summaryrefslogtreecommitdiff
path: root/arch/x86/kernel
diff options
context:
space:
mode:
authorAl Viro <viro@zeniv.linux.org.uk>2012-08-02 23:05:11 +0400
committerAl Viro <viro@zeniv.linux.org.uk>2012-09-30 22:53:32 -0400
commit6783eaa2e1253fbcbe2c2f6bb4c843abf1343caf (patch)
tree457e7b1d54396ed31ba92b7fe7024723d26ba565 /arch/x86/kernel
parent7076aada1040de4ed79a5977dbabdb5e5ea5e249 (diff)
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 <viro@zeniv.linux.org.uk>
Diffstat (limited to 'arch/x86/kernel')
-rw-r--r--arch/x86/kernel/Makefile2
-rw-r--r--arch/x86/kernel/asm-offsets.c3
-rw-r--r--arch/x86/kernel/entry_32.S11
-rw-r--r--arch/x86/kernel/entry_64.S47
-rw-r--r--arch/x86/kernel/process.c19
-rw-r--r--arch/x86/kernel/process_32.c1
-rw-r--r--arch/x86/kernel/sys_i386_32.c40
7 files changed, 27 insertions, 96 deletions
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
@@ -299,25 +299,6 @@ sys_clone(unsigned long clone_flags, unsigned long newsp,
}
/*
- * 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
*/
unsigned long boot_option_idle_override = IDLE_NO_OVERRIDE;
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 <linux/errno.h>
-#include <linux/sched.h>
-#include <linux/mm.h>
-#include <linux/fs.h>
-#include <linux/smp.h>
-#include <linux/sem.h>
-#include <linux/msg.h>
-#include <linux/shm.h>
-#include <linux/stat.h>
-#include <linux/syscalls.h>
-#include <linux/mman.h>
-#include <linux/file.h>
-#include <linux/utsname.h>
-#include <linux/ipc.h>
-
-#include <linux/uaccess.h>
-#include <linux/unistd.h>
-
-#include <asm/syscalls.h>
-
-/*
- * 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;
-}