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Linux kernel
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Tom Hatskevich reported that we look up "iocp" then, in the called
functions we do a second copy_from_user() and look it up again.
The problem that could cause is:
drivers/message/fusion/mptctl.c
674 /* All of these commands require an interrupt or
675 * are unknown/illegal.
676 */
677 if ((ret = mptctl_syscall_down(iocp, nonblock)) != 0)
^^^^
We take this lock.
678 return ret;
679
680 if (cmd == MPTFWDOWNLOAD)
681 ret = mptctl_fw_download(arg);
^^^
Then the user memory changes and we look up "iocp" again but a different
one so now we are holding the incorrect lock and have a race condition.
682 else if (cmd == MPTCOMMAND)
683 ret = mptctl_mpt_command(arg);
The security impact of this bug is not as bad as it could have been
because these operations are all privileged and root already has
enormous destructive power. But it's still worth fixing.
This patch passes the "iocp" pointer to the functions to avoid the
second lookup. That deletes 100 lines of code from the driver so
it's a nice clean up as well.
Link: https://lore.kernel.org/r/20200114123414.GA7957@kadam
Reported-by: Tom Hatskevich <tom2001tom.23@gmail.com>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Commit 0ed881027690 ("scsi: storvsc: setup 1:1 mapping between hardware
queue and CPU queue") introduced a regression for disks attached to
IDE. For these disks the host VSP only offers one VMBUS channel. Setting
multiple queues can overload the VMBUS channel and result in performance
drop for high queue depth workload on system with large number of CPUs.
Fix it by leaving the number of hardware queues to 1 (default value) for
IDE disks.
Fixes: 0ed881027690 ("scsi: storvsc: setup 1:1 mapping between hardware queue and CPU queue")
Link: https://lore.kernel.org/r/1578960516-108228-1-git-send-email-longli@linuxonhyperv.com
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Long Li <longli@microsoft.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
gcc -O3 warns that some local variables are not properly initialized:
drivers/scsi/fnic/vnic_dev.c: In function 'fnic_dev_hang_notify':
drivers/scsi/fnic/vnic_dev.c:511:16: error: 'a0' is used uninitialized in this function [-Werror=uninitialized]
vdev->args[0] = *a0;
~~~~~~~~~~~~~~^~~~~
drivers/scsi/fnic/vnic_dev.c:691:6: note: 'a0' was declared here
u64 a0, a1;
^~
drivers/scsi/fnic/vnic_dev.c:512:16: error: 'a1' is used uninitialized in this function [-Werror=uninitialized]
vdev->args[1] = *a1;
~~~~~~~~~~~~~~^~~~~
drivers/scsi/fnic/vnic_dev.c:691:10: note: 'a1' was declared here
u64 a0, a1;
^~
drivers/scsi/fnic/vnic_dev.c: In function 'fnic_dev_mac_addr':
drivers/scsi/fnic/vnic_dev.c:512:16: error: 'a1' is used uninitialized in this function [-Werror=uninitialized]
vdev->args[1] = *a1;
~~~~~~~~~~~~~~^~~~~
drivers/scsi/fnic/vnic_dev.c:698:10: note: 'a1' was declared here
u64 a0, a1;
^~
Apparently the code relies on the local variables occupying adjacent memory
locations in the same order, but this is of course not guaranteed.
Use an array of two u64 variables where needed to make it work correctly.
I suspect there is also an endianness bug here, but have not digged in deep
enough to be sure.
Fixes: 5df6d737dd4b ("[SCSI] fnic: Add new Cisco PCI-Express FCoE HBA")
Fixes: mmtom ("init/Kconfig: enable -O3 for all arches")
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20200107201602.4096790-1-arnd@arndb.de
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Doing an add/remove/add on a SCSI device in an enclosure leads to an oops
caused by poisoned values in the enclosure device list pointers. The
reason is because we are keeping the enclosure device across the enclosed
device add/remove/add but the current code is doing a
device_add/device_del/device_add on it. This is the wrong thing to do in
sysfs, so fix it by not doing a device_del on the enclosure device simply
because of a hot remove of the drive in the slot.
[mkp: added missing email addresses]
Fixes: 43d8eb9cfd0a ("[SCSI] ses: add support for enclosure component hot removal")
Link: https://lore.kernel.org/r/1578532892.3852.10.camel@HansenPartnership.com
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
Reported-by: Luo Jiaxing <luojiaxing@huawei.com>
Tested-by: John Garry <john.garry@huawei.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
If an attached disk with protection information enabled is reformatted
to Type 0 the revalidation code does not clear the original protection
type and subsequent accesses will keep setting RDPROTECT/WRPROTECT.
Set the protection type to 0 if the disk reports PROT_EN=0 in READ
CAPACITY(16).
[mkp: commit desc]
Fixes: fe542396da73 ("[SCSI] sd: Ensure we correctly disable devices with unknown protection type")
Link: https://lore.kernel.org/r/1578532344-101668-1-git-send-email-chenxiang66@hisilicon.com
Signed-off-by: Xiang Chen <chenxiang66@hisilicon.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
The sector size of the block layer is 512 bytes, but integrity interval
size might be different (in case of 4K block size of the media). At the
initiator side the virtual start sector is the one that was originally
submitted by the block layer (512 bytes) for the Reftag usage. The
initiator converts the Reftag to integrity interval units and sends it to
the target. So the target virtual start sector should be calculated at
integrity interval units. prepare_fn() and complete_fn() don't remap
correctly the Reftag when using incorrect units of the virtual start
sector, which leads to the following protection error at the device:
"blk_update_request: protection error, dev sdb, sector 2048 op 0x0:(READ)
flags 0x10000 phys_seg 1 prio class 0"
To fix that, set the seed in integrity interval units.
Link: https://lore.kernel.org/r/1576078562-15240-1-git-send-email-israelr@mellanox.com
Signed-off-by: Israel Rukshin <israelr@mellanox.com>
Reviewed-by: Max Gurtovoy <maxg@mellanox.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
If cxgb4i_ddp_init() fails then cdev->cdev2ppm will be NULL, so add a check
for NULL pointer before dereferencing it.
Link: https://lore.kernel.org/r/1576676731-3068-1-git-send-email-varun@chelsio.com
Signed-off-by: Varun Prakash <varun@chelsio.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
There are spelling mistakes of asynchronous in a lpfc_printf_log message
and comments. Fix these.
Link: https://lore.kernel.org/r/20191218084301.627555-1-colin.king@canonical.com
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Reviewed-by: James Smart <james.smart@broadcom.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
A recent change appears to have moved an #endif by accident:
drivers/scsi/lpfc/lpfc_debugfs.c:5393:18: error: 'lpfc_debugfs_dumpHBASlim_open' undeclared here (not in a function); did you mean 'lpfc_debugfs_op_dumpHBASlim'?
drivers/scsi/lpfc/lpfc_debugfs.c:5394:18: error: 'lpfc_debugfs_lseek' undeclared here (not in a function); did you mean 'lpfc_debugfs_nvme_trc'?
drivers/scsi/lpfc/lpfc_debugfs.c:5395:18: error: 'lpfc_debugfs_read' undeclared here (not in a function); did you mean 'lpfc_debug_dump_q'?
drivers/scsi/lpfc/lpfc_debugfs.c:5396:18: error: 'lpfc_debugfs_release' undeclared here (not in a function); did you mean 'lpfc_debugfs_terminate'?
drivers/scsi/lpfc/lpfc_debugfs.c:5402:18: error: 'lpfc_debugfs_dumpHostSlim_open' undeclared here (not in a function); did you mean 'lpfc_debugfs_op_dumpHostSlim'?
Move it back to where it was previously.
Fixes: 95bfc6d8ad86 ("scsi: lpfc: Make FW logging dynamically configurable")
Link: https://lore.kernel.org/r/20191216131701.3125077-1-arnd@arndb.de
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: James Smart <james.smart@broadcom.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
The caller also calls _base_release_memory_pools() on error so it leads to
a number of double frees:
drivers/scsi/mpt3sas/mpt3sas_base.c:7207 mpt3sas_base_attach() warn: 'ioc->chain_dma_pool' double freed
drivers/scsi/mpt3sas/mpt3sas_base.c:7207 mpt3sas_base_attach() warn: 'ioc->hpr_lookup' double freed
drivers/scsi/mpt3sas/mpt3sas_base.c:7207 mpt3sas_base_attach() warn: 'ioc->internal_lookup' double freed
drivers/scsi/mpt3sas/mpt3sas_base.c:7207 mpt3sas_base_attach() warn: 'ioc->pcie_sgl_dma_pool' double freed
drivers/scsi/mpt3sas/mpt3sas_base.c:7207 mpt3sas_base_attach() warn: 'ioc->reply_dma_pool' double freed
drivers/scsi/mpt3sas/mpt3sas_base.c:7207 mpt3sas_base_attach() warn: 'ioc->reply_free_dma_pool' double freed
drivers/scsi/mpt3sas/mpt3sas_base.c:7207 mpt3sas_base_attach() warn: 'ioc->reply_post_free_array_dma_pool' double freed
drivers/scsi/mpt3sas/mpt3sas_base.c:7207 mpt3sas_base_attach() warn: 'ioc->reply_post_free_dma_pool' double freed
drivers/scsi/mpt3sas/mpt3sas_base.c:7207 mpt3sas_base_attach() warn: 'ioc->sense_dma_pool' double freed
Fixes: 74522a92bbf0 ("scsi: mpt3sas: Optimize I/O memory consumption in driver.")
Link: https://lore.kernel.org/r/20191203093652.gyntgvnkw2udatyc@kili.mountain
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: Sreekanth Reddy <sreekanth.reddy@broadcom.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
In iscsi_if_rx func, after receiving one request through
iscsi_if_recv_msg func, iscsi_if_send_reply will be called to try to
reply to the request in a do-while loop. If the iscsi_if_send_reply
function keeps returning -EAGAIN, a deadlock will occur.
For example, a client only send msg without calling recvmsg func, then
it will result in the watchdog soft lockup. The details are given as
follows:
sock_fd = socket(AF_NETLINK, SOCK_RAW, NETLINK_ISCSI);
retval = bind(sock_fd, (struct sock addr*) & src_addr, sizeof(src_addr);
while (1) {
state_msg = sendmsg(sock_fd, &msg, 0);
//Note: recvmsg(sock_fd, &msg, 0) is not processed here.
}
close(sock_fd);
watchdog: BUG: soft lockup - CPU#7 stuck for 22s! [netlink_test:253305] Sample time: 4000897528 ns(HZ: 250) Sample stat:
curr: user: 675503481560, nice: 321724050, sys: 448689506750, idle: 4654054240530, iowait: 40885550700, irq: 14161174020, softirq: 8104324140, st: 0
deta: user: 0, nice: 0, sys: 3998210100, idle: 0, iowait: 0, irq: 1547170, softirq: 242870, st: 0 Sample softirq:
TIMER: 992
SCHED: 8
Sample irqstat:
irq 2: delta 1003, curr: 3103802, arch_timer
CPU: 7 PID: 253305 Comm: netlink_test Kdump: loaded Tainted: G OE
Hardware name: QEMU KVM Virtual Machine, BIOS 0.0.0 02/06/2015
pstate: 40400005 (nZcv daif +PAN -UAO)
pc : __alloc_skb+0x104/0x1b0
lr : __alloc_skb+0x9c/0x1b0
sp : ffff000033603a30
x29: ffff000033603a30 x28: 00000000000002dd
x27: ffff800b34ced810 x26: ffff800ba7569f00
x25: 00000000ffffffff x24: 0000000000000000
x23: ffff800f7c43f600 x22: 0000000000480020
x21: ffff0000091d9000 x20: ffff800b34eff200
x19: ffff800ba7569f00 x18: 0000000000000000
x17: 0000000000000000 x16: 0000000000000000
x15: 0000000000000000 x14: 0001000101000100
x13: 0000000101010000 x12: 0101000001010100
x11: 0001010101010001 x10: 00000000000002dd
x9 : ffff000033603d58 x8 : ffff800b34eff400
x7 : ffff800ba7569200 x6 : ffff800b34eff400
x5 : 0000000000000000 x4 : 00000000ffffffff
x3 : 0000000000000000 x2 : 0000000000000001
x1 : ffff800b34eff2c0 x0 : 0000000000000300 Call trace:
__alloc_skb+0x104/0x1b0
iscsi_if_rx+0x144/0x12bc [scsi_transport_iscsi]
netlink_unicast+0x1e0/0x258
netlink_sendmsg+0x310/0x378
sock_sendmsg+0x4c/0x70
sock_write_iter+0x90/0xf0
__vfs_write+0x11c/0x190
vfs_write+0xac/0x1c0
ksys_write+0x6c/0xd8
__arm64_sys_write+0x24/0x30
el0_svc_common+0x78/0x130
el0_svc_handler+0x38/0x78
el0_svc+0x8/0xc
Link: https://lore.kernel.org/r/EDBAAA0BBBA2AC4E9C8B6B81DEEE1D6915E3D4D2@dggeml505-mbx.china.huawei.com
Signed-off-by: Bo Wu <wubo40@huawei.com>
Reviewed-by: Zhiqiang Liu <liuzhiqiang26@huawei.com>
Reviewed-by: Lee Duncan <lduncan@suse.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Some time ago the block layer was modified such that timeout handlers are
called from thread context instead of interrupt context. Make it safe to
run the iSCSI timeout handler in thread context. This patch fixes the
following lockdep complaint:
================================
WARNING: inconsistent lock state
5.5.1-dbg+ #11 Not tainted
--------------------------------
inconsistent {IN-SOFTIRQ-W} -> {SOFTIRQ-ON-W} usage.
kworker/7:1H/206 [HC0[0]:SC0[0]:HE1:SE1] takes:
ffff88802d9827e8 (&(&session->frwd_lock)->rlock){+.?.}, at: iscsi_eh_cmd_timed_out+0xa6/0x6d0 [libiscsi]
{IN-SOFTIRQ-W} state was registered at:
lock_acquire+0x106/0x240
_raw_spin_lock+0x38/0x50
iscsi_check_transport_timeouts+0x3e/0x210 [libiscsi]
call_timer_fn+0x132/0x470
__run_timers.part.0+0x39f/0x5b0
run_timer_softirq+0x63/0xc0
__do_softirq+0x12d/0x5fd
irq_exit+0xb3/0x110
smp_apic_timer_interrupt+0x131/0x3d0
apic_timer_interrupt+0xf/0x20
default_idle+0x31/0x230
arch_cpu_idle+0x13/0x20
default_idle_call+0x53/0x60
do_idle+0x38a/0x3f0
cpu_startup_entry+0x24/0x30
start_secondary+0x222/0x290
secondary_startup_64+0xa4/0xb0
irq event stamp: 1383705
hardirqs last enabled at (1383705): [<ffffffff81aace5c>] _raw_spin_unlock_irq+0x2c/0x50
hardirqs last disabled at (1383704): [<ffffffff81aacb98>] _raw_spin_lock_irq+0x18/0x50
softirqs last enabled at (1383690): [<ffffffffa0e2efea>] iscsi_queuecommand+0x76a/0xa20 [libiscsi]
softirqs last disabled at (1383682): [<ffffffffa0e2e998>] iscsi_queuecommand+0x118/0xa20 [libiscsi]
other info that might help us debug this:
Possible unsafe locking scenario:
CPU0
----
lock(&(&session->frwd_lock)->rlock);
<Interrupt>
lock(&(&session->frwd_lock)->rlock);
*** DEADLOCK ***
2 locks held by kworker/7:1H/206:
#0: ffff8880d57bf928 ((wq_completion)kblockd){+.+.}, at: process_one_work+0x472/0xab0
#1: ffff88802b9c7de8 ((work_completion)(&q->timeout_work)){+.+.}, at: process_one_work+0x476/0xab0
stack backtrace:
CPU: 7 PID: 206 Comm: kworker/7:1H Not tainted 5.5.1-dbg+ #11
Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
Workqueue: kblockd blk_mq_timeout_work
Call Trace:
dump_stack+0xa5/0xe6
print_usage_bug.cold+0x232/0x23b
mark_lock+0x8dc/0xa70
__lock_acquire+0xcea/0x2af0
lock_acquire+0x106/0x240
_raw_spin_lock+0x38/0x50
iscsi_eh_cmd_timed_out+0xa6/0x6d0 [libiscsi]
scsi_times_out+0xf4/0x440 [scsi_mod]
scsi_timeout+0x1d/0x20 [scsi_mod]
blk_mq_check_expired+0x365/0x3a0
bt_iter+0xd6/0xf0
blk_mq_queue_tag_busy_iter+0x3de/0x650
blk_mq_timeout_work+0x1af/0x380
process_one_work+0x56d/0xab0
worker_thread+0x7a/0x5d0
kthread+0x1bc/0x210
ret_from_fork+0x24/0x30
Fixes: 287922eb0b18 ("block: defer timeouts to a workqueue")
Cc: Christoph Hellwig <hch@lst.de>
Cc: Keith Busch <keith.busch@intel.com>
Cc: Lee Duncan <lduncan@suse.com>
Cc: Chris Leech <cleech@redhat.com>
Cc: <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20191209173457.187370-1-bvanassche@acm.org
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: Lee Duncan <lduncan@suse.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
The file name in the documentation is currently incorrect, so fix it.
Link: https://lore.kernel.org/r/fe264d62-0371-ea59-b66a-6d855290ce65@molgen.mpg.de
Fixes: 6d90615f1346 ("scsi: smartpqi: add sysfs entries")
Signed-off-by: Paul Menzel <pmenzel@molgen.mpg.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
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