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From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To: linux-kernel@vger.kernel.org
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
	stable@vger.kernel.org,
	Sebastian Andrzej Siewior <bigeasy@linutronix.de>,
	Logan Gunthorpe <logang@deltatee.com>,
	Thomas Gleixner <tglx@linutronix.de>,
	"Peter Zijlstra (Intel)" <peterz@infradead.org>,
	Bjorn Helgaas <bhelgaas@google.com>,
	Sasha Levin <sashal@kernel.org>
Subject: [PATCH 4.14 016/199] PCI/switchtec: Fix init_completion race condition with poll_wait()
Date: Wed, 22 Apr 2020 11:55:42 +0200	[thread overview]
Message-ID: <20200422095059.842802344@linuxfoundation.org> (raw)
In-Reply-To: <20200422095057.806111593@linuxfoundation.org>

From: Logan Gunthorpe <logang@deltatee.com>

[ Upstream commit efbdc769601f4d50018bf7ca50fc9f7c67392ece ]

The call to init_completion() in mrpc_queue_cmd() can theoretically
race with the call to poll_wait() in switchtec_dev_poll().

  poll()			write()
    switchtec_dev_poll()   	  switchtec_dev_write()
      poll_wait(&s->comp.wait);      mrpc_queue_cmd()
			               init_completion(&s->comp)
				         init_waitqueue_head(&s->comp.wait)

To my knowledge, no one has hit this bug.

Fix this by using reinit_completion() instead of init_completion() in
mrpc_queue_cmd().

Fixes: 080b47def5e5 ("MicroSemi Switchtec management interface driver")

Reported-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Link: https://lkml.kernel.org/r/20200313183608.2646-1-logang@deltatee.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/pci/switch/switchtec.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/pci/switch/switchtec.c b/drivers/pci/switch/switchtec.c
index bf229b442e723..6ef0d4b756f09 100644
--- a/drivers/pci/switch/switchtec.c
+++ b/drivers/pci/switch/switchtec.c
@@ -412,7 +412,7 @@ static int mrpc_queue_cmd(struct switchtec_user *stuser)
 	kref_get(&stuser->kref);
 	stuser->read_len = sizeof(stuser->data);
 	stuser_set_state(stuser, MRPC_QUEUED);
-	init_completion(&stuser->comp);
+	reinit_completion(&stuser->comp);
 	list_add_tail(&stuser->list, &stdev->mrpc_queue);
 
 	mrpc_cmd_submit(stdev);
-- 
2.20.1




  parent reply	other threads:[~2020-04-22 10:10 UTC|newest]

Thread overview: 132+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-04-22  9:55 [PATCH 4.14 000/199] 4.14.177-rc1 review Greg Kroah-Hartman
2020-04-22  9:55 ` [PATCH 4.14 001/199] bus: sunxi-rsb: Return correct data when mixing 16-bit and 8-bit reads Greg Kroah-Hartman
2020-04-22  9:55 ` [PATCH 4.14 002/199] net: vxge: fix wrong __VA_ARGS__ usage Greg Kroah-Hartman
2020-04-22  9:55 ` [PATCH 4.14 003/199] hinic: fix a bug of waitting for IO stopped Greg Kroah-Hartman
2020-04-22  9:55 ` [PATCH 4.14 004/199] hinic: fix wrong para of wait_for_completion_timeout Greg Kroah-Hartman
2020-04-22  9:55 ` [PATCH 4.14 005/199] cxgb4/ptp: pass the sign of offset delta in FW CMD Greg Kroah-Hartman
2020-04-22  9:55 ` [PATCH 4.14 006/199] qlcnic: Fix bad kzalloc null test Greg Kroah-Hartman
2020-04-22  9:55 ` [PATCH 4.14 007/199] i2c: st: fix missing struct parameter description Greg Kroah-Hartman
2020-04-22  9:55 ` [PATCH 4.14 008/199] null_blk: Fix the null_add_dev() error path Greg Kroah-Hartman
2020-04-22  9:55 ` [PATCH 4.14 009/199] null_blk: Handle null_add_dev() failures properly Greg Kroah-Hartman
2020-04-22  9:55 ` [PATCH 4.14 010/199] null_blk: fix spurious IO errors after failed past-wp access Greg Kroah-Hartman
2020-04-22  9:55 ` [PATCH 4.14 011/199] x86: Dont let pgprot_modify() change the page encryption bit Greg Kroah-Hartman
2020-04-22  9:55 ` [PATCH 4.14 012/199] block: keep bdi->io_pages in sync with max_sectors_kb for stacked devices Greg Kroah-Hartman
2020-04-22  9:55 ` [PATCH 4.14 013/199] irqchip/versatile-fpga: Handle chained IRQs properly Greg Kroah-Hartman
2020-04-22  9:55 ` [PATCH 4.14 014/199] sched: Avoid scale real weight down to zero Greg Kroah-Hartman
2020-04-22  9:55 ` [PATCH 4.14 015/199] selftests/x86/ptrace_syscall_32: Fix no-vDSO segfault Greg Kroah-Hartman
2020-04-22  9:55 ` Greg Kroah-Hartman [this message]
2020-04-22  9:55 ` [PATCH 4.14 017/199] libata: Remove extra scsi_host_put() in ata_scsi_add_hosts() Greg Kroah-Hartman
2020-04-22  9:55 ` [PATCH 4.14 018/199] gfs2: Dont demote a glock until its revokes are written Greg Kroah-Hartman
2020-04-22  9:55 ` [PATCH 4.14 019/199] x86/boot: Use unsigned comparison for addresses Greg Kroah-Hartman
2020-04-22  9:55 ` [PATCH 4.14 020/199] efi/x86: Ignore the memory attributes table on i386 Greg Kroah-Hartman
2020-04-22  9:55 ` [PATCH 4.14 021/199] genirq/irqdomain: Check pointer in irq_domain_alloc_irqs_hierarchy() Greg Kroah-Hartman
2020-04-22  9:55 ` [PATCH 4.14 022/199] block: Fix use-after-free issue accessing struct io_cq Greg Kroah-Hartman
2020-04-22  9:55 ` [PATCH 4.14 023/199] usb: dwc3: core: add support for disabling SS instances in park mode Greg Kroah-Hartman
2020-04-22  9:55 ` [PATCH 4.14 024/199] irqchip/gic-v4: Provide irq_retrigger to avoid circular locking dependency Greg Kroah-Hartman
2020-04-22  9:55 ` [PATCH 4.14 025/199] locking/lockdep: Avoid recursion in lockdep_count_{for,back}ward_deps() Greg Kroah-Hartman
2020-04-22  9:55 ` [PATCH 4.14 026/199] block, bfq: fix use-after-free in bfq_idle_slice_timer_body Greg Kroah-Hartman
2020-04-22  9:55 ` [PATCH 4.14 027/199] btrfs: remove a BUG_ON() from merge_reloc_roots() Greg Kroah-Hartman
2020-04-22  9:55 ` [PATCH 4.14 028/199] btrfs: track reloc roots based on their commit root bytenr Greg Kroah-Hartman
2020-04-22  9:55 ` [PATCH 4.14 029/199] uapi: rename ext2_swab() to swab() and share globally in swab.h Greg Kroah-Hartman
2020-04-22  9:55 ` [PATCH 4.14 030/199] misc: rtsx: set correct pcr_ops for rts522A Greg Kroah-Hartman
2020-04-22  9:55 ` [PATCH 4.14 031/199] slub: improve bit diffusion for freelist ptr obfuscation Greg Kroah-Hartman
2020-04-22  9:55 ` [PATCH 4.14 032/199] ASoC: fix regwmask Greg Kroah-Hartman
2020-04-22  9:55 ` [PATCH 4.14 033/199] ASoC: dapm: connect virtual mux with default value Greg Kroah-Hartman
2020-04-22  9:56 ` [PATCH 4.14 034/199] ASoC: dpcm: allow start or stop during pause for backend Greg Kroah-Hartman
2020-04-22  9:56 ` [PATCH 4.14 035/199] ASoC: topology: use name_prefix for new kcontrol Greg Kroah-Hartman
2020-04-22  9:56 ` [PATCH 4.14 036/199] usb: gadget: f_fs: Fix use after free issue as part of queue failure Greg Kroah-Hartman
2020-04-22  9:56 ` [PATCH 4.14 037/199] usb: gadget: composite: Inform controller driver of self-powered Greg Kroah-Hartman
2020-04-22  9:56 ` [PATCH 4.14 038/199] ALSA: usb-audio: Add mixer workaround for TRX40 and co Greg Kroah-Hartman
2020-04-22  9:56 ` [PATCH 4.14 039/199] ALSA: hda: Add driver blacklist Greg Kroah-Hartman
2020-04-22  9:56 ` [PATCH 4.14 040/199] ALSA: hda: Fix potential access overflow in beep helper Greg Kroah-Hartman
2020-04-22  9:56 ` [PATCH 4.14 041/199] ALSA: ice1724: Fix invalid access for enumerated ctl items Greg Kroah-Hartman
2020-04-22  9:56 ` [PATCH 4.14 042/199] ALSA: pcm: oss: Fix regression by buffer overflow fix Greg Kroah-Hartman
2020-04-22  9:56 ` [PATCH 4.14 043/199] ALSA: doc: Document PC Beep Hidden Register on Realtek ALC256 Greg Kroah-Hartman
2020-04-22  9:56 ` [PATCH 4.14 044/199] ALSA: hda/realtek - Set principled PC Beep configuration for ALC256 Greg Kroah-Hartman
2020-04-22  9:56 ` [PATCH 4.14 045/199] media: ti-vpe: cal: fix disable_irqs to only the intended target Greg Kroah-Hartman
2020-04-22  9:56 ` [PATCH 4.14 046/199] acpi/x86: ignore unspecified bit positions in the ACPI global lock field Greg Kroah-Hartman
2020-04-22  9:56 ` [PATCH 4.14 047/199] thermal: devfreq_cooling: inline all stubs for CONFIG_DEVFREQ_THERMAL=n Greg Kroah-Hartman
2020-04-22  9:56 ` [PATCH 4.14 048/199] nvme-fc: Revert "add module to ops template to allow module references" Greg Kroah-Hartman
2020-04-22  9:56 ` [PATCH 4.14 049/199] PCI/ASPM: Clear the correct bits when enabling L1 substates Greg Kroah-Hartman
2020-04-22  9:56 ` [PATCH 4.14 050/199] PCI: endpoint: Fix for concurrent memory allocation in OB address region Greg Kroah-Hartman
2020-04-22  9:56 ` [PATCH 4.14 051/199] KEYS: reaching the keys quotas correctly Greg Kroah-Hartman
2020-04-22  9:56 ` [PATCH 4.14 052/199] irqchip/versatile-fpga: Apply clear-mask earlier Greg Kroah-Hartman
2020-04-22  9:56 ` [PATCH 4.14 053/199] MIPS: OCTEON: irq: Fix potential NULL pointer dereference Greg Kroah-Hartman
2020-04-22  9:56 ` [PATCH 4.14 054/199] ath9k: Handle txpower changes even when TPC is disabled Greg Kroah-Hartman
2020-04-22  9:56 ` [PATCH 4.14 055/199] signal: Extend exec_id to 64bits Greg Kroah-Hartman
2020-04-22  9:56 ` [PATCH 4.14 056/199] x86/entry/32: Add missing ASM_CLAC to general_protection entry Greg Kroah-Hartman
2020-04-22  9:56 ` [PATCH 4.14 057/199] KVM: nVMX: Properly handle userspace interrupt window request Greg Kroah-Hartman
2020-04-22  9:56 ` [PATCH 4.14 058/199] KVM: s390: vsie: Fix region 1 ASCE sanity shadow address checks Greg Kroah-Hartman
2020-04-22  9:56 ` [PATCH 4.14 059/199] KVM: s390: vsie: Fix delivery of addressing exceptions Greg Kroah-Hartman
2020-04-22  9:56 ` [PATCH 4.14 060/199] KVM: x86: Allocate new rmap and large page tracking when moving memslot Greg Kroah-Hartman
2020-04-22  9:56 ` [PATCH 4.14 061/199] KVM: VMX: Always VMCLEAR in-use VMCSes during crash with kexec support Greg Kroah-Hartman
2020-04-22  9:56 ` [PATCH 4.14 062/199] KVM: VMX: fix crash cleanup when KVM wasnt used Greg Kroah-Hartman
2020-04-22  9:56 ` [PATCH 4.14 063/199] CIFS: Fix bug which the return value by asynchronous read is error Greg Kroah-Hartman
2020-04-22  9:56 ` [PATCH 4.14 064/199] btrfs: drop block from cache on error in relocation Greg Kroah-Hartman
2020-04-22  9:56 ` [PATCH 4.14 065/199] crypto: mxs-dcp - fix scatterlist linearization for hash Greg Kroah-Hartman
2020-04-22  9:56 ` [PATCH 4.14 066/199] ALSA: hda: Initialize power_state field properly Greg Kroah-Hartman
2020-04-22  9:56 ` [PATCH 4.14 067/199] net: rtnl_configure_link: fix dev flags changes arg to __dev_notify_flags Greg Kroah-Hartman
2020-04-22  9:56 ` [PATCH 4.14 068/199] powerpc/pseries: Drop pointless static qualifier in vpa_debugfs_init() Greg Kroah-Hartman
2020-04-22  9:56 ` [PATCH 4.14 069/199] x86/speculation: Remove redundant arch_smt_update() invocation Greg Kroah-Hartman
2020-04-22  9:56 ` [PATCH 4.14 070/199] tools: gpio: Fix out-of-tree build regression Greg Kroah-Hartman
2020-04-22  9:56 ` [PATCH 4.14 071/199] mm: Use fixed constant in page_frag_alloc instead of size + 1 Greg Kroah-Hartman
2020-04-22  9:56 ` [PATCH 4.14 072/199] dm verity fec: fix memory leak in verity_fec_dtr Greg Kroah-Hartman
2020-04-22  9:56 ` [PATCH 4.14 073/199] scsi: zfcp: fix missing erp_lock in port recovery trigger for point-to-point Greg Kroah-Hartman
2020-04-22  9:56 ` [PATCH 4.14 074/199] arm64: armv8_deprecated: Fix undef_hook mask for thumb setend Greg Kroah-Hartman
2020-04-22  9:56 ` [PATCH 4.14 075/199] rtc: omap: Use define directive for PIN_CONFIG_ACTIVE_HIGH Greg Kroah-Hartman
2020-04-22  9:56 ` [PATCH 4.14 076/199] NFS: Fix a page leak in nfs_destroy_unlinked_subrequests() Greg Kroah-Hartman
2020-04-22  9:56 ` [PATCH 4.14 077/199] ext4: fix a data race at inode->i_blocks Greg Kroah-Hartman
2020-04-22  9:56 ` [PATCH 4.14 078/199] fs/filesystems.c: downgrade user-reachable WARN_ONCE() to pr_warn_once() Greg Kroah-Hartman
2020-04-22  9:56 ` [PATCH 4.14 079/199] ocfs2: no need try to truncate file beyond i_size Greg Kroah-Hartman
2020-04-22  9:56 ` [PATCH 4.14 080/199] perf tools: Support Python 3.8+ in Makefile Greg Kroah-Hartman
2020-04-22  9:56 ` [PATCH 4.14 081/199] s390/diag: fix display of diagnose call statistics Greg Kroah-Hartman
2020-04-22  9:56 ` [PATCH 4.14 082/199] Input: i8042 - add Acer Aspire 5738z to nomux list Greg Kroah-Hartman
2020-04-22  9:56 ` [PATCH 4.14 083/199] kmod: make request_module() return an error when autoloading is disabled Greg Kroah-Hartman
2020-04-22  9:56 ` [PATCH 4.14 084/199] cpufreq: powernv: Fix use-after-free Greg Kroah-Hartman
2020-04-22  9:56 ` [PATCH 4.14 085/199] hfsplus: fix crash and filesystem corruption when deleting files Greg Kroah-Hartman
2020-04-22  9:56 ` [PATCH 4.14 086/199] libata: Return correct status in sata_pmp_eh_recover_pm() when ATA_DFLAG_DETACH is set Greg Kroah-Hartman
2020-04-22  9:56 ` [PATCH 4.14 087/199] powerpc/powernv/idle: Restore AMR/UAMOR/AMOR after idle Greg Kroah-Hartman
2020-04-22  9:56 ` [PATCH 4.14 088/199] powerpc/64/tm: Dont let userspace set regs->trap via sigreturn Greg Kroah-Hartman
2020-04-22  9:56 ` [PATCH 4.14 089/199] powerpc/hash64/devmap: Use H_PAGE_THP_HUGE when setting up huge devmap PTE entries Greg Kroah-Hartman
2020-04-22  9:56 ` [PATCH 4.14 090/199] powerpc/xive: Use XIVE_BAD_IRQ instead of zero to catch non configured IPIs Greg Kroah-Hartman
2020-04-22  9:56 ` [PATCH 4.14 091/199] powerpc/kprobes: Ignore traps that happened in real mode Greg Kroah-Hartman
2020-04-22  9:56 ` [PATCH 4.14 092/199] scsi: mpt3sas: Fix kernel panic observed on soft HBA unplug Greg Kroah-Hartman
2020-04-22  9:56 ` [PATCH 4.14 093/199] powerpc: Add attributes for setjmp/longjmp Greg Kroah-Hartman
2020-04-22  9:57 ` [PATCH 4.14 094/199] powerpc: Make setjmp/longjmp signature standard Greg Kroah-Hartman
2020-04-22  9:57 ` [PATCH 4.14 095/199] Btrfs: fix crash during unmount due to race with delayed inode workers Greg Kroah-Hartman
2020-04-22  9:57 ` [PATCH 4.14 096/199] btrfs: use nofs allocations for running delayed items Greg Kroah-Hartman
2020-04-22  9:57 ` [PATCH 4.14 097/199] dm zoned: remove duplicate nr_rnd_zones increase in dmz_init_zone() Greg Kroah-Hartman
2020-04-22  9:57 ` [PATCH 4.14 098/199] crypto: caam - update xts sector size for large input length Greg Kroah-Hartman
2020-04-22  9:57 ` [PATCH 4.14 099/199] drm/dp_mst: Fix clearing payload state on topology disable Greg Kroah-Hartman
2020-04-22  9:57 ` [PATCH 4.14 100/199] drm: Remove PageReserved manipulation from drm_pci_alloc Greg Kroah-Hartman
2020-04-22  9:57 ` [PATCH 4.14 101/199] ftrace/kprobe: Show the maxactive number on kprobe_events Greg Kroah-Hartman
2020-04-22  9:57 ` [PATCH 4.14 102/199] ipmi: fix hung processes in __get_guid() Greg Kroah-Hartman
2020-04-22  9:57 ` [PATCH 4.14 103/199] powerpc/fsl_booke: Avoid creating duplicate tlb1 entry Greg Kroah-Hartman
2020-04-22  9:57 ` [PATCH 4.14 104/199] misc: echo: Remove unnecessary parentheses and simplify check for zero Greg Kroah-Hartman
2020-04-22  9:57 ` [PATCH 4.14 105/199] mfd: dln2: Fix sanity checking for endpoints Greg Kroah-Hartman
2020-04-22  9:57 ` [PATCH 4.14 106/199] amd-xgbe: Use __napi_schedule() in BH context Greg Kroah-Hartman
2020-04-22  9:57 ` [PATCH 4.14 107/199] hsr: check protocol version in hsr_newlink() Greg Kroah-Hartman
2020-04-22  9:57 ` [PATCH 4.14 108/199] net: ipv4: devinet: Fix crash when add/del multicast IP with autojoin Greg Kroah-Hartman
2020-04-22  9:57 ` [PATCH 4.14 109/199] net: ipv6: do not consider routes via gateways for anycast address check Greg Kroah-Hartman
2020-04-22  9:57 ` [PATCH 4.14 110/199] net: qrtr: send msgs from local of same id as broadcast Greg Kroah-Hartman
2020-04-22  9:57 ` [PATCH 4.14 111/199] net: revert default NAPI poll timeout to 2 jiffies Greg Kroah-Hartman
2020-04-22  9:57 ` [PATCH 4.14 112/199] net: stmmac: dwmac-sunxi: Provide TX and RX fifo sizes Greg Kroah-Hartman
2020-04-22  9:57 ` [PATCH 4.14 113/199] scsi: ufs: Fix ufshcd_hold() caused scheduling while atomic Greg Kroah-Hartman
2020-04-22  9:57 ` [PATCH 4.14 114/199] jbd2: improve comments about freeing data buffers whose page mapping is NULL Greg Kroah-Hartman
2020-04-22  9:57 ` [PATCH 4.14 115/199] pwm: pca9685: Fix PWM/GPIO inter-operation Greg Kroah-Hartman
2020-04-22  9:57 ` [PATCH 4.14 116/199] ext4: fix incorrect group count in ext4_fill_super error message Greg Kroah-Hartman
2020-04-22  9:57 ` [PATCH 4.14 117/199] ext4: fix incorrect inodes per group in " Greg Kroah-Hartman
2020-04-22  9:57 ` [PATCH 4.14 118/199] ASoC: Intel: mrfld: fix incorrect check on p->sink Greg Kroah-Hartman
2020-04-22  9:57 ` [PATCH 4.14 119/199] ASoC: Intel: mrfld: return error codes when an error occurs Greg Kroah-Hartman
2020-04-22  9:57 ` [PATCH 4.14 120/199] ALSA: usb-audio: Dont override ignore_ctl_error value from the map Greg Kroah-Hartman
2020-04-22  9:57 ` [PATCH 4.14 121/199] tracing: Fix the race between registering snapshot event trigger and triggering snapshot operation Greg Kroah-Hartman
2020-04-22  9:57 ` [PATCH 4.14 122/199] btrfs: check commit root generation in should_ignore_root Greg Kroah-Hartman
2020-04-22  9:57 ` [PATCH 4.14 123/199] mac80211_hwsim: Use kstrndup() in place of kasprintf() Greg Kroah-Hartman
2020-04-22  9:57 ` [PATCH 4.14 124/199] ext4: do not zeroout extents beyond i_disksize Greg Kroah-Hartman
2020-04-22  9:57 ` [PATCH 4.14 125/199] dm flakey: check for null arg_name in parse_features() Greg Kroah-Hartman
2020-04-22  9:57 ` [PATCH 4.14 126/199] kvm: x86: Host feature SSBD doesnt imply guest feature SPEC_CTRL_SSBD Greg Kroah-Hartman
2020-04-22  9:57 ` [PATCH 4.14 127/199] scsi: target: remove boilerplate code Greg Kroah-Hartman
2020-04-22  9:57 ` [PATCH 4.14 128/199] scsi: target: fix hang when multiple threads try to destroy the same iscsi session Greg Kroah-Hartman
2020-04-22  9:57 ` [PATCH 4.14 129/199] x86/microcode/AMD: Increase microcode PATCH_MAX_SIZE Greg Kroah-Hartman
2020-04-23 10:20 ` [PATCH 4.14 000/199] 4.14.177-rc1 review Jon Hunter
2020-04-23 11:28 ` Naresh Kamboju

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