Linux Kernel up to 5.12.12 include/linux/slab.h netlbl_cipsov4_add_std memory leak

Summaryinfo

A vulnerability was found in Linux Kernel up to 5.12.12. It has been declared as critical. The impacted element is the function netlbl_cipsov4_add_std in the library include/linux/slab.h. Such manipulation leads to memory leak. This vulnerability is uniquely identified as CVE-2021-47250. No exploit exists. It is recommended to upgrade the affected component.

Detailsinfo

A vulnerability was found in Linux Kernel up to 5.12.12 and classified as critical. Affected by this issue is the function netlbl_cipsov4_add_std in the library include/linux/slab.h. The manipulation with an unknown input leads to a memory leak vulnerability. Using CWE to declare the problem leads to CWE-401. The product does not sufficiently track and release allocated memory after it has been used, which slowly consumes remaining memory. Impacted is availability. CVE summarizes:

In the Linux kernel, the following vulnerability has been resolved: net: ipv4: fix memory leak in netlbl_cipsov4_add_std Reported by syzkaller: BUG: memory leak unreferenced object 0xffff888105df7000 (size 64): comm "syz-executor842", pid 360, jiffies 4294824824 (age 22.546s) hex dump (first 32 bytes): 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ backtrace: [] kmalloc include/linux/slab.h:590 [inline] [] kzalloc include/linux/slab.h:720 [inline] [] netlbl_cipsov4_add_std net/netlabel/netlabel_cipso_v4.c:145 [inline] [] netlbl_cipsov4_add+0x390/0x2340 net/netlabel/netlabel_cipso_v4.c:416 [] genl_family_rcv_msg_doit.isra.0+0x20e/0x320 net/netlink/genetlink.c:739 [] genl_family_rcv_msg net/netlink/genetlink.c:783 [inline] [] genl_rcv_msg+0x2bf/0x4f0 net/netlink/genetlink.c:800 [] netlink_rcv_skb+0x134/0x3d0 net/netlink/af_netlink.c:2504 [] genl_rcv+0x24/0x40 net/netlink/genetlink.c:811 [] netlink_unicast_kernel net/netlink/af_netlink.c:1314 [inline] [] netlink_unicast+0x4a0/0x6a0 net/netlink/af_netlink.c:1340 [] netlink_sendmsg+0x789/0xc70 net/netlink/af_netlink.c:1929 [] sock_sendmsg_nosec net/socket.c:654 [inline] [] sock_sendmsg+0x139/0x170 net/socket.c:674 [] ____sys_sendmsg+0x658/0x7d0 net/socket.c:2350 [] ___sys_sendmsg+0xf8/0x170 net/socket.c:2404 [] __sys_sendmsg+0xd3/0x190 net/socket.c:2433 [] do_syscall_64+0x37/0x90 arch/x86/entry/common.c:47 [] entry_SYSCALL_64_after_hwframe+0x44/0xae The memory of doi_def->map.std pointing is allocated in netlbl_cipsov4_add_std, but no place has freed it. It should be freed in cipso_v4_doi_free which frees the cipso DOI resource.

The advisory is shared for download at git.kernel.org. This vulnerability is handled as CVE-2021-47250 since 04/10/2024. The exploitation is known to be difficult. There are known technical details, but no exploit is available.

Upgrading to version 4.4.274, 4.9.274, 4.14.238, 4.19.196, 5.4.128, 5.10.46 or 5.12.13 eliminates this vulnerability. Applying the patch 212166510582/086e92b1d68c/6dcea66d3bb5/5340858147e3/398a24447eb6/deeeb65c6ee4/0ffb460be3ab/d612c3f3fae2 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.

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Productinfo

Type

• Operating System

Vendor

• Linux

Name

• Kernel

Version

• 4.4.273
• 4.9.273
• 4.14.237
• 4.19.195
• 5.4.127
• 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
• 5.10.40
• 5.10.41
• 5.10.42
• 5.10.43
• 5.10.44
• 5.10.45
• 5.12.0
• 5.12.1
• 5.12.2
• 5.12.3
• 5.12.4
• 5.12.5
• 5.12.6
• 5.12.7
• 5.12.8
• 5.12.9
• 5.12.10
• 5.12.11
• 5.12.12

License

• open-source

Website

• Vendor: https://www.kernel.org/

CPE 2.3info

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Entryinfo

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