From 495dfbf767553980dbd40a19a96a8ca5fa1be616 Mon Sep 17 00:00:00 2001 From: Al Viro Date: Tue, 25 Dec 2012 19:09:45 -0500 Subject: generic sys_sigaction() and compat_sys_sigaction() conditional on OLD_SIGACTION/COMPAT_OLD_SIGACTION Signed-off-by: Al Viro --- arch/Kconfig | 11 +++++++ include/linux/compat.h | 14 +++++++++ include/linux/signal.h | 9 ++++++ include/linux/syscalls.h | 5 ++++ kernel/signal.c | 78 ++++++++++++++++++++++++++++++++++++++++++++++++ 5 files changed, 117 insertions(+) diff --git a/arch/Kconfig b/arch/Kconfig index 3b4a416..e50d3af 100644 --- a/arch/Kconfig +++ b/arch/Kconfig @@ -400,4 +400,15 @@ config OLD_SIGSUSPEND3 help Even weirder antique ABI - three-argument sigsuspend(2) +config OLD_SIGACTION + bool + help + Architecture has old sigaction(2) syscall. Nope, not the same + as OLD_SIGSUSPEND | OLD_SIGSUSPEND3 - alpha has sigsuspend(2), + but fairly different variant of sigaction(2), thanks to OSF/1 + compatibility... + +config COMPAT_OLD_SIGACTION + bool + source "kernel/gcov/Kconfig" diff --git a/include/linux/compat.h b/include/linux/compat.h index 0d53ab4..e20b8b4 100644 --- a/include/linux/compat.h +++ b/include/linux/compat.h @@ -299,6 +299,15 @@ struct compat_robust_list_head { compat_uptr_t list_op_pending; }; +#ifdef CONFIG_COMPAT_OLD_SIGACTION +struct compat_old_sigaction { + compat_uptr_t sa_handler; + compat_old_sigset_t sa_mask; + compat_ulong_t sa_flags; + compat_uptr_t sa_restorer; +}; +#endif + struct compat_statfs; struct compat_statfs64; struct compat_old_linux_dirent; @@ -383,6 +392,11 @@ int get_compat_sigevent(struct sigevent *event, const struct compat_sigevent __user *u_event); long compat_sys_rt_tgsigqueueinfo(compat_pid_t tgid, compat_pid_t pid, int sig, struct compat_siginfo __user *uinfo); +#ifdef CONFIG_COMPAT_OLD_SIGACTION +asmlinkage long compat_sys_sigaction(int sig, + const struct compat_old_sigaction __user *act, + struct compat_old_sigaction __user *oact); +#endif static inline int compat_timeval_compare(struct compat_timeval *lhs, struct compat_timeval *rhs) diff --git a/include/linux/signal.h b/include/linux/signal.h index 0b6878e..e28e8d4 100644 --- a/include/linux/signal.h +++ b/include/linux/signal.h @@ -269,6 +269,15 @@ struct k_sigaction { __sigrestore_t ka_restorer; #endif }; + +#ifdef CONFIG_OLD_SIGACTION +struct old_sigaction { + __sighandler_t sa_handler; + old_sigset_t sa_mask; + unsigned long sa_flags; + __sigrestore_t sa_restorer; +}; +#endif extern int get_signal_to_deliver(siginfo_t *info, struct k_sigaction *return_ka, struct pt_regs *regs, void *cookie); extern void signal_delivered(int sig, siginfo_t *info, struct k_sigaction *ka, struct pt_regs *regs, int stepping); diff --git a/include/linux/syscalls.h b/include/linux/syscalls.h index 1c4938b..02b0450 100644 --- a/include/linux/syscalls.h +++ b/include/linux/syscalls.h @@ -385,6 +385,11 @@ asmlinkage long sys_sigsuspend(old_sigset_t mask); asmlinkage long sys_sigsuspend(int unused1, int unused2, old_sigset_t mask); #endif +#ifdef CONFIG_OLD_SIGACTION +asmlinkage long sys_sigaction(int, const struct old_sigaction __user *, + struct old_sigaction __user *); +#endif + #ifndef CONFIG_ODD_RT_SIGACTION asmlinkage long sys_rt_sigaction(int, const struct sigaction __user *, diff --git a/kernel/signal.c b/kernel/signal.c index f3665f3..79998f5 100644 --- a/kernel/signal.c +++ b/kernel/signal.c @@ -3409,6 +3409,84 @@ COMPAT_SYSCALL_DEFINE4(rt_sigaction, int, sig, #endif #endif /* !CONFIG_ODD_RT_SIGACTION */ +#ifdef CONFIG_OLD_SIGACTION +SYSCALL_DEFINE3(sigaction, int, sig, + const struct old_sigaction __user *, act, + struct old_sigaction __user *, oact) +{ + struct k_sigaction new_ka, old_ka; + int ret; + + if (act) { + old_sigset_t mask; + if (!access_ok(VERIFY_READ, act, sizeof(*act)) || + __get_user(new_ka.sa.sa_handler, &act->sa_handler) || + __get_user(new_ka.sa.sa_restorer, &act->sa_restorer) || + __get_user(new_ka.sa.sa_flags, &act->sa_flags) || + __get_user(mask, &act->sa_mask)) + return -EFAULT; +#ifdef __ARCH_HAS_KA_RESTORER + new_ka.ka_restorer = NULL; +#endif + siginitset(&new_ka.sa.sa_mask, mask); + } + + ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL); + + if (!ret && oact) { + if (!access_ok(VERIFY_WRITE, oact, sizeof(*oact)) || + __put_user(old_ka.sa.sa_handler, &oact->sa_handler) || + __put_user(old_ka.sa.sa_restorer, &oact->sa_restorer) || + __put_user(old_ka.sa.sa_flags, &oact->sa_flags) || + __put_user(old_ka.sa.sa_mask.sig[0], &oact->sa_mask)) + return -EFAULT; + } + + return ret; +} +#endif +#ifdef CONFIG_COMPAT_OLD_SIGACTION +COMPAT_SYSCALL_DEFINE3(sigaction, int, sig, + const struct compat_old_sigaction __user *, act, + struct compat_old_sigaction __user *, oact) +{ + struct k_sigaction new_ka, old_ka; + int ret; + compat_old_sigset_t mask; + compat_uptr_t handler, restorer; + + if (act) { + if (!access_ok(VERIFY_READ, act, sizeof(*act)) || + __get_user(handler, &act->sa_handler) || + __get_user(restorer, &act->sa_restorer) || + __get_user(new_ka.sa.sa_flags, &act->sa_flags) || + __get_user(mask, &act->sa_mask)) + return -EFAULT; + +#ifdef __ARCH_HAS_KA_RESTORER + new_ka.ka_restorer = NULL; +#endif + new_ka.sa.sa_handler = compat_ptr(handler); + new_ka.sa.sa_restorer = compat_ptr(restorer); + siginitset(&new_ka.sa.sa_mask, mask); + } + + ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL); + + if (!ret && oact) { + if (!access_ok(VERIFY_WRITE, oact, sizeof(*oact)) || + __put_user(ptr_to_compat(old_ka.sa.sa_handler), + &oact->sa_handler) || + __put_user(ptr_to_compat(old_ka.sa.sa_restorer), + &oact->sa_restorer) || + __put_user(old_ka.sa.sa_flags, &oact->sa_flags) || + __put_user(old_ka.sa.sa_mask.sig[0], &oact->sa_mask)) + return -EFAULT; + } + return ret; +} +#endif + #ifdef __ARCH_WANT_SYS_SGETMASK /* -- cgit v1.1