Divya Indi f427f4d621 IB/sa: Resolv use-after-free in ib_nl_make_request() ... There is a race condition where ib_nl_make_request() inserts the request data into the linked list but the timer in ib_nl_request_timeout() can see it and destroy it before ib_nl_send_msg() is done touching it. This could happen, for instance, if there is a long delay allocating memory during nlmsg_new() This causes a use-after-free in the send_mad() thread: [<ffffffffa02f43cb>] ? ib_pack+0x17b/0x240 [ib_core] [ <ffffffffa032aef1>] ib_sa_path_rec_get+0x181/0x200 [ib_sa] [<ffffffffa0379db0>] rdma_resolve_route+0x3c0/0x8d0 [rdma_cm] [<ffffffffa0374450>] ? cma_bind_port+0xa0/0xa0 [rdma_cm] [<ffffffffa040f850>] ? rds_rdma_cm_event_handler_cmn+0x850/0x850 [rds_rdma] [<ffffffffa040f22c>] rds_rdma_cm_event_handler_cmn+0x22c/0x850 [rds_rdma] [<ffffffffa040f860>] rds_rdma_cm_event_handler+0x10/0x20 [rds_rdma] [<ffffffffa037778e>] addr_handler+0x9e/0x140 [rdma_cm] [<ffffffffa026cdb4>] process_req+0x134/0x190 [ib_addr] [<ffffffff810a02f9>] process_one_work+0x169/0x4a0 [<ffffffff810a0b2b>] worker_thread+0x5b/0x560 [<ffffffff810a0ad0>] ? flush_delayed_work+0x50/0x50 [<ffffffff810a68fb>] kthread+0xcb/0xf0 [<ffffffff816ec49a>] ? __schedule+0x24a/0x810 [<ffffffff816ec49a>] ? __schedule+0x24a/0x810 [<ffffffff810a6830>] ? kthread_create_on_node+0x180/0x180 [<ffffffff816f25a7>] ret_from_fork+0x47/0x90 [<ffffffff810a6830>] ? kthread_create_on_node+0x180/0x180 The ownership rule is once the request is on the list, ownership transfers to the list and the local thread can't touch it any more, just like for the normal MAD case in send_mad(). Thus, instead of adding before send and then trying to delete after on errors, move the entire thing under the spinlock so that the send and update of the lists are atomic to the conurrent threads. Lightly reoganize things so spinlock safe memory allocations are done in the final NL send path and the rest of the setup work is done before and outside the lock. Fixes: 3ebd2fd0d0 ("IB/sa: Put netlink request into the request list before sending") Link: https://lore.kernel.org/r/1592964789-14533-1-git-send-email-divya.indi@oracle.com Signed-off-by: Divya Indi <divya.indi@oracle.com> Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>		2020-07-02 16:05:12 -03:00
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core	IB/sa: Resolv use-after-free in ib_nl_make_request()	2020-07-02 16:05:12 -03:00
hw	IB/hfi1: Do not destroy link_wq when the device is shut down	2020-07-02 13:54:50 -03:00
sw	RDMA/rvt: Fix potential memory leak caused by rvt_alloc_rq	2020-06-18 09:35:47 -03:00
ulp	treewide: replace '---help---' in Kconfig files with 'help'	2020-06-14 01:57:21 +09:00
Kconfig	treewide: replace '---help---' in Kconfig files with 'help'	2020-06-14 01:57:21 +09:00
Makefile	treewide: Add SPDX license identifier - Makefile/Kconfig	2019-05-21 10:50:46 +02:00