Describe CVE-2021-47076.
What is CVE-2021-47076?
In the Linux kernel, the following vulnerability has been resolved:

RDMA/rxe: Return CQE error if invalid lkey was supplied

RXE is missing update of WQE status in LOCAL_WRITE failures.  This caused
the following kernel panic if someone sent an atomic operation with an
explicitly wrong lkey.

[leonro@vm ~]$ mkt test
test_atomic_invalid_lkey (tests.test_atomic.AtomicTest) ...
 WARNING: CPU: 5 PID: 263 at drivers/infiniband/sw/rxe/rxe_comp.c:740 rxe_completer+0x1a6d/0x2e30 [rdma_rxe]
 Modules linked in: crc32_generic rdma_rxe ip6_udp_tunnel udp_tunnel rdma_ucm rdma_cm ib_umad ib_ipoib iw_cm ib_cm mlx5_ib ib_uverbs ib_core mlx5_core ptp pps_core
 CPU: 5 PID: 263 Comm: python3 Not tainted 5.13.0-rc1+ #2936
 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014
 RIP: 0010:rxe_completer+0x1a6d/0x2e30 [rdma_rxe]
 Code: 03 0f 8e 65 0e 00 00 3b 93 10 06 00 00 0f 84 82 0a 00 00 4c 89 ff 4c 89 44 24 38 e8 2d 74 a9 e1 4c 8b 44 24 38 e9 1c f5 ff ff <0f> 0b e9 0c e8 ff ff b8 05 00 00 00 41 bf 05 00 00 00 e9 ab e7 ff
 RSP: 0018:ffff8880158af090 EFLAGS: 00010246
 RAX: 0000000000000000 RBX: ffff888016a78000 RCX: ffffffffa0cf1652
 RDX: 1ffff9200004b442 RSI: 0000000000000004 RDI: ffffc9000025a210
 RBP: dffffc0000000000 R08: 00000000ffffffea R09: ffff88801617740b
 R10: ffffed1002c2ee81 R11: 0000000000000007 R12: ffff88800f3b63e8
 R13: ffff888016a78008 R14: ffffc9000025a180 R15: 000000000000000c
 FS:  00007f88b622a740(0000) GS:ffff88806d540000(0000) knlGS:0000000000000000
 CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 CR2: 00007f88b5a1fa10 CR3: 000000000d848004 CR4: 0000000000370ea0
 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
 Call Trace:
  rxe_do_task+0x130/0x230 [rdma_rxe]
  rxe_rcv+0xb11/0x1df0 [rdma_rxe]
  rxe_loopback+0x157/0x1e0 [rdma_rxe]
  rxe_responder+0x5532/0x7620 [rdma_rxe]
  rxe_do_task+0x130/0x230 [rdma_rxe]
  rxe_rcv+0x9c8/0x1df0 [rdma_rxe]
  rxe_loopback+0x157/0x1e0 [rdma_rxe]
  rxe_requester+0x1efd/0x58c0 [rdma_rxe]
  rxe_do_task+0x130/0x230 [rdma_rxe]
  rxe_post_send+0x998/0x1860 [rdma_rxe]
  ib_uverbs_post_send+0xd5f/0x1220 [ib_uverbs]
  ib_uverbs_write+0x847/0xc80 [ib_uverbs]
  vfs_write+0x1c5/0x840
  ksys_write+0x176/0x1d0
  do_syscall_64+0x3f/0x80
  entry_SYSCALL_64_after_hwframe+0x44/0xae.