CVEvulnerability
CVE-2026-97436
- Status
- Received
- Published
- 2026-09-24
- Last modified
- 2026-10-03
- Assigner
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Description
In the Linux kernel, the following vulnerability has been resolved:
dpaa2-switch: rework FDB management on the bridge leave path
On bridge leave, the dpaa2_switch_port_set_fdb() function always
allocates a new FDB for the port which is becoming standalone. In case
no FDB is found, then the port leaving a bridge will continue to use the
current one.
The above logic does not cover the case in which there are multiple
bridges which have ports from the same DPSW instance. In this case, when
the last port leaves bridge #1, it finds an unused FDB to switch to, but
the old FDB is not marked as unused. Since the number of FDBs is equal
to the number of DPSW interfaces, this will eventually lead to multiple
ports sharing the same FDB.
Fix this by changing how we are managing the FDBs on the leave path.
Instead of directly allocating a new FDB, first verify if the current
port is the last one to leave a bridge. If this is the case, then
continue to use the current FDB and only allocate another FDB if there
are other ports remaining in the bridge.
References
- https://git.kernel.org/stable/c/5adbc4d02d7df8bd7aa02c21874f7a582a576b55 git.kernel.org
- https://git.kernel.org/stable/c/abea361a11e4e48695ea149652ef5d3f308b6a49 git.kernel.org
- https://git.kernel.org/stable/c/dc626f2abb3052881911b6166a9425739ce80085 git.kernel.org
- https://git.kernel.org/stable/c/e07ff2338f45adbf572850335d761c2f97545935 git.kernel.org
- https://git.kernel.org/stable/c/ec41bfd281a8bc8027a42d2674eac5b74947ff7a git.kernel.org
- https://git.kernel.org/stable/c/efc1d92eacf03afa6f4d53bf7120e059b6f961f2 git.kernel.org