generic compat_sys_sigaltstack()

Again, conditional on CONFIG_GENERIC_SIGALTSTACK Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

generic compat_sys_sigaltstack()
Again, conditional on CONFIG_GENERIC_SIGALTSTACK Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Al Viro
1 parent 6bf9adfc90
Showing 10 changed files with 67 additions and 67 deletions Side-by-side Diff
arch/x86/ia32/ia32_signal.c
arch/x86/ia32/ia32entry.S
arch/x86/include/asm/ia32.h
arch/x86/include/asm/sys_ia32.h
arch/x86/kernel/entry_64.S
arch/x86/kernel/signal.c
arch/x86/syscalls/syscall_32.tbl
arch/x86/syscalls/syscall_64.tbl
include/linux/compat.h
kernel/signal.c
@@ -136,52 +136,6 @@
 	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 @@
 	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 @@
 	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;
@@ -464,7 +464,6 @@
  
 	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
@@ -29,16 +29,10 @@
 	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_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 */
@@ -69,8 +69,6 @@
  
 /* 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 *);
  
@@ -912,8 +912,6 @@
 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
@@ -857,7 +857,6 @@
 	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 @@
 	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;
@@ -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
@@ -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
@@ -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 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
  
@@ -31,6 +31,7 @@
 #include <linux/nsproxy.h>
 #include <linux/user_namespace.h>
 #include <linux/uprobes.h>
+#include <linux/compat.h>
 #define CREATE_TRACE_POINTS
 #include <trace/events/signal.h>
  
@@ -3115,6 +3116,50 @@
 	/* squash all but EFAULT for now */
 	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
...	...	@@ -136,52 +136,6 @@
136	136	return sigsuspend(&blocked);
137	137	}
138	138
139		-asmlinkage long sys32_sigaltstack(const stack_ia32_t __user *uss_ptr,
140		- stack_ia32_t __user *uoss_ptr,
141		- struct pt_regs *regs)
142		-{
143		- stack_t uss, uoss;
144		- int ret, err = 0;
145		- mm_segment_t seg;
146		-
147		- if (uss_ptr) {
148		- u32 ptr;
149		-
150		- memset(&uss, 0, sizeof(stack_t));
151		- if (!access_ok(VERIFY_READ, uss_ptr, sizeof(stack_ia32_t)))
152		- return -EFAULT;
153		-
154		- get_user_try {
155		- get_user_ex(ptr, &uss_ptr->ss_sp);
156		- get_user_ex(uss.ss_flags, &uss_ptr->ss_flags);
157		- get_user_ex(uss.ss_size, &uss_ptr->ss_size);
158		- } get_user_catch(err);
159		-
160		- if (err)
161		- return -EFAULT;
162		- uss.ss_sp = compat_ptr(ptr);
163		- }
164		- seg = get_fs();
165		- set_fs(KERNEL_DS);
166		- ret = do_sigaltstack((stack_t __force __user *) (uss_ptr ? &uss : NULL),
167		- (stack_t __force __user *) &uoss, regs->sp);
168		- set_fs(seg);
169		- if (ret >= 0 && uoss_ptr) {
170		- if (!access_ok(VERIFY_WRITE, uoss_ptr, sizeof(stack_ia32_t)))
171		- return -EFAULT;
172		-
173		- put_user_try {
174		- put_user_ex(ptr_to_compat(uoss.ss_sp), &uoss_ptr->ss_sp);
175		- put_user_ex(uoss.ss_flags, &uoss_ptr->ss_flags);
176		- put_user_ex(uoss.ss_size, &uoss_ptr->ss_size);
177		- } put_user_catch(err);
178		-
179		- if (err)
180		- ret = -EFAULT;
181		- }
182		- return ret;
183		-}
184		-
185	139	/*
186	140	* Do a signal return; undo the signal stack.
187	141	*/
...	...	@@ -292,7 +246,6 @@
292	246	struct rt_sigframe_ia32 __user *frame;
293	247	sigset_t set;
294	248	unsigned int ax;
295		- struct pt_regs tregs;
296	249
297	250	frame = (struct rt_sigframe_ia32 __user *)(regs->sp - 4);
298	251
...	...	@@ -306,8 +259,7 @@
306	259	if (ia32_restore_sigcontext(regs, &frame->uc.uc_mcontext, &ax))
307	260	goto badframe;
308	261
309		- tregs = *regs;
310		- if (sys32_sigaltstack(&frame->uc.uc_stack, NULL, &tregs) == -EFAULT)
	262	+ if (compat_restore_altstack(&frame->uc.uc_stack))
311	263	goto badframe;
312	264
313	265	return ax;
...	...	@@ -464,7 +464,6 @@
464	464
465	465	PTREGSCALL stub32_rt_sigreturn, sys32_rt_sigreturn, %rdi
466	466	PTREGSCALL stub32_sigreturn, sys32_sigreturn, %rdi
467		- PTREGSCALL stub32_sigaltstack, sys32_sigaltstack, %rdx
468	467	PTREGSCALL stub32_execve, compat_sys_execve, %rcx
469	468	PTREGSCALL stub32_fork, sys_fork, %rdi
470	469	PTREGSCALL stub32_vfork, sys_vfork, %rdi
...	...	@@ -29,16 +29,10 @@
29	29	unsigned int sa_restorer; /* Another 32 bit pointer */
30	30	};
31	31
32		-typedef struct sigaltstack_ia32 {
33		- unsigned int ss_sp;
34		- int ss_flags;
35		- unsigned int ss_size;
36		-} stack_ia32_t;
37		-
38	32	struct ucontext_ia32 {
39	33	unsigned int uc_flags;
40	34	unsigned int uc_link;
41		- stack_ia32_t uc_stack;
	35	+ compat_stack_t uc_stack;
42	36	struct sigcontext_ia32 uc_mcontext;
43	37	compat_sigset_t uc_sigmask; /* mask last for extensibility */
44	38	};
...	...	@@ -46,7 +40,7 @@
46	40	struct ucontext_x32 {
47	41	unsigned int uc_flags;
48	42	unsigned int uc_link;
49		- stack_ia32_t uc_stack;
	43	+ compat_stack_t uc_stack;
50	44	unsigned int uc__pad0; /* needed for alignment */
51	45	struct sigcontext uc_mcontext; /* the 64-bit sigcontext type */
52	46	compat_sigset_t uc_sigmask; /* mask last for extensibility */
...	...	@@ -69,8 +69,6 @@
69	69
70	70	/* ia32/ia32_signal.c */
71	71	asmlinkage long sys32_sigsuspend(int, int, old_sigset_t);
72		-asmlinkage long sys32_sigaltstack(const stack_ia32_t __user *,
73		- stack_ia32_t __user , struct pt_regs );
74	72	asmlinkage long sys32_sigreturn(struct pt_regs *);
75	73	asmlinkage long sys32_rt_sigreturn(struct pt_regs *);
76	74
...	...	@@ -912,8 +912,6 @@
912	912	END(stub_rt_sigreturn)
913	913
914	914	#ifdef CONFIG_X86_X32_ABI
915		- PTREGSCALL stub_x32_sigaltstack, sys32_sigaltstack, %rdx
916		-
917	915	ENTRY(stub_x32_rt_sigreturn)
918	916	CFI_STARTPROC
919	917	addq $8, %rsp
...	...	@@ -857,7 +857,6 @@
857	857	struct rt_sigframe_x32 __user *frame;
858	858	sigset_t set;
859	859	unsigned long ax;
860		- struct pt_regs tregs;
861	860
862	861	frame = (struct rt_sigframe_x32 __user *)(regs->sp - 8);
863	862
...	...	@@ -871,8 +870,7 @@
871	870	if (restore_sigcontext(regs, &frame->uc.uc_mcontext, &ax))
872	871	goto badframe;
873	872
874		- tregs = *regs;
875		- if (sys32_sigaltstack(&frame->uc.uc_stack, NULL, &tregs) == -EFAULT)
	873	+ if (compat_restore_altstack(&frame->uc.uc_stack))
876	874	goto badframe;
877	875
878	876	return ax;
...	...	@@ -192,7 +192,7 @@
192	192	183 i386 getcwd sys_getcwd
193	193	184 i386 capget sys_capget
194	194	185 i386 capset sys_capset
195		-186 i386 sigaltstack sys_sigaltstack stub32_sigaltstack
	195	+186 i386 sigaltstack sys_sigaltstack compat_sys_sigaltstack
196	196	187 i386 sendfile sys_sendfile sys32_sendfile
197	197	188 i386 getpmsg
198	198	189 i386 putpmsg
...	...	@@ -337,7 +337,7 @@
337	337	522 x32 rt_sigpending sys32_rt_sigpending
338	338	523 x32 rt_sigtimedwait compat_sys_rt_sigtimedwait
339	339	524 x32 rt_sigqueueinfo sys32_rt_sigqueueinfo
340		-525 x32 sigaltstack stub_x32_sigaltstack
	340	+525 x32 sigaltstack compat_sys_sigaltstack
341	341	526 x32 timer_create compat_sys_timer_create
342	342	527 x32 mq_notify compat_sys_mq_notify
343	343	528 x32 kexec_load compat_sys_kexec_load
...	...	@@ -68,6 +68,16 @@
68	68	#ifndef compat_user_stack_pointer
69	69	#define compat_user_stack_pointer() current_user_stack_pointer()
70	70	#endif
	71	+#ifdef CONFIG_GENERIC_SIGALTSTACK
	72	+#ifndef compat_sigaltstack /* we'll need that for MIPS */
	73	+typedef struct compat_sigaltstack {
	74	+ compat_uptr_t ss_sp;
	75	+ int ss_flags;
	76	+ compat_size_t ss_size;
	77	+} compat_stack_t;
	78	+#endif
	79	+#endif
	80	+
71	81	#define compat_jiffies_to_clock_t(x) \
72	82	(((unsigned long)(x) * COMPAT_USER_HZ) / HZ)
73	83
...	...	@@ -632,6 +642,12 @@
632	642
633	643	asmlinkage long compat_sys_sendfile(int out_fd, int in_fd,
634	644	compat_off_t __user *offset, compat_size_t count);
	645	+#ifdef CONFIG_GENERIC_SIGALTSTACK
	646	+asmlinkage long compat_sys_sigaltstack(const compat_stack_t __user *uss_ptr,
	647	+ compat_stack_t __user *uoss_ptr);
	648	+
	649	+int compat_restore_altstack(const compat_stack_t __user *uss);
	650	+#endif
635	651
636	652	#else
637	653
...	...	@@ -31,6 +31,7 @@
31	31	#include <linux/nsproxy.h>
32	32	#include <linux/user_namespace.h>
33	33	#include <linux/uprobes.h>
	34	+#include <linux/compat.h>
34	35	#define CREATE_TRACE_POINTS
35	36	#include <trace/events/signal.h>
36	37
...	...	@@ -3115,6 +3116,50 @@
3115	3116	/* squash all but EFAULT for now */
3116	3117	return err == -EFAULT ? err : 0;
3117	3118	}
	3119	+
	3120	+#ifdef CONFIG_COMPAT
	3121	+#ifdef CONFIG_GENERIC_SIGALTSTACK
	3122	+asmlinkage long compat_sys_sigaltstack(const compat_stack_t __user *uss_ptr,
	3123	+ compat_stack_t __user *uoss_ptr)
	3124	+{
	3125	+ stack_t uss, uoss;
	3126	+ int ret;
	3127	+ mm_segment_t seg;
	3128	+
	3129	+ if (uss_ptr) {
	3130	+ compat_stack_t uss32;
	3131	+
	3132	+ memset(&uss, 0, sizeof(stack_t));
	3133	+ if (copy_from_user(&uss32, uss_ptr, sizeof(compat_stack_t)))
	3134	+ return -EFAULT;
	3135	+ uss.ss_sp = compat_ptr(uss32.ss_sp);
	3136	+ uss.ss_flags = uss32.ss_flags;
	3137	+ uss.ss_size = uss32.ss_size;
	3138	+ }
	3139	+ seg = get_fs();
	3140	+ set_fs(KERNEL_DS);
	3141	+ ret = do_sigaltstack((stack_t __force __user *) (uss_ptr ? &uss : NULL),
	3142	+ (stack_t __force __user *) &uoss,
	3143	+ compat_user_stack_pointer());
	3144	+ set_fs(seg);
	3145	+ if (ret >= 0 && uoss_ptr) {
	3146	+ if (!access_ok(VERIFY_WRITE, uoss_ptr, sizeof(compat_stack_t)) \|\|
	3147	+ __put_user(ptr_to_compat(uoss.ss_sp), &uoss_ptr->ss_sp) \|\|
	3148	+ __put_user(uoss.ss_flags, &uoss_ptr->ss_flags) \|\|
	3149	+ __put_user(uoss.ss_size, &uoss_ptr->ss_size))
	3150	+ ret = -EFAULT;
	3151	+ }
	3152	+ return ret;
	3153	+}
	3154	+
	3155	+int compat_restore_altstack(const compat_stack_t __user *uss)
	3156	+{
	3157	+ int err = compat_sys_sigaltstack(uss, NULL);
	3158	+ /* squash all but -EFAULT for now */
	3159	+ return err == -EFAULT ? err : 0;
	3160	+}
	3161	+#endif
	3162	+#endif
3118	3163
3119	3164	#ifdef __ARCH_WANT_SYS_SIGPENDING
3120	3165