In the Linux kernel, the following vulnerability has been resolved: SUNRPC: Fix the svc_deferred_event trace class Fix a NULL deref crash that occurs when an svc_rqst is deferred while the sunrpc tracing subsystem is enabled. svc_revisit() sets dr->xprt to NULL, so it can't be relied upon in the tracepoint to provide the remote's address. Unfortunately we can't revert the "svc_deferred_class" hunk in commit ece200ddd54b ("sunrpc: Save remote presentation address in svc_xprt for trace events") because there is now a specific check of event format specifiers for unsafe dereferences. The warning that check emits is: event svc_defer_recv has unsafe dereference of argument 1 A "%pISpc" format specifier with a "struct sockaddr *" is indeed flagged by this check. Instead, take the brute-force approach used by the svcrdma_qp_error tracepoint. Convert the dr::addr field into a presentation address in the TP_fast_assign() arm of the trace event, and store that as a string. This fix can be backported to -stable kernels. In the meantime, commit c6ced22997ad ("tracing: Update print fmt check to handle new __get_sockaddr() macro") is now in v5.18, so this wonky fix can be replaced with __sockaddr() and friends properly during the v5.19 merge window.
| Métrique | Valeur | Interprétation |
|---|---|---|
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AV (Vecteur d'Attaque)
Attack Vector
|
Local (L)
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Exploit nécessite un accès local au système |
|
AC (Complexité d'Attaque)
Attack Complexity
|
Low (L)
|
Peu de conditions requises pour exploiter |
|
PR (Privilèges Requis)
Privileges Required
|
Low (L)
|
Authentifié avec compte utilisateur basique |
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UI (Interaction Utilisateur)
User Interaction
|
None (N)
|
Aucune interaction utilisateur nécessaire |
|
S (Périmètre)
Scope
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Unchanged (U)
|
Impact reste dans le périmètre du composant compromis |
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C (Impact Confidentialité)
Confidentiality Impact
|
None (N)
|
Aucune divulgation d'informations |
|
I (Impact Intégrité)
Integrity Impact
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None (N)
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Aucune modification de données possible |
|
A (Impact Disponibilité)
Availability Impact
|
High (H)
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Interruption totale du service possible |
SUNRPC: Fix the svc_deferred_event trace class