[streams] Bound user stream wrapper recursion with a depth counter - #262
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iliaal wants to merge 1 commit into
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[streams] Bound user stream wrapper recursion with a depth counter#262iliaal wants to merge 1 commit into
iliaal wants to merge 1 commit into
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The userspace wrapper recursion guard only compared the filename being opened against the currently open one, so a wrapper whose stream_open() opens a different path at every level (e.g. an incrementing counter in the URL) recursed without bound and exhausted the C stack. Add a per-request nesting depth counter shared by user_wrapper_opener() and user_wrapper_opendir(), rejecting opens beyond 64 nested levels with the existing "infinite recursion prevented" error. Sibling audit: no other entry point nests user-wrapper opens; stat/unlink/rename/mkdir/rmdir and metadata handlers do not recurse through fopen/opendir.
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The userspace stream wrapper recursion guard only compared the filename being opened against the currently open one, so a wrapper whose stream_open() opens a different path at every level (for example an incrementing counter embedded in the URL) recursed without bound and exhausted the C stack. This adds a per-request nesting depth counter shared by user_wrapper_opener() and user_wrapper_opendir() that rejects opens beyond 64 nested levels with the existing "infinite recursion prevented" error, keeping the filename comparison for direct self-recursion. Sibling audit found no other entry point that nests user-wrapper opens through fopen/opendir.