From: Al Viro Date: Thu, 2 Aug 2012 19:05:11 +0000 (+0400) Subject: x86, um/x86: switch to generic sys_execve and kernel_execve X-Git-Tag: firefly_0821_release~3680^2~1868^2~5 X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=6783eaa2e1253fbcbe2c2f6bb4c843abf1343caf;p=firefly-linux-kernel-4.4.55.git x86, um/x86: switch to generic sys_execve and kernel_execve 32bit wrapper is lost on that; 64bit one is *not*, since we need to arrange for full pt_regs on stack when we call sys_execve() and we need to load callee-saved ones from there afterwards. Signed-off-by: Al Viro --- diff --git a/arch/um/kernel/exec.c b/arch/um/kernel/exec.c index 8c82786da823..e427301f55d6 100644 --- a/arch/um/kernel/exec.c +++ b/arch/um/kernel/exec.c @@ -16,7 +16,6 @@ #include "mem_user.h" #include "skas.h" #include "os.h" -#include "internal.h" void flush_thread(void) { @@ -49,27 +48,7 @@ void start_thread(struct pt_regs *regs, unsigned long eip, unsigned long esp) } EXPORT_SYMBOL(start_thread); -long um_execve(const char *file, const char __user *const __user *argv, const char __user *const __user *env) +void __noreturn ret_from_kernel_execve(struct pt_regs *unused) { - long err; - - err = do_execve(file, argv, env, ¤t->thread.regs); - if (!err) - UML_LONGJMP(current->thread.exec_buf, 1); - return err; -} - -long sys_execve(const char __user *file, const char __user *const __user *argv, - const char __user *const __user *env) -{ - long error; - char *filename; - - filename = getname(file); - error = PTR_ERR(filename); - if (IS_ERR(filename)) goto out; - error = do_execve(filename, argv, env, ¤t->thread.regs); - putname(filename); - out: - return error; + UML_LONGJMP(current->thread.exec_buf, 1); } diff --git a/arch/um/kernel/internal.h b/arch/um/kernel/internal.h deleted file mode 100644 index 5bf97db24a04..000000000000 --- a/arch/um/kernel/internal.h +++ /dev/null @@ -1 +0,0 @@ -extern long um_execve(const char *file, const char __user *const __user *argv, const char __user *const __user *env); diff --git a/arch/um/kernel/syscall.c b/arch/um/kernel/syscall.c index a4c6d8eee74c..a5639c472772 100644 --- a/arch/um/kernel/syscall.c +++ b/arch/um/kernel/syscall.c @@ -13,7 +13,6 @@ #include "asm/mman.h" #include "asm/uaccess.h" #include "asm/unistd.h" -#include "internal.h" long sys_fork(void) { @@ -50,19 +49,3 @@ long old_mmap(unsigned long addr, unsigned long len, out: return err; } - -int kernel_execve(const char *filename, - const char *const argv[], - const char *const envp[]) -{ - mm_segment_t fs; - int ret; - - fs = get_fs(); - set_fs(KERNEL_DS); - ret = um_execve(filename, (const char __user *const __user *)argv, - (const char __user *const __user *) envp); - set_fs(fs); - - return ret; -} diff --git a/arch/x86/ia32/ia32entry.S b/arch/x86/ia32/ia32entry.S index 20e5f7ba0e6b..e75f941bd2b2 100644 --- a/arch/x86/ia32/ia32entry.S +++ b/arch/x86/ia32/ia32entry.S @@ -459,7 +459,7 @@ 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, sys32_execve, %rcx + PTREGSCALL stub32_execve, compat_sys_execve, %rcx PTREGSCALL stub32_fork, sys_fork, %rdi PTREGSCALL stub32_clone, sys32_clone, %rdx PTREGSCALL stub32_vfork, sys_vfork, %rdi diff --git a/arch/x86/ia32/sys_ia32.c b/arch/x86/ia32/sys_ia32.c index 4540bece0946..6b31144589d0 100644 --- a/arch/x86/ia32/sys_ia32.c +++ b/arch/x86/ia32/sys_ia32.c @@ -385,21 +385,6 @@ asmlinkage long sys32_sendfile(int out_fd, int in_fd, return ret; } -asmlinkage long sys32_execve(const char __user *name, compat_uptr_t __user *argv, - compat_uptr_t __user *envp, struct pt_regs *regs) -{ - long error; - char *filename; - - filename = getname(name); - error = PTR_ERR(filename); - if (IS_ERR(filename)) - return error; - error = compat_do_execve(filename, argv, envp, regs); - putname(filename); - return error; -} - asmlinkage long sys32_clone(unsigned int clone_flags, unsigned int newsp, struct pt_regs *regs) { diff --git a/arch/x86/include/asm/sys_ia32.h b/arch/x86/include/asm/sys_ia32.h index 3fda9db48819..1ac127f41fe6 100644 --- a/arch/x86/include/asm/sys_ia32.h +++ b/arch/x86/include/asm/sys_ia32.h @@ -54,8 +54,6 @@ asmlinkage long sys32_pwrite(unsigned int, const char __user *, u32, u32, u32); asmlinkage long sys32_personality(unsigned long); asmlinkage long sys32_sendfile(int, int, compat_off_t __user *, s32); -asmlinkage long sys32_execve(const char __user *, compat_uptr_t __user *, - compat_uptr_t __user *, struct pt_regs *); asmlinkage long sys32_clone(unsigned int, unsigned int, struct pt_regs *); long sys32_lseek(unsigned int, int, unsigned int); diff --git a/arch/x86/include/asm/syscalls.h b/arch/x86/include/asm/syscalls.h index f1d8b441fc77..2be0b880417e 100644 --- a/arch/x86/include/asm/syscalls.h +++ b/arch/x86/include/asm/syscalls.h @@ -25,7 +25,7 @@ int sys_fork(struct pt_regs *); int sys_vfork(struct pt_regs *); long sys_execve(const char __user *, const char __user *const __user *, - const char __user *const __user *, struct pt_regs *); + const char __user *const __user *); long sys_clone(unsigned long, unsigned long, void __user *, void __user *, struct pt_regs *); diff --git a/arch/x86/include/asm/unistd.h b/arch/x86/include/asm/unistd.h index 0d9776e9e2dc..55d155560fdf 100644 --- a/arch/x86/include/asm/unistd.h +++ b/arch/x86/include/asm/unistd.h @@ -50,6 +50,8 @@ # define __ARCH_WANT_SYS_TIME # define __ARCH_WANT_SYS_UTIME # define __ARCH_WANT_SYS_WAITPID +# define __ARCH_WANT_SYS_EXECVE +# define __ARCH_WANT_KERNEL_EXECVE /* * "Conditional" syscalls diff --git a/arch/x86/kernel/Makefile b/arch/x86/kernel/Makefile index 8215e5652d97..566100002233 100644 --- a/arch/x86/kernel/Makefile +++ b/arch/x86/kernel/Makefile @@ -23,7 +23,7 @@ obj-y += time.o ioport.o ldt.o dumpstack.o nmi.o obj-y += setup.o x86_init.o i8259.o irqinit.o jump_label.o obj-$(CONFIG_IRQ_WORK) += irq_work.o obj-y += probe_roms.o -obj-$(CONFIG_X86_32) += sys_i386_32.o i386_ksyms_32.o +obj-$(CONFIG_X86_32) += i386_ksyms_32.o obj-$(CONFIG_X86_64) += sys_x86_64.o x8664_ksyms_64.o obj-y += syscall_$(BITS).o obj-$(CONFIG_X86_64) += vsyscall_64.o diff --git a/arch/x86/kernel/asm-offsets.c b/arch/x86/kernel/asm-offsets.c index 68de2dc962ec..28610822fb3c 100644 --- a/arch/x86/kernel/asm-offsets.c +++ b/arch/x86/kernel/asm-offsets.c @@ -69,4 +69,7 @@ void common(void) { OFFSET(BP_kernel_alignment, boot_params, hdr.kernel_alignment); OFFSET(BP_pref_address, boot_params, hdr.pref_address); OFFSET(BP_code32_start, boot_params, hdr.code32_start); + + BLANK(); + DEFINE(PTREGS_SIZE, sizeof(struct pt_regs)); } diff --git a/arch/x86/kernel/entry_32.S b/arch/x86/kernel/entry_32.S index ac1107346fc9..b6bb69239296 100644 --- a/arch/x86/kernel/entry_32.S +++ b/arch/x86/kernel/entry_32.S @@ -298,6 +298,13 @@ ENTRY(ret_from_fork) CFI_ENDPROC END(ret_from_fork) +ENTRY(ret_from_kernel_execve) + movl %eax, %esp + movl $0,PT_EAX(%esp) + GET_THREAD_INFO(%ebp) + jmp syscall_exit +END(ret_from_kernel_execve) + /* * Interrupt exit functions should be protected against kprobes */ @@ -322,8 +329,7 @@ ret_from_intr: andl $(X86_EFLAGS_VM | SEGMENT_RPL_MASK), %eax #else /* - * We can be coming here from a syscall done in the kernel space, - * e.g. a failed kernel_execve(). + * We can be coming here from child spawned by kernel_thread(). */ movl PT_CS(%esp), %eax andl $SEGMENT_RPL_MASK, %eax @@ -727,7 +733,6 @@ ENDPROC(ptregs_##name) PTREGSCALL1(iopl) PTREGSCALL0(fork) PTREGSCALL0(vfork) -PTREGSCALL3(execve) PTREGSCALL2(sigaltstack) PTREGSCALL0(sigreturn) PTREGSCALL0(rt_sigreturn) diff --git a/arch/x86/kernel/entry_64.S b/arch/x86/kernel/entry_64.S index 5526d17db676..053c9552ffd9 100644 --- a/arch/x86/kernel/entry_64.S +++ b/arch/x86/kernel/entry_64.S @@ -767,7 +767,6 @@ ENTRY(stub_execve) PARTIAL_FRAME 0 SAVE_REST FIXUP_TOP_OF_STACK %r11 - movq %rsp, %rcx call sys_execve RESTORE_TOP_OF_STACK %r11 movq %rax,RAX(%rsp) @@ -817,8 +816,7 @@ ENTRY(stub_x32_execve) PARTIAL_FRAME 0 SAVE_REST FIXUP_TOP_OF_STACK %r11 - movq %rsp, %rcx - call sys32_execve + call compat_sys_execve RESTORE_TOP_OF_STACK %r11 movq %rax,RAX(%rsp) RESTORE_REST @@ -1216,36 +1214,19 @@ bad_gs: jmp 2b .previous -/* - * execve(). This function needs to use IRET, not SYSRET, to set up all state properly. - * - * C extern interface: - * extern long execve(const char *name, char **argv, char **envp) - * - * asm input arguments: - * rdi: name, rsi: argv, rdx: envp - * - * We want to fallback into: - * extern long sys_execve(const char *name, char **argv,char **envp, struct pt_regs *regs) - * - * do_sys_execve asm fallback arguments: - * rdi: name, rsi: argv, rdx: envp, rcx: fake frame on the stack - */ -ENTRY(kernel_execve) - CFI_STARTPROC - FAKE_STACK_FRAME $0 - SAVE_ALL - movq %rsp,%rcx - call sys_execve - movq %rax, RAX(%rsp) - RESTORE_REST - testq %rax,%rax - je int_ret_from_sys_call - RESTORE_ARGS - UNFAKE_STACK_FRAME - ret - CFI_ENDPROC -END(kernel_execve) +ENTRY(ret_from_kernel_execve) + movq %rdi, %rsp + movl $0, RAX(%rsp) + // RESTORE_REST + movq 0*8(%rsp), %r15 + movq 1*8(%rsp), %r14 + movq 2*8(%rsp), %r13 + movq 3*8(%rsp), %r12 + movq 4*8(%rsp), %rbp + movq 5*8(%rsp), %rbx + addq $(6*8), %rsp + jmp int_ret_from_sys_call +END(ret_from_kernel_execve) /* Call softirq on interrupt stack. Interrupts are off. */ ENTRY(call_softirq) diff --git a/arch/x86/kernel/process.c b/arch/x86/kernel/process.c index 6947ec968bf8..eae2dd5cd5a0 100644 --- a/arch/x86/kernel/process.c +++ b/arch/x86/kernel/process.c @@ -298,25 +298,6 @@ sys_clone(unsigned long clone_flags, unsigned long newsp, return do_fork(clone_flags, newsp, regs, 0, parent_tid, child_tid); } -/* - * sys_execve() executes a new program. - */ -long sys_execve(const char __user *name, - const char __user *const __user *argv, - const char __user *const __user *envp, struct pt_regs *regs) -{ - long error; - char *filename; - - filename = getname(name); - error = PTR_ERR(filename); - if (IS_ERR(filename)) - return error; - error = do_execve(filename, argv, envp, regs); - putname(filename); - return error; -} - /* * Idle related variables and functions */ diff --git a/arch/x86/kernel/process_32.c b/arch/x86/kernel/process_32.c index c9939875d267..25e7e9390d26 100644 --- a/arch/x86/kernel/process_32.c +++ b/arch/x86/kernel/process_32.c @@ -207,6 +207,7 @@ start_thread(struct pt_regs *regs, unsigned long new_ip, unsigned long new_sp) regs->cs = __USER_CS; regs->ip = new_ip; regs->sp = new_sp; + regs->flags = X86_EFLAGS_IF; /* * Free the old FP and other extended state */ diff --git a/arch/x86/kernel/sys_i386_32.c b/arch/x86/kernel/sys_i386_32.c deleted file mode 100644 index 0b0cb5fede19..000000000000 --- a/arch/x86/kernel/sys_i386_32.c +++ /dev/null @@ -1,40 +0,0 @@ -/* - * This file contains various random system calls that - * have a non-standard calling sequence on the Linux/i386 - * platform. - */ - -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include - -#include -#include - -#include - -/* - * Do a system call from kernel instead of calling sys_execve so we - * end up with proper pt_regs. - */ -int kernel_execve(const char *filename, - const char *const argv[], - const char *const envp[]) -{ - long __res; - asm volatile ("int $0x80" - : "=a" (__res) - : "0" (__NR_execve), "b" (filename), "c" (argv), "d" (envp) : "memory"); - return __res; -} diff --git a/arch/x86/syscalls/syscall_32.tbl b/arch/x86/syscalls/syscall_32.tbl index 7a35a6e71d44..a47103fbc692 100644 --- a/arch/x86/syscalls/syscall_32.tbl +++ b/arch/x86/syscalls/syscall_32.tbl @@ -17,7 +17,7 @@ 8 i386 creat sys_creat 9 i386 link sys_link 10 i386 unlink sys_unlink -11 i386 execve ptregs_execve stub32_execve +11 i386 execve sys_execve stub32_execve 12 i386 chdir sys_chdir 13 i386 time sys_time compat_sys_time 14 i386 mknod sys_mknod diff --git a/arch/x86/um/sys_call_table_32.c b/arch/x86/um/sys_call_table_32.c index b5408cecac6c..232e60504b3a 100644 --- a/arch/x86/um/sys_call_table_32.c +++ b/arch/x86/um/sys_call_table_32.c @@ -25,7 +25,6 @@ #define old_mmap sys_old_mmap #define ptregs_fork sys_fork -#define ptregs_execve sys_execve #define ptregs_iopl sys_iopl #define ptregs_vm86old sys_vm86old #define ptregs_clone i386_clone