Commit ea8c5356d390 ("bcache: set max writeback rate when I/O request
is idle") changes struct bch_ratelimit member rate from uint32_t to
atomic_long_t and uses atomic_long_set() in drivers/md/bcache/sysfs.c
to set new writeback rate, after the input is converted from memory
buf to long int by sysfs_strtoul_clamp().
The above change has a problem because there is an implicit return
inside sysfs_strtoul_clamp() so the following atomic_long_set()
won't be called. This error is detected by 0day system with following
snipped smatch warnings:
drivers/md/bcache/sysfs.c:271 __cached_dev_store() error: uninitialized
symbol 'v'.
270 sysfs_strtoul_clamp(writeback_rate, v, 1, INT_MAX);
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
@271 atomic_long_set(&dc->writeback_rate.rate, v);
This patch fixes the above error by using strtoul_safe_clamp() to
convert the input buffer into a long int type result.
Fixes: Commit ea8c5356d390 ("bcache: set max writeback rate when I/O request is idle")
Signed-off-by: Coly Li <colyli(a)suse.de>
Cc: stable(a)vger.kernel.org #4.16+
Cc: Kai Krakow <kai(a)kaishome.de>
Cc: Stefan Priebe <s.priebe(a)profihost.ag>
---
drivers/md/bcache/sysfs.c | 13 ++++++++++---
1 file changed, 10 insertions(+), 3 deletions(-)
diff --git a/drivers/md/bcache/sysfs.c b/drivers/md/bcache/sysfs.c
index 543b06408321..150cf4f4cf74 100644
--- a/drivers/md/bcache/sysfs.c
+++ b/drivers/md/bcache/sysfs.c
@@ -267,10 +267,17 @@ STORE(__cached_dev)
sysfs_strtoul_clamp(writeback_percent, dc->writeback_percent, 0, 40);
if (attr == &sysfs_writeback_rate) {
- int v;
+ ssize_t ret;
+ long int v = atomic_long_read(&dc->writeback_rate.rate);
+
+ ret = strtoul_safe_clamp(buf, v, 1, INT_MAX);
- sysfs_strtoul_clamp(writeback_rate, v, 1, INT_MAX);
- atomic_long_set(&dc->writeback_rate.rate, v);
+ if (!ret) {
+ atomic_long_set(&dc->writeback_rate.rate, v);
+ ret = size;
+ }
+
+ return ret;
}
sysfs_strtoul_clamp(writeback_rate_update_seconds,
--
2.18.0
The patch titled
Subject: zram-remove-bd_cap_synchronous_io-with-writeback-feature-v2
has been removed from the -mm tree. Its filename was
zram-remove-bd_cap_synchronous_io-with-writeback-feature-v2.patch
This patch was dropped because it was folded into zram-remove-bd_cap_synchronous_io-with-writeback-feature.patch
------------------------------------------------------
From: Minchan Kim <minchan(a)kernel.org>
Subject: zram-remove-bd_cap_synchronous_io-with-writeback-feature-v2
- description correction - Andrew
- add comment about removing BDI_CAP_SYNCHRONOUS_IO
Link: https://lore.kernel.org/lkml/0516ae2d-b0fd-92c5-aa92-112ba7bd32fc@contabo.d…
Link: http://lkml.kernel.org/r/20180802051112.86174-1-minchan@kernel.org
Link: http://lkml.kernel.org/r/20180805233722.217347-1-minchan@kernel.org
Signed-off-by: Minchan Kim <minchan(a)kernel.org>
Reported-by: Tino Lehnig <tino.lehnig(a)contabo.de>
Tested-by: Tino Lehnig <tino.lehnig(a)contabo.de>
Cc: Sergey Senozhatsky <sergey.senozhatsky.work(a)gmail.com>
Cc: Jens Axboe <axboe(a)kernel.dk>
Cc: <stable(a)vger.kernel.org> [4.15+]
Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org>
---
diff -puN drivers/block/zram/zram_drv.c~zram-remove-bd_cap_synchronous_io-with-writeback-feature-v2 drivers/block/zram/zram_drv.c
--- a/drivers/block/zram/zram_drv.c~zram-remove-bd_cap_synchronous_io-with-writeback-feature-v2
+++ a/drivers/block/zram/zram_drv.c
@@ -401,6 +401,16 @@ static ssize_t backing_dev_store(struct
zram->backing_dev = backing_dev;
zram->bitmap = bitmap;
zram->nr_pages = nr_pages;
+ /*
+ * With writeback feature, zram does asynchronous IO so it's no longer
+ * synchronous device so let's remove synchronous io flag. Othewise,
+ * upper layer(e.g., swap) could wait IO completion rather than
+ * (submit and return), which will cause system sluggish.
+ * Furthermore, when the IO function returns(e.g., swap_readpage),
+ * upper layer expects IO was done so it could deallocate the page
+ * freely but in fact, IO is going on so finally could cause
+ * use-after-free when the IO is really done.
+ */
zram->disk->queue->backing_dev_info->capabilities &=
~BDI_CAP_SYNCHRONOUS_IO;
up_write(&zram->init_lock);
_
Patches currently in -mm which might be from minchan(a)kernel.org are
zram-remove-bd_cap_synchronous_io-with-writeback-feature.patch
The patch titled
Subject: reiserfs: fix broken xattr handling (heap corruption, bad retval)
has been added to the -mm tree. Its filename is
reiserfs-fix-broken-xattr-handling-heap-corruption-bad-retval.patch
This patch should soon appear at
http://ozlabs.org/~akpm/mmots/broken-out/reiserfs-fix-broken-xattr-handling…
and later at
http://ozlabs.org/~akpm/mmotm/broken-out/reiserfs-fix-broken-xattr-handling…
Before you just go and hit "reply", please:
a) Consider who else should be cc'ed
b) Prefer to cc a suitable mailing list as well
c) Ideally: find the original patch on the mailing list and do a
reply-to-all to that, adding suitable additional cc's
*** Remember to use Documentation/process/submit-checklist.rst when testing your code ***
The -mm tree is included into linux-next and is updated
there every 3-4 working days
------------------------------------------------------
From: Jann Horn <jannh(a)google.com>
Subject: reiserfs: fix broken xattr handling (heap corruption, bad retval)
This fixes the following issues:
- When a buffer size is supplied to reiserfs_listxattr() such that each
individual name fits, but the concatenation of all names doesn't fit,
reiserfs_listxattr() overflows the supplied buffer. This leads to a
kernel heap overflow (verified using KASAN) followed by an out-of-bounds
usercopy and is therefore a security bug.
- When a buffer size is supplied to reiserfs_listxattr() such that a
name doesn't fit, -ERANGE should be returned. But reiserfs instead just
truncates the list of names; I have verified that if the only xattr on a
file has a longer name than the supplied buffer length, listxattr()
incorrectly returns zero.
With my patch applied, -ERANGE is returned in both cases and the memory
corruption doesn't happen anymore.
Credit for making me clean this code up a bit goes to Al Viro, who pointed
out that the ->actor calling convention is suboptimal and should be
changed.
Link: http://lkml.kernel.org/r/20180802151539.5373-1-jannh@google.com
Fixes: 48b32a3553a5 ("reiserfs: use generic xattr handlers")
Signed-off-by: Jann Horn <jannh(a)google.com>
Cc: Jeff Mahoney <jeffm(a)suse.com>
Cc: Eric Biggers <ebiggers(a)google.com>
Cc: Al Viro <viro(a)zeniv.linux.org.uk>
Cc: <stable(a)vger.kernel.org>
Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org>
---
fs/reiserfs/xattr.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)
--- a/fs/reiserfs/xattr.c~reiserfs-fix-broken-xattr-handling-heap-corruption-bad-retval
+++ a/fs/reiserfs/xattr.c
@@ -792,8 +792,10 @@ static int listxattr_filler(struct dir_c
return 0;
size = namelen + 1;
if (b->buf) {
- if (size > b->size)
+ if (b->pos + size > b->size) {
+ b->pos = -ERANGE;
return -ERANGE;
+ }
memcpy(b->buf + b->pos, name, namelen);
b->buf[b->pos + namelen] = 0;
}
_
Patches currently in -mm which might be from jannh(a)google.com are
reiserfs-fix-broken-xattr-handling-heap-corruption-bad-retval.patch
fork-dont-copy-inconsistent-signal-handler-state-to-child.patch
It's true we can't resume the device from poll workers in
nouveau_connector_detect(). We can however, prevent the autosuspend
timer from elapsing immediately if it hasn't already without risking any
sort of deadlock with the runtime suspend/resume operations. So do that
instead of entirely avoiding grabbing a power reference.
Signed-off-by: Lyude Paul <lyude(a)redhat.com>
Cc: stable(a)vger.kernel.org
Cc: Lukas Wunner <lukas(a)wunner.de>
Cc: Karol Herbst <karolherbst(a)gmail.com>
---
drivers/gpu/drm/nouveau/nouveau_connector.c | 20 +++++++++++---------
1 file changed, 11 insertions(+), 9 deletions(-)
diff --git a/drivers/gpu/drm/nouveau/nouveau_connector.c b/drivers/gpu/drm/nouveau/nouveau_connector.c
index 2a45b4c2ceb0..010d6db14cba 100644
--- a/drivers/gpu/drm/nouveau/nouveau_connector.c
+++ b/drivers/gpu/drm/nouveau/nouveau_connector.c
@@ -572,12 +572,16 @@ nouveau_connector_detect(struct drm_connector *connector, bool force)
nv_connector->edid = NULL;
}
- /* Outputs are only polled while runtime active, so acquiring a
- * runtime PM ref here is unnecessary (and would deadlock upon
- * runtime suspend because it waits for polling to finish).
+ /* Outputs are only polled while runtime active, so resuming the
+ * device here is unnecessary (and would deadlock upon runtime suspend
+ * because it waits for polling to finish). We do however, want to
+ * prevent the autosuspend timer from elapsing during this operation
+ * if possible.
*/
- if (!drm_kms_helper_is_poll_worker()) {
- ret = pm_runtime_get_sync(connector->dev->dev);
+ if (drm_kms_helper_is_poll_worker()) {
+ pm_runtime_get_noresume(dev->dev);
+ } else {
+ ret = pm_runtime_get_sync(dev->dev);
if (ret < 0 && ret != -EACCES)
return conn_status;
}
@@ -655,10 +659,8 @@ nouveau_connector_detect(struct drm_connector *connector, bool force)
out:
- if (!drm_kms_helper_is_poll_worker()) {
- pm_runtime_mark_last_busy(connector->dev->dev);
- pm_runtime_put_autosuspend(connector->dev->dev);
- }
+ pm_runtime_mark_last_busy(dev->dev);
+ pm_runtime_put_autosuspend(dev->dev);
return conn_status;
}
--
2.17.1
It's not necessary to call these before we call nouveau_do_suspend().
Ideally; we shouldn't have to call this at all here, but getting that to
work will take a bit more effort. So for the time being, just move this
call after nouveau_do_suspend() to allow us to easily be able to abort
the runtime suspend process in nouveau_do_suspend()
Signed-off-by: Lyude Paul <lyude(a)redhat.com>
Cc: stable(a)vger.kernel.org
Cc: Lukas Wunner <lukas(a)wunner.de>
Cc: Karol Herbst <karolherbst(a)gmail.com>
---
drivers/gpu/drm/nouveau/nouveau_drm.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/nouveau/nouveau_drm.c b/drivers/gpu/drm/nouveau/nouveau_drm.c
index 04f704b77a3c..5ea8fe992484 100644
--- a/drivers/gpu/drm/nouveau/nouveau_drm.c
+++ b/drivers/gpu/drm/nouveau/nouveau_drm.c
@@ -833,8 +833,8 @@ nouveau_pmops_runtime_suspend(struct device *dev)
return -EBUSY;
}
- nouveau_switcheroo_optimus_dsm();
ret = nouveau_do_suspend(drm_dev, true);
+ nouveau_switcheroo_optimus_dsm();
pci_save_state(pdev);
pci_disable_device(pdev);
pci_ignore_hotplug(pdev);
--
2.17.1
Commit efda1b5d87cb ("acpi, nfit, libnvdimm: fix / harden ars_status output length handling")
Introduced additional hardening for ambiguity in the ACPI spec for
ars_status output sizing. However, it had a couple of cases mixed up.
Where it should have been checking for (and returning) "out_field[1] -
4" it was using "out_field[1] - 8" and vice versa.
This caused a four byte discrepancy in the buffer size passed on to
the command handler, and in some cases, this caused memory corruption
like:
./daxdev-errors.sh: line 76: 24104 Aborted (core dumped) ./daxdev-errors $busdev $region
malloc(): memory corruption
Program received signal SIGABRT, Aborted.
[...]
#5 0x00007ffff7865a2e in calloc () from /lib64/libc.so.6
#6 0x00007ffff7bc2970 in ndctl_bus_cmd_new_ars_status (ars_cap=ars_cap@entry=0x6153b0) at ars.c:136
#7 0x0000000000401644 in check_ars_status (check=0x7fffffffdeb0, bus=0x604c20) at daxdev-errors.c:144
#8 test_daxdev_clear_error (region_name=<optimized out>, bus_name=<optimized out>)
at daxdev-errors.c:332
Cc: <stable(a)vger.kernel.org>
Cc: Dave Jiang <dave.jiang(a)intel.com>
Cc: Keith Busch <keith.busch(a)intel.com>
Cc: Lukasz Dorau <lukasz.dorau(a)intel.com>
Cc: Dan Williams <dan.j.williams(a)intel.com>
Fixes: efda1b5d87cb ("acpi, nfit, libnvdimm: fix / harden ars_status output length handling")
Signed-off-by: Vishal Verma <vishal.l.verma(a)intel.com>
---
drivers/nvdimm/bus.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/drivers/nvdimm/bus.c b/drivers/nvdimm/bus.c
index 27902a8799b1..8aae6dcc839f 100644
--- a/drivers/nvdimm/bus.c
+++ b/drivers/nvdimm/bus.c
@@ -812,9 +812,9 @@ u32 nd_cmd_out_size(struct nvdimm *nvdimm, int cmd,
* overshoots the remainder by 4 bytes, assume it was
* including 'status'.
*/
- if (out_field[1] - 8 == remainder)
+ if (out_field[1] - 4 == remainder)
return remainder;
- return out_field[1] - 4;
+ return out_field[1] - 8;
} else if (cmd == ND_CMD_CALL) {
struct nd_cmd_pkg *pkg = (struct nd_cmd_pkg *) in_field;
--
2.14.4