CVE-2021-46957

/// Technical description

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

riscv/kprobe: fix kernel panic when invoking sys_read traced by kprobe

The execution of sys_read end up hitting a BUG_ON() in __find_get_block

after installing kprobe at sys_read, the BUG message like the following:

[ 65.708663] ------------[ cut here ]------------

[ 65.709987] kernel BUG at fs/buffer.c:1251!

[ 65.711283] Kernel BUG [#1]

[ 65.712032] Modules linked in:

[ 65.712925] CPU: 0 PID: 51 Comm: sh Not tainted 5.12.0-rc4 #1

[ 65.714407] Hardware name: riscv-virtio,qemu (DT)

[ 65.715696] epc : __find_get_block+0x218/0x2c8

[ 65.716835] ra : __getblk_gfp+0x1c/0x4a

[ 65.717831] epc : ffffffe00019f11e ra : ffffffe00019f56a sp : ffffffe002437930

[ 65.719553] gp : ffffffe000f06030 tp : ffffffe0015abc00 t0 : ffffffe00191e038

[ 65.721290] t1 : ffffffe00191e038 t2 : 000000000000000a s0 : ffffffe002437960

[ 65.723051] s1 : ffffffe00160ad00 a0 : ffffffe00160ad00 a1 : 000000000000012a

[ 65.72

/// Remediation

Check the references section for vendor advisories, patches, and mitigation guidance. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.

/// References