Linux Kernel up to 5.10.39/5.12.6 RDMA user_entry_size divide by zero

Summaryinfo

A vulnerability, which was classified as critical, has been found in Linux Kernel up to 5.10.39/5.12.6. This vulnerability affects the function user_entry_size of the component RDMA. This manipulation causes divide by zero. This vulnerability is registered as CVE-2021-47080. No exploit is available. It is advisable to upgrade the affected component.

Detailsinfo

A vulnerability was found in Linux Kernel up to 5.10.39/5.12.6 (Operating System). It has been declared as critical. Affected by this vulnerability is the function user_entry_size of the component RDMA. The manipulation with an unknown input leads to a divide by zero vulnerability. The CWE definition for the vulnerability is CWE-369. The product divides a value by zero. As an impact it is known to affect availability. The summary by CVE is:

In the Linux kernel, the following vulnerability has been resolved: RDMA/core: Prevent divide-by-zero error triggered by the user The user_entry_size is supplied by the user and later used as a denominator to calculate number of entries. The zero supplied by the user will trigger the following divide-by-zero error: divide error: 0000 [#1] SMP KASAN PTI CPU: 4 PID: 497 Comm: c_repro Not tainted 5.13.0-rc1+ #281 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014 RIP: 0010:ib_uverbs_handler_UVERBS_METHOD_QUERY_GID_TABLE+0x1b1/0x510 Code: 87 59 03 00 00 e8 9f ab 1e ff 48 8d bd a8 00 00 00 e8 d3 70 41 ff 44 0f b7 b5 a8 00 00 00 e8 86 ab 1e ff 31 d2 4c 89 f0 31 ff f7 f5 48 89 d6 48 89 54 24 10 48 89 04 24 e8 1b ad 1e ff 48 8b RSP: 0018:ffff88810416f828 EFLAGS: 00010246 RAX: 0000000000000008 RBX: 1ffff1102082df09 RCX: ffffffff82183f3d RDX: 0000000000000000 RSI: ffff888105f2da00 RDI: 0000000000000000 RBP: ffff88810416fa98 R08: 0000000000000001 R09: ffffed102082df5f R10: ffff88810416faf7 R11: ffffed102082df5e R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000008 R15: ffff88810416faf0 FS: 00007f5715efa740(0000) GS:ffff88811a700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000020000840 CR3: 000000010c2e0001 CR4: 0000000000370ea0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: ? ib_uverbs_handler_UVERBS_METHOD_INFO_HANDLES+0x4b0/0x4b0 ib_uverbs_cmd_verbs+0x1546/0x1940 ib_uverbs_ioctl+0x186/0x240 __x64_sys_ioctl+0x38a/0x1220 do_syscall_64+0x3f/0x80 entry_SYSCALL_64_after_hwframe+0x44/0xae

The weakness was published 03/02/2024. The advisory is shared at git.kernel.org. This vulnerability is known as CVE-2021-47080 since 02/29/2024. Technical details are known, but no exploit is available.

The vulnerability scanner Nessus provides a plugin with the ID 239841 (TencentOS Server 4: kernel (TSSA-2024:0960)), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 5.10.40, 5.12.7 or 5.13 eliminates this vulnerability. Applying the patch 66ab7fcdac34/e6871b4270c0/54d87913f147 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.

The vulnerability is also documented in the vulnerability database at Tenable (239841). If you want to get the best quality for vulnerability data then you always have to consider VulDB.

Productinfo

Type

• Operating System

Vendor

• Linux

Name

• Kernel

Version

• 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

• 🔍
• 🔍
• 🔍

CPE 2.2info

• 🔍
• 🔍
• 🔍

CVSSv4info

CVSSv3info

CVSSv2info

Exploitinginfo

Threat Intelligenceinfo

Countermeasuresinfo

Timelineinfo

Sourcesinfo

Entryinfo

If you want to get the best quality for vulnerability data then you always have to consider VulDB.

Discussion