kernel.git/drivers/infiniband/core/cm.c, branch linux-5.7.y

RDMA/cm: Protect access to remote_sidr_table

2020-07-29T08:19:42Z

[ Upstream commit 87c4c774cbef5c68b3df96827c2fb07f1aa80152 ] cm.lock must be held while accessing remote_sidr_table. This fixes the below NULL pointer dereference. BUG: kernel NULL pointer dereference, address: 0000000000000000 #PF: supervisor write access in kernel mode #PF: error_code(0x0002) - not-present page PGD 0 P4D 0 Oops: 0002 [#1] SMP PTI CPU: 2 PID: 7288 Comm: udaddy Not tainted 5.7.0_for_upstream_perf_2020_06_09_15_14_20_38 #1 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.12.1-0-ga5cab58e9a3f-prebuilt.qemu.org 04/01/2014 RIP: 0010:rb_erase+0x10d/0x360 Code: 00 00 00 48 89 c1 48 89 d0 48 8b 50 08 48 39 ca 74 48 f6 02 01 75 af 48 8b 7a 10 48 89 c1 48 83 c9 01 48 89 78 08 48 89 42 10 <48> 89 0f 48 8b 08 48 89 0a 48 83 e1 fc 48 89 10 0f 84 b1 00 00 00 RSP: 0018:ffffc90000f77c30 EFLAGS: 00010086 RAX: ffff8883df27d458 RBX: ffff8883df27da58 RCX: ffff8883df27d459 RDX: ffff8883d183fa58 RSI: ffffffffa01e8d00 RDI: 0000000000000000 RBP: ffff8883d62ac800 R08: 0000000000000000 R09: 00000000000000ce R10: 000000000000000a R11: 0000000000000000 R12: ffff8883df27da00 R13: ffffc90000f77c98 R14: 0000000000000130 R15: 0000000000000000 FS: 00007f009f877740(0000) GS:ffff8883f1a00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000000 CR3: 00000003d467e003 CR4: 0000000000160ee0 Call Trace: cm_send_sidr_rep_locked+0x15a/0x1a0 [ib_cm] ib_send_cm_sidr_rep+0x2b/0x50 [ib_cm] cma_send_sidr_rep+0x8b/0xe0 [rdma_cm] __rdma_accept+0x21d/0x2b0 [rdma_cm] ? ucma_get_ctx+0x2b/0xe0 [rdma_ucm] ? _copy_from_user+0x30/0x60 ucma_accept+0x13e/0x1e0 [rdma_ucm] ucma_write+0xb4/0x130 [rdma_ucm] vfs_write+0xad/0x1a0 ksys_write+0x9d/0xb0 do_syscall_64+0x48/0x130 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x7f009ef60924 Code: 00 f7 d8 64 89 02 48 c7 c0 ff ff ff ff eb b7 0f 1f 80 00 00 00 00 8b 05 2a ef 2c 00 48 63 ff 85 c0 75 13 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 54 f3 c3 66 90 55 53 48 89 d5 48 89 f3 48 83 RSP: 002b:00007fff843edf38 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 000055743042e1d0 RCX: 00007f009ef60924 RDX: 0000000000000130 RSI: 00007fff843edf40 RDI: 0000000000000003 RBP: 00007fff843ee0e0 R08: 0000000000000000 R09: 0000557430433090 R10: 0000000000000001 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fff843edf40 R14: 000000000000038c R15: 00000000ffffff00 CR2: 0000000000000000 Fixes: 6a8824a74bc9 ("RDMA/cm: Allow ib_send_cm_sidr_rep() to be done under lock") Link: https://lore.kernel.org/r/20200716105519.1424266-1-leon@kernel.org Signed-off-by: Maor Gottlieb Signed-off-by: Leon Romanovsky Signed-off-by: Jason Gunthorpe Signed-off-by: Sasha Levin

RDMA/cm: Spurious WARNING triggered in cm_destroy_id()

2020-06-24T15:49:03Z

[ Upstream commit fba97dc7fc76b2c9a909fa0b3786d30a9899f5cf ] If the cm_id state is IB_CM_REP_SENT when cm_destroy_id() is called, it calls cm_send_rej_locked(). In cm_send_rej_locked(), it calls cm_enter_timewait() and the state is changed to IB_CM_TIMEWAIT. Now back to cm_destroy_id(), it breaks from the switch statement, and the next call is WARN_ON(cm_id->state != IB_CM_IDLE). This triggers a spurious warning. Instead, the code should goto retest after returning from cm_send_rej_locked() to move the state to IDLE. Fixes: 67b3c8dceac6 ("RDMA/cm: Make sure the cm_id is in the IB_CM_IDLE state in destroy") Link: https://lore.kernel.org/r/1591191218-9446-1-git-send-email-ka-cheong.poon@oracle.com Signed-off-by: Ka-Cheong Poon Signed-off-by: Jason Gunthorpe Signed-off-by: Sasha Levin

RDMA/cm: Fix an error check in cm_alloc_id_priv()

2020-04-14T19:01:38Z

The xa_alloc_cyclic_irq() function returns either 0 or 1 on success and negatives on error. This code treats 1 as an error and returns ERR_PTR(1) which will cause an Oops in the caller. Fixes: ae78ff3a0f0c ("RDMA/cm: Convert local_id_table to XArray") Link: https://lore.kernel.org/r/20200407093714.GA80285@mwanda Signed-off-by: Dan Carpenter Reviewed-by: Matthew Wilcox (Oracle) Signed-off-by: Jason Gunthorpe

RDMA/cm: Fix missing RDMA_CM_EVENT_REJECTED event after receiving REJ message

2020-04-14T18:50:49Z

The cm_reset_to_idle() call before formatting event changed the CM_ID state from IB_CM_REQ_RCVD to be IB_CM_IDLE. It caused to wrong value of CM_REJ_MESSAGE_REJECTED field. The result of that was that rdma_reject() calls in the passive side didn't generate RDMA_CM_EVENT_REJECTED event in the active side. Fixes: 81ddb41f876d ("RDMA/cm: Allow ib_send_cm_rej() to be done under lock") Link: https://lore.kernel.org/r/20200406173242.1465911-1-leon@kernel.org Signed-off-by: Leon Romanovsky Signed-off-by: Jason Gunthorpe

RDMA/cm: Make sure the cm_id is in the IB_CM_IDLE state in destroy

2020-03-17T20:05:54Z

The first switch statement in cm_destroy_id() tries to move the ID to either IB_CM_IDLE or IB_CM_TIMEWAIT. Both states will block concurrent MAD handlers from progressing. Previous patches removed the unreliably lock/unlock sequences in this flow, this patch removes the extra locking steps and adds the missing parts to guarantee that destroy reaches IB_CM_IDLE. There is no point in leaving the ID in the IB_CM_TIMEWAIT state the memory about to be kfreed. Rework things to hold the lock across all the state transitions and directly assert when done that it ended up in IB_CM_IDLE as expected. This was accompanied by a careful audit of all the state transitions here, which generally did end up in IDLE on their success and non-racy paths. Link: https://lore.kernel.org/r/20200310092545.251365-16-leon@kernel.org Signed-off-by: Leon Romanovsky Signed-off-by: Jason Gunthorpe

RDMA/cm: Allow ib_send_cm_sidr_rep() to be done under lock

2020-03-17T20:05:54Z

The first thing ib_send_cm_sidr_rep() does is obtain the lock, so use the usual unlocked wrapper, locked actor pattern here. Get rid of the cm_reject_sidr_req() wrapper so each call site can call the locked or unlocked version as required. This avoids a sketchy lock/unlock sequence (which could allow state to change) during cm_destroy_id(). Link: https://lore.kernel.org/r/20200310092545.251365-15-leon@kernel.org Signed-off-by: Leon Romanovsky Signed-off-by: Jason Gunthorpe

RDMA/cm: Allow ib_send_cm_rej() to be done under lock

2020-03-17T20:05:54Z

The first thing ib_send_cm_rej() does is obtain the lock, so use the usual unlocked wrapper, locked actor pattern here. This avoids a sketchy lock/unlock sequence (which could allow state to change) during cm_destroy_id(). While here simplify some of the logic in the implementation. Link: https://lore.kernel.org/r/20200310092545.251365-14-leon@kernel.org Signed-off-by: Leon Romanovsky Signed-off-by: Jason Gunthorpe

RDMA/cm: Allow ib_send_cm_drep() to be done under lock

2020-03-17T20:05:53Z

The first thing ib_send_cm_drep() does is obtain the lock, so use the usual unlocked wrapper, locked actor pattern here. This avoids a sketchy lock/unlock sequence (which could allow state to change) during cm_destroy_id(). Link: https://lore.kernel.org/r/20200310092545.251365-13-leon@kernel.org Signed-off-by: Leon Romanovsky Signed-off-by: Jason Gunthorpe

RDMA/cm: Allow ib_send_cm_dreq() to be done under lock

2020-03-17T20:05:53Z

The first thing ib_send_cm_dreq() does is obtain the lock, so use the usual unlocked wrapper, locked actor pattern here. This avoids a sketchy lock/unlock sequence (which could allow state to change) during cm_destroy_id(). Link: https://lore.kernel.org/r/20200310092545.251365-12-leon@kernel.org Signed-off-by: Leon Romanovsky Signed-off-by: Jason Gunthorpe

RDMA/cm: Add some lockdep assertions for cm_id_priv->lock

2020-03-17T20:05:53Z

These functions all touch state, so must be called under the lock. Inspection shows this is currently true. Link: https://lore.kernel.org/r/20200310092545.251365-11-leon@kernel.org Signed-off-by: Leon Romanovsky Signed-off-by: Jason Gunthorpe