6.1-stable review patch. If anyone has any objections, please let me know.
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From: Zhu Yanjun yanjun.zhu@linux.dev
[ Upstream commit 86dfdd8288907f03c18b7fb462e0e232c4f98d89 ]
In the commit aee2424246f9 ("RDMA/iwcm: Fix a use-after-free related to destroying CM IDs"), the function flush_workqueue is invoked to flush the work queue iwcm_wq.
But at that time, the work queue iwcm_wq was created via the function alloc_ordered_workqueue without the flag WQ_MEM_RECLAIM.
Because the current process is trying to flush the whole iwcm_wq, if iwcm_wq doesn't have the flag WQ_MEM_RECLAIM, verify that the current process is not reclaiming memory or running on a workqueue which doesn't have the flag WQ_MEM_RECLAIM as that can break forward-progress guarantee leading to a deadlock.
The call trace is as below:
[ 125.350876][ T1430] Call Trace: [ 125.356281][ T1430] <TASK> [ 125.361285][ T1430] ? __warn (kernel/panic.c:693) [ 125.367640][ T1430] ? check_flush_dependency (kernel/workqueue.c:3706 (discriminator 9)) [ 125.375689][ T1430] ? report_bug (lib/bug.c:180 lib/bug.c:219) [ 125.382505][ T1430] ? handle_bug (arch/x86/kernel/traps.c:239) [ 125.388987][ T1430] ? exc_invalid_op (arch/x86/kernel/traps.c:260 (discriminator 1)) [ 125.395831][ T1430] ? asm_exc_invalid_op (arch/x86/include/asm/idtentry.h:621) [ 125.403125][ T1430] ? check_flush_dependency (kernel/workqueue.c:3706 (discriminator 9)) [ 125.410984][ T1430] ? check_flush_dependency (kernel/workqueue.c:3706 (discriminator 9)) [ 125.418764][ T1430] __flush_workqueue (kernel/workqueue.c:3970) [ 125.426021][ T1430] ? __pfx___might_resched (kernel/sched/core.c:10151) [ 125.433431][ T1430] ? destroy_cm_id (drivers/infiniband/core/iwcm.c:375) iw_cm [ 125.441209][ T1430] ? __pfx___flush_workqueue (kernel/workqueue.c:3910) [ 125.473900][ T1430] ? _raw_spin_lock_irqsave (arch/x86/include/asm/atomic.h:107 include/linux/atomic/atomic-arch-fallback.h:2170 include/linux/atomic/atomic-instrumented.h:1302 include/asm-generic/qspinlock.h:111 include/linux/spinlock.h:187 include/linux/spinlock_api_smp.h:111 kernel/locking/spinlock.c:162) [ 125.473909][ T1430] ? __pfx__raw_spin_lock_irqsave (kernel/locking/spinlock.c:161) [ 125.482537][ T1430] _destroy_id (drivers/infiniband/core/cma.c:2044) rdma_cm [ 125.495072][ T1430] nvme_rdma_free_queue (drivers/nvme/host/rdma.c:656 drivers/nvme/host/rdma.c:650) nvme_rdma [ 125.505827][ T1430] nvme_rdma_reset_ctrl_work (drivers/nvme/host/rdma.c:2180) nvme_rdma [ 125.505831][ T1430] process_one_work (kernel/workqueue.c:3231) [ 125.515122][ T1430] worker_thread (kernel/workqueue.c:3306 kernel/workqueue.c:3393) [ 125.515127][ T1430] ? __pfx_worker_thread (kernel/workqueue.c:3339) [ 125.531837][ T1430] kthread (kernel/kthread.c:389) [ 125.539864][ T1430] ? __pfx_kthread (kernel/kthread.c:342) [ 125.550628][ T1430] ret_from_fork (arch/x86/kernel/process.c:147) [ 125.558840][ T1430] ? __pfx_kthread (kernel/kthread.c:342) [ 125.558844][ T1430] ret_from_fork_asm (arch/x86/entry/entry_64.S:257) [ 125.566487][ T1430] </TASK> [ 125.566488][ T1430] ---[ end trace 0000000000000000 ]---
Fixes: aee2424246f9 ("RDMA/iwcm: Fix a use-after-free related to destroying CM IDs") Link: https://patch.msgid.link/r/20240820113336.19860-1-yanjun.zhu@linux.dev Reported-by: kernel test robot oliver.sang@intel.com Closes: https://lore.kernel.org/oe-lkp/202408151633.fc01893c-oliver.sang@intel.com Tested-by: kernel test robot oliver.sang@intel.com Signed-off-by: Zhu Yanjun yanjun.zhu@linux.dev Reviewed-by: Bart Van Assche bvanassche@acm.org Signed-off-by: Jason Gunthorpe jgg@nvidia.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/infiniband/core/iwcm.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/infiniband/core/iwcm.c b/drivers/infiniband/core/iwcm.c index 2d09d1be38f19..3e4941754b48d 100644 --- a/drivers/infiniband/core/iwcm.c +++ b/drivers/infiniband/core/iwcm.c @@ -1191,7 +1191,7 @@ static int __init iw_cm_init(void) if (ret) return ret;
- iwcm_wq = alloc_ordered_workqueue("iw_cm_wq", 0); + iwcm_wq = alloc_ordered_workqueue("iw_cm_wq", WQ_MEM_RECLAIM); if (!iwcm_wq) goto err_alloc;