CVE-2026-98807: net/mlx5: Fix slab-out-of-bounds when handling team device events

Severity: unknown
Exploited in the wild: not listed in CISA KEV
EPSS: 0.2% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-10-18 · updated 2026-10-19

Description

In the Linux kernel, the following vulnerability has been resolved: net/mlx5: Fix slab-out-of-bounds when handling team device events The mlx5_handle_changeupper_event() and mlx5_handle_changeinfodata_event() functions check for LAG masters (which includes both bonding and team devices) but only call bonding-specific APIs. When processing team device events, calling bond_slave_get_rcu() and bond_is_slave_inactive() on team_port structures causes KASAN to detect an out-of-bounds memory access since team_port is smaller than bond slave. Fix this by wrapping the bond-specific API calls with a check for bonding devices. This allows the function to still process LAG events for both bonding and teams but only calls bond-specific functions when dealing with actual bonding devices. For mlx5_handle_changeinfodata_event(), keep the explicit bond check as mlx5 doesn't handle state information for team ports anyway. Tested with Mellanox ConnectX-5 on Linux 7.2.0-rc6: - Bonding: PASS (no regressions) - Team device: PASS (no KASAN errors)

Affected products

Linux kernel: 5.18 — fixed in 7.3

How to fix

Upgrade to a fixed version: Linux kernel 7.3. Check the vendor advisory for mitigations.

References

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