From 317a33b6ebad8a9e94109b4421804f7945eb8935 Mon Sep 17 00:00:00 2001 From: Richard Henderson Date: Wed, 29 Sep 2021 09:05:42 -0400 Subject: [PATCH] linux-user/mips: Implement setup_sigtramp MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Create and record the two signal trampolines. Reviewed-by: Philippe Mathieu-Daudé Signed-off-by: Richard Henderson Message-Id: <20210929130553.121567-16-richard.henderson@linaro.org> Signed-off-by: Laurent Vivier --- linux-user/mips/signal.c | 34 ++++++++++++++++++++++--------- linux-user/mips/target_signal.h | 1 + linux-user/mips64/target_signal.h | 2 ++ 3 files changed, 27 insertions(+), 10 deletions(-) diff --git a/linux-user/mips/signal.c b/linux-user/mips/signal.c index 64072779b9..8f79e405ec 100644 --- a/linux-user/mips/signal.c +++ b/linux-user/mips/signal.c @@ -209,8 +209,6 @@ void setup_frame(int sig, struct target_sigaction * ka, goto give_sigsegv; } - install_sigtramp(frame->sf_code, TARGET_NR_sigreturn); - setup_sigcontext(regs, &frame->sf_sc); for(i = 0; i < TARGET_NSIG_WORDS; i++) { @@ -231,7 +229,7 @@ void setup_frame(int sig, struct target_sigaction * ka, regs->active_tc.gpr[ 5] = 0; regs->active_tc.gpr[ 6] = frame_addr + offsetof(struct sigframe, sf_sc); regs->active_tc.gpr[29] = frame_addr; - regs->active_tc.gpr[31] = frame_addr + offsetof(struct sigframe, sf_code); + regs->active_tc.gpr[31] = default_sigreturn; /* The original kernel code sets CP0_EPC to the handler * since it returns to userland using eret * we cannot do this here, and we must set PC directly */ @@ -305,8 +303,6 @@ void setup_rt_frame(int sig, struct target_sigaction *ka, goto give_sigsegv; } - install_sigtramp(frame->rs_code, TARGET_NR_rt_sigreturn); - tswap_siginfo(&frame->rs_info, info); __put_user(0, &frame->rs_uc.tuc_flags); @@ -335,11 +331,13 @@ void setup_rt_frame(int sig, struct target_sigaction *ka, env->active_tc.gpr[ 6] = frame_addr + offsetof(struct target_rt_sigframe, rs_uc); env->active_tc.gpr[29] = frame_addr; - env->active_tc.gpr[31] = frame_addr - + offsetof(struct target_rt_sigframe, rs_code); - /* The original kernel code sets CP0_EPC to the handler - * since it returns to userland using eret - * we cannot do this here, and we must set PC directly */ + env->active_tc.gpr[31] = default_rt_sigreturn; + + /* + * The original kernel code sets CP0_EPC to the handler + * since it returns to userland using eret + * we cannot do this here, and we must set PC directly + */ env->active_tc.PC = env->active_tc.gpr[25] = ka->_sa_handler; mips_set_hflags_isa_mode_from_pc(env); unlock_user_struct(frame, frame_addr, 1); @@ -379,3 +377,19 @@ badframe: force_sig(TARGET_SIGSEGV); return -TARGET_QEMU_ESIGRETURN; } + +void setup_sigtramp(abi_ulong sigtramp_page) +{ + uint32_t *tramp = lock_user(VERIFY_WRITE, sigtramp_page, 2 * 8, 0); + assert(tramp != NULL); + +#ifdef TARGET_ARCH_HAS_SETUP_FRAME + default_sigreturn = sigtramp_page; + install_sigtramp(tramp, TARGET_NR_sigreturn); +#endif + + default_rt_sigreturn = sigtramp_page + 8; + install_sigtramp(tramp + 2, TARGET_NR_rt_sigreturn); + + unlock_user(tramp, sigtramp_page, 2 * 8); +} diff --git a/linux-user/mips/target_signal.h b/linux-user/mips/target_signal.h index d521765f6b..780a4ddf29 100644 --- a/linux-user/mips/target_signal.h +++ b/linux-user/mips/target_signal.h @@ -73,6 +73,7 @@ typedef struct target_sigaltstack { /* compare linux/arch/mips/kernel/signal.c:setup_frame() */ #define TARGET_ARCH_HAS_SETUP_FRAME #endif +#define TARGET_ARCH_HAS_SIGTRAMP_PAGE 1 /* bit-flags */ #define TARGET_SS_AUTODISARM (1U << 31) /* disable sas during sighandling */ diff --git a/linux-user/mips64/target_signal.h b/linux-user/mips64/target_signal.h index d857c55e4c..275e9b7f9a 100644 --- a/linux-user/mips64/target_signal.h +++ b/linux-user/mips64/target_signal.h @@ -76,4 +76,6 @@ typedef struct target_sigaltstack { /* compare linux/arch/mips/kernel/signal.c:setup_frame() */ #define TARGET_ARCH_HAS_SETUP_FRAME #endif +#define TARGET_ARCH_HAS_SIGTRAMP_PAGE 1 + #endif /* MIPS64_TARGET_SIGNAL_H */