In the Linux kernel, the following vulnerability has been resolved:
accel/rocket: fix NULL dereference and integer overflow in rocket_job_push()
rocket_job_push() allocates a temporary array to hold all input and
output GEM object pointers:
bos = kvmalloc_array(job->in_bo_count + job->out_bo_count,
sizeof(void *), GFP_KERNEL);
memcpy(bos, job->in_bos, job->in_bo_count * sizeof(void *));
memcpy(&bos[job->in_bo_count], job->out_bos, ...);
Two bugs exist:
- Missing NULL check: if kvmalloc_array() fails, bos is NULL and
the subsequent memcpy() dereferences it, causing a kernel NULL
pointer dereference.
- Integer overflow: in_bo_count and out_bo_count are both u32, set
directly from userspace-supplied in_bo_handle_count and
out_bo_handle_count with no prior validation. Their sum is computed
in u32 arithmetic and can wrap to a smaller value, causing the
allocation count passed to kvmalloc_array() to be smaller than
intended. Subsequent uses still operate on the original counts when
copying and locking objects, which may lead to out-of-bounds accesses
on the temporary array.
Fix by using check_add_overflow() to detect count overflow before the
allocation, and adding a NULL check on the allocation result.
BOD 26-04 (CISA's remediation timeline, Table 1)14 days if the affected system is publicly exposed; Fix on system upgrade if it is not.
In CISA KEV no (CISA's KEV catalog) · Automatable no (CISA's BOD 26-04 default) · Technical impact total (CISA's BOD 26-04 default). Where an input reads “CISA's BOD 26-04 default”, no one has published it for this CVE, and CISA's implementation guidance says: “If “Automatable” and “Technical Impact” information items about a CVE ID are not available and the CVE ID is not in the KEV Catalog, CISA will treat its values as “no” and “total,” respectively, until CISA or a third party provides metadata about the CVE ID. CISA will always provide the Vulnrichment data for a CVE ID listed in the KEV Catalog.” Whether your system is publicly exposed is yours to answer. BOD 26-04 binds US Federal Civilian Executive Branch agencies; for anyone else it is CISA's published timeline, a reference rather than an obligation. The directive · how EchelonGraph applies it