The patch below does not apply to the 4.9-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 be20bbcb0a8cb5597cc62b3e28d275919f3431df Mon Sep 17 00:00:00 2001
From: Kazufumi Ikeda <kaz-ikeda(a)xc.jp.nec.com>
Date: Mon, 25 Mar 2019 20:43:19 +0100
Subject: [PATCH] PCI: rcar: Add the initialization of PCIe link in
resume_noirq()
Reestablish the PCIe link very early in the resume process in case it
went down to prevent PCI accesses from hanging the bus. Such accesses
can happen early in the PCI resume process, as early as the
SUSPEND_RESUME_NOIRQ step, thus the link must be reestablished in the
driver resume_noirq() callback.
Fixes: e015f88c368d ("PCI: rcar: Add support for R-Car H3 to pcie-rcar")
Signed-off-by: Kazufumi Ikeda <kaz-ikeda(a)xc.jp.nec.com>
Signed-off-by: Gaku Inami <gaku.inami.xw(a)bp.renesas.com>
Signed-off-by: Marek Vasut <marek.vasut+renesas(a)gmail.com>
[lorenzo.pieralisi(a)arm.com: reformatted commit log]
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi(a)arm.com>
Reviewed-by: Simon Horman <horms+renesas(a)verge.net.au>
Reviewed-by: Geert Uytterhoeven <geert+renesas(a)glider.be>
Acked-by: Wolfram Sang <wsa+renesas(a)sang-engineering.com>
Cc: stable(a)vger.kernel.org
Cc: Geert Uytterhoeven <geert+renesas(a)glider.be>
Cc: Phil Edworthy <phil.edworthy(a)renesas.com>
Cc: Simon Horman <horms+renesas(a)verge.net.au>
Cc: Wolfram Sang <wsa(a)the-dreams.de>
Cc: linux-renesas-soc(a)vger.kernel.org
diff --git a/drivers/pci/controller/pcie-rcar.c b/drivers/pci/controller/pcie-rcar.c
index c8febb009454..6a4e435bd35f 100644
--- a/drivers/pci/controller/pcie-rcar.c
+++ b/drivers/pci/controller/pcie-rcar.c
@@ -46,6 +46,7 @@
/* Transfer control */
#define PCIETCTLR 0x02000
+#define DL_DOWN BIT(3)
#define CFINIT 1
#define PCIETSTR 0x02004
#define DATA_LINK_ACTIVE 1
@@ -94,6 +95,7 @@
#define MACCTLR 0x011058
#define SPEED_CHANGE BIT(24)
#define SCRAMBLE_DISABLE BIT(27)
+#define PMSR 0x01105c
#define MACS2R 0x011078
#define MACCGSPSETR 0x011084
#define SPCNGRSN BIT(31)
@@ -1130,6 +1132,7 @@ static int rcar_pcie_probe(struct platform_device *pdev)
pcie = pci_host_bridge_priv(bridge);
pcie->dev = dev;
+ platform_set_drvdata(pdev, pcie);
err = pci_parse_request_of_pci_ranges(dev, &pcie->resources, NULL);
if (err)
@@ -1221,10 +1224,28 @@ static int rcar_pcie_probe(struct platform_device *pdev)
return err;
}
+static int rcar_pcie_resume_noirq(struct device *dev)
+{
+ struct rcar_pcie *pcie = dev_get_drvdata(dev);
+
+ if (rcar_pci_read_reg(pcie, PMSR) &&
+ !(rcar_pci_read_reg(pcie, PCIETCTLR) & DL_DOWN))
+ return 0;
+
+ /* Re-establish the PCIe link */
+ rcar_pci_write_reg(pcie, CFINIT, PCIETCTLR);
+ return rcar_pcie_wait_for_dl(pcie);
+}
+
+static const struct dev_pm_ops rcar_pcie_pm_ops = {
+ .resume_noirq = rcar_pcie_resume_noirq,
+};
+
static struct platform_driver rcar_pcie_driver = {
.driver = {
.name = "rcar-pcie",
.of_match_table = rcar_pcie_of_match,
+ .pm = &rcar_pcie_pm_ops,
.suppress_bind_attrs = true,
},
.probe = rcar_pcie_probe,
The patch below does not apply to the 4.14-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 be20bbcb0a8cb5597cc62b3e28d275919f3431df Mon Sep 17 00:00:00 2001
From: Kazufumi Ikeda <kaz-ikeda(a)xc.jp.nec.com>
Date: Mon, 25 Mar 2019 20:43:19 +0100
Subject: [PATCH] PCI: rcar: Add the initialization of PCIe link in
resume_noirq()
Reestablish the PCIe link very early in the resume process in case it
went down to prevent PCI accesses from hanging the bus. Such accesses
can happen early in the PCI resume process, as early as the
SUSPEND_RESUME_NOIRQ step, thus the link must be reestablished in the
driver resume_noirq() callback.
Fixes: e015f88c368d ("PCI: rcar: Add support for R-Car H3 to pcie-rcar")
Signed-off-by: Kazufumi Ikeda <kaz-ikeda(a)xc.jp.nec.com>
Signed-off-by: Gaku Inami <gaku.inami.xw(a)bp.renesas.com>
Signed-off-by: Marek Vasut <marek.vasut+renesas(a)gmail.com>
[lorenzo.pieralisi(a)arm.com: reformatted commit log]
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi(a)arm.com>
Reviewed-by: Simon Horman <horms+renesas(a)verge.net.au>
Reviewed-by: Geert Uytterhoeven <geert+renesas(a)glider.be>
Acked-by: Wolfram Sang <wsa+renesas(a)sang-engineering.com>
Cc: stable(a)vger.kernel.org
Cc: Geert Uytterhoeven <geert+renesas(a)glider.be>
Cc: Phil Edworthy <phil.edworthy(a)renesas.com>
Cc: Simon Horman <horms+renesas(a)verge.net.au>
Cc: Wolfram Sang <wsa(a)the-dreams.de>
Cc: linux-renesas-soc(a)vger.kernel.org
diff --git a/drivers/pci/controller/pcie-rcar.c b/drivers/pci/controller/pcie-rcar.c
index c8febb009454..6a4e435bd35f 100644
--- a/drivers/pci/controller/pcie-rcar.c
+++ b/drivers/pci/controller/pcie-rcar.c
@@ -46,6 +46,7 @@
/* Transfer control */
#define PCIETCTLR 0x02000
+#define DL_DOWN BIT(3)
#define CFINIT 1
#define PCIETSTR 0x02004
#define DATA_LINK_ACTIVE 1
@@ -94,6 +95,7 @@
#define MACCTLR 0x011058
#define SPEED_CHANGE BIT(24)
#define SCRAMBLE_DISABLE BIT(27)
+#define PMSR 0x01105c
#define MACS2R 0x011078
#define MACCGSPSETR 0x011084
#define SPCNGRSN BIT(31)
@@ -1130,6 +1132,7 @@ static int rcar_pcie_probe(struct platform_device *pdev)
pcie = pci_host_bridge_priv(bridge);
pcie->dev = dev;
+ platform_set_drvdata(pdev, pcie);
err = pci_parse_request_of_pci_ranges(dev, &pcie->resources, NULL);
if (err)
@@ -1221,10 +1224,28 @@ static int rcar_pcie_probe(struct platform_device *pdev)
return err;
}
+static int rcar_pcie_resume_noirq(struct device *dev)
+{
+ struct rcar_pcie *pcie = dev_get_drvdata(dev);
+
+ if (rcar_pci_read_reg(pcie, PMSR) &&
+ !(rcar_pci_read_reg(pcie, PCIETCTLR) & DL_DOWN))
+ return 0;
+
+ /* Re-establish the PCIe link */
+ rcar_pci_write_reg(pcie, CFINIT, PCIETCTLR);
+ return rcar_pcie_wait_for_dl(pcie);
+}
+
+static const struct dev_pm_ops rcar_pcie_pm_ops = {
+ .resume_noirq = rcar_pcie_resume_noirq,
+};
+
static struct platform_driver rcar_pcie_driver = {
.driver = {
.name = "rcar-pcie",
.of_match_table = rcar_pcie_of_match,
+ .pm = &rcar_pcie_pm_ops,
.suppress_bind_attrs = true,
},
.probe = rcar_pcie_probe,
This is an automatic generated email to let you know that the following patch were queued:
Subject: media: videobuf2-dma-sg: Prevent size from overflowing
Author: Sakari Ailus <sakari.ailus(a)linux.intel.com>
Date: Wed Dec 12 07:44:14 2018 -0500
buf->size is an unsigned long; casting that to int will lead to an
overflow if buf->size exceeds INT_MAX.
Fix this by changing the type to unsigned long instead. This is possible
as the buf->size is always aligned to PAGE_SIZE, and therefore the size
will never have values lesser than 0.
Note on backporting to stable: the file used to be under
drivers/media/v4l2-core, it was moved to the current location after 4.14.
Signed-off-by: Sakari Ailus <sakari.ailus(a)linux.intel.com>
Cc: stable(a)vger.kernel.org
Reviewed-by: Hans Verkuil <hverkuil-cisco(a)xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung(a)kernel.org>
drivers/media/common/videobuf2/videobuf2-dma-sg.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
---
diff --git a/drivers/media/common/videobuf2/videobuf2-dma-sg.c b/drivers/media/common/videobuf2/videobuf2-dma-sg.c
index 4a4c49d6085c..0f06f08346ba 100644
--- a/drivers/media/common/videobuf2/videobuf2-dma-sg.c
+++ b/drivers/media/common/videobuf2/videobuf2-dma-sg.c
@@ -59,7 +59,7 @@ static int vb2_dma_sg_alloc_compacted(struct vb2_dma_sg_buf *buf,
gfp_t gfp_flags)
{
unsigned int last_page = 0;
- int size = buf->size;
+ unsigned long size = buf->size;
while (size > 0) {
struct page *pages;
This is an automatic generated email to let you know that the following patch were queued:
Subject: media: videobuf2-core: Prevent size alignment wrapping buffer size to 0
Author: Sakari Ailus <sakari.ailus(a)linux.intel.com>
Date: Wed Dec 12 07:27:10 2018 -0500
PAGE_ALIGN() may wrap the buffer size around to 0. Prevent this by
checking that the aligned value is not smaller than the unaligned one.
Note on backporting to stable: the file used to be under
drivers/media/v4l2-core, it was moved to the current location after 4.14.
Signed-off-by: Sakari Ailus <sakari.ailus(a)linux.intel.com>
Cc: stable(a)vger.kernel.org
Reviewed-by: Hans Verkuil <hverkuil-cisco(a)xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung(a)kernel.org>
drivers/media/common/videobuf2/videobuf2-core.c | 4 ++++
1 file changed, 4 insertions(+)
---
diff --git a/drivers/media/common/videobuf2/videobuf2-core.c b/drivers/media/common/videobuf2/videobuf2-core.c
index 3cf25abf5807..cfccee87909a 100644
--- a/drivers/media/common/videobuf2/videobuf2-core.c
+++ b/drivers/media/common/videobuf2/videobuf2-core.c
@@ -207,6 +207,10 @@ static int __vb2_buf_mem_alloc(struct vb2_buffer *vb)
for (plane = 0; plane < vb->num_planes; ++plane) {
unsigned long size = PAGE_ALIGN(vb->planes[plane].length);
+ /* Did it wrap around? */
+ if (size < vb->planes[plane].length)
+ goto free;
+
mem_priv = call_ptr_memop(vb, alloc,
q->alloc_devs[plane] ? : q->dev,
q->dma_attrs, size, q->dma_dir, q->gfp_flags);
The patch below does not apply to the 4.9-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 51e0f227812ed81a368de54157ebe14396b4be03 Mon Sep 17 00:00:00 2001
From: Alexander Shishkin <alexander.shishkin(a)linux.intel.com>
Date: Wed, 17 Apr 2019 10:35:35 +0300
Subject: [PATCH] stm class: Fix channel bitmap on 32-bit systems
Commit 7bd1d4093c2f ("stm class: Introduce an abstraction for System Trace
Module devices") naively calculates the channel bitmap size in 64-bit
chunks regardless of the size of underlying unsigned long, making the
bitmap half as big on a 32-bit system. This leads to an out of bounds
access with the upper half of the bitmap.
Fix this by using BITS_TO_LONGS. While at it, convert to using
struct_size() for the total size calculation of the master struct.
Signed-off-by: Alexander Shishkin <alexander.shishkin(a)linux.intel.com>
Fixes: 7bd1d4093c2f ("stm class: Introduce an abstraction for System Trace Module devices")
Reported-by: Mulu He <muluhe(a)codeaurora.org>
Cc: stable(a)vger.kernel.org # v4.4+
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
diff --git a/drivers/hwtracing/stm/core.c b/drivers/hwtracing/stm/core.c
index 5b5807cbcf7c..e55b902560de 100644
--- a/drivers/hwtracing/stm/core.c
+++ b/drivers/hwtracing/stm/core.c
@@ -166,11 +166,10 @@ stm_master(struct stm_device *stm, unsigned int idx)
static int stp_master_alloc(struct stm_device *stm, unsigned int idx)
{
struct stp_master *master;
- size_t size;
- size = ALIGN(stm->data->sw_nchannels, 8) / 8;
- size += sizeof(struct stp_master);
- master = kzalloc(size, GFP_ATOMIC);
+ master = kzalloc(struct_size(master, chan_map,
+ BITS_TO_LONGS(stm->data->sw_nchannels)),
+ GFP_ATOMIC);
if (!master)
return -ENOMEM;
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 51e0f227812ed81a368de54157ebe14396b4be03 Mon Sep 17 00:00:00 2001
From: Alexander Shishkin <alexander.shishkin(a)linux.intel.com>
Date: Wed, 17 Apr 2019 10:35:35 +0300
Subject: [PATCH] stm class: Fix channel bitmap on 32-bit systems
Commit 7bd1d4093c2f ("stm class: Introduce an abstraction for System Trace
Module devices") naively calculates the channel bitmap size in 64-bit
chunks regardless of the size of underlying unsigned long, making the
bitmap half as big on a 32-bit system. This leads to an out of bounds
access with the upper half of the bitmap.
Fix this by using BITS_TO_LONGS. While at it, convert to using
struct_size() for the total size calculation of the master struct.
Signed-off-by: Alexander Shishkin <alexander.shishkin(a)linux.intel.com>
Fixes: 7bd1d4093c2f ("stm class: Introduce an abstraction for System Trace Module devices")
Reported-by: Mulu He <muluhe(a)codeaurora.org>
Cc: stable(a)vger.kernel.org # v4.4+
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
diff --git a/drivers/hwtracing/stm/core.c b/drivers/hwtracing/stm/core.c
index 5b5807cbcf7c..e55b902560de 100644
--- a/drivers/hwtracing/stm/core.c
+++ b/drivers/hwtracing/stm/core.c
@@ -166,11 +166,10 @@ stm_master(struct stm_device *stm, unsigned int idx)
static int stp_master_alloc(struct stm_device *stm, unsigned int idx)
{
struct stp_master *master;
- size_t size;
- size = ALIGN(stm->data->sw_nchannels, 8) / 8;
- size += sizeof(struct stp_master);
- master = kzalloc(size, GFP_ATOMIC);
+ master = kzalloc(struct_size(master, chan_map,
+ BITS_TO_LONGS(stm->data->sw_nchannels)),
+ GFP_ATOMIC);
if (!master)
return -ENOMEM;
The patch below does not apply to the 4.14-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 51e0f227812ed81a368de54157ebe14396b4be03 Mon Sep 17 00:00:00 2001
From: Alexander Shishkin <alexander.shishkin(a)linux.intel.com>
Date: Wed, 17 Apr 2019 10:35:35 +0300
Subject: [PATCH] stm class: Fix channel bitmap on 32-bit systems
Commit 7bd1d4093c2f ("stm class: Introduce an abstraction for System Trace
Module devices") naively calculates the channel bitmap size in 64-bit
chunks regardless of the size of underlying unsigned long, making the
bitmap half as big on a 32-bit system. This leads to an out of bounds
access with the upper half of the bitmap.
Fix this by using BITS_TO_LONGS. While at it, convert to using
struct_size() for the total size calculation of the master struct.
Signed-off-by: Alexander Shishkin <alexander.shishkin(a)linux.intel.com>
Fixes: 7bd1d4093c2f ("stm class: Introduce an abstraction for System Trace Module devices")
Reported-by: Mulu He <muluhe(a)codeaurora.org>
Cc: stable(a)vger.kernel.org # v4.4+
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
diff --git a/drivers/hwtracing/stm/core.c b/drivers/hwtracing/stm/core.c
index 5b5807cbcf7c..e55b902560de 100644
--- a/drivers/hwtracing/stm/core.c
+++ b/drivers/hwtracing/stm/core.c
@@ -166,11 +166,10 @@ stm_master(struct stm_device *stm, unsigned int idx)
static int stp_master_alloc(struct stm_device *stm, unsigned int idx)
{
struct stp_master *master;
- size_t size;
- size = ALIGN(stm->data->sw_nchannels, 8) / 8;
- size += sizeof(struct stp_master);
- master = kzalloc(size, GFP_ATOMIC);
+ master = kzalloc(struct_size(master, chan_map,
+ BITS_TO_LONGS(stm->data->sw_nchannels)),
+ GFP_ATOMIC);
if (!master)
return -ENOMEM;
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 9e298e8604088a600d8100a111a532a9d342af09 Mon Sep 17 00:00:00 2001
From: Peter Zijlstra <peterz(a)infradead.org>
Date: Wed, 1 May 2019 15:11:17 +0200
Subject: [PATCH] ftrace/x86_64: Emulate call function while updating in
breakpoint handler
Nicolai Stange discovered[1] that if live kernel patching is enabled, and the
function tracer started tracing the same function that was patched, the
conversion of the fentry call site during the translation of going from
calling the live kernel patch trampoline to the iterator trampoline, would
have as slight window where it didn't call anything.
As live kernel patching depends on ftrace to always call its code (to
prevent the function being traced from being called, as it will redirect
it). This small window would allow the old buggy function to be called, and
this can cause undesirable results.
Nicolai submitted new patches[2] but these were controversial. As this is
similar to the static call emulation issues that came up a while ago[3].
But after some debate[4][5] adding a gap in the stack when entering the
breakpoint handler allows for pushing the return address onto the stack to
easily emulate a call.
[1] http://lkml.kernel.org/r/20180726104029.7736-1-nstange@suse.de
[2] http://lkml.kernel.org/r/20190427100639.15074-1-nstange@suse.de
[3] http://lkml.kernel.org/r/3cf04e113d71c9f8e4be95fb84a510f085aa4afa.154171145…
[4] http://lkml.kernel.org/r/CAHk-=wh5OpheSU8Em_Q3Hg8qw_JtoijxOdPtHru6d+5K8TWM=…
[5] http://lkml.kernel.org/r/CAHk-=wjvQxY4DvPrJ6haPgAa6b906h=MwZXO6G8OtiTGe=N7_…
[
Live kernel patching is not implemented on x86_32, thus the emulate
calls are only for x86_64.
]
Cc: Andy Lutomirski <luto(a)kernel.org>
Cc: Nicolai Stange <nstange(a)suse.de>
Cc: Thomas Gleixner <tglx(a)linutronix.de>
Cc: Ingo Molnar <mingo(a)redhat.com>
Cc: Borislav Petkov <bp(a)alien8.de>
Cc: "H. Peter Anvin" <hpa(a)zytor.com>
Cc: the arch/x86 maintainers <x86(a)kernel.org>
Cc: Josh Poimboeuf <jpoimboe(a)redhat.com>
Cc: Jiri Kosina <jikos(a)kernel.org>
Cc: Miroslav Benes <mbenes(a)suse.cz>
Cc: Petr Mladek <pmladek(a)suse.com>
Cc: Joe Lawrence <joe.lawrence(a)redhat.com>
Cc: Shuah Khan <shuah(a)kernel.org>
Cc: Konrad Rzeszutek Wilk <konrad.wilk(a)oracle.com>
Cc: Tim Chen <tim.c.chen(a)linux.intel.com>
Cc: Sebastian Andrzej Siewior <bigeasy(a)linutronix.de>
Cc: Mimi Zohar <zohar(a)linux.ibm.com>
Cc: Juergen Gross <jgross(a)suse.com>
Cc: Nick Desaulniers <ndesaulniers(a)google.com>
Cc: Nayna Jain <nayna(a)linux.ibm.com>
Cc: Masahiro Yamada <yamada.masahiro(a)socionext.com>
Cc: Joerg Roedel <jroedel(a)suse.de>
Cc: "open list:KERNEL SELFTEST FRAMEWORK" <linux-kselftest(a)vger.kernel.org>
Cc: stable(a)vger.kernel.org
Fixes: b700e7f03df5 ("livepatch: kernel: add support for live patching")
Tested-by: Nicolai Stange <nstange(a)suse.de>
Reviewed-by: Nicolai Stange <nstange(a)suse.de>
Reviewed-by: Masami Hiramatsu <mhiramat(a)kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz(a)infradead.org>
[ Changed to only implement emulated calls for x86_64 ]
Signed-off-by: Steven Rostedt (VMware) <rostedt(a)goodmis.org>
diff --git a/arch/x86/kernel/ftrace.c b/arch/x86/kernel/ftrace.c
index ef49517f6bb2..bd553b3af22e 100644
--- a/arch/x86/kernel/ftrace.c
+++ b/arch/x86/kernel/ftrace.c
@@ -29,6 +29,7 @@
#include <asm/kprobes.h>
#include <asm/ftrace.h>
#include <asm/nops.h>
+#include <asm/text-patching.h>
#ifdef CONFIG_DYNAMIC_FTRACE
@@ -231,6 +232,7 @@ int ftrace_modify_call(struct dyn_ftrace *rec, unsigned long old_addr,
}
static unsigned long ftrace_update_func;
+static unsigned long ftrace_update_func_call;
static int update_ftrace_func(unsigned long ip, void *new)
{
@@ -259,6 +261,8 @@ int ftrace_update_ftrace_func(ftrace_func_t func)
unsigned char *new;
int ret;
+ ftrace_update_func_call = (unsigned long)func;
+
new = ftrace_call_replace(ip, (unsigned long)func);
ret = update_ftrace_func(ip, new);
@@ -294,13 +298,28 @@ int ftrace_int3_handler(struct pt_regs *regs)
if (WARN_ON_ONCE(!regs))
return 0;
- ip = regs->ip - 1;
- if (!ftrace_location(ip) && !is_ftrace_caller(ip))
- return 0;
+ ip = regs->ip - INT3_INSN_SIZE;
- regs->ip += MCOUNT_INSN_SIZE - 1;
+#ifdef CONFIG_X86_64
+ if (ftrace_location(ip)) {
+ int3_emulate_call(regs, (unsigned long)ftrace_regs_caller);
+ return 1;
+ } else if (is_ftrace_caller(ip)) {
+ if (!ftrace_update_func_call) {
+ int3_emulate_jmp(regs, ip + CALL_INSN_SIZE);
+ return 1;
+ }
+ int3_emulate_call(regs, ftrace_update_func_call);
+ return 1;
+ }
+#else
+ if (ftrace_location(ip) || is_ftrace_caller(ip)) {
+ int3_emulate_jmp(regs, ip + CALL_INSN_SIZE);
+ return 1;
+ }
+#endif
- return 1;
+ return 0;
}
NOKPROBE_SYMBOL(ftrace_int3_handler);
@@ -859,6 +878,8 @@ void arch_ftrace_update_trampoline(struct ftrace_ops *ops)
func = ftrace_ops_get_func(ops);
+ ftrace_update_func_call = (unsigned long)func;
+
/* Do a safe modify in case the trampoline is executing */
new = ftrace_call_replace(ip, (unsigned long)func);
ret = update_ftrace_func(ip, new);
@@ -960,6 +981,7 @@ static int ftrace_mod_jmp(unsigned long ip, void *func)
{
unsigned char *new;
+ ftrace_update_func_call = 0UL;
new = ftrace_jmp_replace(ip, (unsigned long)func);
return update_ftrace_func(ip, new);
The patch below does not apply to the 4.9-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 9e298e8604088a600d8100a111a532a9d342af09 Mon Sep 17 00:00:00 2001
From: Peter Zijlstra <peterz(a)infradead.org>
Date: Wed, 1 May 2019 15:11:17 +0200
Subject: [PATCH] ftrace/x86_64: Emulate call function while updating in
breakpoint handler
Nicolai Stange discovered[1] that if live kernel patching is enabled, and the
function tracer started tracing the same function that was patched, the
conversion of the fentry call site during the translation of going from
calling the live kernel patch trampoline to the iterator trampoline, would
have as slight window where it didn't call anything.
As live kernel patching depends on ftrace to always call its code (to
prevent the function being traced from being called, as it will redirect
it). This small window would allow the old buggy function to be called, and
this can cause undesirable results.
Nicolai submitted new patches[2] but these were controversial. As this is
similar to the static call emulation issues that came up a while ago[3].
But after some debate[4][5] adding a gap in the stack when entering the
breakpoint handler allows for pushing the return address onto the stack to
easily emulate a call.
[1] http://lkml.kernel.org/r/20180726104029.7736-1-nstange@suse.de
[2] http://lkml.kernel.org/r/20190427100639.15074-1-nstange@suse.de
[3] http://lkml.kernel.org/r/3cf04e113d71c9f8e4be95fb84a510f085aa4afa.154171145…
[4] http://lkml.kernel.org/r/CAHk-=wh5OpheSU8Em_Q3Hg8qw_JtoijxOdPtHru6d+5K8TWM=…
[5] http://lkml.kernel.org/r/CAHk-=wjvQxY4DvPrJ6haPgAa6b906h=MwZXO6G8OtiTGe=N7_…
[
Live kernel patching is not implemented on x86_32, thus the emulate
calls are only for x86_64.
]
Cc: Andy Lutomirski <luto(a)kernel.org>
Cc: Nicolai Stange <nstange(a)suse.de>
Cc: Thomas Gleixner <tglx(a)linutronix.de>
Cc: Ingo Molnar <mingo(a)redhat.com>
Cc: Borislav Petkov <bp(a)alien8.de>
Cc: "H. Peter Anvin" <hpa(a)zytor.com>
Cc: the arch/x86 maintainers <x86(a)kernel.org>
Cc: Josh Poimboeuf <jpoimboe(a)redhat.com>
Cc: Jiri Kosina <jikos(a)kernel.org>
Cc: Miroslav Benes <mbenes(a)suse.cz>
Cc: Petr Mladek <pmladek(a)suse.com>
Cc: Joe Lawrence <joe.lawrence(a)redhat.com>
Cc: Shuah Khan <shuah(a)kernel.org>
Cc: Konrad Rzeszutek Wilk <konrad.wilk(a)oracle.com>
Cc: Tim Chen <tim.c.chen(a)linux.intel.com>
Cc: Sebastian Andrzej Siewior <bigeasy(a)linutronix.de>
Cc: Mimi Zohar <zohar(a)linux.ibm.com>
Cc: Juergen Gross <jgross(a)suse.com>
Cc: Nick Desaulniers <ndesaulniers(a)google.com>
Cc: Nayna Jain <nayna(a)linux.ibm.com>
Cc: Masahiro Yamada <yamada.masahiro(a)socionext.com>
Cc: Joerg Roedel <jroedel(a)suse.de>
Cc: "open list:KERNEL SELFTEST FRAMEWORK" <linux-kselftest(a)vger.kernel.org>
Cc: stable(a)vger.kernel.org
Fixes: b700e7f03df5 ("livepatch: kernel: add support for live patching")
Tested-by: Nicolai Stange <nstange(a)suse.de>
Reviewed-by: Nicolai Stange <nstange(a)suse.de>
Reviewed-by: Masami Hiramatsu <mhiramat(a)kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz(a)infradead.org>
[ Changed to only implement emulated calls for x86_64 ]
Signed-off-by: Steven Rostedt (VMware) <rostedt(a)goodmis.org>
diff --git a/arch/x86/kernel/ftrace.c b/arch/x86/kernel/ftrace.c
index ef49517f6bb2..bd553b3af22e 100644
--- a/arch/x86/kernel/ftrace.c
+++ b/arch/x86/kernel/ftrace.c
@@ -29,6 +29,7 @@
#include <asm/kprobes.h>
#include <asm/ftrace.h>
#include <asm/nops.h>
+#include <asm/text-patching.h>
#ifdef CONFIG_DYNAMIC_FTRACE
@@ -231,6 +232,7 @@ int ftrace_modify_call(struct dyn_ftrace *rec, unsigned long old_addr,
}
static unsigned long ftrace_update_func;
+static unsigned long ftrace_update_func_call;
static int update_ftrace_func(unsigned long ip, void *new)
{
@@ -259,6 +261,8 @@ int ftrace_update_ftrace_func(ftrace_func_t func)
unsigned char *new;
int ret;
+ ftrace_update_func_call = (unsigned long)func;
+
new = ftrace_call_replace(ip, (unsigned long)func);
ret = update_ftrace_func(ip, new);
@@ -294,13 +298,28 @@ int ftrace_int3_handler(struct pt_regs *regs)
if (WARN_ON_ONCE(!regs))
return 0;
- ip = regs->ip - 1;
- if (!ftrace_location(ip) && !is_ftrace_caller(ip))
- return 0;
+ ip = regs->ip - INT3_INSN_SIZE;
- regs->ip += MCOUNT_INSN_SIZE - 1;
+#ifdef CONFIG_X86_64
+ if (ftrace_location(ip)) {
+ int3_emulate_call(regs, (unsigned long)ftrace_regs_caller);
+ return 1;
+ } else if (is_ftrace_caller(ip)) {
+ if (!ftrace_update_func_call) {
+ int3_emulate_jmp(regs, ip + CALL_INSN_SIZE);
+ return 1;
+ }
+ int3_emulate_call(regs, ftrace_update_func_call);
+ return 1;
+ }
+#else
+ if (ftrace_location(ip) || is_ftrace_caller(ip)) {
+ int3_emulate_jmp(regs, ip + CALL_INSN_SIZE);
+ return 1;
+ }
+#endif
- return 1;
+ return 0;
}
NOKPROBE_SYMBOL(ftrace_int3_handler);
@@ -859,6 +878,8 @@ void arch_ftrace_update_trampoline(struct ftrace_ops *ops)
func = ftrace_ops_get_func(ops);
+ ftrace_update_func_call = (unsigned long)func;
+
/* Do a safe modify in case the trampoline is executing */
new = ftrace_call_replace(ip, (unsigned long)func);
ret = update_ftrace_func(ip, new);
@@ -960,6 +981,7 @@ static int ftrace_mod_jmp(unsigned long ip, void *func)
{
unsigned char *new;
+ ftrace_update_func_call = 0UL;
new = ftrace_jmp_replace(ip, (unsigned long)func);
return update_ftrace_func(ip, new);
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 4b33dadf37666c0860b88f9e52a16d07bf6d0b03 Mon Sep 17 00:00:00 2001
From: Peter Zijlstra <peterz(a)infradead.org>
Date: Wed, 1 May 2019 15:11:17 +0200
Subject: [PATCH] x86_64: Allow breakpoints to emulate call instructions
In order to allow breakpoints to emulate call instructions, they need to push
the return address onto the stack. The x86_64 int3 handler adds a small gap
to allow the stack to grow some. Use this gap to add the return address to
be able to emulate a call instruction at the breakpoint location.
These helper functions are added:
int3_emulate_jmp(): changes the location of the regs->ip to return there.
(The next two are only for x86_64)
int3_emulate_push(): to push the address onto the gap in the stack
int3_emulate_call(): push the return address and change regs->ip
Cc: Andy Lutomirski <luto(a)kernel.org>
Cc: Nicolai Stange <nstange(a)suse.de>
Cc: Thomas Gleixner <tglx(a)linutronix.de>
Cc: Ingo Molnar <mingo(a)redhat.com>
Cc: Borislav Petkov <bp(a)alien8.de>
Cc: "H. Peter Anvin" <hpa(a)zytor.com>
Cc: the arch/x86 maintainers <x86(a)kernel.org>
Cc: Josh Poimboeuf <jpoimboe(a)redhat.com>
Cc: Jiri Kosina <jikos(a)kernel.org>
Cc: Miroslav Benes <mbenes(a)suse.cz>
Cc: Petr Mladek <pmladek(a)suse.com>
Cc: Joe Lawrence <joe.lawrence(a)redhat.com>
Cc: Shuah Khan <shuah(a)kernel.org>
Cc: Konrad Rzeszutek Wilk <konrad.wilk(a)oracle.com>
Cc: Tim Chen <tim.c.chen(a)linux.intel.com>
Cc: Sebastian Andrzej Siewior <bigeasy(a)linutronix.de>
Cc: Mimi Zohar <zohar(a)linux.ibm.com>
Cc: Juergen Gross <jgross(a)suse.com>
Cc: Nick Desaulniers <ndesaulniers(a)google.com>
Cc: Nayna Jain <nayna(a)linux.ibm.com>
Cc: Masahiro Yamada <yamada.masahiro(a)socionext.com>
Cc: Joerg Roedel <jroedel(a)suse.de>
Cc: "open list:KERNEL SELFTEST FRAMEWORK" <linux-kselftest(a)vger.kernel.org>
Cc: stable(a)vger.kernel.org
Fixes: b700e7f03df5 ("livepatch: kernel: add support for live patching")
Tested-by: Nicolai Stange <nstange(a)suse.de>
Reviewed-by: Nicolai Stange <nstange(a)suse.de>
Reviewed-by: Masami Hiramatsu <mhiramat(a)kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz(a)infradead.org>
[ Modified to only work for x86_64 and added comment to int3_emulate_push() ]
Signed-off-by: Steven Rostedt (VMware) <rostedt(a)goodmis.org>
diff --git a/arch/x86/include/asm/text-patching.h b/arch/x86/include/asm/text-patching.h
index e85ff65c43c3..05861cc08787 100644
--- a/arch/x86/include/asm/text-patching.h
+++ b/arch/x86/include/asm/text-patching.h
@@ -39,4 +39,32 @@ extern int poke_int3_handler(struct pt_regs *regs);
extern void *text_poke_bp(void *addr, const void *opcode, size_t len, void *handler);
extern int after_bootmem;
+static inline void int3_emulate_jmp(struct pt_regs *regs, unsigned long ip)
+{
+ regs->ip = ip;
+}
+
+#define INT3_INSN_SIZE 1
+#define CALL_INSN_SIZE 5
+
+#ifdef CONFIG_X86_64
+static inline void int3_emulate_push(struct pt_regs *regs, unsigned long val)
+{
+ /*
+ * The int3 handler in entry_64.S adds a gap between the
+ * stack where the break point happened, and the saving of
+ * pt_regs. We can extend the original stack because of
+ * this gap. See the idtentry macro's create_gap option.
+ */
+ regs->sp -= sizeof(unsigned long);
+ *(unsigned long *)regs->sp = val;
+}
+
+static inline void int3_emulate_call(struct pt_regs *regs, unsigned long func)
+{
+ int3_emulate_push(regs, regs->ip - INT3_INSN_SIZE + CALL_INSN_SIZE);
+ int3_emulate_jmp(regs, func);
+}
+#endif
+
#endif /* _ASM_X86_TEXT_PATCHING_H */