This is a note to let you know that I've just added the patch titled
fscache: Fix the default for fscache_maybe_release_page()
to the 4.14-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:
fscache-fix-the-default-for-fscache_maybe_release_page.patch
and it can be found in the queue-4.14 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 98801506552593c9b8ac11021b0cdad12cab4f6b Mon Sep 17 00:00:00 2001
From: David Howells <dhowells(a)redhat.com>
Date: Tue, 2 Jan 2018 10:02:19 +0000
Subject: fscache: Fix the default for fscache_maybe_release_page()
From: David Howells <dhowells(a)redhat.com>
commit 98801506552593c9b8ac11021b0cdad12cab4f6b upstream.
Fix the default for fscache_maybe_release_page() for when the cookie isn't
valid or the page isn't cached. It mustn't return false as that indicates
the page cannot yet be freed.
The problem with the default is that if, say, there's no cache, but a
network filesystem's pages are using up almost all the available memory, a
system can OOM because the filesystem ->releasepage() op will not allow
them to be released as fscache_maybe_release_page() incorrectly prevents
it.
This can be tested by writing a sequence of 512MiB files to an AFS mount.
It does not affect NFS or CIFS because both of those wrap the call in a
check of PG_fscache and it shouldn't bother Ceph as that only has
PG_private set whilst writeback is in progress. This might be an issue for
9P, however.
Note that the pages aren't entirely stuck. Removing a file or unmounting
will clear things because that uses ->invalidatepage() instead.
Fixes: 201a15428bd5 ("FS-Cache: Handle pages pending storage that get evicted under OOM conditions")
Reported-by: Marc Dionne <marc.dionne(a)auristor.com>
Signed-off-by: David Howells <dhowells(a)redhat.com>
Reviewed-by: Jeff Layton <jlayton(a)redhat.com>
Acked-by: Al Viro <viro(a)zeniv.linux.org.uk>
Tested-by: Marc Dionne <marc.dionne(a)auristor.com>
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
---
include/linux/fscache.h | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
--- a/include/linux/fscache.h
+++ b/include/linux/fscache.h
@@ -755,7 +755,7 @@ bool fscache_maybe_release_page(struct f
{
if (fscache_cookie_valid(cookie) && PageFsCache(page))
return __fscache_maybe_release_page(cookie, page, gfp);
- return false;
+ return true;
}
/**
Patches currently in stable-queue which might be from dhowells(a)redhat.com are
queue-4.14/fscache-fix-the-default-for-fscache_maybe_release_page.patch
This is a note to let you know that I've just added the patch titled
kernel/acct.c: fix the acct->needcheck check in check_free_space()
to the 3.18-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:
kernel-acct.c-fix-the-acct-needcheck-check-in-check_free_space.patch
and it can be found in the queue-3.18 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 4d9570158b6260f449e317a5f9ed030c2504a615 Mon Sep 17 00:00:00 2001
From: Oleg Nesterov <oleg(a)redhat.com>
Date: Thu, 4 Jan 2018 16:17:49 -0800
Subject: kernel/acct.c: fix the acct->needcheck check in check_free_space()
From: Oleg Nesterov <oleg(a)redhat.com>
commit 4d9570158b6260f449e317a5f9ed030c2504a615 upstream.
As Tsukada explains, the time_is_before_jiffies(acct->needcheck) check
is very wrong, we need time_is_after_jiffies() to make sys_acct() work.
Ignoring the overflows, the code should "goto out" if needcheck >
jiffies, while currently it checks "needcheck < jiffies" and thus in the
likely case check_free_space() does nothing until jiffies overflow.
In particular this means that sys_acct() is simply broken, acct_on()
sets acct->needcheck = jiffies and expects that check_free_space()
should set acct->active = 1 after the free-space check, but this won't
happen if jiffies increments in between.
This was broken by commit 32dc73086015 ("get rid of timer in
kern/acct.c") in 2011, then another (correct) commit 795a2f22a8ea
("acct() should honour the limits from the very beginning") made the
problem more visible.
Link: http://lkml.kernel.org/r/20171213133940.GA6554@redhat.com
Fixes: 32dc73086015 ("get rid of timer in kern/acct.c")
Reported-by: TSUKADA Koutaro <tsukada(a)ascade.co.jp>
Suggested-by: TSUKADA Koutaro <tsukada(a)ascade.co.jp>
Signed-off-by: Oleg Nesterov <oleg(a)redhat.com>
Cc: Al Viro <viro(a)zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds(a)linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
---
kernel/acct.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
--- a/kernel/acct.c
+++ b/kernel/acct.c
@@ -96,7 +96,7 @@ static int check_free_space(struct bsd_a
{
struct kstatfs sbuf;
- if (time_is_before_jiffies(acct->needcheck))
+ if (time_is_after_jiffies(acct->needcheck))
goto out;
/* May block */
Patches currently in stable-queue which might be from oleg(a)redhat.com are
queue-3.18/kernel-acct.c-fix-the-acct-needcheck-check-in-check_free_space.patch
This is a note to let you know that I've just added the patch titled
fscache: Fix the default for fscache_maybe_release_page()
to the 3.18-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:
fscache-fix-the-default-for-fscache_maybe_release_page.patch
and it can be found in the queue-3.18 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 98801506552593c9b8ac11021b0cdad12cab4f6b Mon Sep 17 00:00:00 2001
From: David Howells <dhowells(a)redhat.com>
Date: Tue, 2 Jan 2018 10:02:19 +0000
Subject: fscache: Fix the default for fscache_maybe_release_page()
From: David Howells <dhowells(a)redhat.com>
commit 98801506552593c9b8ac11021b0cdad12cab4f6b upstream.
Fix the default for fscache_maybe_release_page() for when the cookie isn't
valid or the page isn't cached. It mustn't return false as that indicates
the page cannot yet be freed.
The problem with the default is that if, say, there's no cache, but a
network filesystem's pages are using up almost all the available memory, a
system can OOM because the filesystem ->releasepage() op will not allow
them to be released as fscache_maybe_release_page() incorrectly prevents
it.
This can be tested by writing a sequence of 512MiB files to an AFS mount.
It does not affect NFS or CIFS because both of those wrap the call in a
check of PG_fscache and it shouldn't bother Ceph as that only has
PG_private set whilst writeback is in progress. This might be an issue for
9P, however.
Note that the pages aren't entirely stuck. Removing a file or unmounting
will clear things because that uses ->invalidatepage() instead.
Fixes: 201a15428bd5 ("FS-Cache: Handle pages pending storage that get evicted under OOM conditions")
Reported-by: Marc Dionne <marc.dionne(a)auristor.com>
Signed-off-by: David Howells <dhowells(a)redhat.com>
Reviewed-by: Jeff Layton <jlayton(a)redhat.com>
Acked-by: Al Viro <viro(a)zeniv.linux.org.uk>
Tested-by: Marc Dionne <marc.dionne(a)auristor.com>
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
---
include/linux/fscache.h | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
--- a/include/linux/fscache.h
+++ b/include/linux/fscache.h
@@ -764,7 +764,7 @@ bool fscache_maybe_release_page(struct f
{
if (fscache_cookie_valid(cookie) && PageFsCache(page))
return __fscache_maybe_release_page(cookie, page, gfp);
- return false;
+ return true;
}
/**
Patches currently in stable-queue which might be from dhowells(a)redhat.com are
queue-3.18/fscache-fix-the-default-for-fscache_maybe_release_page.patch
This is a note to let you know that I've just added the patch titled
crypto: n2 - cure use after free
to the 3.18-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:
crypto-n2-cure-use-after-free.patch
and it can be found in the queue-3.18 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 203f45003a3d03eea8fa28d74cfc74c354416fdb Mon Sep 17 00:00:00 2001
From: Jan Engelhardt <jengelh(a)inai.de>
Date: Tue, 19 Dec 2017 19:09:07 +0100
Subject: crypto: n2 - cure use after free
From: Jan Engelhardt <jengelh(a)inai.de>
commit 203f45003a3d03eea8fa28d74cfc74c354416fdb upstream.
queue_cache_init is first called for the Control Word Queue
(n2_crypto_probe). At that time, queue_cache[0] is NULL and a new
kmem_cache will be allocated. If the subsequent n2_register_algs call
fails, the kmem_cache will be released in queue_cache_destroy, but
queue_cache_init[0] is not set back to NULL.
So when the Module Arithmetic Unit gets probed next (n2_mau_probe),
queue_cache_init will not allocate a kmem_cache again, but leave it
as its bogus value, causing a BUG() to trigger when queue_cache[0] is
eventually passed to kmem_cache_zalloc:
n2_crypto: Found N2CP at /virtual-devices@100/n2cp@7
n2_crypto: Registered NCS HVAPI version 2.0
called queue_cache_init
n2_crypto: md5 alg registration failed
n2cp f028687c: /virtual-devices@100/n2cp@7: Unable to register algorithms.
called queue_cache_destroy
n2cp: probe of f028687c failed with error -22
n2_crypto: Found NCP at /virtual-devices@100/ncp@6
n2_crypto: Registered NCS HVAPI version 2.0
called queue_cache_init
kernel BUG at mm/slab.c:2993!
Call Trace:
[0000000000604488] kmem_cache_alloc+0x1a8/0x1e0
(inlined) kmem_cache_zalloc
(inlined) new_queue
(inlined) spu_queue_setup
(inlined) handle_exec_unit
[0000000010c61eb4] spu_mdesc_scan+0x1f4/0x460 [n2_crypto]
[0000000010c62b80] n2_mau_probe+0x100/0x220 [n2_crypto]
[000000000084b174] platform_drv_probe+0x34/0xc0
Signed-off-by: Jan Engelhardt <jengelh(a)inai.de>
Acked-by: David S. Miller <davem(a)davemloft.net>
Signed-off-by: Herbert Xu <herbert(a)gondor.apana.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
---
drivers/crypto/n2_core.c | 3 +++
1 file changed, 3 insertions(+)
--- a/drivers/crypto/n2_core.c
+++ b/drivers/crypto/n2_core.c
@@ -1641,6 +1641,7 @@ static int queue_cache_init(void)
CWQ_ENTRY_SIZE, 0, NULL);
if (!queue_cache[HV_NCS_QTYPE_CWQ - 1]) {
kmem_cache_destroy(queue_cache[HV_NCS_QTYPE_MAU - 1]);
+ queue_cache[HV_NCS_QTYPE_MAU - 1] = NULL;
return -ENOMEM;
}
return 0;
@@ -1650,6 +1651,8 @@ static void queue_cache_destroy(void)
{
kmem_cache_destroy(queue_cache[HV_NCS_QTYPE_MAU - 1]);
kmem_cache_destroy(queue_cache[HV_NCS_QTYPE_CWQ - 1]);
+ queue_cache[HV_NCS_QTYPE_MAU - 1] = NULL;
+ queue_cache[HV_NCS_QTYPE_CWQ - 1] = NULL;
}
static int spu_queue_register(struct spu_queue *p, unsigned long q_type)
Patches currently in stable-queue which might be from jengelh(a)inai.de are
queue-3.18/crypto-n2-cure-use-after-free.patch
This is a note to let you know that I've just added the patch titled
sunxi-rsb: Include OF based modalias in device uevent
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:
sunxi-rsb-include-of-based-modalias-in-device-uevent.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 e2bf801ecd4e62222a46d1ba9e57e710171d29c1 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Stefan=20Br=C3=BCns?= <stefan.bruens(a)rwth-aachen.de>
Date: Mon, 27 Nov 2017 20:05:34 +0100
Subject: sunxi-rsb: Include OF based modalias in device uevent
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
From: Stefan Brüns <stefan.bruens(a)rwth-aachen.de>
commit e2bf801ecd4e62222a46d1ba9e57e710171d29c1 upstream.
Include the OF-based modalias in the uevent sent when registering devices
on the sunxi RSB bus, so that user space has a chance to autoload the
kernel module for the device.
Fixes a regression caused by commit 3f241bfa60bd ("arm64: allwinner: a64:
pine64: Use dcdc1 regulator for mmc0"). When the axp20x-rsb module for
the AXP803 PMIC is built as a module, it is not loaded and the system
ends up with an disfunctional MMC controller.
Fixes: d787dcdb9c8f ("bus: sunxi-rsb: Add driver for Allwinner Reduced Serial Bus")
Acked-by: Chen-Yu Tsai <wens(a)csie.org>
Signed-off-by: Stefan Brüns <stefan.bruens(a)rwth-aachen.de>
Signed-off-by: Maxime Ripard <maxime.ripard(a)free-electrons.com>
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
---
drivers/bus/sunxi-rsb.c | 1 +
1 file changed, 1 insertion(+)
--- a/drivers/bus/sunxi-rsb.c
+++ b/drivers/bus/sunxi-rsb.c
@@ -178,6 +178,7 @@ static struct bus_type sunxi_rsb_bus = {
.match = sunxi_rsb_device_match,
.probe = sunxi_rsb_device_probe,
.remove = sunxi_rsb_device_remove,
+ .uevent = of_device_uevent_modalias,
};
static void sunxi_rsb_dev_release(struct device *dev)
Patches currently in stable-queue which might be from stefan.bruens(a)rwth-aachen.de are
queue-4.9/sunxi-rsb-include-of-based-modalias-in-device-uevent.patch
This is a note to let you know that I've just added the patch titled
nbd: fix use-after-free of rq/bio in the xmit path
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:
nbd-fix-use-after-free-of-rq-bio-in-the-xmit-path.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 429a787be6793554ee02aacc7e1f11ebcecc4453 Mon Sep 17 00:00:00 2001
From: Jens Axboe <axboe(a)fb.com>
Date: Thu, 17 Nov 2016 12:30:37 -0700
Subject: nbd: fix use-after-free of rq/bio in the xmit path
From: Jens Axboe <axboe(a)fb.com>
commit 429a787be6793554ee02aacc7e1f11ebcecc4453 upstream.
For writes, we can get a completion in while we're still iterating
the request and bio chain. If that happens, we're reading freed
memory and we can crash.
Break out after the last segment and avoid having the iterator
read freed memory.
Reviewed-by: Josef Bacik <jbacik(a)fb.com>
Signed-off-by: Jens Axboe <axboe(a)fb.com>
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
---
drivers/block/nbd.c | 32 +++++++++++++++++++++++---------
1 file changed, 23 insertions(+), 9 deletions(-)
--- a/drivers/block/nbd.c
+++ b/drivers/block/nbd.c
@@ -272,6 +272,7 @@ static int nbd_send_cmd(struct nbd_devic
int result, flags;
struct nbd_request request;
unsigned long size = blk_rq_bytes(req);
+ struct bio *bio;
u32 type;
if (req->cmd_type == REQ_TYPE_DRV_PRIV)
@@ -305,16 +306,20 @@ static int nbd_send_cmd(struct nbd_devic
return -EIO;
}
- if (type == NBD_CMD_WRITE) {
- struct req_iterator iter;
+ if (type != NBD_CMD_WRITE)
+ return 0;
+
+ flags = 0;
+ bio = req->bio;
+ while (bio) {
+ struct bio *next = bio->bi_next;
+ struct bvec_iter iter;
struct bio_vec bvec;
- /*
- * we are really probing at internals to determine
- * whether to set MSG_MORE or not...
- */
- rq_for_each_segment(bvec, req, iter) {
- flags = 0;
- if (!rq_iter_last(bvec, iter))
+
+ bio_for_each_segment(bvec, bio, iter) {
+ bool is_last = !next && bio_iter_last(bvec, iter);
+
+ if (is_last)
flags = MSG_MORE;
dev_dbg(nbd_to_dev(nbd), "request %p: sending %d bytes data\n",
cmd, bvec.bv_len);
@@ -325,7 +330,16 @@ static int nbd_send_cmd(struct nbd_devic
result);
return -EIO;
}
+ /*
+ * The completion might already have come in,
+ * so break for the last one instead of letting
+ * the iterator do it. This prevents use-after-free
+ * of the bio.
+ */
+ if (is_last)
+ break;
}
+ bio = next;
}
return 0;
}
Patches currently in stable-queue which might be from axboe(a)fb.com are
queue-4.9/nbd-fix-use-after-free-of-rq-bio-in-the-xmit-path.patch
This is a note to let you know that I've just added the patch titled
kernel/acct.c: fix the acct->needcheck check in check_free_space()
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:
kernel-acct.c-fix-the-acct-needcheck-check-in-check_free_space.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 4d9570158b6260f449e317a5f9ed030c2504a615 Mon Sep 17 00:00:00 2001
From: Oleg Nesterov <oleg(a)redhat.com>
Date: Thu, 4 Jan 2018 16:17:49 -0800
Subject: kernel/acct.c: fix the acct->needcheck check in check_free_space()
From: Oleg Nesterov <oleg(a)redhat.com>
commit 4d9570158b6260f449e317a5f9ed030c2504a615 upstream.
As Tsukada explains, the time_is_before_jiffies(acct->needcheck) check
is very wrong, we need time_is_after_jiffies() to make sys_acct() work.
Ignoring the overflows, the code should "goto out" if needcheck >
jiffies, while currently it checks "needcheck < jiffies" and thus in the
likely case check_free_space() does nothing until jiffies overflow.
In particular this means that sys_acct() is simply broken, acct_on()
sets acct->needcheck = jiffies and expects that check_free_space()
should set acct->active = 1 after the free-space check, but this won't
happen if jiffies increments in between.
This was broken by commit 32dc73086015 ("get rid of timer in
kern/acct.c") in 2011, then another (correct) commit 795a2f22a8ea
("acct() should honour the limits from the very beginning") made the
problem more visible.
Link: http://lkml.kernel.org/r/20171213133940.GA6554@redhat.com
Fixes: 32dc73086015 ("get rid of timer in kern/acct.c")
Reported-by: TSUKADA Koutaro <tsukada(a)ascade.co.jp>
Suggested-by: TSUKADA Koutaro <tsukada(a)ascade.co.jp>
Signed-off-by: Oleg Nesterov <oleg(a)redhat.com>
Cc: Al Viro <viro(a)zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds(a)linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
---
kernel/acct.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
--- a/kernel/acct.c
+++ b/kernel/acct.c
@@ -99,7 +99,7 @@ static int check_free_space(struct bsd_a
{
struct kstatfs sbuf;
- if (time_is_before_jiffies(acct->needcheck))
+ if (time_is_after_jiffies(acct->needcheck))
goto out;
/* May block */
Patches currently in stable-queue which might be from oleg(a)redhat.com are
queue-4.9/kernel-acct.c-fix-the-acct-needcheck-check-in-check_free_space.patch
This is a note to let you know that I've just added the patch titled
fscache: Fix the default for fscache_maybe_release_page()
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:
fscache-fix-the-default-for-fscache_maybe_release_page.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 98801506552593c9b8ac11021b0cdad12cab4f6b Mon Sep 17 00:00:00 2001
From: David Howells <dhowells(a)redhat.com>
Date: Tue, 2 Jan 2018 10:02:19 +0000
Subject: fscache: Fix the default for fscache_maybe_release_page()
From: David Howells <dhowells(a)redhat.com>
commit 98801506552593c9b8ac11021b0cdad12cab4f6b upstream.
Fix the default for fscache_maybe_release_page() for when the cookie isn't
valid or the page isn't cached. It mustn't return false as that indicates
the page cannot yet be freed.
The problem with the default is that if, say, there's no cache, but a
network filesystem's pages are using up almost all the available memory, a
system can OOM because the filesystem ->releasepage() op will not allow
them to be released as fscache_maybe_release_page() incorrectly prevents
it.
This can be tested by writing a sequence of 512MiB files to an AFS mount.
It does not affect NFS or CIFS because both of those wrap the call in a
check of PG_fscache and it shouldn't bother Ceph as that only has
PG_private set whilst writeback is in progress. This might be an issue for
9P, however.
Note that the pages aren't entirely stuck. Removing a file or unmounting
will clear things because that uses ->invalidatepage() instead.
Fixes: 201a15428bd5 ("FS-Cache: Handle pages pending storage that get evicted under OOM conditions")
Reported-by: Marc Dionne <marc.dionne(a)auristor.com>
Signed-off-by: David Howells <dhowells(a)redhat.com>
Reviewed-by: Jeff Layton <jlayton(a)redhat.com>
Acked-by: Al Viro <viro(a)zeniv.linux.org.uk>
Tested-by: Marc Dionne <marc.dionne(a)auristor.com>
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
---
include/linux/fscache.h | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
--- a/include/linux/fscache.h
+++ b/include/linux/fscache.h
@@ -764,7 +764,7 @@ bool fscache_maybe_release_page(struct f
{
if (fscache_cookie_valid(cookie) && PageFsCache(page))
return __fscache_maybe_release_page(cookie, page, gfp);
- return false;
+ return true;
}
/**
Patches currently in stable-queue which might be from dhowells(a)redhat.com are
queue-4.9/fscache-fix-the-default-for-fscache_maybe_release_page.patch