kernel.git/drivers/s390/scsi, branch linux-5.7.y

scsi: zfcp: Fix use-after-free in request timeout handlers

2020-08-26T09:42:06Z

commit 2d9a2c5f581be3991ba67fa9e7497c711220ea8e upstream. Before v4.15 commit 75492a51568b ("s390/scsi: Convert timers to use timer_setup()"), we intentionally only passed zfcp_adapter as context argument to zfcp_fsf_request_timeout_handler(). Since we only trigger adapter recovery, it was unnecessary to sync against races between timeout and (late) completion. Likewise, we only passed zfcp_erp_action as context argument to zfcp_erp_timeout_handler(). Since we only wakeup an ERP action, it was unnecessary to sync against races between timeout and (late) completion. Meanwhile the timeout handlers get timer_list as context argument and do a timer-specific container-of to zfcp_fsf_req which can have been freed. Fix it by making sure that any request timeout handlers, that might just have started before del_timer(), are completed by using del_timer_sync() instead. This ensures the request free happens afterwards. Space time diagram of potential use-after-free: Basic idea is to have 2 or more pending requests whose timeouts run out at almost the same time. req 1 timeout ERP thread req 2 timeout ---------------- ---------------- --------------------------------------- zfcp_fsf_request_timeout_handler fsf_req = from_timer(fsf_req, t, timer) adapter = fsf_req->adapter zfcp_qdio_siosl(adapter) zfcp_erp_adapter_reopen(adapter,...) zfcp_erp_strategy ... zfcp_fsf_req_dismiss_all list_for_each_entry_safe zfcp_fsf_req_complete 1 del_timer 1 zfcp_fsf_req_free 1 zfcp_fsf_req_complete 2 zfcp_fsf_request_timeout_handler del_timer 2 fsf_req = from_timer(fsf_req, t, timer) zfcp_fsf_req_free 2 adapter = fsf_req->adapter ^^^^^^^ already freed Link: https://lore.kernel.org/r/20200813152856.50088-1-maier@linux.ibm.com Fixes: 75492a51568b ("s390/scsi: Convert timers to use timer_setup()") Cc: #4.15+ Suggested-by: Julian Wiedmann Reviewed-by: Julian Wiedmann Signed-off-by: Steffen Maier Signed-off-by: Martin K. Petersen Signed-off-by: Greg Kroah-Hartman

scsi: zfcp: Fix panic on ERP timeout for previously dismissed ERP action

2020-06-30T19:35:57Z

commit 936e6b85da0476dd2edac7c51c68072da9fb4ba2 upstream. Suppose that, for unrelated reasons, FSF requests on behalf of recovery are very slow and can run into the ERP timeout. In the case at hand, we did adapter recovery to a large degree. However due to the slowness a LUN open is pending so the corresponding fc_rport remains blocked. After fast_io_fail_tmo we trigger close physical port recovery for the port under which the LUN should have been opened. The new higher order port recovery dismisses the pending LUN open ERP action and dismisses the pending LUN open FSF request. Such dismissal decouples the ERP action from the pending corresponding FSF request by setting zfcp_fsf_req->erp_action to NULL (among other things) [zfcp_erp_strategy_check_fsfreq()]. If now the ERP timeout for the pending open LUN request runs out, we must not use zfcp_fsf_req->erp_action in the ERP timeout handler. This is a problem since v4.15 commit 75492a51568b ("s390/scsi: Convert timers to use timer_setup()"). Before that we intentionally only passed zfcp_erp_action as context argument to zfcp_erp_timeout_handler(). Note: The lifetime of the corresponding zfcp_fsf_req object continues until a (late) response or an (unrelated) adapter recovery. Just like the regular response path ignores dismissed requests [zfcp_fsf_req_complete() => zfcp_fsf_protstatus_eval() => return early] the ERP timeout handler now needs to ignore dismissed requests. So simply return early in the ERP timeout handler if the FSF request is marked as dismissed in its status flags. To protect against the race where zfcp_erp_strategy_check_fsfreq() dismisses and sets zfcp_fsf_req->erp_action to NULL after our previous status flag check, return early if zfcp_fsf_req->erp_action is NULL. After all, the former ERP action does not need to be woken up as that was already done as part of the dismissal above [zfcp_erp_action_dismiss()]. This fixes the following panic due to kernel page fault in IRQ context: Unable to handle kernel pointer dereference in virtual kernel address space Failing address: 0000000000000000 TEID: 0000000000000483 Fault in home space mode while using kernel ASCE. AS:000009859238c00b R2:00000e3e7ffd000b R3:00000e3e7ffcc007 S:00000e3e7ffd7000 P:000000000000013d Oops: 0004 ilc:2 [#1] SMP Modules linked in: ... CPU: 82 PID: 311273 Comm: stress Kdump: loaded Tainted: G E X ... Hardware name: IBM 8561 T01 701 (LPAR) Krnl PSW : 0404c00180000000 001fffff80549be0 (zfcp_erp_notify+0x40/0xc0 [zfcp]) R:0 T:1 IO:0 EX:0 Key:0 M:1 W:0 P:0 AS:3 CC:0 PM:0 RI:0 EA:3 Krnl GPRS: 0000000000000080 00000e3d00000000 00000000000000f0 0000000000030000 000000010028e700 000000000400a39c 000000010028e700 00000e3e7cf87e02 0000000010000000 0700098591cb67f0 0000000000000000 0000000000000000 0000033840e9a000 0000000000000000 001fffe008d6bc18 001fffe008d6bbc8 Krnl Code: 001fffff80549bd4: a7180000 lhi %r1,0 001fffff80549bd8: 4120a0f0 la %r2,240(%r10) #001fffff80549bdc: a53e0003 llilh %r3,3 >001fffff80549be0: ba132000 cs %r1,%r3,0(%r2) 001fffff80549be4: a7740037 brc 7,1fffff80549c52 001fffff80549be8: e320b0180004 lg %r2,24(%r11) 001fffff80549bee: e31020e00004 lg %r1,224(%r2) 001fffff80549bf4: 412020e0 la %r2,224(%r2) Call Trace: [<001fffff80549be0>] zfcp_erp_notify+0x40/0xc0 [zfcp] [<00000985915e26f0>] call_timer_fn+0x38/0x190 [<00000985915e2944>] expire_timers+0xfc/0x190 [<00000985915e2ac4>] run_timer_softirq+0xec/0x218 [<0000098591ca7c4c>] __do_softirq+0x144/0x398 [<00000985915110aa>] do_softirq_own_stack+0x72/0x88 [<0000098591551b58>] irq_exit+0xb0/0xb8 [<0000098591510c6a>] do_IRQ+0x82/0xb0 [<0000098591ca7140>] ext_int_handler+0x128/0x12c [<0000098591722d98>] clear_subpage.constprop.13+0x38/0x60 ([<000009859172ae4c>] clear_huge_page+0xec/0x250) [<000009859177e7a2>] do_huge_pmd_anonymous_page+0x32a/0x768 [<000009859172a712>] __handle_mm_fault+0x88a/0x900 [<000009859172a860>] handle_mm_fault+0xd8/0x1b0 [<0000098591529ef6>] do_dat_exception+0x136/0x3e8 [<0000098591ca6d34>] pgm_check_handler+0x1c8/0x220 Last Breaking-Event-Address: [<001fffff80549c88>] zfcp_erp_timeout_handler+0x10/0x18 [zfcp] Kernel panic - not syncing: Fatal exception in interrupt Link: https://lore.kernel.org/r/20200623140242.98864-1-maier@linux.ibm.com Fixes: 75492a51568b ("s390/scsi: Convert timers to use timer_setup()") Cc: #4.15+ Reviewed-by: Julian Wiedmann Signed-off-by: Steffen Maier Signed-off-by: Martin K. Petersen Signed-off-by: Greg Kroah-Hartman

Merge tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi

2020-04-10T19:21:11Z

Pull more SCSI updates from James Bottomley: "This is a batch of changes that didn't make it in the initial pull request because the lpfc series had to be rebased to redo an incorrect split. It's basically driver updates to lpfc, target, bnx2fc and ufs with the rest being minor updates except the sr_block_release one which fixes a use after free introduced by the removal of the global mutex in the first patch set" * tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: (35 commits) scsi: core: Add DID_ALLOC_FAILURE and DID_MEDIUM_ERROR to hostbyte_table scsi: ufs: Use ufshcd_config_pwr_mode() when scaling gear scsi: bnx2fc: fix boolreturn.cocci warnings scsi: zfcp: use fallthrough; scsi: aacraid: do not overwrite retval in aac_reset_adapter() scsi: sr: Fix sr_block_release() scsi: aic7xxx: Remove more FreeBSD-specific code scsi: mpt3sas: Fix kernel panic observed on soft HBA unplug scsi: ufs: set device as active power mode after resetting device scsi: iscsi: Report unbind session event when the target has been removed scsi: lpfc: Change default SCSI LUN QD to 64 scsi: libfc: rport state move to PLOGI if all PRLI retry exhausted scsi: libfc: If PRLI rejected, move rport to PLOGI state scsi: bnx2fc: Update the driver version to 2.12.13 scsi: bnx2fc: Fix SCSI command completion after cleanup is posted scsi: bnx2fc: Process the RQE with CQE in interrupt context scsi: target: use the stack for XCOPY passthrough cmds scsi: target: increase XCOPY I/O size scsi: target: avoid per-loop XCOPY buffer allocations scsi: target: drop xcopy DISK BLOCK LENGTH debug ...

s390/qdio: remove cdev from init_data

2020-04-06T11:13:50Z

It's no longer needed. Signed-off-by: Julian Wiedmann Reviewed-by: Benjamin Block Signed-off-by: Vasily Gorbik

s390/qdio: allow for non-contiguous SBAL array in init_data

2020-04-06T11:13:50Z

Upper-layer drivers allocate their SBALs by calling qdio_alloc_buffers() for each individual queue. But when later passing the SBAL addresses to qdio_establish(), they need to be in a single array of pointers. So if the driver uses multiple Input or Output queues, it needs to allocate a temporary array just to present all its SBAL pointers in this layout. This patch slightly changes the format of the QDIO initialization data, so that drivers can pass a per-queue array where each element points to a queue's SBAL array. zfcp doesn't use multiple queues, so the impact there is trivial. For qeth this brings a nice reduction in complexity, and removes a page-sized allocation. Signed-off-by: Julian Wiedmann Reviewed-by: Benjamin Block Signed-off-by: Vasily Gorbik

zfcp: inline zfcp_qdio_setup_init_data()

2020-04-06T11:13:50Z

In preparation for a subsequent patch, move the setup of init_data into the only caller. Signed-off-by: Julian Wiedmann Reviewed-by: Benjamin Block Signed-off-by: Vasily Gorbik

s390/qdio: cleanly split alloc and establish

2020-04-06T11:13:50Z

All that qdio_allocate() actually uses from the init_data is the cdev, and the number of Input and Output Queues. Have the driver pass those as parameters, and defer the init_data processing into qdio_establish(). This includes writing per-device(!) trace entries, and most of the sanity checks. Signed-off-by: Julian Wiedmann Reviewed-by: Benjamin Block Signed-off-by: Vasily Gorbik

Merge tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi

2020-04-03T00:03:53Z

Pull SCSI updates from James Bottomley: "This series has a huge amount of churn because it pulls in Mauro's doc update changing all our txt files to rst ones. Excluding that, we have the usual driver updates (qla2xxx, ufs, lpfc, zfcp, ibmvfc, pm80xx, aacraid), a treewide update for scnprintf and some other minor updates. The major core change is Hannes moving functions out of the aacraid driver and into the core" * tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: (223 commits) scsi: aic7xxx: aic97xx: Remove FreeBSD-specific code scsi: ufs: Do not rely on prefetched data scsi: dc395x: remove dc395x_bios_param scsi: libiscsi: Fix error count for active session scsi: hpsa: correct race condition in offload enabled scsi: message: fusion: Replace zero-length array with flexible-array member scsi: qedi: Add PCI shutdown handler support scsi: qedi: Add MFW error recovery process scsi: ufs: Enable block layer runtime PM for well-known logical units scsi: ufs-qcom: Override devfreq parameters scsi: ufshcd: Let vendor override devfreq parameters scsi: ufshcd: Update the set frequency to devfreq scsi: ufs: Resume ufs host before accessing ufs device scsi: ufs-mediatek: customize the delay for enabling host scsi: ufs: make HCE polling more compact to improve initialization latency scsi: ufs: allow custom delay prior to host enabling scsi: ufs-mediatek: use common delay function scsi: ufs: introduce common and flexible delay function scsi: ufs: use an enum for host capabilities scsi: ufs: fix uninitialized tx_lanes in ufshcd_disable_tx_lcc() ...

scsi: zfcp: use fallthrough;

2020-04-01T02:24:02Z

Convert the various uses of fallthrough comments to fallthrough; Done via script Link: https://lore.kernel.org/lkml/b56602fcf79f849e733e7b521bb0e17895d390fa.1582230379.git.joe.com/ Signed-off-by: Joe Perches Reviewed-by: Fedor Loshakov Reviewed-by: Steffen Maier [bblock@linux.ibm.com: resolved merge conflict with recently upstream-sent patch "zfcp: expose fabric name as common fc_host sysfs attribute"] Link: https://lore.kernel.org/r/d14669a67a17392490d3184117941123765db1a4.1585663010.git.bblock@linux.ibm.com Signed-off-by: Benjamin Block Signed-off-by: Martin K. Petersen

scsi: zfcp: log FC Endpoint Security errors

2020-03-17T17:12:42Z

Log any FC Endpoint Security errors to the kernel ring buffer with rate- limiting. Link: https://lore.kernel.org/r/20200312174505.51294-11-maier@linux.ibm.com Reviewed-by: Steffen Maier Signed-off-by: Jens Remus Signed-off-by: Steffen Maier Signed-off-by: Martin K. Petersen