Linux Kernel up to 5.12.6 RDMA lib/refcount.c rxe_qp_do_cleanup use after free

Summaryinfo

A vulnerability classified as problematic was found in Linux Kernel up to 5.12.6. This affects the function rxe_qp_do_cleanup in the library lib/refcount.c of the component RDMA. The manipulation results in use after free. This vulnerability is cataloged as CVE-2021-47078. There is no exploit available. Upgrading the affected component is advised.

Detailsinfo

A vulnerability was found in Linux Kernel up to 5.12.6 (Operating System). It has been classified as problematic. Affected is the function rxe_qp_do_cleanup in the library lib/refcount.c of the component RDMA. The manipulation with an unknown input leads to a use after free vulnerability. CWE is classifying the issue as CWE-416. Referencing memory after it has been freed can cause a program to crash, use unexpected values, or execute code. The impact remains unknown. CVE summarizes:

In the Linux kernel, the following vulnerability has been resolved: RDMA/rxe: Clear all QP fields if creation failed rxe_qp_do_cleanup() relies on valid pointer values in QP for the properly created ones, but in case rxe_qp_from_init() failed it was filled with garbage and caused tot the following error. refcount_t: underflow; use-after-free. WARNING: CPU: 1 PID: 12560 at lib/refcount.c:28 refcount_warn_saturate+0x1d1/0x1e0 lib/refcount.c:28 Modules linked in: CPU: 1 PID: 12560 Comm: syz-executor.4 Not tainted 5.12.0-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:refcount_warn_saturate+0x1d1/0x1e0 lib/refcount.c:28 Code: e9 db fe ff ff 48 89 df e8 2c c2 ea fd e9 8a fe ff ff e8 72 6a a7 fd 48 c7 c7 e0 b2 c1 89 c6 05 dc 3a e6 09 01 e8 ee 74 fb 04 0b e9 af fe ff ff 0f 1f 84 00 00 00 00 00 41 56 41 55 41 54 55 RSP: 0018:ffffc900097ceba8 EFLAGS: 00010286 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000 RDX: 0000000000040000 RSI: ffffffff815bb075 RDI: fffff520012f9d67 RBP: 0000000000000003 R08: 0000000000000000 R09: 0000000000000000 R10: ffffffff815b4eae R11: 0000000000000000 R12: ffff8880322a4800 R13: ffff8880322a4940 R14: ffff888033044e00 R15: 0000000000000000 FS: 00007f6eb2be3700(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fdbe5d41000 CR3: 000000001d181000 CR4: 00000000001506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __refcount_sub_and_test include/linux/refcount.h:283 [inline] __refcount_dec_and_test include/linux/refcount.h:315 [inline] refcount_dec_and_test include/linux/refcount.h:333 [inline] kref_put include/linux/kref.h:64 [inline] rxe_qp_do_cleanup+0x96f/0xaf0 drivers/infiniband/sw/rxe/rxe_qp.c:805 execute_in_process_context+0x37/0x150 kernel/workqueue.c:3327 rxe_elem_release+0x9f/0x180 drivers/infiniband/sw/rxe/rxe_pool.c:391 kref_put include/linux/kref.h:65 [inline] rxe_create_qp+0x2cd/0x310 drivers/infiniband/sw/rxe/rxe_verbs.c:425 _ib_create_qp drivers/infiniband/core/core_priv.h:331 [inline] ib_create_named_qp+0x2ad/0x1370 drivers/infiniband/core/verbs.c:1231 ib_create_qp include/rdma/ib_verbs.h:3644 [inline] create_mad_qp+0x177/0x2d0 drivers/infiniband/core/mad.c:2920 ib_mad_port_open drivers/infiniband/core/mad.c:3001 [inline] ib_mad_init_device+0xd6f/0x1400 drivers/infiniband/core/mad.c:3092 add_client_context+0x405/0x5e0 drivers/infiniband/core/device.c:717 enable_device_and_get+0x1cd/0x3b0 drivers/infiniband/core/device.c:1331 ib_register_device drivers/infiniband/core/device.c:1413 [inline] ib_register_device+0x7c7/0xa50 drivers/infiniband/core/device.c:1365 rxe_register_device+0x3d5/0x4a0 drivers/infiniband/sw/rxe/rxe_verbs.c:1147 rxe_add+0x12fe/0x16d0 drivers/infiniband/sw/rxe/rxe.c:247 rxe_net_add+0x8c/0xe0 drivers/infiniband/sw/rxe/rxe_net.c:503 rxe_newlink drivers/infiniband/sw/rxe/rxe.c:269 [inline] rxe_newlink+0xb7/0xe0 drivers/infiniband/sw/rxe/rxe.c:250 nldev_newlink+0x30e/0x550 drivers/infiniband/core/nldev.c:1555 rdma_nl_rcv_msg+0x36d/0x690 drivers/infiniband/core/netlink.c:195 rdma_nl_rcv_skb drivers/infiniband/core/netlink.c:239 [inline] rdma_nl_rcv+0x2ee/0x430 drivers/infiniband/core/netlink.c:259 netlink_unicast_kernel net/netlink/af_netlink.c:1312 [inline] netlink_unicast+0x533/0x7d0 net/netlink/af_netlink.c:1338 netlink_sendmsg+0x856/0xd90 net/netlink/af_netlink.c:1927 sock_sendmsg_nosec net/socket.c:654 [inline] sock_sendmsg+0xcf/0x120 net/socket.c:674 ____sys_sendmsg+0x6e8/0x810 net/socket.c:2350 ___sys_sendmsg+0xf3/0x170 net/socket.c:2404 __sys_sendmsg+0xe5/0x1b0 net/socket.c:2433 do_syscall_64+0x3a/0xb0 arch/x86/entry/common.c:47 entry_SYSCALL_64_after_hwframe+0 ---truncated---

The weakness was shared 03/02/2024. The advisory is shared for download at git.kernel.org. This vulnerability is traded as CVE-2021-47078 since 02/29/2024. There are known technical details, but no exploit is available.

Upgrading to version 4.9.270, 4.14.234, 4.19.192, 5.4.122, 5.10.40, 5.12.7 or 5.13 eliminates this vulnerability. Applying the patch c65391dd9f0a/6a8086a42dfb/f3783c415bf6/a62225d951d7/2ee4d79c3649/03344e843ab6/67f29896fdc8 is able to eliminate this problem. The bugfix is ready for download at git.kernel.org. The best possible mitigation is suggested to be upgrading to the latest version.

Once again VulDB remains the best source for vulnerability data.

Productinfo

Type

• Operating System

Vendor

• Linux

Name

• Kernel

Version

• 4.9.269
• 4.14.233
• 4.19.191
• 5.4.121
• 5.10.0
• 5.10.1
• 5.10.2
• 5.10.3
• 5.10.4
• 5.10.5
• 5.10.6
• 5.10.7
• 5.10.8
• 5.10.9
• 5.10.10
• 5.10.11
• 5.10.12
• 5.10.13
• 5.10.14
• 5.10.15
• 5.10.16
• 5.10.17
• 5.10.18
• 5.10.19
• 5.10.20
• 5.10.21
• 5.10.22
• 5.10.23
• 5.10.24
• 5.10.25
• 5.10.26
• 5.10.27
• 5.10.28
• 5.10.29
• 5.10.30
• 5.10.31
• 5.10.32
• 5.10.33
• 5.10.34
• 5.10.35
• 5.10.36
• 5.10.37
• 5.10.38
• 5.10.39
• 5.12.0
• 5.12.1
• 5.12.2
• 5.12.3
• 5.12.4
• 5.12.5
• 5.12.6

License

• open-source

Website

• Vendor: https://www.kernel.org/

CPE 2.3info

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CPE 2.2info

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CVSSv4info

CVSSv3info

CVSSv2info

Exploitinginfo

Threat Intelligenceinfo

Countermeasuresinfo

Timelineinfo

Sourcesinfo

Entryinfo

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