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Linux kernel
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Commit 41320b18a0e0 ("scsi: snic: Fix possible memory leak if device_add()
fails") fixed the memory leak caused by dev_set_name() when device_add()
failed. However, it did not consider that 'tgt' has already been released
when put_device(&tgt->dev) is called. Remove kfree(tgt) in the error path
to avoid double free of 'tgt' and move put_device(&tgt->dev) after the
removed kfree(tgt) to avoid a use-after-free.
Fixes: 41320b18a0e0 ("scsi: snic: Fix possible memory leak if device_add() fails")
Signed-off-by: Zhu Wang <wangzhu9@huawei.com>
Link: https://lore.kernel.org/r/20230819083941.164365-1-wangzhu9@huawei.com
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
The raid_component_add() function was added to the kernel tree via patch
"[SCSI] embryonic RAID class" (2005). Remove this function since it never
has had any callers in the Linux kernel. And also raid_component_release()
is only used in raid_component_add(), so it is also removed.
Signed-off-by: Zhu Wang <wangzhu9@huawei.com>
Link: https://lore.kernel.org/r/20230822015254.184270-1-wangzhu9@huawei.com
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Fixes: 04b5b5cb0136 ("scsi: core: Fix possible memory leak if device_add() fails")
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
The qunipro_g4_sel clear is also needed for new platforms with major
version > 5. Fix the version check to take this into account.
Fixes: 9c02aa24bf40 ("scsi: ufs: ufs-qcom: Clear qunipro_g4_sel for HW version major 5")
Acked-by: Manivannan Sadhasivam <mani@kernel.org>
Reviewed-by: Nitin Rawat <quic_nitirawa@quicinc.com>
Signed-off-by: Neil Armstrong <neil.armstrong@linaro.org>
Link: https://lore.kernel.org/r/20230821-topic-sm8x50-upstream-ufs-major-5-plus-v2-1-f42a4b712e58@linaro.org
Reviewed-by: "Bao D. Nguyen" <quic_nguyenb@quicinc.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
The search and wrap around logic in the ufshcd_mcq_sqe_search() function
does not work correctly when the hwq's queue depth is not a power of two
number. Correct it so that any queue depth with a positive integer value
within the supported range would work.
Signed-off-by: "Bao D. Nguyen" <quic_nguyenb@quicinc.com>
Link: https://lore.kernel.org/r/ff49c15be205135ed3ec186f3086694c02867dbd.1692149603.git.quic_nguyenb@quicinc.com
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Fixes: 8d7290348992 ("scsi: ufs: mcq: Add supporting functions for MCQ abort")
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
While performing certain power-off sequences, PCI drivers are called to
suspend and resume their underlying devices through PCI PM (power
management) interface. However the hardware does not support PCI PM
suspend/resume operations so system wide suspend/resume leads to bad MFW
(management firmware) state which causes various follow-up errors in driver
when communicating with the device/firmware.
To fix this driver implements PCI PM suspend handler to indicate
unsupported operation to the PCI subsystem explicitly, thus avoiding system
to go into suspended/standby mode.
Fixes: 61d8658b4a43 ("scsi: qedf: Add QLogic FastLinQ offload FCoE driver framework.")
Signed-off-by: Saurav Kashyap <skashyap@marvell.com>
Signed-off-by: Nilesh Javali <njavali@marvell.com>
Link: https://lore.kernel.org/r/20230807093725.46829-1-njavali@marvell.com
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
While performing certain power-off sequences, PCI drivers are called to
suspend and resume their underlying devices through PCI PM (power
management) interface. However the hardware does not support PCI PM
suspend/resume operations so system wide suspend/resume leads to bad MFW
(management firmware) state which causes various follow-up errors in driver
when communicating with the device/firmware.
To fix this driver implements PCI PM suspend handler to indicate
unsupported operation to the PCI subsystem explicitly, thus avoiding system
to go into suspended/standby mode.
Fixes: ace7f46ba5fd ("scsi: qedi: Add QLogic FastLinQ offload iSCSI driver framework.")
Signed-off-by: Nilesh Javali <njavali@marvell.com>
Link: https://lore.kernel.org/r/20230807093725.46829-2-njavali@marvell.com
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
As &qedi_percpu->p_work_lock is acquired by hard IRQ qedi_msix_handler(),
other acquisitions of the same lock under process context should disable
IRQ, otherwise deadlock could happen if the IRQ preempts the execution
while the lock is held in process context on the same CPU.
qedi_cpu_offline() is one such function which acquires the lock in process
context.
[Deadlock Scenario]
qedi_cpu_offline()
->spin_lock(&p->p_work_lock)
<irq>
->qedi_msix_handler()
->edi_process_completions()
->spin_lock_irqsave(&p->p_work_lock, flags); (deadlock here)
This flaw was found by an experimental static analysis tool I am developing
for IRQ-related deadlocks.
The tentative patch fix the potential deadlock by spin_lock_irqsave()
under process context.
Signed-off-by: Chengfeng Ye <dg573847474@gmail.com>
Link: https://lore.kernel.org/r/20230726125655.4197-1-dg573847474@gmail.com
Acked-by: Manish Rangankar <mrangankar@marvell.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
When preparing protection DIF I/O for DMA, the driver obtains reference
tags from scsi_prot_ref_tag(). Previously, there was a wrong assumption
that an all 0xffffffff value meant error and thus the driver failed the
I/O. This patch removes the evaluation code and accepts whatever the upper
layer returns.
Signed-off-by: Justin Tee <justin.tee@broadcom.com>
Link: https://lore.kernel.org/r/20230803211932.155745-1-justintee8345@gmail.com
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Should use devm_kzalloc() for struct ufs_renesas_priv because the
.initialized should be false as default.
Fixes: d69520288efd ("scsi: ufs: ufs-renesas: Add support for Renesas R-Car UFS controller")
Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Link: https://lore.kernel.org/r/20230803081812.1446282-1-yoshihiro.shimoda.uh@renesas.com
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
If device_add() returns error, the name allocated by dev_set_name() needs
be freed. As the comment of device_add() says, put_device() should be used
to give up the reference in the error path. So fix this by calling
put_device(), then the name can be freed in kobject_cleanp().
Fixes: c8806b6c9e82 ("snic: driver for Cisco SCSI HBA")
Signed-off-by: Zhu Wang <wangzhu9@huawei.com>
Acked-by: Narsimhulu Musini <nmusini@cisco.com>
Link: https://lore.kernel.org/r/20230801111421.63651-1-wangzhu9@huawei.com
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
If device_add() returns error, the name allocated by dev_set_name() needs
be freed. As the comment of device_add() says, put_device() should be used
to decrease the reference count in the error path. So fix this by calling
put_device(), then the name can be freed in kobject_cleanp().
Fixes: ee959b00c335 ("SCSI: convert struct class_device to struct device")
Signed-off-by: Zhu Wang <wangzhu9@huawei.com>
Link: https://lore.kernel.org/r/20230803020230.226903-1-wangzhu9@huawei.com
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
(lightly modified commit message mostly by Linus Torvalds)
The parsing code for /proc/scsi/scsi is disgusting and broken. We should
have just used 'sscanf()' or something simple like that, but the logic may
actually predate our kernel sscanf library routine for all I know. It
certainly predates both git and BK histories.
And we can't change it to be something sane like that now, because the
string matching at the start is done case-insensitively, and the separator
parsing between numbers isn't done at all, so *any* separator will work,
including a possible terminating NUL character.
This interface is root-only, and entirely for legacy use, so there is
absolutely no point in trying to tighten up the parsing. Because any
separator has traditionally worked, it's entirely possible that people have
used random characters rather than the suggested space.
So don't bother to try to pretty it up, and let's just make a minimal patch
that can be back-ported and we can forget about this whole sorry thing for
another two decades.
Just make it at least not read past the end of the supplied data.
Link: https://lore.kernel.org/linux-scsi/b570f5fe-cb7c-863a-6ed9-f6774c219b88@cybernetics.com/
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Martin K Petersen <martin.petersen@oracle.com>
Cc: James Bottomley <jejb@linux.ibm.com>
Cc: Willy Tarreau <w@1wt.eu>
Cc: stable@kernel.org
Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Tony Battersby <tonyb@cybernetics.com>
Signed-off-by: Martin K Petersen <martin.petersen@oracle.com>
Add a check for the command slot value to avoid dereferencing a NULL
pointer.
Found by Linux Verification Center (linuxtesting.org) with SVACE.
Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Co-developed-by: Vladimir Telezhnikov <vtelezhnikov@astralinux.ru>
Signed-off-by: Vladimir Telezhnikov <vtelezhnikov@astralinux.ru>
Signed-off-by: Alexandra Diupina <adiupina@astralinux.ru>
Link: https://lore.kernel.org/r/20230728123521.18293-1-adiupina@astralinux.ru
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
fnic_clean_pending_aborts() was returning a non-zero value irrespective of
failure or success. This caused the caller of this function to assume that
the device reset had failed, even though it would succeed in most cases. As
a consequence, a successful device reset would escalate to host reset.
Reviewed-by: Sesidhar Baddela <sebaddel@cisco.com>
Tested-by: Karan Tilak Kumar <kartilak@cisco.com>
Signed-off-by: Karan Tilak Kumar <kartilak@cisco.com>
Link: https://lore.kernel.org/r/20230727193919.2519-1-kartilak@cisco.com
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Hyper-V provides the ability to connect Fibre Channel LUNs to the host
system and present them in a guest VM as a SCSI device. I/O to the vFC
device is handled by the storvsc driver. The storvsc driver includes a
partial integration with the FC transport implemented in the generic
portion of the Linux SCSI subsystem so that FC attributes can be displayed
in /sys. However, the partial integration means that some aspects of vFC
don't work properly. Unfortunately, a full and correct integration isn't
practical because of limitations in what Hyper-V provides to the guest.
In particular, in the context of Hyper-V storvsc, the FC transport timeout
function fc_eh_timed_out() causes a kernel panic because it can't find the
rport and dereferences a NULL pointer. The original patch that added the
call from storvsc_eh_timed_out() to fc_eh_timed_out() is faulty in this
regard.
In many cases a timeout is due to a transient condition, so the situation
can be improved by just continuing to wait like with other I/O requests
issued by storvsc, and avoiding the guaranteed panic. For a permanent
failure, continuing to wait may result in a hung thread instead of a panic,
which again may be better.
So fix the panic by removing the storvsc call to fc_eh_timed_out(). This
allows storvsc to keep waiting for a response. The change has been tested
by users who experienced a panic in fc_eh_timed_out() due to transient
timeouts, and it solves their problem.
In the future we may want to deprecate the vFC functionality in storvsc
since it can't be fully fixed. But it has current users for whom it is
working well enough, so it should probably stay for a while longer.
Fixes: 3930d7309807 ("scsi: storvsc: use default I/O timeout handler for FC devices")
Cc: stable@vger.kernel.org
Signed-off-by: Michael Kelley <mikelley@microsoft.com>
Link: https://lore.kernel.org/r/1690606764-79669-1-git-send-email-mikelley@microsoft.com
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
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