From: Al Viro Date: Fri, 14 Dec 2012 19:47:53 +0000 (-0500) Subject: generic compat_sys_sigaltstack() X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=9026843952adac5b123c7b8dc961e5c15828d9e1;p=GitHub%2FLineageOS%2Fandroid_kernel_motorola_exynos9610.git generic compat_sys_sigaltstack() Again, conditional on CONFIG_GENERIC_SIGALTSTACK Signed-off-by: Al Viro --- diff --git a/arch/x86/ia32/ia32_signal.c b/arch/x86/ia32/ia32_signal.c index efc6a958b71d..a866411a2fcc 100644 --- a/arch/x86/ia32/ia32_signal.c +++ b/arch/x86/ia32/ia32_signal.c @@ -136,52 +136,6 @@ asmlinkage long sys32_sigsuspend(int history0, int history1, old_sigset_t mask) return sigsuspend(&blocked); } -asmlinkage long sys32_sigaltstack(const stack_ia32_t __user *uss_ptr, - stack_ia32_t __user *uoss_ptr, - struct pt_regs *regs) -{ - stack_t uss, uoss; - int ret, err = 0; - mm_segment_t seg; - - if (uss_ptr) { - u32 ptr; - - memset(&uss, 0, sizeof(stack_t)); - if (!access_ok(VERIFY_READ, uss_ptr, sizeof(stack_ia32_t))) - return -EFAULT; - - get_user_try { - get_user_ex(ptr, &uss_ptr->ss_sp); - get_user_ex(uss.ss_flags, &uss_ptr->ss_flags); - get_user_ex(uss.ss_size, &uss_ptr->ss_size); - } get_user_catch(err); - - if (err) - return -EFAULT; - uss.ss_sp = compat_ptr(ptr); - } - seg = get_fs(); - set_fs(KERNEL_DS); - ret = do_sigaltstack((stack_t __force __user *) (uss_ptr ? &uss : NULL), - (stack_t __force __user *) &uoss, regs->sp); - set_fs(seg); - if (ret >= 0 && uoss_ptr) { - if (!access_ok(VERIFY_WRITE, uoss_ptr, sizeof(stack_ia32_t))) - return -EFAULT; - - put_user_try { - put_user_ex(ptr_to_compat(uoss.ss_sp), &uoss_ptr->ss_sp); - put_user_ex(uoss.ss_flags, &uoss_ptr->ss_flags); - put_user_ex(uoss.ss_size, &uoss_ptr->ss_size); - } put_user_catch(err); - - if (err) - ret = -EFAULT; - } - return ret; -} - /* * Do a signal return; undo the signal stack. */ @@ -292,7 +246,6 @@ asmlinkage long sys32_rt_sigreturn(struct pt_regs *regs) struct rt_sigframe_ia32 __user *frame; sigset_t set; unsigned int ax; - struct pt_regs tregs; frame = (struct rt_sigframe_ia32 __user *)(regs->sp - 4); @@ -306,8 +259,7 @@ asmlinkage long sys32_rt_sigreturn(struct pt_regs *regs) if (ia32_restore_sigcontext(regs, &frame->uc.uc_mcontext, &ax)) goto badframe; - tregs = *regs; - if (sys32_sigaltstack(&frame->uc.uc_stack, NULL, &tregs) == -EFAULT) + if (compat_restore_altstack(&frame->uc.uc_stack)) goto badframe; return ax; diff --git a/arch/x86/ia32/ia32entry.S b/arch/x86/ia32/ia32entry.S index 32e6f05ddaaa..102ff7cb3e41 100644 --- a/arch/x86/ia32/ia32entry.S +++ b/arch/x86/ia32/ia32entry.S @@ -464,7 +464,6 @@ GLOBAL(\label) PTREGSCALL stub32_rt_sigreturn, sys32_rt_sigreturn, %rdi PTREGSCALL stub32_sigreturn, sys32_sigreturn, %rdi - PTREGSCALL stub32_sigaltstack, sys32_sigaltstack, %rdx PTREGSCALL stub32_execve, compat_sys_execve, %rcx PTREGSCALL stub32_fork, sys_fork, %rdi PTREGSCALL stub32_vfork, sys_vfork, %rdi diff --git a/arch/x86/include/asm/ia32.h b/arch/x86/include/asm/ia32.h index e6232773ce49..4c6da2e4bb1d 100644 --- a/arch/x86/include/asm/ia32.h +++ b/arch/x86/include/asm/ia32.h @@ -29,16 +29,10 @@ struct old_sigaction32 { unsigned int sa_restorer; /* Another 32 bit pointer */ }; -typedef struct sigaltstack_ia32 { - unsigned int ss_sp; - int ss_flags; - unsigned int ss_size; -} stack_ia32_t; - struct ucontext_ia32 { unsigned int uc_flags; unsigned int uc_link; - stack_ia32_t uc_stack; + compat_stack_t uc_stack; struct sigcontext_ia32 uc_mcontext; compat_sigset_t uc_sigmask; /* mask last for extensibility */ }; @@ -46,7 +40,7 @@ struct ucontext_ia32 { struct ucontext_x32 { unsigned int uc_flags; unsigned int uc_link; - stack_ia32_t uc_stack; + compat_stack_t uc_stack; unsigned int uc__pad0; /* needed for alignment */ struct sigcontext uc_mcontext; /* the 64-bit sigcontext type */ compat_sigset_t uc_sigmask; /* mask last for extensibility */ diff --git a/arch/x86/include/asm/sys_ia32.h b/arch/x86/include/asm/sys_ia32.h index c76fae4d90be..31f61f96e0fb 100644 --- a/arch/x86/include/asm/sys_ia32.h +++ b/arch/x86/include/asm/sys_ia32.h @@ -69,8 +69,6 @@ asmlinkage long sys32_fallocate(int, int, unsigned, /* ia32/ia32_signal.c */ asmlinkage long sys32_sigsuspend(int, int, old_sigset_t); -asmlinkage long sys32_sigaltstack(const stack_ia32_t __user *, - stack_ia32_t __user *, struct pt_regs *); asmlinkage long sys32_sigreturn(struct pt_regs *); asmlinkage long sys32_rt_sigreturn(struct pt_regs *); diff --git a/arch/x86/kernel/entry_64.S b/arch/x86/kernel/entry_64.S index 6e462019f195..86d81199bbde 100644 --- a/arch/x86/kernel/entry_64.S +++ b/arch/x86/kernel/entry_64.S @@ -912,8 +912,6 @@ ENTRY(stub_rt_sigreturn) END(stub_rt_sigreturn) #ifdef CONFIG_X86_X32_ABI - PTREGSCALL stub_x32_sigaltstack, sys32_sigaltstack, %rdx - ENTRY(stub_x32_rt_sigreturn) CFI_STARTPROC addq $8, %rsp diff --git a/arch/x86/kernel/signal.c b/arch/x86/kernel/signal.c index 16d065c23baf..b17ed37c61a2 100644 --- a/arch/x86/kernel/signal.c +++ b/arch/x86/kernel/signal.c @@ -857,7 +857,6 @@ asmlinkage long sys32_x32_rt_sigreturn(struct pt_regs *regs) struct rt_sigframe_x32 __user *frame; sigset_t set; unsigned long ax; - struct pt_regs tregs; frame = (struct rt_sigframe_x32 __user *)(regs->sp - 8); @@ -871,8 +870,7 @@ asmlinkage long sys32_x32_rt_sigreturn(struct pt_regs *regs) if (restore_sigcontext(regs, &frame->uc.uc_mcontext, &ax)) goto badframe; - tregs = *regs; - if (sys32_sigaltstack(&frame->uc.uc_stack, NULL, &tregs) == -EFAULT) + if (compat_restore_altstack(&frame->uc.uc_stack)) goto badframe; return ax; diff --git a/arch/x86/syscalls/syscall_32.tbl b/arch/x86/syscalls/syscall_32.tbl index 62c7b222e45c..235226efaa7f 100644 --- a/arch/x86/syscalls/syscall_32.tbl +++ b/arch/x86/syscalls/syscall_32.tbl @@ -192,7 +192,7 @@ 183 i386 getcwd sys_getcwd 184 i386 capget sys_capget 185 i386 capset sys_capset -186 i386 sigaltstack sys_sigaltstack stub32_sigaltstack +186 i386 sigaltstack sys_sigaltstack compat_sys_sigaltstack 187 i386 sendfile sys_sendfile sys32_sendfile 188 i386 getpmsg 189 i386 putpmsg diff --git a/arch/x86/syscalls/syscall_64.tbl b/arch/x86/syscalls/syscall_64.tbl index 6ffa7f9d005e..c68cbe7174e7 100644 --- a/arch/x86/syscalls/syscall_64.tbl +++ b/arch/x86/syscalls/syscall_64.tbl @@ -337,7 +337,7 @@ 522 x32 rt_sigpending sys32_rt_sigpending 523 x32 rt_sigtimedwait compat_sys_rt_sigtimedwait 524 x32 rt_sigqueueinfo sys32_rt_sigqueueinfo -525 x32 sigaltstack stub_x32_sigaltstack +525 x32 sigaltstack compat_sys_sigaltstack 526 x32 timer_create compat_sys_timer_create 527 x32 mq_notify compat_sys_mq_notify 528 x32 kexec_load compat_sys_kexec_load diff --git a/include/linux/compat.h b/include/linux/compat.h index 62bb76f91baf..cb5637e2ee2c 100644 --- a/include/linux/compat.h +++ b/include/linux/compat.h @@ -68,6 +68,16 @@ #ifndef compat_user_stack_pointer #define compat_user_stack_pointer() current_user_stack_pointer() #endif +#ifdef CONFIG_GENERIC_SIGALTSTACK +#ifndef compat_sigaltstack /* we'll need that for MIPS */ +typedef struct compat_sigaltstack { + compat_uptr_t ss_sp; + int ss_flags; + compat_size_t ss_size; +} compat_stack_t; +#endif +#endif + #define compat_jiffies_to_clock_t(x) \ (((unsigned long)(x) * COMPAT_USER_HZ) / HZ) @@ -632,6 +642,12 @@ asmlinkage ssize_t compat_sys_process_vm_writev(compat_pid_t pid, asmlinkage long compat_sys_sendfile(int out_fd, int in_fd, compat_off_t __user *offset, compat_size_t count); +#ifdef CONFIG_GENERIC_SIGALTSTACK +asmlinkage long compat_sys_sigaltstack(const compat_stack_t __user *uss_ptr, + compat_stack_t __user *uoss_ptr); + +int compat_restore_altstack(const compat_stack_t __user *uss); +#endif #else diff --git a/kernel/signal.c b/kernel/signal.c index f05f4c4150d9..aee85bd76b8a 100644 --- a/kernel/signal.c +++ b/kernel/signal.c @@ -31,6 +31,7 @@ #include #include #include +#include #define CREATE_TRACE_POINTS #include @@ -3116,6 +3117,50 @@ int restore_altstack(const stack_t __user *uss) return err == -EFAULT ? err : 0; } +#ifdef CONFIG_COMPAT +#ifdef CONFIG_GENERIC_SIGALTSTACK +asmlinkage long compat_sys_sigaltstack(const compat_stack_t __user *uss_ptr, + compat_stack_t __user *uoss_ptr) +{ + stack_t uss, uoss; + int ret; + mm_segment_t seg; + + if (uss_ptr) { + compat_stack_t uss32; + + memset(&uss, 0, sizeof(stack_t)); + if (copy_from_user(&uss32, uss_ptr, sizeof(compat_stack_t))) + return -EFAULT; + uss.ss_sp = compat_ptr(uss32.ss_sp); + uss.ss_flags = uss32.ss_flags; + uss.ss_size = uss32.ss_size; + } + seg = get_fs(); + set_fs(KERNEL_DS); + ret = do_sigaltstack((stack_t __force __user *) (uss_ptr ? &uss : NULL), + (stack_t __force __user *) &uoss, + compat_user_stack_pointer()); + set_fs(seg); + if (ret >= 0 && uoss_ptr) { + if (!access_ok(VERIFY_WRITE, uoss_ptr, sizeof(compat_stack_t)) || + __put_user(ptr_to_compat(uoss.ss_sp), &uoss_ptr->ss_sp) || + __put_user(uoss.ss_flags, &uoss_ptr->ss_flags) || + __put_user(uoss.ss_size, &uoss_ptr->ss_size)) + ret = -EFAULT; + } + return ret; +} + +int compat_restore_altstack(const compat_stack_t __user *uss) +{ + int err = compat_sys_sigaltstack(uss, NULL); + /* squash all but -EFAULT for now */ + return err == -EFAULT ? err : 0; +} +#endif +#endif + #ifdef __ARCH_WANT_SYS_SIGPENDING /**