CVE-2025-22010

In the Linux kernel, the following vulnerability has been resolved:

RDMA/hns: Fix soft lockup during bt pages loop

Driver runs a for-loop when allocating bt pages and mapping them with buffer pages. When a large buffer (e.g. MR over 100GB) is being allocated, it may require a considerable loop count. This will lead to soft lockup:

    watchdog: BUG: soft lockup - CPU#27 stuck for 22s!
    ...
    Call trace:
     hem_list_alloc_mid_bt+0x124/0x394 [hns_roce_hw_v2]
     hns_roce_hem_list_request+0xf8/0x160 [hns_roce_hw_v2]
     hns_roce_mtr_create+0x2e4/0x360 [hns_roce_hw_v2]
     alloc_mr_pbl+0xd4/0x17c [hns_roce_hw_v2]
     hns_roce_reg_user_mr+0xf8/0x190 [hns_roce_hw_v2]
     ib_uverbs_reg_mr+0x118/0x290

    watchdog: BUG: soft lockup - CPU#35 stuck for 23s!
    ...
    Call trace:
     hns_roce_hem_list_find_mtt+0x7c/0xb0 [hns_roce_hw_v2]
     mtr_map_bufs+0xc4/0x204 [hns_roce_hw_v2]
     hns_roce_mtr_create+0x31c/0x3c4 [hns_roce_hw_v2]
     alloc_mr_pbl+0xb0/0x160 [hns_roce_hw_v2]
     hns_roce_reg_user_mr+0x108/0x1c0 [hns_roce_hw_v2]
     ib_uverbs_reg_mr+0x120/0x2bc

Add a cond_resched() to fix soft lockup during these loops. In order not to affect the allocation performance of normal-size buffer, set the loop count of a 100GB MR as the threshold to call cond_resched().

Weakness

The product does not properly acquire or release a lock on a resource, leading to unexpected resource state changes and behaviors.

Affected Software

Extended Description

Locking is a type of synchronization behavior that ensures that multiple independently-operating processes or threads do not interfere with each other when accessing the same resource. All processes/threads are expected to follow the same steps for locking. If these steps are not followed precisely - or if no locking is done at all - then another process/thread could modify the shared resource in a way that is not visible or predictable to the original process. This can lead to data or memory corruption, denial of service, etc.

Potential Mitigations

Related Attack Patterns

• https://cwe.mitre.org/data/definitions/25.html
• https://cwe.mitre.org/data/definitions/26.html
• https://cwe.mitre.org/data/definitions/27.html

References

• https://git.kernel.org/stable/c/13a52f6c9ff99f7d88f81da535cb4e85eade662b
• https://git.kernel.org/stable/c/25655580136de59ec89f09089dd28008ea440fc9
• https://git.kernel.org/stable/c/4104b0023ff66b5df900d23dbf38310893deca79
• https://git.kernel.org/stable/c/461eb4ddede266df8f181f578732bb01742c3fd6
• https://git.kernel.org/stable/c/975355faba56c0751292ed15a90c3e2c7dc0aad6
• https://git.kernel.org/stable/c/9ab20fec7a1ce3057ad86afd27bfd08420b7cd11
• https://git.kernel.org/stable/c/efe544462fc0b499725364f90bd0f8bbf16f861a