cbcvebase.
CVE-2021-47261
published 2024-05-21

CVE-2021-47261: In the Linux kernel, the following vulnerability has been resolved: IB/mlx5: Fix initializing CQ fragments buffer The function init_cq_frag_buf() can be called…

PriorityP339high7.8CVSS 3.1
AVLACLPRLUINSUCHIHAH
EPSS
0.23%
14.4th percentile
In the Linux kernel, the following vulnerability has been resolved: IB/mlx5: Fix initializing CQ fragments buffer The function init_cq_frag_buf() can be called to initialize the current CQ fragments buffer cq->buf, or the temporary cq->resize_buf that is filled during CQ resize operation. However, the offending commit started to use function get_cqe() for getting the CQEs, the issue with this change is that get_cqe() always returns CQEs from cq->buf, which leads us to initialize the wrong buffer, and in case of enlarging the CQ we try to access elements beyond the size of the current cq->buf and eventually hit a kernel panic. [exception RIP: init_cq_frag_buf+103] [ffff9f799ddcbcd8] mlx5_ib_resize_cq at ffffffffc0835d60 [mlx5_ib] [ffff9f799ddcbdb0] ib_resize_cq at ffffffffc05270df [ib_core] [ffff9f799ddcbdc0] llt_rdma_setup_qp at ffffffffc0a6a712 [llt] [ffff9f799ddcbe10] llt_rdma_cc_event_action at ffffffffc0a6b411 [llt] [ffff9f799ddcbe98] llt_rdma_client_conn_thread at ffffffffc0a6bb75 [llt] [ffff9f799ddcbec8] kthread at ffffffffa66c5da1 [ffff9f799ddcbf50] ret_from_fork_nospec_begin at ffffffffa6d95ddd Fix it by getting the needed CQE by calling mlx5_frag_buf_get_wqe() that takes the correct source buffer as a parameter.

Affected

16 ranges
VendorProductVersion rangeFixed in
debianlinux< linux 5.10.46-1 (bookworm)linux 5.10.46-1 (bookworm)
linuxlinux
linuxlinux>= 388ca8be00370db132464e27f745b8a0add19fcb < 1ec2dcd680c71d0d36fa25638b327a468babd5c91ec2dcd680c71d0d36fa25638b327a468babd5c9
linuxlinux>= 388ca8be00370db132464e27f745b8a0add19fcb < e3ecd9c09fcc10cf6b2bc67e2990c397c40a8c26e3ecd9c09fcc10cf6b2bc67e2990c397c40a8c26
linuxlinux>= 388ca8be00370db132464e27f745b8a0add19fcb < 91f7fdc4cc10542ca1045c06aad23365f0d067e091f7fdc4cc10542ca1045c06aad23365f0d067e0
linuxlinux>= 388ca8be00370db132464e27f745b8a0add19fcb < 3e670c54eda238cb8a1ea93538a79ae89285c1c43e670c54eda238cb8a1ea93538a79ae89285c1c4
linuxlinux>= 388ca8be00370db132464e27f745b8a0add19fcb < 2ba0aa2feebda680ecfc3c552e867cf4d1b05a3a2ba0aa2feebda680ecfc3c552e867cf4d1b05a3a
linuxlinux_kernel
linuxlinux_kernel>= 0 < 5.10.46-15.10.46-1
linuxlinux_kernel>= 0 < 5.10.46-15.10.46-1
linuxlinux_kernel>= 0 < 5.10.46-15.10.46-1
linuxlinux_kernel>= 0 < 5.10.46-15.10.46-1
linuxlinux_kernel>= 4.17 < 4.19.1954.19.195
linuxlinux_kernel>= 4.20 < 5.4.1265.4.126
linuxlinux_kernel>= 5.11 < 5.12.115.12.11
linuxlinux_kernel>= 5.5 < 5.10.445.10.44

CVSS provenance

nvdv3.17.8HIGHCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
osv7.8HIGH
vendor_debian7.8HIGH
vendor_redhat7.8HIGH
Stop checking back — get the weekly exploitation signal.

Every Monday: what got weaponized or added to CISA KEV in the last seven days — each CVE cross-linked to its PoC, Nuclei template, and detection rule. Free, one email a week, unsubscribe in one click.