (predictions for
where the 'ret' goes to) which were populated in userspace.
This is problematic if neither SMEP nor KPTI (the latter of which marks
userspace pages as NX for the kernel) are active, as malicious code in
userspace may then be executed speculatively.
Overwrite the CPU's return prediction stack with calls which are predicted
to return to an infinite loop, to "capture" speculation if this
happens. This is required both for retpoline, and also in conjunction with
IBRS for !SMEP && !KPTI.
On Skylake+ the problem is slightly different, and an *underflow* of the
RSB may cause errant branch predictions to occur. So there it's not so much
overwrite, as *filling* the RSB to attempt to prevent it getting
empty. This is only a partial solution for Skylake+ since there are many
other conditions which may result in the RSB becoming empty. The full
solution on Skylake+ is to use IBRS, which will prevent the problem even
when the RSB becomes empty. With IBRS, the RSB-stuffing will not be
required on context switch.
[ tglx: Added missing vendor check and slighty massaged comments and
changelog ]
[js] backport to 4.4 -- __switch_to_asm does not exist there, we
have to patch the switch_to macros for both x86_32 and x86_64.
Signed-off-by: David Woodhouse <dwmw(a)amazon.co.uk>
Signed-off-by: Thomas Gleixner <tglx(a)linutronix.de>
Acked-by: Arjan van de Ven <arjan(a)linux.intel.com>
Cc: gnomes(a)lxorguk.ukuu.org.uk
Cc: Rik van Riel <riel(a)redhat.com>
Cc: Andi Kleen <ak(a)linux.intel.com>
Cc: Josh Poimboeuf <jpoimboe(a)redhat.com>
Cc: thomas.lendacky(a)amd.com
Cc: Peter Zijlstra <peterz(a)infradead.org>
Cc: Linus Torvalds <torvalds(a)linux-foundation.org>
Cc: Jiri Kosina <jikos(a)kernel.org>
Cc: Andy Lutomirski <luto(a)amacapital.net>
Cc: Dave Hansen <dave.hansen(a)intel.com>
Cc: Kees Cook <keescook(a)google.com>
Cc: Tim Chen <tim.c.chen(a)linux.intel.com>
Cc: Greg Kroah-Hartman <gregkh(a)linux-foundation.org>
Cc: Paul Turner <pjt(a)google.com>
Link: https://lkml.kernel.org/r/1515779365-9032-1-git-send-email-dwmw@amazon.co.uk
Signed-off-by: Jiri Slaby <jslaby(a)suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
---
arch/x86/include/asm/cpufeature.h | 1 +
arch/x86/include/asm/switch_to.h | 38 ++++++++++++++++++++++++++++++++++++++
arch/x86/kernel/cpu/bugs.c | 36 ++++++++++++++++++++++++++++++++++++
3 files changed, 75 insertions(+)
--- a/arch/x86/include/asm/cpufeature.h
+++ b/arch/x86/include/asm/cpufeature.h
@@ -199,6 +199,7 @@
#define X86_FEATURE_HWP_EPP ( 7*32+13) /* Intel HWP_EPP */
#define X86_FEATURE_HWP_PKG_REQ ( 7*32+14) /* Intel HWP_PKG_REQ */
#define X86_FEATURE_INTEL_PT ( 7*32+15) /* Intel Processor Trace */
+#define X86_FEATURE_RSB_CTXSW ( 7*32+19) /* Fill RSB on context switches */
#define X86_FEATURE_RETPOLINE ( 7*32+29) /* Generic Retpoline mitigation for Spectre variant 2 */
#define X86_FEATURE_RETPOLINE_AMD ( 7*32+30) /* AMD Retpoline mitigation for Spectre variant 2 */
--- a/arch/x86/include/asm/switch_to.h
+++ b/arch/x86/include/asm/switch_to.h
@@ -1,6 +1,8 @@
#ifndef _ASM_X86_SWITCH_TO_H
#define _ASM_X86_SWITCH_TO_H
+#include <asm/nospec-branch.h>
+
struct task_struct; /* one of the stranger aspects of C forward declarations */
__visible struct task_struct *__switch_to(struct task_struct *prev,
struct task_struct *next);
@@ -24,6 +26,23 @@ void __switch_to_xtra(struct task_struct
#define __switch_canary_iparam
#endif /* CC_STACKPROTECTOR */
+#ifdef CONFIG_RETPOLINE
+ /*
+ * When switching from a shallower to a deeper call stack
+ * the RSB may either underflow or use entries populated
+ * with userspace addresses. On CPUs where those concerns
+ * exist, overwrite the RSB with entries which capture
+ * speculative execution to prevent attack.
+ */
+#define __retpoline_fill_return_buffer \
+ ALTERNATIVE("jmp 910f", \
+ __stringify(__FILL_RETURN_BUFFER(%%ebx, RSB_CLEAR_LOOPS, %%esp)),\
+ X86_FEATURE_RSB_CTXSW) \
+ "910:\n\t"
+#else
+#define __retpoline_fill_return_buffer
+#endif
+
/*
* Saving eflags is important. It switches not only IOPL between tasks,
* it also protects other tasks from NT leaking through sysenter etc.
@@ -46,6 +65,7 @@ do { \
"movl $1f,%[prev_ip]\n\t" /* save EIP */ \
"pushl %[next_ip]\n\t" /* restore EIP */ \
__switch_canary \
+ __retpoline_fill_return_buffer \
"jmp __switch_to\n" /* regparm call */ \
"1:\t" \
"popl %%ebp\n\t" /* restore EBP */ \
@@ -100,6 +120,23 @@ do { \
#define __switch_canary_iparam
#endif /* CC_STACKPROTECTOR */
+#ifdef CONFIG_RETPOLINE
+ /*
+ * When switching from a shallower to a deeper call stack
+ * the RSB may either underflow or use entries populated
+ * with userspace addresses. On CPUs where those concerns
+ * exist, overwrite the RSB with entries which capture
+ * speculative execution to prevent attack.
+ */
+#define __retpoline_fill_return_buffer \
+ ALTERNATIVE("jmp 910f", \
+ __stringify(__FILL_RETURN_BUFFER(%%r12, RSB_CLEAR_LOOPS, %%rsp)),\
+ X86_FEATURE_RSB_CTXSW) \
+ "910:\n\t"
+#else
+#define __retpoline_fill_return_buffer
+#endif
+
/*
* There is no need to save or restore flags, because flags are always
* clean in kernel mode, with the possible exception of IOPL. Kernel IOPL
@@ -112,6 +149,7 @@ do { \
"call __switch_to\n\t" \
"movq "__percpu_arg([current_task])",%%rsi\n\t" \
__switch_canary \
+ __retpoline_fill_return_buffer \
"movq %P[thread_info](%%rsi),%%r8\n\t" \
"movq %%rax,%%rdi\n\t" \
"testl %[_tif_fork],%P[ti_flags](%%r8)\n\t" \
--- a/arch/x86/kernel/cpu/bugs.c
+++ b/arch/x86/kernel/cpu/bugs.c
@@ -22,6 +22,7 @@
#include <asm/alternative.h>
#include <asm/pgtable.h>
#include <asm/cacheflush.h>
+#include <asm/intel-family.h>
static void __init spectre_v2_select_mitigation(void);
@@ -154,6 +155,23 @@ disable:
return SPECTRE_V2_CMD_NONE;
}
+/* Check for Skylake-like CPUs (for RSB handling) */
+static bool __init is_skylake_era(void)
+{
+ if (boot_cpu_data.x86_vendor == X86_VENDOR_INTEL &&
+ boot_cpu_data.x86 == 6) {
+ switch (boot_cpu_data.x86_model) {
+ case INTEL_FAM6_SKYLAKE_MOBILE:
+ case INTEL_FAM6_SKYLAKE_DESKTOP:
+ case INTEL_FAM6_SKYLAKE_X:
+ case INTEL_FAM6_KABYLAKE_MOBILE:
+ case INTEL_FAM6_KABYLAKE_DESKTOP:
+ return true;
+ }
+ }
+ return false;
+}
+
static void __init spectre_v2_select_mitigation(void)
{
enum spectre_v2_mitigation_cmd cmd = spectre_v2_parse_cmdline();
@@ -212,6 +230,24 @@ retpoline_auto:
spectre_v2_enabled = mode;
pr_info("%s\n", spectre_v2_strings[mode]);
+
+ /*
+ * If neither SMEP or KPTI are available, there is a risk of
+ * hitting userspace addresses in the RSB after a context switch
+ * from a shallow call stack to a deeper one. To prevent this fill
+ * the entire RSB, even when using IBRS.
+ *
+ * Skylake era CPUs have a separate issue with *underflow* of the
+ * RSB, when they will predict 'ret' targets from the generic BTB.
+ * The proper mitigation for this is IBRS. If IBRS is not supported
+ * or deactivated in favour of retpolines the RSB fill on context
+ * switch is required.
+ */
+ if ((!boot_cpu_has(X86_FEATURE_KAISER) &&
+ !boot_cpu_has(X86_FEATURE_SMEP)) || is_skylake_era()) {
+ setup_force_cpu_cap(X86_FEATURE_RSB_CTXSW);
+ pr_info("Filling RSB on context switch\n");
+ }
}
#undef pr_fmt
Patches currently in stable-queue which might be from dwmw(a)amazon.co.uk are
queue-4.4/x86-retpoline-fill-rsb-on-context-switch-for-affected-cpus.patch
This is a note to let you know that I've just added the patch titled
x86/cpu/intel: Introduce macros for Intel family numbers
to the 4.4-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=sum…
The filename of the patch is:
x86-cpu-intel-introduce-macros-for-intel-family-numbers.patch
and it can be found in the queue-4.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable(a)vger.kernel.org> know about it.
>From 970442c599b22ccd644ebfe94d1d303bf6f87c05 Mon Sep 17 00:00:00 2001
From: Dave Hansen <dave(a)sr71.net>
Date: Thu, 2 Jun 2016 17:19:27 -0700
Subject: x86/cpu/intel: Introduce macros for Intel family numbers
From: Dave Hansen <dave(a)sr71.net>
commit 970442c599b22ccd644ebfe94d1d303bf6f87c05 upstream.
Problem:
We have a boatload of open-coded family-6 model numbers. Half of
them have these model numbers in hex and the other half in
decimal. This makes grepping for them tons of fun, if you were
to try.
Solution:
Consolidate all the magic numbers. Put all the definitions in
one header.
The names here are closely derived from the comments describing
the models from arch/x86/events/intel/core.c. We could easily
make them shorter by doing things like s/SANDYBRIDGE/SNB/, but
they seemed fine even with the longer versions to me.
Do not take any of these names too literally, like "DESKTOP"
or "MOBILE". These are all colloquial names and not precise
descriptions of everywhere a given model will show up.
Signed-off-by: Dave Hansen <dave.hansen(a)linux.intel.com>
Cc: Adrian Hunter <adrian.hunter(a)intel.com>
Cc: Andy Lutomirski <luto(a)amacapital.net>
Cc: Andy Lutomirski <luto(a)kernel.org>
Cc: Borislav Petkov <bp(a)alien8.de>
Cc: Brian Gerst <brgerst(a)gmail.com>
Cc: Darren Hart <dvhart(a)infradead.org>
Cc: Dave Hansen <dave(a)sr71.net>
Cc: Denys Vlasenko <dvlasenk(a)redhat.com>
Cc: Doug Thompson <dougthompson(a)xmission.com>
Cc: Eduardo Valentin <edubezval(a)gmail.com>
Cc: H. Peter Anvin <hpa(a)zytor.com>
Cc: Jacob Pan <jacob.jun.pan(a)linux.intel.com>
Cc: Kan Liang <kan.liang(a)intel.com>
Cc: Len Brown <lenb(a)kernel.org>
Cc: Linus Torvalds <torvalds(a)linux-foundation.org>
Cc: Mauro Carvalho Chehab <mchehab(a)osg.samsung.com>
Cc: Peter Zijlstra <peterz(a)infradead.org>
Cc: Rafael J. Wysocki <rafael.j.wysocki(a)intel.com>
Cc: Rajneesh Bhardwaj <rajneesh.bhardwaj(a)intel.com>
Cc: Souvik Kumar Chakravarty <souvik.k.chakravarty(a)intel.com>
Cc: Srinivas Pandruvada <srinivas.pandruvada(a)linux.intel.com>
Cc: Stephane Eranian <eranian(a)google.com>
Cc: Thomas Gleixner <tglx(a)linutronix.de>
Cc: Tony Luck <tony.luck(a)intel.com>
Cc: Ulf Hansson <ulf.hansson(a)linaro.org>
Cc: Viresh Kumar <viresh.kumar(a)linaro.org>
Cc: Vishwanath Somayaji <vishwanath.somayaji(a)intel.com>
Cc: Zhang Rui <rui.zhang(a)intel.com>
Cc: jacob.jun.pan(a)intel.com
Cc: linux-acpi(a)vger.kernel.org
Cc: linux-edac(a)vger.kernel.org
Cc: linux-mmc(a)vger.kernel.org
Cc: linux-pm(a)vger.kernel.org
Cc: platform-driver-x86(a)vger.kernel.org
Link: http://lkml.kernel.org/r/20160603001927.F2A7D828@viggo.jf.intel.com
Signed-off-by: Ingo Molnar <mingo(a)kernel.org>
Cc: Jiri Slaby <jslaby(a)suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
---
arch/x86/include/asm/intel-family.h | 68 ++++++++++++++++++++++++++++++++++++
1 file changed, 68 insertions(+)
--- /dev/null
+++ b/arch/x86/include/asm/intel-family.h
@@ -0,0 +1,68 @@
+#ifndef _ASM_X86_INTEL_FAMILY_H
+#define _ASM_X86_INTEL_FAMILY_H
+
+/*
+ * "Big Core" Processors (Branded as Core, Xeon, etc...)
+ *
+ * The "_X" parts are generally the EP and EX Xeons, or the
+ * "Extreme" ones, like Broadwell-E.
+ *
+ * Things ending in "2" are usually because we have no better
+ * name for them. There's no processor called "WESTMERE2".
+ */
+
+#define INTEL_FAM6_CORE_YONAH 0x0E
+#define INTEL_FAM6_CORE2_MEROM 0x0F
+#define INTEL_FAM6_CORE2_MEROM_L 0x16
+#define INTEL_FAM6_CORE2_PENRYN 0x17
+#define INTEL_FAM6_CORE2_DUNNINGTON 0x1D
+
+#define INTEL_FAM6_NEHALEM 0x1E
+#define INTEL_FAM6_NEHALEM_EP 0x1A
+#define INTEL_FAM6_NEHALEM_EX 0x2E
+#define INTEL_FAM6_WESTMERE 0x25
+#define INTEL_FAM6_WESTMERE2 0x1F
+#define INTEL_FAM6_WESTMERE_EP 0x2C
+#define INTEL_FAM6_WESTMERE_EX 0x2F
+
+#define INTEL_FAM6_SANDYBRIDGE 0x2A
+#define INTEL_FAM6_SANDYBRIDGE_X 0x2D
+#define INTEL_FAM6_IVYBRIDGE 0x3A
+#define INTEL_FAM6_IVYBRIDGE_X 0x3E
+
+#define INTEL_FAM6_HASWELL_CORE 0x3C
+#define INTEL_FAM6_HASWELL_X 0x3F
+#define INTEL_FAM6_HASWELL_ULT 0x45
+#define INTEL_FAM6_HASWELL_GT3E 0x46
+
+#define INTEL_FAM6_BROADWELL_CORE 0x3D
+#define INTEL_FAM6_BROADWELL_XEON_D 0x56
+#define INTEL_FAM6_BROADWELL_GT3E 0x47
+#define INTEL_FAM6_BROADWELL_X 0x4F
+
+#define INTEL_FAM6_SKYLAKE_MOBILE 0x4E
+#define INTEL_FAM6_SKYLAKE_DESKTOP 0x5E
+#define INTEL_FAM6_SKYLAKE_X 0x55
+#define INTEL_FAM6_KABYLAKE_MOBILE 0x8E
+#define INTEL_FAM6_KABYLAKE_DESKTOP 0x9E
+
+/* "Small Core" Processors (Atom) */
+
+#define INTEL_FAM6_ATOM_PINEVIEW 0x1C
+#define INTEL_FAM6_ATOM_LINCROFT 0x26
+#define INTEL_FAM6_ATOM_PENWELL 0x27
+#define INTEL_FAM6_ATOM_CLOVERVIEW 0x35
+#define INTEL_FAM6_ATOM_CEDARVIEW 0x36
+#define INTEL_FAM6_ATOM_SILVERMONT1 0x37 /* BayTrail/BYT / Valleyview */
+#define INTEL_FAM6_ATOM_SILVERMONT2 0x4D /* Avaton/Rangely */
+#define INTEL_FAM6_ATOM_AIRMONT 0x4C /* CherryTrail / Braswell */
+#define INTEL_FAM6_ATOM_MERRIFIELD1 0x4A /* Tangier */
+#define INTEL_FAM6_ATOM_MERRIFIELD2 0x5A /* Annidale */
+#define INTEL_FAM6_ATOM_GOLDMONT 0x5C
+#define INTEL_FAM6_ATOM_DENVERTON 0x5F /* Goldmont Microserver */
+
+/* Xeon Phi */
+
+#define INTEL_FAM6_XEON_PHI_KNL 0x57 /* Knights Landing */
+
+#endif /* _ASM_X86_INTEL_FAMILY_H */
Patches currently in stable-queue which might be from dave(a)sr71.net are
queue-4.4/x86-cpu-intel-introduce-macros-for-intel-family-numbers.patch
The backport of commit b94b73733171 ("x86/microcode/intel: Extend BDW
late-loading with a revision check") to 4.4-stable deleted a "return true"
statement. This bug is not present upstream or other stable branches.
Signed-off-by: Ben Hutchings <ben.hutchings(a)codethink.co.uk>
---
arch/x86/kernel/cpu/microcode/intel.c | 1 +
1 file changed, 1 insertion(+)
diff --git a/arch/x86/kernel/cpu/microcode/intel.c b/arch/x86/kernel/cpu/microcode/intel.c
index b428a8174be1..ee011bd7934d 100644
--- a/arch/x86/kernel/cpu/microcode/intel.c
+++ b/arch/x86/kernel/cpu/microcode/intel.c
@@ -1005,6 +1005,7 @@ static bool is_blacklisted(unsigned int cpu)
c->microcode < 0x0b000021) {
pr_err_once("Erratum BDF90: late loading with revision < 0x0b000021 (0x%x) disabled.\n", c->microcode);
pr_err_once("Please consider either early loading through initrd/built-in or a potential BIOS update.\n");
+ return true;
}
return false;
--
2.15.0.rc0
The patch below does not apply to the 4.4-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable(a)vger.kernel.org>.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
>From c995efd5a740d9cbafbf58bde4973e8b50b4d761 Mon Sep 17 00:00:00 2001
From: David Woodhouse <dwmw(a)amazon.co.uk>
Date: Fri, 12 Jan 2018 17:49:25 +0000
Subject: [PATCH] x86/retpoline: Fill RSB on context switch for affected CPUs
On context switch from a shallow call stack to a deeper one, as the CPU
does 'ret' up the deeper side it may encounter RSB entries (predictions for
where the 'ret' goes to) which were populated in userspace.
This is problematic if neither SMEP nor KPTI (the latter of which marks
userspace pages as NX for the kernel) are active, as malicious code in
userspace may then be executed speculatively.
Overwrite the CPU's return prediction stack with calls which are predicted
to return to an infinite loop, to "capture" speculation if this
happens. This is required both for retpoline, and also in conjunction with
IBRS for !SMEP && !KPTI.
On Skylake+ the problem is slightly different, and an *underflow* of the
RSB may cause errant branch predictions to occur. So there it's not so much
overwrite, as *filling* the RSB to attempt to prevent it getting
empty. This is only a partial solution for Skylake+ since there are many
other conditions which may result in the RSB becoming empty. The full
solution on Skylake+ is to use IBRS, which will prevent the problem even
when the RSB becomes empty. With IBRS, the RSB-stuffing will not be
required on context switch.
[ tglx: Added missing vendor check and slighty massaged comments and
changelog ]
Signed-off-by: David Woodhouse <dwmw(a)amazon.co.uk>
Signed-off-by: Thomas Gleixner <tglx(a)linutronix.de>
Acked-by: Arjan van de Ven <arjan(a)linux.intel.com>
Cc: gnomes(a)lxorguk.ukuu.org.uk
Cc: Rik van Riel <riel(a)redhat.com>
Cc: Andi Kleen <ak(a)linux.intel.com>
Cc: Josh Poimboeuf <jpoimboe(a)redhat.com>
Cc: thomas.lendacky(a)amd.com
Cc: Peter Zijlstra <peterz(a)infradead.org>
Cc: Linus Torvalds <torvalds(a)linux-foundation.org>
Cc: Jiri Kosina <jikos(a)kernel.org>
Cc: Andy Lutomirski <luto(a)amacapital.net>
Cc: Dave Hansen <dave.hansen(a)intel.com>
Cc: Kees Cook <keescook(a)google.com>
Cc: Tim Chen <tim.c.chen(a)linux.intel.com>
Cc: Greg Kroah-Hartman <gregkh(a)linux-foundation.org>
Cc: Paul Turner <pjt(a)google.com>
Link: https://lkml.kernel.org/r/1515779365-9032-1-git-send-email-dwmw@amazon.co.uk
diff --git a/arch/x86/entry/entry_32.S b/arch/x86/entry/entry_32.S
index a1f28a54f23a..60c4c342316c 100644
--- a/arch/x86/entry/entry_32.S
+++ b/arch/x86/entry/entry_32.S
@@ -244,6 +244,17 @@ ENTRY(__switch_to_asm)
movl %ebx, PER_CPU_VAR(stack_canary)+stack_canary_offset
#endif
+#ifdef CONFIG_RETPOLINE
+ /*
+ * When switching from a shallower to a deeper call stack
+ * the RSB may either underflow or use entries populated
+ * with userspace addresses. On CPUs where those concerns
+ * exist, overwrite the RSB with entries which capture
+ * speculative execution to prevent attack.
+ */
+ FILL_RETURN_BUFFER %ebx, RSB_CLEAR_LOOPS, X86_FEATURE_RSB_CTXSW
+#endif
+
/* restore callee-saved registers */
popl %esi
popl %edi
diff --git a/arch/x86/entry/entry_64.S b/arch/x86/entry/entry_64.S
index 59874bc1aed2..d54a0ede61d1 100644
--- a/arch/x86/entry/entry_64.S
+++ b/arch/x86/entry/entry_64.S
@@ -487,6 +487,17 @@ ENTRY(__switch_to_asm)
movq %rbx, PER_CPU_VAR(irq_stack_union)+stack_canary_offset
#endif
+#ifdef CONFIG_RETPOLINE
+ /*
+ * When switching from a shallower to a deeper call stack
+ * the RSB may either underflow or use entries populated
+ * with userspace addresses. On CPUs where those concerns
+ * exist, overwrite the RSB with entries which capture
+ * speculative execution to prevent attack.
+ */
+ FILL_RETURN_BUFFER %r12, RSB_CLEAR_LOOPS, X86_FEATURE_RSB_CTXSW
+#endif
+
/* restore callee-saved registers */
popq %r15
popq %r14
diff --git a/arch/x86/include/asm/cpufeatures.h b/arch/x86/include/asm/cpufeatures.h
index f275447862f4..aa09559b2c0b 100644
--- a/arch/x86/include/asm/cpufeatures.h
+++ b/arch/x86/include/asm/cpufeatures.h
@@ -211,6 +211,7 @@
#define X86_FEATURE_AVX512_4FMAPS ( 7*32+17) /* AVX-512 Multiply Accumulation Single precision */
#define X86_FEATURE_MBA ( 7*32+18) /* Memory Bandwidth Allocation */
+#define X86_FEATURE_RSB_CTXSW ( 7*32+19) /* Fill RSB on context switches */
/* Virtualization flags: Linux defined, word 8 */
#define X86_FEATURE_TPR_SHADOW ( 8*32+ 0) /* Intel TPR Shadow */
diff --git a/arch/x86/kernel/cpu/bugs.c b/arch/x86/kernel/cpu/bugs.c
index e4dc26185aa7..390b3dc3d438 100644
--- a/arch/x86/kernel/cpu/bugs.c
+++ b/arch/x86/kernel/cpu/bugs.c
@@ -23,6 +23,7 @@
#include <asm/alternative.h>
#include <asm/pgtable.h>
#include <asm/set_memory.h>
+#include <asm/intel-family.h>
static void __init spectre_v2_select_mitigation(void);
@@ -155,6 +156,23 @@ static enum spectre_v2_mitigation_cmd __init spectre_v2_parse_cmdline(void)
return SPECTRE_V2_CMD_NONE;
}
+/* Check for Skylake-like CPUs (for RSB handling) */
+static bool __init is_skylake_era(void)
+{
+ if (boot_cpu_data.x86_vendor == X86_VENDOR_INTEL &&
+ boot_cpu_data.x86 == 6) {
+ switch (boot_cpu_data.x86_model) {
+ case INTEL_FAM6_SKYLAKE_MOBILE:
+ case INTEL_FAM6_SKYLAKE_DESKTOP:
+ case INTEL_FAM6_SKYLAKE_X:
+ case INTEL_FAM6_KABYLAKE_MOBILE:
+ case INTEL_FAM6_KABYLAKE_DESKTOP:
+ return true;
+ }
+ }
+ return false;
+}
+
static void __init spectre_v2_select_mitigation(void)
{
enum spectre_v2_mitigation_cmd cmd = spectre_v2_parse_cmdline();
@@ -213,6 +231,24 @@ static void __init spectre_v2_select_mitigation(void)
spectre_v2_enabled = mode;
pr_info("%s\n", spectre_v2_strings[mode]);
+
+ /*
+ * If neither SMEP or KPTI are available, there is a risk of
+ * hitting userspace addresses in the RSB after a context switch
+ * from a shallow call stack to a deeper one. To prevent this fill
+ * the entire RSB, even when using IBRS.
+ *
+ * Skylake era CPUs have a separate issue with *underflow* of the
+ * RSB, when they will predict 'ret' targets from the generic BTB.
+ * The proper mitigation for this is IBRS. If IBRS is not supported
+ * or deactivated in favour of retpolines the RSB fill on context
+ * switch is required.
+ */
+ if ((!boot_cpu_has(X86_FEATURE_PTI) &&
+ !boot_cpu_has(X86_FEATURE_SMEP)) || is_skylake_era()) {
+ setup_force_cpu_cap(X86_FEATURE_RSB_CTXSW);
+ pr_info("Filling RSB on context switch\n");
+ }
}
#undef pr_fmt
This is a note to let you know that I've just added the patch titled
usbip: prevent vhci_hcd driver from leaking a socket pointer address
to the 4.9-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=sum…
The filename of the patch is:
usbip-prevent-vhci_hcd-driver-from-leaking-a-socket-pointer-address.patch
and it can be found in the queue-4.9 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable(a)vger.kernel.org> know about it.
>From 2f2d0088eb93db5c649d2a5e34a3800a8a935fc5 Mon Sep 17 00:00:00 2001
From: Shuah Khan <shuahkh(a)osg.samsung.com>
Date: Thu, 7 Dec 2017 14:16:49 -0700
Subject: usbip: prevent vhci_hcd driver from leaking a socket pointer address
From: Shuah Khan <shuahkh(a)osg.samsung.com>
commit 2f2d0088eb93db5c649d2a5e34a3800a8a935fc5 upstream.
When a client has a USB device attached over IP, the vhci_hcd driver is
locally leaking a socket pointer address via the
/sys/devices/platform/vhci_hcd/status file (world-readable) and in debug
output when "usbip --debug port" is run.
Fix it to not leak. The socket pointer address is not used at the moment
and it was made visible as a convenient way to find IP address from socket
pointer address by looking up /proc/net/{tcp,tcp6}.
As this opens a security hole, the fix replaces socket pointer address with
sockfd.
Reported-by: Secunia Research <vuln(a)secunia.com>
Signed-off-by: Shuah Khan <shuahkh(a)osg.samsung.com>
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
---
drivers/usb/usbip/usbip_common.h | 1 +
drivers/usb/usbip/vhci_sysfs.c | 25 +++++++++++++++----------
tools/usb/usbip/libsrc/vhci_driver.c | 8 ++++----
3 files changed, 20 insertions(+), 14 deletions(-)
--- a/drivers/usb/usbip/usbip_common.h
+++ b/drivers/usb/usbip/usbip_common.h
@@ -271,6 +271,7 @@ struct usbip_device {
/* lock for status */
spinlock_t lock;
+ int sockfd;
struct socket *tcp_socket;
struct task_struct *tcp_rx;
--- a/drivers/usb/usbip/vhci_sysfs.c
+++ b/drivers/usb/usbip/vhci_sysfs.c
@@ -49,13 +49,17 @@ static ssize_t status_show_vhci(int pdev
/*
* output example:
- * port sta spd dev socket local_busid
- * 0000 004 000 00000000 c5a7bb80 1-2.3
- * 0001 004 000 00000000 d8cee980 2-3.4
+ * port sta spd dev sockfd local_busid
+ * 0000 004 000 00000000 000003 1-2.3
+ * 0001 004 000 00000000 000004 2-3.4
*
- * IP address can be retrieved from a socket pointer address by looking
- * up /proc/net/{tcp,tcp6}. Also, a userland program may remember a
- * port number and its peer IP address.
+ * Output includes socket fd instead of socket pointer address to
+ * avoid leaking kernel memory address in:
+ * /sys/devices/platform/vhci_hcd.0/status and in debug output.
+ * The socket pointer address is not used at the moment and it was
+ * made visible as a convenient way to find IP address from socket
+ * pointer address by looking up /proc/net/{tcp,tcp6}. As this opens
+ * a security hole, the change is made to use sockfd instead.
*/
for (i = 0; i < VHCI_HC_PORTS; i++) {
struct vhci_device *vdev = &vhci->vdev[i];
@@ -68,13 +72,13 @@ static ssize_t status_show_vhci(int pdev
if (vdev->ud.status == VDEV_ST_USED) {
out += sprintf(out, "%03u %08x ",
vdev->speed, vdev->devid);
- out += sprintf(out, "%16p %s",
- vdev->ud.tcp_socket,
+ out += sprintf(out, "%06u %s",
+ vdev->ud.sockfd,
dev_name(&vdev->udev->dev));
} else {
out += sprintf(out, "000 00000000 ");
- out += sprintf(out, "0000000000000000 0-0");
+ out += sprintf(out, "000000 0-0");
}
out += sprintf(out, "\n");
@@ -125,7 +129,7 @@ static ssize_t status_show(struct device
int pdev_nr;
out += sprintf(out,
- "port sta spd dev socket local_busid\n");
+ "port sta spd dev sockfd local_busid\n");
pdev_nr = status_name_to_id(attr->attr.name);
if (pdev_nr < 0)
@@ -324,6 +328,7 @@ static ssize_t store_attach(struct devic
vdev->devid = devid;
vdev->speed = speed;
+ vdev->ud.sockfd = sockfd;
vdev->ud.tcp_socket = socket;
vdev->ud.status = VDEV_ST_NOTASSIGNED;
--- a/tools/usb/usbip/libsrc/vhci_driver.c
+++ b/tools/usb/usbip/libsrc/vhci_driver.c
@@ -55,12 +55,12 @@ static int parse_status(const char *valu
while (*c != '\0') {
int port, status, speed, devid;
- unsigned long socket;
+ int sockfd;
char lbusid[SYSFS_BUS_ID_SIZE];
- ret = sscanf(c, "%d %d %d %x %lx %31s\n",
+ ret = sscanf(c, "%d %d %d %x %u %31s\n",
&port, &status, &speed,
- &devid, &socket, lbusid);
+ &devid, &sockfd, lbusid);
if (ret < 5) {
dbg("sscanf failed: %d", ret);
@@ -69,7 +69,7 @@ static int parse_status(const char *valu
dbg("port %d status %d speed %d devid %x",
port, status, speed, devid);
- dbg("socket %lx lbusid %s", socket, lbusid);
+ dbg("sockfd %u lbusid %s", sockfd, lbusid);
/* if a device is connected, look at it */
Patches currently in stable-queue which might be from shuahkh(a)osg.samsung.com are
queue-4.9/usbip-fix-potential-format-overflow-in-userspace-tools.patch
queue-4.9/usbip-fix-implicit-fallthrough-warning.patch
queue-4.9/usbip-prevent-vhci_hcd-driver-from-leaking-a-socket-pointer-address.patch
This is a note to let you know that I've just added the patch titled
usbip: Fix potential format overflow in userspace tools
to the 4.9-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=sum…
The filename of the patch is:
usbip-fix-potential-format-overflow-in-userspace-tools.patch
and it can be found in the queue-4.9 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable(a)vger.kernel.org> know about it.
>From e5dfa3f902b9a642ae8c6997d57d7c41e384a90b Mon Sep 17 00:00:00 2001
From: Jonathan Dieter <jdieter(a)lesbg.com>
Date: Mon, 27 Feb 2017 10:31:03 +0200
Subject: usbip: Fix potential format overflow in userspace tools
From: Jonathan Dieter <jdieter(a)lesbg.com>
commit e5dfa3f902b9a642ae8c6997d57d7c41e384a90b upstream.
The usbip userspace tools call sprintf()/snprintf() and don't check for
the return value which can lead the paths to overflow, truncating the
final file in the path.
More urgently, GCC 7 now warns that these aren't checked with
-Wformat-overflow, and with -Werror enabled in configure.ac, that makes
these tools unbuildable.
This patch fixes these problems by replacing sprintf() with snprintf() in
one place and adding checks for the return value of snprintf().
Reviewed-by: Peter Senna Tschudin <peter.senna(a)gmail.com>
Signed-off-by: Jonathan Dieter <jdieter(a)lesbg.com>
Acked-by: Shuah Khan <shuahkh(a)osg.samsung.com>
Signed-off-by: Shuah Khan <shuahkh(a)osg.samsung.com>
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
---
tools/usb/usbip/libsrc/usbip_common.c | 9 ++++++++-
tools/usb/usbip/libsrc/usbip_host_common.c | 28 +++++++++++++++++++++++-----
2 files changed, 31 insertions(+), 6 deletions(-)
--- a/tools/usb/usbip/libsrc/usbip_common.c
+++ b/tools/usb/usbip/libsrc/usbip_common.c
@@ -215,9 +215,16 @@ int read_usb_interface(struct usbip_usb_
struct usbip_usb_interface *uinf)
{
char busid[SYSFS_BUS_ID_SIZE];
+ int size;
struct udev_device *sif;
- sprintf(busid, "%s:%d.%d", udev->busid, udev->bConfigurationValue, i);
+ size = snprintf(busid, sizeof(busid), "%s:%d.%d",
+ udev->busid, udev->bConfigurationValue, i);
+ if (size < 0 || (unsigned int)size >= sizeof(busid)) {
+ err("busid length %i >= %lu or < 0", size,
+ (long unsigned)sizeof(busid));
+ return -1;
+ }
sif = udev_device_new_from_subsystem_sysname(udev_context, "usb", busid);
if (!sif) {
--- a/tools/usb/usbip/libsrc/usbip_host_common.c
+++ b/tools/usb/usbip/libsrc/usbip_host_common.c
@@ -40,13 +40,20 @@ struct udev *udev_context;
static int32_t read_attr_usbip_status(struct usbip_usb_device *udev)
{
char status_attr_path[SYSFS_PATH_MAX];
+ int size;
int fd;
int length;
char status;
int value = 0;
- snprintf(status_attr_path, SYSFS_PATH_MAX, "%s/usbip_status",
- udev->path);
+ size = snprintf(status_attr_path, sizeof(status_attr_path),
+ "%s/usbip_status", udev->path);
+ if (size < 0 || (unsigned int)size >= sizeof(status_attr_path)) {
+ err("usbip_status path length %i >= %lu or < 0", size,
+ (long unsigned)sizeof(status_attr_path));
+ return -1;
+ }
+
fd = open(status_attr_path, O_RDONLY);
if (fd < 0) {
@@ -218,6 +225,7 @@ int usbip_export_device(struct usbip_exp
{
char attr_name[] = "usbip_sockfd";
char sockfd_attr_path[SYSFS_PATH_MAX];
+ int size;
char sockfd_buff[30];
int ret;
@@ -237,10 +245,20 @@ int usbip_export_device(struct usbip_exp
}
/* only the first interface is true */
- snprintf(sockfd_attr_path, sizeof(sockfd_attr_path), "%s/%s",
- edev->udev.path, attr_name);
+ size = snprintf(sockfd_attr_path, sizeof(sockfd_attr_path), "%s/%s",
+ edev->udev.path, attr_name);
+ if (size < 0 || (unsigned int)size >= sizeof(sockfd_attr_path)) {
+ err("exported device path length %i >= %lu or < 0", size,
+ (long unsigned)sizeof(sockfd_attr_path));
+ return -1;
+ }
- snprintf(sockfd_buff, sizeof(sockfd_buff), "%d\n", sockfd);
+ size = snprintf(sockfd_buff, sizeof(sockfd_buff), "%d\n", sockfd);
+ if (size < 0 || (unsigned int)size >= sizeof(sockfd_buff)) {
+ err("socket length %i >= %lu or < 0", size,
+ (long unsigned)sizeof(sockfd_buff));
+ return -1;
+ }
ret = write_sysfs_attribute(sockfd_attr_path, sockfd_buff,
strlen(sockfd_buff));
Patches currently in stable-queue which might be from jdieter(a)lesbg.com are
queue-4.9/usbip-fix-potential-format-overflow-in-userspace-tools.patch
queue-4.9/usbip-fix-implicit-fallthrough-warning.patch
This is a note to let you know that I've just added the patch titled
orangefs: use list_for_each_entry_safe in purge_waiting_ops
to the 4.9-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=sum…
The filename of the patch is:
orangefs-use-list_for_each_entry_safe-in-purge_waiting_ops.patch
and it can be found in the queue-4.9 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable(a)vger.kernel.org> know about it.
>From 0afc0decf247f65b7aba666a76a0a68adf4bc435 Mon Sep 17 00:00:00 2001
From: Martin Brandenburg <martin(a)omnibond.com>
Date: Mon, 22 Jan 2018 15:44:51 -0500
Subject: orangefs: use list_for_each_entry_safe in purge_waiting_ops
From: Martin Brandenburg <martin(a)omnibond.com>
commit 0afc0decf247f65b7aba666a76a0a68adf4bc435 upstream.
set_op_state_purged can delete the op.
Signed-off-by: Martin Brandenburg <martin(a)omnibond.com>
Signed-off-by: Linus Torvalds <torvalds(a)linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
---
fs/orangefs/waitqueue.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
--- a/fs/orangefs/waitqueue.c
+++ b/fs/orangefs/waitqueue.c
@@ -28,10 +28,10 @@ static void orangefs_clean_up_interrupte
*/
void purge_waiting_ops(void)
{
- struct orangefs_kernel_op_s *op;
+ struct orangefs_kernel_op_s *op, *tmp;
spin_lock(&orangefs_request_list_lock);
- list_for_each_entry(op, &orangefs_request_list, list) {
+ list_for_each_entry_safe(op, tmp, &orangefs_request_list, list) {
gossip_debug(GOSSIP_WAIT_DEBUG,
"pvfs2-client-core: purging op tag %llu %s\n",
llu(op->tag),
Patches currently in stable-queue which might be from martin(a)omnibond.com are
queue-4.9/orangefs-initialize-op-on-loop-restart-in-orangefs_devreq_read.patch
queue-4.9/orangefs-use-list_for_each_entry_safe-in-purge_waiting_ops.patch
This is a note to let you know that I've just added the patch titled
usbip: Fix implicit fallthrough warning
to the 4.9-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=sum…
The filename of the patch is:
usbip-fix-implicit-fallthrough-warning.patch
and it can be found in the queue-4.9 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable(a)vger.kernel.org> know about it.
>From cfd6ed4537a9e938fa76facecd4b9cd65b6d1563 Mon Sep 17 00:00:00 2001
From: Jonathan Dieter <jdieter(a)lesbg.com>
Date: Mon, 27 Feb 2017 10:31:04 +0200
Subject: usbip: Fix implicit fallthrough warning
From: Jonathan Dieter <jdieter(a)lesbg.com>
commit cfd6ed4537a9e938fa76facecd4b9cd65b6d1563 upstream.
GCC 7 now warns when switch statements fall through implicitly, and with
-Werror enabled in configure.ac, that makes these tools unbuildable.
We fix this by notifying the compiler that this particular case statement
is meant to fall through.
Reviewed-by: Peter Senna Tschudin <peter.senna(a)gmail.com>
Signed-off-by: Jonathan Dieter <jdieter(a)lesbg.com>
Signed-off-by: Shuah Khan <shuahkh(a)osg.samsung.com>
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
---
tools/usb/usbip/src/usbip.c | 2 ++
1 file changed, 2 insertions(+)
--- a/tools/usb/usbip/src/usbip.c
+++ b/tools/usb/usbip/src/usbip.c
@@ -176,6 +176,8 @@ int main(int argc, char *argv[])
break;
case '?':
printf("usbip: invalid option\n");
+ /* Terminate after printing error */
+ /* FALLTHRU */
default:
usbip_usage();
goto out;
Patches currently in stable-queue which might be from jdieter(a)lesbg.com are
queue-4.9/usbip-fix-potential-format-overflow-in-userspace-tools.patch
queue-4.9/usbip-fix-implicit-fallthrough-warning.patch
This is a note to let you know that I've just added the patch titled
orangefs: initialize op on loop restart in orangefs_devreq_read
to the 4.9-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=sum…
The filename of the patch is:
orangefs-initialize-op-on-loop-restart-in-orangefs_devreq_read.patch
and it can be found in the queue-4.9 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable(a)vger.kernel.org> know about it.
>From a0ec1ded22e6a6bc41981fae22406835b006a66e Mon Sep 17 00:00:00 2001
From: Martin Brandenburg <martin(a)omnibond.com>
Date: Mon, 22 Jan 2018 15:44:52 -0500
Subject: orangefs: initialize op on loop restart in orangefs_devreq_read
From: Martin Brandenburg <martin(a)omnibond.com>
commit a0ec1ded22e6a6bc41981fae22406835b006a66e upstream.
In orangefs_devreq_read, there is a loop which picks an op off the list
of pending ops. If the loop fails to find an op, there is nothing to
read, and it returns EAGAIN. If the op has been given up on, the loop
is restarted via a goto. The bug is that the variable which the found
op is written to is not reinitialized, so if there are no more eligible
ops on the list, the code runs again on the already handled op.
This is triggered by interrupting a process while the op is being copied
to the client-core. It's a fairly small window, but it's there.
Signed-off-by: Martin Brandenburg <martin(a)omnibond.com>
Signed-off-by: Linus Torvalds <torvalds(a)linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
---
fs/orangefs/devorangefs-req.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
--- a/fs/orangefs/devorangefs-req.c
+++ b/fs/orangefs/devorangefs-req.c
@@ -161,7 +161,7 @@ static ssize_t orangefs_devreq_read(stru
struct orangefs_kernel_op_s *op, *temp;
__s32 proto_ver = ORANGEFS_KERNEL_PROTO_VERSION;
static __s32 magic = ORANGEFS_DEVREQ_MAGIC;
- struct orangefs_kernel_op_s *cur_op = NULL;
+ struct orangefs_kernel_op_s *cur_op;
unsigned long ret;
/* We do not support blocking IO. */
@@ -181,6 +181,7 @@ static ssize_t orangefs_devreq_read(stru
}
restart:
+ cur_op = NULL;
/* Get next op (if any) from top of list. */
spin_lock(&orangefs_request_list_lock);
list_for_each_entry_safe(op, temp, &orangefs_request_list, list) {
Patches currently in stable-queue which might be from martin(a)omnibond.com are
queue-4.9/orangefs-initialize-op-on-loop-restart-in-orangefs_devreq_read.patch
queue-4.9/orangefs-use-list_for_each_entry_safe-in-purge_waiting_ops.patch
This is a note to let you know that I've just added the patch titled
usbip: prevent vhci_hcd driver from leaking a socket pointer address
to the 4.4-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=sum…
The filename of the patch is:
usbip-prevent-vhci_hcd-driver-from-leaking-a-socket-pointer-address.patch
and it can be found in the queue-4.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable(a)vger.kernel.org> know about it.
>From 2f2d0088eb93db5c649d2a5e34a3800a8a935fc5 Mon Sep 17 00:00:00 2001
From: Shuah Khan <shuahkh(a)osg.samsung.com>
Date: Thu, 7 Dec 2017 14:16:49 -0700
Subject: usbip: prevent vhci_hcd driver from leaking a socket pointer address
From: Shuah Khan <shuahkh(a)osg.samsung.com>
commit 2f2d0088eb93db5c649d2a5e34a3800a8a935fc5 upstream.
When a client has a USB device attached over IP, the vhci_hcd driver is
locally leaking a socket pointer address via the
/sys/devices/platform/vhci_hcd/status file (world-readable) and in debug
output when "usbip --debug port" is run.
Fix it to not leak. The socket pointer address is not used at the moment
and it was made visible as a convenient way to find IP address from socket
pointer address by looking up /proc/net/{tcp,tcp6}.
As this opens a security hole, the fix replaces socket pointer address with
sockfd.
Reported-by: Secunia Research <vuln(a)secunia.com>
Signed-off-by: Shuah Khan <shuahkh(a)osg.samsung.com>
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
---
drivers/usb/usbip/usbip_common.h | 1 +
drivers/usb/usbip/vhci_sysfs.c | 25 +++++++++++++++----------
tools/usb/usbip/libsrc/vhci_driver.c | 8 ++++----
3 files changed, 20 insertions(+), 14 deletions(-)
--- a/drivers/usb/usbip/usbip_common.h
+++ b/drivers/usb/usbip/usbip_common.h
@@ -261,6 +261,7 @@ struct usbip_device {
/* lock for status */
spinlock_t lock;
+ int sockfd;
struct socket *tcp_socket;
struct task_struct *tcp_rx;
--- a/drivers/usb/usbip/vhci_sysfs.c
+++ b/drivers/usb/usbip/vhci_sysfs.c
@@ -39,16 +39,20 @@ static ssize_t status_show(struct device
/*
* output example:
- * prt sta spd dev socket local_busid
- * 000 004 000 000 c5a7bb80 1-2.3
- * 001 004 000 000 d8cee980 2-3.4
+ * port sta spd dev sockfd local_busid
+ * 0000 004 000 00000000 000003 1-2.3
+ * 0001 004 000 00000000 000004 2-3.4
*
- * IP address can be retrieved from a socket pointer address by looking
- * up /proc/net/{tcp,tcp6}. Also, a userland program may remember a
- * port number and its peer IP address.
+ * Output includes socket fd instead of socket pointer address to
+ * avoid leaking kernel memory address in:
+ * /sys/devices/platform/vhci_hcd.0/status and in debug output.
+ * The socket pointer address is not used at the moment and it was
+ * made visible as a convenient way to find IP address from socket
+ * pointer address by looking up /proc/net/{tcp,tcp6}. As this opens
+ * a security hole, the change is made to use sockfd instead.
*/
out += sprintf(out,
- "prt sta spd bus dev socket local_busid\n");
+ "prt sta spd bus dev sockfd local_busid\n");
for (i = 0; i < VHCI_NPORTS; i++) {
struct vhci_device *vdev = port_to_vdev(i);
@@ -60,11 +64,11 @@ static ssize_t status_show(struct device
out += sprintf(out, "%03u %08x ",
vdev->speed, vdev->devid);
out += sprintf(out, "%16p ", vdev->ud.tcp_socket);
+ out += sprintf(out, "%06u", vdev->ud.sockfd);
out += sprintf(out, "%s", dev_name(&vdev->udev->dev));
- } else {
- out += sprintf(out, "000 000 000 0000000000000000 0-0");
- }
+ } else
+ out += sprintf(out, "000 000 000 000000 0-0");
out += sprintf(out, "\n");
spin_unlock(&vdev->ud.lock);
@@ -223,6 +227,7 @@ static ssize_t store_attach(struct devic
vdev->devid = devid;
vdev->speed = speed;
+ vdev->ud.sockfd = sockfd;
vdev->ud.tcp_socket = socket;
vdev->ud.status = VDEV_ST_NOTASSIGNED;
--- a/tools/usb/usbip/libsrc/vhci_driver.c
+++ b/tools/usb/usbip/libsrc/vhci_driver.c
@@ -55,12 +55,12 @@ static int parse_status(const char *valu
while (*c != '\0') {
int port, status, speed, devid;
- unsigned long socket;
+ int sockfd;
char lbusid[SYSFS_BUS_ID_SIZE];
- ret = sscanf(c, "%d %d %d %x %lx %31s\n",
+ ret = sscanf(c, "%d %d %d %x %u %31s\n",
&port, &status, &speed,
- &devid, &socket, lbusid);
+ &devid, &sockfd, lbusid);
if (ret < 5) {
dbg("sscanf failed: %d", ret);
@@ -69,7 +69,7 @@ static int parse_status(const char *valu
dbg("port %d status %d speed %d devid %x",
port, status, speed, devid);
- dbg("socket %lx lbusid %s", socket, lbusid);
+ dbg("sockfd %u lbusid %s", sockfd, lbusid);
/* if a device is connected, look at it */
Patches currently in stable-queue which might be from shuahkh(a)osg.samsung.com are
queue-4.4/usbip-fix-potential-format-overflow-in-userspace-tools.patch
queue-4.4/usbip-fix-implicit-fallthrough-warning.patch
queue-4.4/usbip-prevent-vhci_hcd-driver-from-leaking-a-socket-pointer-address.patch