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Pull libata fixes from Damien Le Moal:
"Two fixes for this cycle:
- Fix a null pointer dereference in ahci-platform driver (from Hai)
- Fix uninitialized variables in pata_legacy driver (from Dan)"
* tag 'libata-5.15-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/dlemoal/libata:
ata: ahci_platform: fix null-ptr-deref in ahci_platform_enable_regulators()
pata_legacy: fix a couple uninitialized variable bugs
Pull block fixes from Jens Axboe:
"Bigger than usual for this point in time, the majority is fixing some
issues around BDI lifetimes with the move from the request_queue to
the disk in this release. In detail:
- Series on draining fs IO for del_gendisk() (Christoph)
- NVMe pull request via Christoph:
- fix the abort command id (Keith Busch)
- nvme: fix per-namespace chardev deletion (Adam Manzanares)
- brd locking scope fix (Tetsuo)
- BFQ fix (Paolo)"
* tag 'block-5.15-2021-10-17' of git://git.kernel.dk/linux-block:
block, bfq: reset last_bfqq_created on group change
block: warn when putting the final reference on a registered disk
brd: reduce the brd_devices_mutex scope
kyber: avoid q->disk dereferences in trace points
block: keep q_usage_counter in atomic mode after del_gendisk
block: drain file system I/O on del_gendisk
block: split bio_queue_enter from blk_queue_enter
block: factor out a blk_try_enter_queue helper
block: call submit_bio_checks under q_usage_counter
nvme: fix per-namespace chardev deletion
block/rnbd-clt-sysfs: fix a couple uninitialized variable bugs
nvme-pci: Fix abort command id
I got a null-ptr-deref report:
KASAN: null-ptr-deref in range [0x0000000000000090-0x0000000000000097]
...
RIP: 0010:regulator_enable+0x84/0x260
...
Call Trace:
ahci_platform_enable_regulators+0xae/0x320
ahci_platform_enable_resources+0x1a/0x120
ahci_probe+0x4f/0x1b9
platform_probe+0x10b/0x280
...
entry_SYSCALL_64_after_hwframe+0x44/0xae
If devm_regulator_get() in ahci_platform_get_resources() fails,
hpriv->phy_regulator will point to NULL, when enabling or disabling it,
null-ptr-deref will occur.
ahci_probe()
ahci_platform_get_resources()
devm_regulator_get(, "phy") // failed, let phy_regulator = NULL
ahci_platform_enable_resources()
ahci_platform_enable_regulators()
regulator_enable(hpriv->phy_regulator) // null-ptr-deref
commit 962399bb7fbf ("ata: libahci_platform: Fix regulator_get_optional()
misuse") replaces devm_regulator_get_optional() with devm_regulator_get(),
but PHY regulator omits to delete "hpriv->phy_regulator = NULL;" like AHCI.
Delete it like AHCI regulator to fix this bug.
Fixes: commit 962399bb7fbf ("ata: libahci_platform: Fix regulator_get_optional() misuse")
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Wang Hai <wanghai38@huawei.com>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com>
Pull io_uring fix from Jens Axboe:
"Just a single fix for a wrong condition for grabbing a lock, a
regression in this merge window"
* tag 'io_uring-5.15-2021-10-17' of git://git.kernel.dk/linux-block:
io_uring: fix wrong condition to grab uring lock
Since commit 430a67f9d616 ("block, bfq: merge bursts of newly-created
queues"), BFQ maintains a per-group pointer to the last bfq_queue
created. If such a queue, say bfqq, happens to move to a different
group, then bfqq is no more a valid last bfq_queue created for its
previous group. That pointer must then be cleared. Not resetting such
a pointer may also cause UAF, if bfqq happens to also be freed after
being moved to a different group. This commit performs this missing
reset. As such it fixes commit 430a67f9d616 ("block, bfq: merge bursts
of newly-created queues").
Such a missing reset is most likely the cause of the crash reported in [1].
With some analysis, we found that this crash was due to the
above UAF. And such UAF did go away with this commit applied [1].
Anyway, before this commit, that crash happened to be triggered in
conjunction with commit 2d52c58b9c9b ("block, bfq: honor already-setup
queue merges"). The latter was then reverted by commit ebc69e897e17
("Revert "block, bfq: honor already-setup queue merges""). Yet commit
2d52c58b9c9b ("block, bfq: honor already-setup queue merges") contains
no error related with the above UAF, and can then be restored.
[1] https://bugzilla.kernel.org/show_bug.cgi?id=214503
Fixes: 430a67f9d616 ("block, bfq: merge bursts of newly-created queues")
Tested-by: Grzegorz Kowal <custos.mentis@gmail.com>
Signed-off-by: Paolo Valente <paolo.valente@linaro.org>
Link: https://lore.kernel.org/r/20211015144336.45894-2-paolo.valente@linaro.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
The last byte of "pad" is used without being initialized.
Fixes: 55dba3120fbc ("libata: update ->data_xfer hook for ATAPI")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com>
Pull virtio fixes from Michael Tsirkin:
"Fixes up some issues in rc5"
* tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost:
vhost-vdpa: Fix the wrong input in config_cb
VDUSE: fix documentation underline warning
Revert "virtio-blk: Add validation for block size in config space"
vhost_vdpa: unset vq irq before freeing irq
virtio: write back F_VERSION_1 before validate
Grab uring lock when we are in io-worker rather than in the original
or system-wq context since we already hold it in these two situation.
Signed-off-by: Hao Xu <haoxu@linux.alibaba.com>
Fixes: b66ceaf324b3 ("io_uring: move iopoll reissue into regular IO path")
Link: https://lore.kernel.org/r/20211014140400.50235-1-haoxu@linux.alibaba.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Warn when the last reference on a live disk is put without calling
del_gendisk first. There are some BDI related bug reports that look
like a case of this, so make sure we have the proper instrumentation
to catch it.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20211014130231.1468538-1-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Pull powerpc fixes from Michael Ellerman:
- Fix a bug where guests on P9 with interrupts passed through could get
stuck in synchronize_irq().
- Fix a bug in KVM on P8 where secondary threads entering a guest would
write outside their allocated stack.
- Fix a bug in KVM on P8 where secondary threads could confuse the host
offline code and cause the guest or host to crash.
Thanks to Cédric Le Goater.
* tag 'powerpc-5.15-4' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
KVM: PPC: Book3S HV: Make idle_kvm_start_guest() return 0 if it went to guest
KVM: PPC: Book3S HV: Fix stack handling in idle_kvm_start_guest()
powerpc/xive: Discard disabled interrupts in get_irqchip_state()
Fix the wrong input in for config_cb. In function vhost_vdpa_config_cb,
the input cb.private was used as struct vhost_vdpa, so the input was
wrong here, fix this issue
Fixes: 776f395004d8 ("vhost_vdpa: Support config interrupt in vdpa")
Signed-off-by: Cindy Lu <lulu@redhat.com>
Link: https://lore.kernel.org/r/20210929090933.20465-1-lulu@redhat.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
We have never supported fasync properly, it would only fire when there
is something polling io_uring making it useless. The original support came
in through the initial io_uring merge for 5.1. Since it's broken and
nobody has reported it, get rid of the fasync bits.
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/2f7ca3d344d406d34fa6713824198915c41cea86.1633080236.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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