Fix GH-21006: JIT SEGV with FETCH_OBJ_FUNC_ARG and property hooks#21369
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iliaal wants to merge 1 commit intophp:masterfrom
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Fix GH-21006: JIT SEGV with FETCH_OBJ_FUNC_ARG and property hooks#21369iliaal wants to merge 1 commit intophp:masterfrom
iliaal wants to merge 1 commit intophp:masterfrom
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When the JIT falls back to the VM handler for FETCH_OBJ_FUNC_ARG (or FETCH_OBJ_R), the handler may find the SIMPLE_GET flag set in the runtime cache for a hooked property. This causes it to push a call frame for the hook function, changing execute_data. When the trace resumes after the handler returns, it continues with the wrong execute_data, leading to a segfault on the next opcode that accesses EX(call). Fix by emitting IR code in zend_jit_trace_handler() to clear the SIMPLE_GET flag in the runtime cache before calling the VM handler, so it falls through to read_property instead.
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Summary
FETCH_OBJ_FUNC_ARG(orFETCH_OBJ_R), the handler may find theSIMPLE_GETflag set in the runtime cache for a hooked property. This causes it to push a call frame for the hook function, changingexecute_data. When the trace resumes, it continues with the wrongexecute_data, leading to a segfault.zend_jit_trace_handler()to clear theSIMPLE_GETflag before calling the VM handler, so it falls through toread_propertyinstead.Closes GH-21006