Description
In the Linux kernel, the following vulnerability has been resolved:
scsi: fcoe: Reject FIP descriptors with zero fip_dlen in CVL walker
drivers/scsi/fcoe/fcoe_ctlr.c::fcoe_ctlr_recv_clr_vlink() advanced the
descriptor cursor by an attacker-supplied fip_dlen without ever
requiring dlen >= sizeof(struct fip_desc) in the default branch. The
named descriptor cases (FIP_DT_MAC, FIP_DT_NAME, FIP_DT_VN_ID) checked
their per-type minimum lengths, but a FIP_DT_NON_CRITICAL descriptor
(fip_dtype >= 128, which the standard requires receivers to silently
ignore) skipped that check entirely.
An unauthenticated L2 peer on the FCoE control VLAN could hang
fcoe_ctlr_recv_work on an fcoe, qedf, or bnx2fc initiator indefinitely
by emitting one FIP CVL frame whose single descriptor had fip_dtype ==
FIP_DT_NON_CRITICAL and fip_dlen == 0: the cursor advanced zero bytes
per iteration and the loop condition rlen >= sizeof(*desc) stayed true
forever, blocking every subsequent FIP frame on that controller.
Tighten the outer dlen guard to also reject dlen < sizeof(struct
fip_desc), so a malformed descriptor whose length cannot even cover the
descriptor header is rejected before the switch. This is the same
lower-bound the named cases already apply and is the minimum scope that
closes the loop.
scsi: fcoe: Reject FIP descriptors with zero fip_dlen in CVL walker
drivers/scsi/fcoe/fcoe_ctlr.c::fcoe_ctlr_recv_clr_vlink() advanced the
descriptor cursor by an attacker-supplied fip_dlen without ever
requiring dlen >= sizeof(struct fip_desc) in the default branch. The
named descriptor cases (FIP_DT_MAC, FIP_DT_NAME, FIP_DT_VN_ID) checked
their per-type minimum lengths, but a FIP_DT_NON_CRITICAL descriptor
(fip_dtype >= 128, which the standard requires receivers to silently
ignore) skipped that check entirely.
An unauthenticated L2 peer on the FCoE control VLAN could hang
fcoe_ctlr_recv_work on an fcoe, qedf, or bnx2fc initiator indefinitely
by emitting one FIP CVL frame whose single descriptor had fip_dtype ==
FIP_DT_NON_CRITICAL and fip_dlen == 0: the cursor advanced zero bytes
per iteration and the loop condition rlen >= sizeof(*desc) stayed true
forever, blocking every subsequent FIP frame on that controller.
Tighten the outer dlen guard to also reject dlen < sizeof(struct
fip_desc), so a malformed descriptor whose length cannot even cover the
descriptor header is rejected before the switch. This is the same
lower-bound the named cases already apply and is the minimum scope that
closes the loop.
Published:
2026-07-19
Score:
n/a
EPSS:
n/a
KEV:
No
Impact:
n/a
Action:
n/a
Analysis and contextual insights are available on OpenCVE Cloud.
Remediation
No vendor fix or workaround currently provided.
Additional remediation guidance may be available on OpenCVE Cloud.
Tracking
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Advisories
No advisories yet.
References
History
Sun, 19 Jul 2026 15:30:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| Description | In the Linux kernel, the following vulnerability has been resolved: scsi: fcoe: Reject FIP descriptors with zero fip_dlen in CVL walker drivers/scsi/fcoe/fcoe_ctlr.c::fcoe_ctlr_recv_clr_vlink() advanced the descriptor cursor by an attacker-supplied fip_dlen without ever requiring dlen >= sizeof(struct fip_desc) in the default branch. The named descriptor cases (FIP_DT_MAC, FIP_DT_NAME, FIP_DT_VN_ID) checked their per-type minimum lengths, but a FIP_DT_NON_CRITICAL descriptor (fip_dtype >= 128, which the standard requires receivers to silently ignore) skipped that check entirely. An unauthenticated L2 peer on the FCoE control VLAN could hang fcoe_ctlr_recv_work on an fcoe, qedf, or bnx2fc initiator indefinitely by emitting one FIP CVL frame whose single descriptor had fip_dtype == FIP_DT_NON_CRITICAL and fip_dlen == 0: the cursor advanced zero bytes per iteration and the loop condition rlen >= sizeof(*desc) stayed true forever, blocking every subsequent FIP frame on that controller. Tighten the outer dlen guard to also reject dlen < sizeof(struct fip_desc), so a malformed descriptor whose length cannot even cover the descriptor header is rejected before the switch. This is the same lower-bound the named cases already apply and is the minimum scope that closes the loop. | |
| Title | scsi: fcoe: Reject FIP descriptors with zero fip_dlen in CVL walker | |
| First Time appeared |
Linux
Linux linux Kernel |
|
| CPEs | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* | |
| Vendors & Products |
Linux
Linux linux Kernel |
|
| References |
|
|
Status: PUBLISHED
Assigner: Linux
Published:
Updated: 2026-07-19T14:55:02.195Z
Reserved: 2026-07-19T07:54:57.018Z
Link: CVE-2026-63890
No data.
No data.
No data.
OpenCVE Enrichment
No data.
Weaknesses
No weakness.