CVE-2022-50543 RDMA/rxe: Fix mr->map double free
A double free vulnerability in the Linux kernel's RDMA/rxe driver allows local attackers to cause a system crash via memory corruption.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2022-50543?
CVE-2022-50543 is a high-severity use after free vulnerability in Linux kernel, published on 7 Oct 2025. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
In the Linux kernel, the following vulnerability has been resolved:
RDMA/rxe: Fix mr->map double free
rxe_mr_cleanup() which tries to free mr->map again will be called when rxe_mr_init_user() fails:
CPU: 0 PID: 4917 Comm: rdma_flush_serv Kdump: loaded Not tainted 6.1.0-rc1-roce-flush+ #25 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.0-0-gd239552ce722-prebuilt.qemu.org 04/01/2014 Call Trace: <TASK> dump_stack_lvl+0x45/0x5d panic+0x19e/0x349 end_report.part.0+0x54/0x7c kasan_report.cold+0xa/0xf rxe_mr_cleanup+0x9d/0xf0 [rdma_rxe] __rxe_cleanup+0x10a/0x1e0 [rdma_rxe] rxe_reg_user_mr+0xb7/0xd0 [rdma_rxe] ib_uverbs_reg_mr+0x26a/0x480 [ib_uverbs] ib_uverbs_handler_UVERBS_METHOD_INVOKE_WRITE+0x1a2/0x250 [ib_uverbs] ib_uverbs_cmd_verbs+0x1397/0x15a0 [ib_uverbs]
This issue was firstly exposed since commit b18c7da63fcb ("RDMA/rxe: Fix memory leak in error path code") and then we fixed it in commit 8ff5f5d9d8cf ("RDMA/rxe: Prevent double freeing rxe_map_set()") but this fix was reverted together at last by commit 1e75550648da (Revert "RDMA/rxe: Create duplicate mapping tables for FMRs")
Simply let rxe_mr_cleanup() always handle freeing the mr->map once it is successfully allocated.
Weakness: CWE-415
Which versions are affected by CVE-2022-50543?
It affects 1 product.
Products include Linux kernel.
How do I fix CVE-2022-50543?
Apply the vendor's patch.
Upgrade to the fixed version. These bugs are found with fuzzing and sanitisers and avoided by memory-safe languages. More about Use after free.
Is CVE-2022-50543 being exploited?
There is no known exploitation of CVE-2022-50543 in the wild and no public exploit code.
Other vulnerabilities in Linux kernel
Sources
Also known as DEBIAN-CVE-2022-50543, GHSA-rjw2-5698-2f3h, UBUNTU-CVE-2022-50543.