The patch below does not apply to the 3.18-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 5c50538752af7968f53924b22dede8ed4ce4cb3b Mon Sep 17 00:00:00 2001
From: Heiko Carstens <heiko.carstens(a)de.ibm.com>
Date: Tue, 26 Sep 2017 09:16:48 +0200
Subject: [PATCH] s390/disassembler: add missing end marker for e7 table
The e7 opcode table does not have an end marker. Hence when trying to
find an unknown e7 instruction the code will access memory behind the
table until it finds something that matches the opcode, or the kernel
crashes, whatever comes first.
This affects not only the in-kernel disassembler but also uprobes and
kprobes which refuse to set a probe on unknown instructions, and
therefore search the opcode tables to figure out if instructions are
known or not.
Cc: <stable(a)vger.kernel.org> # v3.18+
Fixes: 3585cb0280654 ("s390/disassembler: add vector instructions")
Signed-off-by: Heiko Carstens <heiko.carstens(a)de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky(a)de.ibm.com>
diff --git a/arch/s390/kernel/dis.c b/arch/s390/kernel/dis.c
index f7e82302a71e..d9970c15f79d 100644
--- a/arch/s390/kernel/dis.c
+++ b/arch/s390/kernel/dis.c
@@ -1548,6 +1548,7 @@ static struct s390_insn opcode_e7[] = {
{ "vfsq", 0xce, INSTR_VRR_VV000MM },
{ "vfs", 0xe2, INSTR_VRR_VVV00MM },
{ "vftci", 0x4a, INSTR_VRI_VVIMM },
+ { "", 0, INSTR_INVALID }
};
static struct s390_insn opcode_eb[] = {
The patch below does not apply to the 3.18-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 d6e646ad7cfa7034d280459b2b2546288f247144 Mon Sep 17 00:00:00 2001
From: Heiko Carstens <heiko.carstens(a)de.ibm.com>
Date: Mon, 11 Sep 2017 11:24:22 +0200
Subject: [PATCH] s390/runtime instrumention: fix possible memory corruption
For PREEMPT enabled kernels the runtime instrumentation (RI) code
contains a possible use-after-free bug. If a task that makes use of RI
exits, it will execute do_exit() while still enabled for preemption.
That function will call exit_thread_runtime_instr() via
exit_thread(). If exit_thread_runtime_instr() gets preempted after the
RI control block of the task has been freed but before the pointer to
it is set to NULL, then save_ri_cb(), called from switch_to(), will
write to already freed memory.
Avoid this and simply disable preemption while freeing the control
block and setting the pointer to NULL.
Fixes: e4b8b3f33fca ("s390: add support for runtime instrumentation")
Cc: <stable(a)vger.kernel.org> # v3.7+
Reviewed-by: Christian Borntraeger <borntraeger(a)de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens(a)de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky(a)de.ibm.com>
diff --git a/arch/s390/kernel/runtime_instr.c b/arch/s390/kernel/runtime_instr.c
index 429d3a782f1c..b9738ae2e1de 100644
--- a/arch/s390/kernel/runtime_instr.c
+++ b/arch/s390/kernel/runtime_instr.c
@@ -49,11 +49,13 @@ void exit_thread_runtime_instr(void)
{
struct task_struct *task = current;
+ preempt_disable();
if (!task->thread.ri_cb)
return;
disable_runtime_instr();
kfree(task->thread.ri_cb);
task->thread.ri_cb = NULL;
+ preempt_enable();
}
SYSCALL_DEFINE1(s390_runtime_instr, int, command)
@@ -64,9 +66,7 @@ SYSCALL_DEFINE1(s390_runtime_instr, int, command)
return -EOPNOTSUPP;
if (command == S390_RUNTIME_INSTR_STOP) {
- preempt_disable();
exit_thread_runtime_instr();
- preempt_enable();
return 0;
}
The patch below does not apply to the 3.18-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 a1c5befc1c24eb9c1ee83f711e0f21ee79cbb556 Mon Sep 17 00:00:00 2001
From: Heiko Carstens <heiko.carstens(a)de.ibm.com>
Date: Thu, 9 Nov 2017 12:29:34 +0100
Subject: [PATCH] s390: fix transactional execution control register handling
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
Dan Horák reported the following crash related to transactional execution:
User process fault: interruption code 0013 ilc:3 in libpthread-2.26.so[3ff93c00000+1b000]
CPU: 2 PID: 1 Comm: /init Not tainted 4.13.4-300.fc27.s390x #1
Hardware name: IBM 2827 H43 400 (z/VM 6.4.0)
task: 00000000fafc8000 task.stack: 00000000fafc4000
User PSW : 0705200180000000 000003ff93c14e70
R:0 T:1 IO:1 EX:1 Key:0 M:1 W:0 P:1 AS:0 CC:2 PM:0 RI:0 EA:3
User GPRS: 0000000000000077 000003ff00000000 000003ff93144d48 000003ff93144d5e
0000000000000000 0000000000000002 0000000000000000 000003ff00000000
0000000000000000 0000000000000418 0000000000000000 000003ffcc9fe770
000003ff93d28f50 000003ff9310acf0 000003ff92b0319a 000003ffcc9fe6d0
User Code: 000003ff93c14e62: 60e0b030 std %f14,48(%r11)
000003ff93c14e66: 60f0b038 std %f15,56(%r11)
#000003ff93c14e6a: e5600000ff0e tbegin 0,65294
>000003ff93c14e70: a7740006 brc 7,3ff93c14e7c
000003ff93c14e74: a7080000 lhi %r0,0
000003ff93c14e78: a7f40023 brc 15,3ff93c14ebe
000003ff93c14e7c: b2220000 ipm %r0
000003ff93c14e80: 8800001c srl %r0,28
There are several bugs with control register handling with respect to
transactional execution:
- on task switch update_per_regs() is only called if the next task has
an mm (is not a kernel thread). This however is incorrect. This
breaks e.g. for user mode helper handling, where the kernel creates
a kernel thread and then execve's a user space program. Control
register contents related to transactional execution won't be
updated on execve. If the previous task ran with transactional
execution disabled then the new task will also run with
transactional execution disabled, which is incorrect. Therefore call
update_per_regs() unconditionally within switch_to().
- on startup the transactional execution facility is not enabled for
the idle thread. This is not really a bug, but an inconsistency to
other facilities. Therefore enable the facility if it is available.
- on fork the new thread's per_flags field is not cleared. This means
that a child process inherits the PER_FLAG_NO_TE flag. This flag can
be set with a ptrace request to disable transactional execution for
the current process. It should not be inherited by new child
processes in order to be consistent with the handling of all other
PER related debugging options. Therefore clear the per_flags field in
copy_thread_tls().
Reported-and-tested-by: Dan Horák <dan(a)danny.cz>
Fixes: d35339a42dd1 ("s390: add support for transactional memory")
Cc: <stable(a)vger.kernel.org> # v3.7+
Cc: Martin Schwidefsky <schwidefsky(a)de.ibm.com>
Reviewed-by: Christian Borntraeger <borntraeger(a)de.ibm.com>
Reviewed-by: Hendrik Brueckner <brueckner(a)linux.vnet.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens(a)de.ibm.com>
diff --git a/arch/s390/include/asm/switch_to.h b/arch/s390/include/asm/switch_to.h
index f6c2b5814ab0..8e6b07609ff4 100644
--- a/arch/s390/include/asm/switch_to.h
+++ b/arch/s390/include/asm/switch_to.h
@@ -36,8 +36,8 @@ static inline void restore_access_regs(unsigned int *acrs)
save_ri_cb(prev->thread.ri_cb); \
save_gs_cb(prev->thread.gs_cb); \
} \
+ update_cr_regs(next); \
if (next->mm) { \
- update_cr_regs(next); \
set_cpu_flag(CIF_FPU); \
restore_access_regs(&next->thread.acrs[0]); \
restore_ri_cb(next->thread.ri_cb, prev->thread.ri_cb); \
diff --git a/arch/s390/kernel/early.c b/arch/s390/kernel/early.c
index 389e9f61c76f..5096875f7822 100644
--- a/arch/s390/kernel/early.c
+++ b/arch/s390/kernel/early.c
@@ -238,8 +238,10 @@ static __init void detect_machine_facilities(void)
S390_lowcore.machine_flags |= MACHINE_FLAG_IDTE;
if (test_facility(40))
S390_lowcore.machine_flags |= MACHINE_FLAG_LPP;
- if (test_facility(50) && test_facility(73))
+ if (test_facility(50) && test_facility(73)) {
S390_lowcore.machine_flags |= MACHINE_FLAG_TE;
+ __ctl_set_bit(0, 55);
+ }
if (test_facility(51))
S390_lowcore.machine_flags |= MACHINE_FLAG_TLB_LC;
if (test_facility(129)) {
diff --git a/arch/s390/kernel/process.c b/arch/s390/kernel/process.c
index 080c851dd9a5..cee658e27732 100644
--- a/arch/s390/kernel/process.c
+++ b/arch/s390/kernel/process.c
@@ -86,6 +86,7 @@ int copy_thread_tls(unsigned long clone_flags, unsigned long new_stackp,
memset(&p->thread.per_user, 0, sizeof(p->thread.per_user));
memset(&p->thread.per_event, 0, sizeof(p->thread.per_event));
clear_tsk_thread_flag(p, TIF_SINGLE_STEP);
+ p->thread.per_flags = 0;
/* Initialize per thread user and system timer values */
p->thread.user_timer = 0;
p->thread.guest_timer = 0;
The skcipher_walk_aead_common function calls scatterwalk_copychunks on
the input and output walks to skip the associated data. If the AD end
at an SG list entry boundary, then after these calls the walks will
still be pointing to the end of the skipped region.
These offsets are later checked for alignment in skcipher_walk_next,
so the skcipher_walk may detect the alignment incorrectly.
This patch fixes it by calling scatterwalk_done after the copychunks
calls to ensure that the offsets refer to the right SG list entry.
Fixes: b286d8b1a690 ("crypto: skcipher - Add skcipher walk interface")
Cc: <stable(a)vger.kernel.org>
Signed-off-by: Ondrej Mosnacek <omosnacek(a)gmail.com>
---
crypto/skcipher.c | 3 +++
1 file changed, 3 insertions(+)
diff --git a/crypto/skcipher.c b/crypto/skcipher.c
index 4faa0fd53b0c..6c45ed536664 100644
--- a/crypto/skcipher.c
+++ b/crypto/skcipher.c
@@ -517,6 +517,9 @@ static int skcipher_walk_aead_common(struct skcipher_walk *walk,
scatterwalk_copychunks(NULL, &walk->in, req->assoclen, 2);
scatterwalk_copychunks(NULL, &walk->out, req->assoclen, 2);
+ scatterwalk_done(&walk->in, 0, walk->total);
+ scatterwalk_done(&walk->out, 0, walk->total);
+
walk->iv = req->iv;
walk->oiv = req->iv;
--
2.14.1
From: Rui Hua <huarui.dev(a)gmail.com>
When we send a read request and hit the clean data in cache device, there
is a situation called cache read race in bcache(see the commit in the tail
of cache_look_up(), the following explaination just copy from there):
The bucket we're reading from might be reused while our bio is in flight,
and we could then end up reading the wrong data. We guard against this
by checking (in bch_cache_read_endio()) if the pointer is stale again;
if so, we treat it as an error (s->iop.error = -EINTR) and reread from
the backing device (but we don't pass that error up anywhere)
It should be noted that cache read race happened under normal
circumstances, not the circumstance when SSD failed, it was counted
and shown in /sys/fs/bcache/XXX/internal/cache_read_races.
Without this patch, when we use writeback mode, we will never reread from
the backing device when cache read race happened, until the whole cache
device is clean, because the condition
(s->recoverable && (dc && !atomic_read(&dc->has_dirty))) is false in
cached_dev_read_error(). In this situation, the s->iop.error(= -EINTR)
will be passed up, at last, user will receive -EINTR when it's bio end,
this is not suitable, and wield to up-application.
In this patch, we use s->read_dirty_data to judge whether the read
request hit dirty data in cache device, it is safe to reread data from
the backing device when the read request hit clean data. This can not
only handle cache read race, but also recover data when failed read
request from cache device.
[edited by mlyle to fix up whitespace, commit log title, comment
spelling]
Fixes: d59b23795933 ("bcache: only permit to recovery read error when cache device is clean")
Cc: <stable(a)vger.kernel.org> # 4.14
Signed-off-by: Hua Rui <huarui.dev(a)gmail.com>
Reviewed-by: Michael Lyle <mlyle(a)lyle.org>
Reviewed-by: Coly Li <colyli(a)suse.de>
Signed-off-by: Michael Lyle <mlyle(a)lyle.org>
---
drivers/md/bcache/request.c | 13 ++++++-------
1 file changed, 6 insertions(+), 7 deletions(-)
diff --git a/drivers/md/bcache/request.c b/drivers/md/bcache/request.c
index 3a7aed7282b2..643c3021624f 100644
--- a/drivers/md/bcache/request.c
+++ b/drivers/md/bcache/request.c
@@ -708,16 +708,15 @@ static void cached_dev_read_error(struct closure *cl)
{
struct search *s = container_of(cl, struct search, cl);
struct bio *bio = &s->bio.bio;
- struct cached_dev *dc = container_of(s->d, struct cached_dev, disk);
/*
- * If cache device is dirty (dc->has_dirty is non-zero), then
- * recovery a failed read request from cached device may get a
- * stale data back. So read failure recovery is only permitted
- * when cache device is clean.
+ * If read request hit dirty data (s->read_dirty_data is true),
+ * then recovery a failed read request from cached device may
+ * get a stale data back. So read failure recovery is only
+ * permitted when read request hit clean data in cache device,
+ * or when cache read race happened.
*/
- if (s->recoverable &&
- (dc && !atomic_read(&dc->has_dirty))) {
+ if (s->recoverable && !s->read_dirty_data) {
/* Retry from the backing device: */
trace_bcache_read_retry(s->orig_bio);
--
2.14.1