device property: fix infinite loop in fwnode_for_each_child_node()

Summary

In the Linux kernel, the following vulnerability has been resolved: device property: fix infinite loop in fwnode_for_each_child_node() When iterate over children of a fwnode that has a secondary fwnode, fwnode_get_next_child_node() can enter an infinite loop if the secondary fwnode has more than one child. Parent Child (Primary fwnode) FWa: {FWa1, FWa2, FWa3} (Secondary fwnode) FWb: {FWb1, FWb2} In this case: ┌─> fwnode_get_next_child_node(FWa, FWa1) │ - fwnode_call_ptr_op(FWa, get_next_child_node, FWa1) returns FWa2 │ │ ... │ │ fwnode_get_next_child_node(FWa, FWa3) │ - fwnode_call_ptr_op(FWa, get_next_child_node, FWa3) returns NULL │ - fwnode_call_ptr_op(FWb, get_next_child_node, FWa3) returns FWb1 │ │ fwnode_get_next_child_node(FWa, FWb1) │ - fwnode_call_ptr_op(FWa, get_next_child_node, FWb1) returns FWa1 └────┘ This cause fwnode_for_each_child_node() to loop indefinitely, reapeatedly output {FWa1, FWa2, FWa3, FWb1, FWa1, ...}. The root cause is that when the current child (FWb1) belongs to the secondary fwnode, calling get_next_child_node() on the parimary fwnode incorrectly returns the first child (FWa1) again instead of NULL. Fix this by dynamically checking the parent fwnode of the current child before calling get_next_child_node(). This approach follows the pattern established in commit b5b41ab6b0c1 ("device property: Check fwnode->secondary in fwnode_graph_get_next_endpoint()").

Timeline

1. Sep 11, 2026, 7:46 PM UTCCVE published
2. Oct 19, 2026, 8:51 AM UTCRecord last updated

Affected versions

• Linux Linux

  From 272fcf19fda14ec603ce915aafc56cb3ea2fb38d · fixed in 04004fa33730031392d987a9c1bbd8a0e1c4794b; From 3cfdf8d27b668d122a67a14bf2bcde1a7f10bbd6 · fixed in f4ae79b5f00130aacaddb1f3eb2e5ef711fbf9e0; From 64dc258f9eec1d7204e9879cb836fe29967f1239 · fixed in 20ed517e416df89448029293304c9e180c26cd4b; From 32752c3e81498b106da64a141379eb94f493fe6f · fixed in ba69d892ff4e4a58cc12a2cae106b112db3306cc; From 2692c614f8f05929d692b3dbfd3faef1f00fbaf0 · fixed in 9cb6b223ef02cb5c9777a852ae1ecf5796987eb6; From 2692c614f8f05929d692b3dbfd3faef1f00fbaf0 · fixed in 1900692555826753adab8799a1a8d50bb1ee200c; From 6.1.167 · fixed in 6.1.188; From 6.6.130 · fixed in 6.6.157; From 6.12.78 · fixed in 6.12.109; From 6.18.19 · fixed in 6.18.50; From 5.10.253 · fixed in 5.11; From 5.15.203 · fixed in 5.16; From 6.19.9 · fixed in 6.20

• Linux Linux

  7.0

• KernelLinux

  fixed in 6.1.188; From 6.2.0 · fixed in 6.6.157; From 6.7.0 · fixed in 6.12.109; From 6.13.0 · fixed in 6.18.50; From 6.19.0 · fixed in 7.2.4

References 6