ta: apply __no_stack_protector to __ta_entry() or __ta_entry_c()

Apply the __no_stack_protector attribute to the first C function called
following the TA entry point (i.e., __ta_entry(), or for the special
case of ARM32, __ta_entry_c()). This is required because
__stack_chk_guard is initialized in this very function, therefore stack
protection cannot be assumed to be functional at this point.

Fixes a TA crash on QEMUv7 with Clang 18.1.7 [1].

Link: #7047 [1]
Signed-off-by: Jerome Forissier <[email protected]>
Acked-by: Etienne Carriere <[email protected]>
Acked-by: Jens Wiklander <[email protected]>
Reviewed-by: Khoa Hoang <[email protected]>

ta/user_ta_header.c

@@ -39,15 +39,17 @@ struct utee_params;
 TEE_Result __utee_entry(unsigned long func, unsigned long session_id,
 			struct utee_params *up, unsigned long cmd_id);
 
-void __noreturn _C_FUNCTION(__ta_entry)(unsigned long func,
-					unsigned long session_id,
-					struct utee_params *up,
-					unsigned long cmd_id);
-
-void __noreturn _C_FUNCTION(__ta_entry)(unsigned long func,
-					unsigned long session_id,
-					struct utee_params *up,
-					unsigned long cmd_id)
+void __noreturn __no_stack_protector
+_C_FUNCTION(__ta_entry)(unsigned long func,
+			unsigned long session_id,
+			struct utee_params *up,
+			unsigned long cmd_id);
+
+void __noreturn __no_stack_protector
+_C_FUNCTION(__ta_entry)(unsigned long func,
+			unsigned long session_id,
+			struct utee_params *up,
+			unsigned long cmd_id)
 {
 	static bool stack_canary_inited;
 	TEE_Result res = TEE_ERROR_GENERIC;