ipam: Fix revert logic in reuseIPNets causing v4 CIDR duplication#44832
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christarazi merged 1 commit intocilium:mainfrom Mar 18, 2026
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/test Edit: #44407 |
tklauser
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Looks good to me. One non-blocking question/suggestion inline.
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When reuseIPNets processes a node with a pre-existing duplicate v6 CIDR, the v6 allocation fails with ErrCIDRAllocated. The revertStack.Revert() then releases the successfully-occupied v4 CIDR as well. Because the updated node object is never synced to the internal state but its CiliumNode spec still references the v4 CIDR, allocateNext can hand the same v4 CIDR to another node. The fix is to handle ErrCIDRAllocated per IP family. That means: * Keeping the successful family's allocation * Adding the node to n.nodes with partial CIDRs * Return the error so allocateNode can report it in the CiliumNode status Also make upsertLocked() detect spec changes so k8s can be updated instead of only updating the status only. Co-authored-by: André Martins <andre@cilium.io> Signed-off-by: Chris Tarazi <chris@isovalent.com>
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This was referenced Mar 18, 2026
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When reuseIPNets processes a node with a pre-existing duplicate v6 CIDR,
the v6 allocation fails with ErrCIDRAllocated. The revertStack.Revert()
then releases the successfully-occupied v4 CIDR as well. Because the
updated node object is never synced to the internal state but its
CiliumNode spec still references the v4 CIDR, allocateNext can hand the
same v4 CIDR to another node.
The fix is to handle ErrCIDRAllocated per IP family. That means:
status
Also make upsertLocked() detect spec changes so k8s can be updated
instead of only updating the status only.