Description
In the Linux kernel, the following vulnerability has been resolved: bpf: Check ancestor frames for rbtree callbacks bpf_rbtree_add() invokes its comparator while the caller holds the root lock. The native insertion code retains raw parent and link pointers across the callback, so the verifier prohibits unlocking, consuming tree nodes, or changing RCU state from that callback. in_rbtree_lock_required_cb() only checks the innermost verifier frame. Static subprogram calls are permitted while holding a spin lock, and such a call pushes a frame without in_callback_fn set. Consequently, all callback restrictions disappear in the nested frame. The subprogram can unlock the tree, remove and drop the node being compared, then relock. Native insertion resumes with the stale parent pointer and links freed memory into the tree. Walk all active frames for the rbtree callback instead. Benign static subprograms remain permitted, while callback restrictions follow execution into nested frames.
Affected products
Version statuses are supplied by the assigning organization. Consult the original record for detailed ranges and platform conditions.
Linux Linux
Default version status: unaffected
a44b1334aadd82203f661adb9adb41e53ad0e8d1 to < 252e9b476af723edd299a5c71c389ec018e46656affecteda44b1334aadd82203f661adb9adb41e53ad0e8d1 to < b545fa447e09e6844868deb2bee228827fe54d15affecteda44b1334aadd82203f661adb9adb41e53ad0e8d1 to < 2410cb2ac0416dd2795a81984c8c73d7250bd8c4affecteda44b1334aadd82203f661adb9adb41e53ad0e8d1 to < 369f4ce734570bdfedaa4b5ca50e2a3f6a892728affected
Linux Linux
Default version status: affected
6.9affected0 to < 6.9unaffected6.12.114 to ≤ 6.12.*unaffected6.18.53 to ≤ 6.18.*unaffected7.2.7 to ≤ 7.2.*unaffected7.3 to ≤ *unaffected