{"id":"CVE-2021-47261","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nIB/mlx5: Fix initializing CQ fragments buffer\n\nThe function init_cq_frag_buf() can be called to initialize the current CQ\nfragments buffer cq-\u003ebuf, or the temporary cq-\u003eresize_buf that is filled\nduring CQ resize operation.\n\nHowever, the offending commit started to use function get_cqe() for\ngetting the CQEs, the issue with this change is that get_cqe() always\nreturns CQEs from cq-\u003ebuf, which leads us to initialize the wrong buffer,\nand in case of enlarging the CQ we try to access elements beyond the size\nof the current cq-\u003ebuf and eventually hit a kernel panic.\n\n [exception RIP: init_cq_frag_buf+103]\n  [ffff9f799ddcbcd8] mlx5_ib_resize_cq at ffffffffc0835d60 [mlx5_ib]\n  [ffff9f799ddcbdb0] ib_resize_cq at ffffffffc05270df [ib_core]\n  [ffff9f799ddcbdc0] llt_rdma_setup_qp at ffffffffc0a6a712 [llt]\n  [ffff9f799ddcbe10] llt_rdma_cc_event_action at ffffffffc0a6b411 [llt]\n  [ffff9f799ddcbe98] llt_rdma_client_conn_thread at ffffffffc0a6bb75 [llt]\n  [ffff9f799ddcbec8] kthread at ffffffffa66c5da1\n  [ffff9f799ddcbf50] ret_from_fork_nospec_begin at ffffffffa6d95ddd\n\nFix it by getting the needed CQE by calling mlx5_frag_buf_get_wqe() that\ntakes the correct source buffer as a parameter.","modified":"2026-03-13T05:20:40.100773Z","published":"2024-05-21T15:15:14.770Z","related":["SUSE-SU-2024:1979-1","SUSE-SU-2024:1983-1","SUSE-SU-2024:2010-1","SUSE-SU-2024:2183-1","SUSE-SU-2024:2184-1","SUSE-SU-2024:2185-1","SUSE-SU-2025:0898-1","SUSE-SU-2025:0942-1","SUSE-SU-2025:0943-1"],"references":[{"type":"FIX","url":"https://git.kernel.org/stable/c/1ec2dcd680c71d0d36fa25638b327a468babd5c9"},{"type":"FIX","url":"https://git.kernel.org/stable/c/2ba0aa2feebda680ecfc3c552e867cf4d1b05a3a"},{"type":"FIX","url":"https://git.kernel.org/stable/c/3e670c54eda238cb8a1ea93538a79ae89285c1c4"},{"type":"FIX","url":"https://git.kernel.org/stable/c/91f7fdc4cc10542ca1045c06aad23365f0d067e0"},{"type":"FIX","url":"https://git.kernel.org/stable/c/e3ecd9c09fcc10cf6b2bc67e2990c397c40a8c26"}],"affected":[{"database_specific":{"source":"https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2021-47261.json","unresolved_ranges":[{"events":[{"introduced":"4.17"},{"fixed":"4.19.195"}]},{"events":[{"introduced":"4.20"},{"fixed":"5.4.126"}]},{"events":[{"introduced":"5.5"},{"fixed":"5.10.44"}]},{"events":[{"introduced":"5.11"},{"fixed":"5.12.11"}]},{"events":[{"introduced":"0"},{"last_affected":"5.13-rc1"}]},{"events":[{"introduced":"0"},{"last_affected":"5.13-rc2"}]},{"events":[{"introduced":"0"},{"last_affected":"5.13-rc3"}]},{"events":[{"introduced":"0"},{"last_affected":"5.13-rc4"}]},{"events":[{"introduced":"0"},{"last_affected":"5.13-rc5"}]}]}}],"schema_version":"1.7.5","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H"}]}