Reference page — cumulative record through Wednesday, August 19, 2026 UTC. Reference pages update as the archive grows; only dated daily editions are immutable pages of record.
Linux Linux — net/mlx5e: Avoid field-overflowing memcpy()
AV AC PR UI S C I A CVSS EPSS %ile KEV
L L L N U H H H 7.8 .0061 46.4 —
AFFECTED
Product Versions Fixed
Linux b5503b994ed5ed8dbfe821317e7b5b38acb065c5 – —
Linux 4.9 – 5.10.248
TIMELINE
Jun 20 Reserved by Linux
Jun 20 Published (CNA: Linux)
Aug 4 RESCORED — CVE-2022-48744 (Linux). CVSS 7.5 → 7.8 (NVD).
Description
In the Linux kernel, the following vulnerability has been resolved:
net/mlx5e: Avoid field-overflowing memcpy()
In preparation for FORTIFY_SOURCE performing compile-time and run-time
field bounds checking for memcpy(), memmove(), and memset(), avoid
intentionally writing across neighboring fields.
Use flexible arrays instead of zero-element arrays (which look like they
are always overflowing) and split the cross-field memcpy() into two halves
that can be appropriately bounds-checked by the compiler.
We were doing:
#define ETH_HLEN 14
#define VLAN_HLEN 4
...
#define MLX5E_XDP_MIN_INLINE (ETH_HLEN + VLAN_HLEN)
...
struct mlx5e_tx_wqe *wqe = mlx5_wq_cyc_get_wqe(wq, pi);
...
struct mlx5_wqe_eth_seg *eseg = &wqe->eth;
struct mlx5_wqe_data_seg *dseg = wqe->data;
...
memcpy(eseg->inline_hdr.start, xdptxd->data, MLX5E_XDP_MIN_INLINE);
target is wqe->eth.inline_hdr.start (which the compiler sees as being
2 bytes in size), but copying 18, intending to write across start
(really vlan_tci, 2 bytes). The remaining 16 bytes get written into
wqe->data[0], covering byte_count (4 bytes), lkey (4 bytes), and addr
(8 bytes).
struct mlx5e_tx_wqe {
struct mlx5_wqe_ctrl_seg ctrl; /* 0 16 */
struct mlx5_wqe_eth_seg eth; /* 16 16 */
struct mlx5_wqe_data_seg data[]; /* 32 0 */
/* size: 32, cachelines: 1, members: 3 */
/* last cacheline: 32 bytes */
};
struct mlx5_wqe_eth_seg {
u8 swp_outer_l4_offset; /* 0 1 */
u8 swp_outer_l3_offset; /* 1 1 */
u8 swp_inner_l4_offset; /* 2 1 */
u8 swp_inner_l3_offset; /* 3 1 */
u8 cs_flags; /* 4 1 */
u8 swp_flags; /* 5 1 */
__be16 mss; /* 6 2 */
__be32 flow_table_metadata; /* 8 4 */
union {
struct {
__be16 sz; /* 12 2 */
u8 start[2]; /* 14 2 */
} inline_hdr; /* 12 4 */
struct {
__be16 type; /* 12 2 */
__be16 vlan_tci; /* 14 2 */
} insert; /* 12 4 */
__be32 trailer; /* 12 4 */
}; /* 12 4 */
/* size: 16, cachelines: 1, members: 9 */
/* last cacheline: 16 bytes */
};
struct mlx5_wqe_data_seg {
__be32 byte_count; /* 0 4 */
__be32 lkey; /* 4 4 */
__be64 addr; /* 8 8 */
/* size: 16, cachelines: 1, members: 3 */
/* last cacheline: 16 bytes */
};
So, split the memcpy() so the compiler can reason about the buffer
sizes.
"pahole" shows no size nor member offset changes to struct mlx5e_tx_wqe
nor struct mlx5e_umr_wqe. "objdump -d" shows no meaningful object
code changes (i.e. only source line number induced differences and
optimizations).
Lifecycle
Complete event history — 3 events, chronological
| Date | Event | Detail |
| June 20, 2024 | Reserved | Reserved by Linux |
| June 20, 2024 | Published | Published (CNA: Linux) |
| August 4, 2026 | RESCORED | RESCORED — CVE-2022-48744 (Linux). CVSS 7.5 → 7.8 (NVD). |
Affected
Affected products and packages — 2 rows
| Vendor | Product / Package | Ecosystem | Version introduced | Fixed |
| Linux | Linux | — | b5503b994ed5ed8dbfe821317e7b5b38acb065c5 | — |
| Linux | Linux | — | 4.9 | 5.10.248 |
About this page
This is a reference page, not a dated page of record. It assembles the complete lifecycle of CVE-2022-48744 from the CVE Program record, NVD enrichment, the CISA KEV catalog, EPSS, and OSV advisories. The box score's numbers (CVSS, EPSS, KEV status) are current as of Wednesday, August 19, 2026 UTC and are re-derived as the archive grows; only dated daily editions are immutable pages of record. The authoritative source for this identifier is cve.org.