** Description changed: [Impact] - * Netlink RTM_GETNEIGH requests for PF_BRIDGE are broken since linux + * Netlink RTM_GETNEIGH requests for PF_BRIDGE are broken since linux v4.12. - * Users, tools (e.g., iproute2), and libraries (e.g., go netlink) that use - such request/family currently receive nothing back in the kernel response. + * Users, tools (e.g., iproute2), and libraries (e.g., go netlink) that use + such request/family currently receive nothing back in the kernel response. - * The upstream fix resolves the breakage in the userspace-kernel interface - by explicitly checking for the old/broken request to ensure it's replied. + * The upstream fix resolves the breakage in the userspace-kernel interface + by explicitly checking for the old/broken request to ensure it's replied. [Test Case] - * The command 'ip --family bridge neigh' returns nothing on broken kernels, - and matches 'bridge fdb show' on fixed kernels. + * The command 'ip --family bridge neigh' returns nothing on broken kernels, + and matches 'bridge fdb show' on fixed kernels. - * Before: + * Before: - $ ip --family bridge neigh - $ + $ ip --family bridge neigh + $ - * After: + * After: - $ ip --family bridge neigh - dev ens3 lladdr 33:33:00:00:00:01 PERMANENT - dev ens3 lladdr 01:00:5e:00:00:01 PERMANENT - dev ens3 lladdr 33:33:ff:e9:9d:60 PERMANENT + $ ip --family bridge neigh + dev ens3 lladdr 33:33:00:00:00:01 PERMANENT + dev ens3 lladdr 01:00:5e:00:00:01 PERMANENT + dev ens3 lladdr 33:33:ff:e9:9d:60 PERMANENT - * Reference: + * Reference: - $ bridge fdb show - 33:33:00:00:00:01 dev ens3 self permanent - 01:00:5e:00:00:01 dev ens3 self permanent - 33:33:ff:e9:9d:60 dev ens3 self permanent + $ bridge fdb show + 33:33:00:00:00:01 dev ens3 self permanent + 01:00:5e:00:00:01 dev ens3 self permanent + 33:33:ff:e9:9d:60 dev ens3 self permanent [Regression Potential] - * Low, for three reasons: + * Low, for three reasons: - * The fix is contained in the RTM_GETNEIGH request for PF_BRIDGE family, - which is apparently not very used (this regression has existed between - v4.12 and v4.19). + * The fix is fairly contained (RTM_GETNEIGH request for PF_BRIDGE + family). - * The checks introduced by the fix are conservative, based on the size - of the old request (the size of the old/new requests are different), - and it does nothing different in case the (old) size doesn't match. + * The checks introduced by the fix are conservative, based on the size + of the old request (the size of the old/new requests are different), + and it does nothing different in case the (old) size doesn't match. - * Given the above, only applications with message length and contents - specially hand-crafted (and likely not valid nor useful) might fail. - To the best of my knowledge, this is not the common case out there. + * Given the above, only applications with message length and contents + specially hand-crafted (and likely not valid nor useful) might fail. + To the best of my knowledge, this is not the common case out there. [Other Info] - - * The patch is only applicable to v4.12+ (so not Trusty nor Xenial). - * The patch is the same for Bionic, Cosmic, and unstable. + * The patch is only applicable to v4.12+ (so not Trusty nor Xenial). - * Upstream commit: bd961c9bc664 ("rtnetlink: fix rtnl_fdb_dump() for ndmsg header") - https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=bd961c9bc66497f0c63f4ba1d02900bb85078366 + * The patch is the same for Bionic, Cosmic, and unstable. - * I'll submit the patch shortly to the kernel-team mailing list. + * Upstream commit: bd961c9bc664 ("rtnetlink: fix rtnl_fdb_dump() for ndmsg header") + https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=bd961c9bc66497f0c63f4ba1d02900bb85078366 + + * I'll submit the patch shortly to the kernel-team mailing list.
-- You received this bug notification because you are a member of Kernel Packages, which is subscribed to linux in Ubuntu. https://bugs.launchpad.net/bugs/1796748 Title: regression in 'ip --family bridge neigh' since linux v4.12 Status in linux package in Ubuntu: Incomplete Bug description: [Impact] * Netlink RTM_GETNEIGH requests for PF_BRIDGE are broken since linux v4.12. * Users, tools (e.g., iproute2), and libraries (e.g., go netlink) that use such request/family currently receive nothing back in the kernel response. * The upstream fix resolves the breakage in the userspace-kernel interface by explicitly checking for the old/broken request to ensure it's replied. [Test Case] * The command 'ip --family bridge neigh' returns nothing on broken kernels, and matches 'bridge fdb show' on fixed kernels. * Before: $ ip --family bridge neigh $ * After: $ ip --family bridge neigh dev ens3 lladdr 33:33:00:00:00:01 PERMANENT dev ens3 lladdr 01:00:5e:00:00:01 PERMANENT dev ens3 lladdr 33:33:ff:e9:9d:60 PERMANENT * Reference: $ bridge fdb show 33:33:00:00:00:01 dev ens3 self permanent 01:00:5e:00:00:01 dev ens3 self permanent 33:33:ff:e9:9d:60 dev ens3 self permanent [Regression Potential] * Low, for three reasons: * The fix is fairly contained (RTM_GETNEIGH request for PF_BRIDGE family). * The checks introduced by the fix are conservative, based on the size of the old request (the size of the old/new requests are different), and it does nothing different in case the (old) size doesn't match. * Given the above, only applications with message length and contents specially hand-crafted (and likely not valid nor useful) might fail. To the best of my knowledge, this is not the common case out there. [Other Info] * The patch is only applicable to v4.12+ (so not Trusty nor Xenial). * The patch is the same for Bionic, Cosmic, and unstable. * Upstream commit: bd961c9bc664 ("rtnetlink: fix rtnl_fdb_dump() for ndmsg header") https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=bd961c9bc66497f0c63f4ba1d02900bb85078366 * I'll submit the patch shortly to the kernel-team mailing list. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1796748/+subscriptions -- Mailing list: https://launchpad.net/~kernel-packages Post to : kernel-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~kernel-packages More help : https://help.launchpad.net/ListHelp