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X-Received-From: 2a00:1450:4864:20::444 X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Paolo Bonzini , qemu-devel@nongnu.org, laurent@vivier.eu Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" Richard Henderson writes: > On 1/20/20 1:48 AM, Alex Benn=C3=A9e wrote: >>> + default: >>> + sigsegv: >>=20 >> this label looks a little extraneous. >>=20 >> Otherwise: >>=20 >> Reviewed-by: Alex Benn=C3=A9e >>=20 > > Look a little further down: > >> + default: >> + sigsegv: >> + /* Like force_sig(SIGSEGV). */ >> + gen_signal(env, TARGET_SIGSEGV, TARGET_SI_KERNEL, 0); >> + return; >> + } >> + >> + /* >> + * Validate the return address. >> + * Note that the kernel treats this the same as an invalid entry po= int. >> + */ >> + if (get_user_u64(caller, env->regs[R_ESP])) { >> + goto sigsegv; >> + } Wouldn't this read better: /* * Validate the entry point. We have already validated the page * during translation, now verify the offset. */ switch (env->eip & ~TARGET_PAGE_MASK) { case 0x000: syscall =3D TARGET_NR_gettimeofday; break; case 0x400: syscall =3D TARGET_NR_time; break; case 0x800: syscall =3D TARGET_NR_getcpu; break; default: syscall =3D -1; break; } /* * If we have an invalid entry point or an invalid return address we * generate a SIGSEG. */ if (syscall < 0 || get_user_u64(caller, env->regs[R_ESP])) { gen_signal(env, TARGET_SIGSEGV, TARGET_SI_KERNEL, 0); return; } --=20 Alex Benn=C3=A9e