The io_uring subsystem in the Linux kernel allowed the MAX_RW_COUNT limit to be bypassed in the PROVIDE_BUFFERS operation, which led to negative values being usedin mem_rw when reading /proc/<PID>/mem. This could be used to create a heap overflow leading to arbitrary code execution in the kernel. It was addressed via commit d1f82808877b ("io_uring: truncate lengths larger than MAX_RW_COUNT on provide buffers") (v5.13-rc1) and backported to the stable kernels in v5.12.4, v5.11.21, and v5.10.37. It was introduced in ddf0322db79c ("io_uring: add IORING_OP_PROVIDE_BUFFERS") (v5.7-rc1).
The product does not correctly calculate the size to be used when allocating a buffer, which could lead to a buffer overflow.
The product writes data past the end, or before the beginning, of the intended buffer.
| Link | Tags |
|---|---|
| https://ubuntu.com/security/notices/USN-4950-1 | third party advisory vendor advisory |
| https://ubuntu.com/security/notices/USN-4949-1 | third party advisory vendor advisory |
| https://www.openwall.com/lists/oss-security/2021/05/11/13 | patch mailing list third party advisory |
| https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=d1f82808877bb10d3deee7cf3374a4eb3fb582db | patch vendor advisory |
| https://www.zerodayinitiative.com/advisories/ZDI-21-589/ | third party advisory vdb entry |
| https://security.netapp.com/advisory/ntap-20210716-0004/ | third party advisory |