[http] Fix out-of-bounds read on empty Location header - #270
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sapi_cli_server_send_headers() sent the header buffer through php_cli_server_client_send_through() but dropped the return value, so it always reported SAPI_HEADER_SENT_SUCCESSFULLY, even when the send failed and php_handle_aborted_connection() did not bail out (ignore_user_abort=1). It now compares the send result against the buffer length and returns SAPI_HEADER_SEND_FAILED when it comes up short. php_cli_server_client_send_through() itself returned the number of bytes left on failure, which equals str_len when nothing was sent: the same value it returns on success. It now returns the number of bytes actually sent on both paths. Since sapi_send_headers() resets headers_sent on SAPI_HEADER_SEND_FAILED, a headers_written flag on the client guards against rebuilding and resending the whole header block on every subsequent output write. Close phpGH-23428
…ams (php#23282) Keep the native archive state alive independently of the ZipArchive object, allowing streams to remain valid without retaining the object itself.
uloc_getKeywordValue failure destroyed the result array and returned without uenum_close(). Close the enumeration on that path. The success path already closes it. Audited the other uenum_close site in this file (acceptLanguage). Closes phpGH-23351
An empty Location header allocates a single byte for the NUL terminator, so reading location[1] in the relative-redirect branch over-reads heap memory and could append a garbage-derived path to the redirect target instead of the correct host root. Guard the read with location_len before dereferencing the second byte. Sibling audit: no other unguarded indexing of header_info.location exists; all other uses are length-safe (strlen/strncasecmp/spprintf).
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Promoted as php#23467. |
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When a server sends a redirect with an empty Location header, the wrapper allocates a single byte for it and the relative-redirect branch then reads location[1], one byte past the allocation. A hostile server can make that over-read pick up heap garbage so the redirect target becomes the current path plus junk instead of the correct host root, which is observable as spurious slashes or arbitrary bytes appended to the followed URL on every hop. The fix guards the dereference of the second byte with header_info.location_len before reading it, so an empty Location now deterministically redirects to the host root. A sibling audit found no other unguarded indexing of header_info.location; all remaining uses are length-safe (strlen/strncasecmp/spprintf). Adds ext/standard/tests/http/http_empty_location_redirect.phpt which fails on the unpatched build with a garbage-appended redirect path and passes after the fix.