forked from ~ljy/RK356X_SDK_RELEASE

hc
2024-05-11 297b60346df8beafee954a0fd7c2d64f33f3b9bc
kernel/arch/x86/ia32/ia32_signal.c
....@@ -21,6 +21,7 @@
2121 #include <linux/personality.h>
2222 #include <linux/compat.h>
2323 #include <linux/binfmts.h>
24
+#include <linux/syscalls.h>
2425 #include <asm/ucontext.h>
2526 #include <linux/uaccess.h>
2627 #include <asm/fpu/internal.h>
....@@ -35,70 +36,56 @@
3536 #include <asm/sighandling.h>
3637 #include <asm/smap.h>
3738
39
+static inline void reload_segments(struct sigcontext_32 *sc)
40
+{
41
+ unsigned int cur;
42
+
43
+ savesegment(gs, cur);
44
+ if ((sc->gs | 0x03) != cur)
45
+ load_gs_index(sc->gs | 0x03);
46
+ savesegment(fs, cur);
47
+ if ((sc->fs | 0x03) != cur)
48
+ loadsegment(fs, sc->fs | 0x03);
49
+ savesegment(ds, cur);
50
+ if ((sc->ds | 0x03) != cur)
51
+ loadsegment(ds, sc->ds | 0x03);
52
+ savesegment(es, cur);
53
+ if ((sc->es | 0x03) != cur)
54
+ loadsegment(es, sc->es | 0x03);
55
+}
56
+
3857 /*
3958 * Do a signal return; undo the signal stack.
4059 */
41
-#define loadsegment_gs(v) load_gs_index(v)
42
-#define loadsegment_fs(v) loadsegment(fs, v)
43
-#define loadsegment_ds(v) loadsegment(ds, v)
44
-#define loadsegment_es(v) loadsegment(es, v)
45
-
46
-#define get_user_seg(seg) ({ unsigned int v; savesegment(seg, v); v; })
47
-#define set_user_seg(seg, v) loadsegment_##seg(v)
48
-
49
-#define COPY(x) { \
50
- get_user_ex(regs->x, &sc->x); \
51
-}
52
-
53
-#define GET_SEG(seg) ({ \
54
- unsigned short tmp; \
55
- get_user_ex(tmp, &sc->seg); \
56
- tmp; \
57
-})
58
-
59
-#define COPY_SEG_CPL3(seg) do { \
60
- regs->seg = GET_SEG(seg) | 3; \
61
-} while (0)
62
-
63
-#define RELOAD_SEG(seg) { \
64
- unsigned int pre = (seg) | 3; \
65
- unsigned int cur = get_user_seg(seg); \
66
- if (pre != cur) \
67
- set_user_seg(seg, pre); \
68
-}
69
-
7060 static int ia32_restore_sigcontext(struct pt_regs *regs,
71
- struct sigcontext_32 __user *sc)
61
+ struct sigcontext_32 __user *usc)
7262 {
73
- unsigned int tmpflags, err = 0;
74
- u16 gs, fs, es, ds;
75
- void __user *buf;
76
- u32 tmp;
63
+ struct sigcontext_32 sc;
7764
7865 /* Always make any pending restarted system calls return -EINTR */
7966 current->restart_block.fn = do_no_restart_syscall;
8067
81
- get_user_try {
82
- gs = GET_SEG(gs);
83
- fs = GET_SEG(fs);
84
- ds = GET_SEG(ds);
85
- es = GET_SEG(es);
68
+ if (unlikely(copy_from_user(&sc, usc, sizeof(sc))))
69
+ return -EFAULT;
8670
87
- COPY(di); COPY(si); COPY(bp); COPY(sp); COPY(bx);
88
- COPY(dx); COPY(cx); COPY(ip); COPY(ax);
89
- /* Don't touch extended registers */
71
+ /* Get only the ia32 registers. */
72
+ regs->bx = sc.bx;
73
+ regs->cx = sc.cx;
74
+ regs->dx = sc.dx;
75
+ regs->si = sc.si;
76
+ regs->di = sc.di;
77
+ regs->bp = sc.bp;
78
+ regs->ax = sc.ax;
79
+ regs->sp = sc.sp;
80
+ regs->ip = sc.ip;
9081
91
- COPY_SEG_CPL3(cs);
92
- COPY_SEG_CPL3(ss);
82
+ /* Get CS/SS and force CPL3 */
83
+ regs->cs = sc.cs | 0x03;
84
+ regs->ss = sc.ss | 0x03;
9385
94
- get_user_ex(tmpflags, &sc->flags);
95
- regs->flags = (regs->flags & ~FIX_EFLAGS) | (tmpflags & FIX_EFLAGS);
96
- /* disable syscall checks */
97
- regs->orig_ax = -1;
98
-
99
- get_user_ex(tmp, &sc->fpstate);
100
- buf = compat_ptr(tmp);
101
- } get_user_catch(err);
86
+ regs->flags = (regs->flags & ~FIX_EFLAGS) | (sc.flags & FIX_EFLAGS);
87
+ /* disable syscall checks */
88
+ regs->orig_ax = -1;
10289
10390 /*
10491 * Reload fs and gs if they have changed in the signal
....@@ -106,31 +93,20 @@
10693 * the handler, but does not clobber them at least in the
10794 * normal case.
10895 */
109
- RELOAD_SEG(gs);
110
- RELOAD_SEG(fs);
111
- RELOAD_SEG(ds);
112
- RELOAD_SEG(es);
113
-
114
- err |= fpu__restore_sig(buf, 1);
115
-
116
- force_iret();
117
-
118
- return err;
96
+ reload_segments(&sc);
97
+ return fpu__restore_sig(compat_ptr(sc.fpstate), 1);
11998 }
12099
121
-asmlinkage long sys32_sigreturn(const struct pt_regs *__unused)
100
+COMPAT_SYSCALL_DEFINE0(sigreturn)
122101 {
123102 struct pt_regs *regs = current_pt_regs();
124103 struct sigframe_ia32 __user *frame = (struct sigframe_ia32 __user *)(regs->sp-8);
125104 sigset_t set;
126105
127
- if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
106
+ if (!access_ok(frame, sizeof(*frame)))
128107 goto badframe;
129108 if (__get_user(set.sig[0], &frame->sc.oldmask)
130
- || (_COMPAT_NSIG_WORDS > 1
131
- && __copy_from_user((((char *) &set.sig) + 4),
132
- &frame->extramask,
133
- sizeof(frame->extramask))))
109
+ || __get_user(((__u32 *)&set)[1], &frame->extramask[0]))
134110 goto badframe;
135111
136112 set_current_blocked(&set);
....@@ -144,7 +120,7 @@
144120 return 0;
145121 }
146122
147
-asmlinkage long sys32_rt_sigreturn(const struct pt_regs *__unused)
123
+COMPAT_SYSCALL_DEFINE0(rt_sigreturn)
148124 {
149125 struct pt_regs *regs = current_pt_regs();
150126 struct rt_sigframe_ia32 __user *frame;
....@@ -152,9 +128,9 @@
152128
153129 frame = (struct rt_sigframe_ia32 __user *)(regs->sp - 4);
154130
155
- if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
131
+ if (!access_ok(frame, sizeof(*frame)))
156132 goto badframe;
157
- if (__copy_from_user(&set, &frame->uc.uc_sigmask, sizeof(set)))
133
+ if (__get_user(set.sig[0], (__u64 __user *)&frame->uc.uc_sigmask))
158134 goto badframe;
159135
160136 set_current_blocked(&set);
....@@ -176,43 +152,50 @@
176152 * Set up a signal frame.
177153 */
178154
179
-static int ia32_setup_sigcontext(struct sigcontext_32 __user *sc,
180
- void __user *fpstate,
181
- struct pt_regs *regs, unsigned int mask)
155
+#define get_user_seg(seg) ({ unsigned int v; savesegment(seg, v); v; })
156
+
157
+static __always_inline int
158
+__unsafe_setup_sigcontext32(struct sigcontext_32 __user *sc,
159
+ void __user *fpstate,
160
+ struct pt_regs *regs, unsigned int mask)
182161 {
183
- int err = 0;
162
+ unsafe_put_user(get_user_seg(gs), (unsigned int __user *)&sc->gs, Efault);
163
+ unsafe_put_user(get_user_seg(fs), (unsigned int __user *)&sc->fs, Efault);
164
+ unsafe_put_user(get_user_seg(ds), (unsigned int __user *)&sc->ds, Efault);
165
+ unsafe_put_user(get_user_seg(es), (unsigned int __user *)&sc->es, Efault);
184166
185
- put_user_try {
186
- put_user_ex(get_user_seg(gs), (unsigned int __user *)&sc->gs);
187
- put_user_ex(get_user_seg(fs), (unsigned int __user *)&sc->fs);
188
- put_user_ex(get_user_seg(ds), (unsigned int __user *)&sc->ds);
189
- put_user_ex(get_user_seg(es), (unsigned int __user *)&sc->es);
167
+ unsafe_put_user(regs->di, &sc->di, Efault);
168
+ unsafe_put_user(regs->si, &sc->si, Efault);
169
+ unsafe_put_user(regs->bp, &sc->bp, Efault);
170
+ unsafe_put_user(regs->sp, &sc->sp, Efault);
171
+ unsafe_put_user(regs->bx, &sc->bx, Efault);
172
+ unsafe_put_user(regs->dx, &sc->dx, Efault);
173
+ unsafe_put_user(regs->cx, &sc->cx, Efault);
174
+ unsafe_put_user(regs->ax, &sc->ax, Efault);
175
+ unsafe_put_user(current->thread.trap_nr, &sc->trapno, Efault);
176
+ unsafe_put_user(current->thread.error_code, &sc->err, Efault);
177
+ unsafe_put_user(regs->ip, &sc->ip, Efault);
178
+ unsafe_put_user(regs->cs, (unsigned int __user *)&sc->cs, Efault);
179
+ unsafe_put_user(regs->flags, &sc->flags, Efault);
180
+ unsafe_put_user(regs->sp, &sc->sp_at_signal, Efault);
181
+ unsafe_put_user(regs->ss, (unsigned int __user *)&sc->ss, Efault);
190182
191
- put_user_ex(regs->di, &sc->di);
192
- put_user_ex(regs->si, &sc->si);
193
- put_user_ex(regs->bp, &sc->bp);
194
- put_user_ex(regs->sp, &sc->sp);
195
- put_user_ex(regs->bx, &sc->bx);
196
- put_user_ex(regs->dx, &sc->dx);
197
- put_user_ex(regs->cx, &sc->cx);
198
- put_user_ex(regs->ax, &sc->ax);
199
- put_user_ex(current->thread.trap_nr, &sc->trapno);
200
- put_user_ex(current->thread.error_code, &sc->err);
201
- put_user_ex(regs->ip, &sc->ip);
202
- put_user_ex(regs->cs, (unsigned int __user *)&sc->cs);
203
- put_user_ex(regs->flags, &sc->flags);
204
- put_user_ex(regs->sp, &sc->sp_at_signal);
205
- put_user_ex(regs->ss, (unsigned int __user *)&sc->ss);
183
+ unsafe_put_user(ptr_to_compat(fpstate), &sc->fpstate, Efault);
206184
207
- put_user_ex(ptr_to_compat(fpstate), &sc->fpstate);
185
+ /* non-iBCS2 extensions.. */
186
+ unsafe_put_user(mask, &sc->oldmask, Efault);
187
+ unsafe_put_user(current->thread.cr2, &sc->cr2, Efault);
188
+ return 0;
208189
209
- /* non-iBCS2 extensions.. */
210
- put_user_ex(mask, &sc->oldmask);
211
- put_user_ex(current->thread.cr2, &sc->cr2);
212
- } put_user_catch(err);
213
-
214
- return err;
190
+Efault:
191
+ return -EFAULT;
215192 }
193
+
194
+#define unsafe_put_sigcontext32(sc, fp, regs, set, label) \
195
+do { \
196
+ if (__unsafe_setup_sigcontext32(sc, fp, regs, set->sig[0])) \
197
+ goto label; \
198
+} while(0)
216199
217200 /*
218201 * Determine which stack to use..
....@@ -221,8 +204,7 @@
221204 size_t frame_size,
222205 void __user **fpstate)
223206 {
224
- struct fpu *fpu = &current->thread.fpu;
225
- unsigned long sp;
207
+ unsigned long sp, fx_aligned, math_size;
226208
227209 /* Default to using normal stack */
228210 sp = regs->sp;
....@@ -236,15 +218,11 @@
236218 ksig->ka.sa.sa_restorer)
237219 sp = (unsigned long) ksig->ka.sa.sa_restorer;
238220
239
- if (fpu->initialized) {
240
- unsigned long fx_aligned, math_size;
241
-
242
- sp = fpu__alloc_mathframe(sp, 1, &fx_aligned, &math_size);
243
- *fpstate = (struct _fpstate_32 __user *) sp;
244
- if (copy_fpstate_to_sigframe(*fpstate, (void __user *)fx_aligned,
245
- math_size) < 0)
246
- return (void __user *) -1L;
247
- }
221
+ sp = fpu__alloc_mathframe(sp, 1, &fx_aligned, &math_size);
222
+ *fpstate = (struct _fpstate_32 __user *) sp;
223
+ if (copy_fpstate_to_sigframe(*fpstate, (void __user *)fx_aligned,
224
+ math_size) < 0)
225
+ return (void __user *) -1L;
248226
249227 sp -= frame_size;
250228 /* Align the stack pointer according to the i386 ABI,
....@@ -258,8 +236,7 @@
258236 {
259237 struct sigframe_ia32 __user *frame;
260238 void __user *restorer;
261
- int err = 0;
262
- void __user *fpstate = NULL;
239
+ void __user *fp = NULL;
263240
264241 /* copy_to_user optimizes that into a single 8 byte store */
265242 static const struct {
....@@ -272,22 +249,7 @@
272249 0x80cd, /* int $0x80 */
273250 };
274251
275
- frame = get_sigframe(ksig, regs, sizeof(*frame), &fpstate);
276
-
277
- if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
278
- return -EFAULT;
279
-
280
- if (__put_user(sig, &frame->sig))
281
- return -EFAULT;
282
-
283
- if (ia32_setup_sigcontext(&frame->sc, fpstate, regs, set->sig[0]))
284
- return -EFAULT;
285
-
286
- if (_COMPAT_NSIG_WORDS > 1) {
287
- if (__copy_to_user(frame->extramask, &set->sig[1],
288
- sizeof(frame->extramask)))
289
- return -EFAULT;
290
- }
252
+ frame = get_sigframe(ksig, regs, sizeof(*frame), &fp);
291253
292254 if (ksig->ka.sa.sa_flags & SA_RESTORER) {
293255 restorer = ksig->ka.sa.sa_restorer;
....@@ -300,18 +262,19 @@
300262 restorer = &frame->retcode;
301263 }
302264
303
- put_user_try {
304
- put_user_ex(ptr_to_compat(restorer), &frame->pretcode);
305
-
306
- /*
307
- * These are actually not used anymore, but left because some
308
- * gdb versions depend on them as a marker.
309
- */
310
- put_user_ex(*((u64 *)&code), (u64 __user *)frame->retcode);
311
- } put_user_catch(err);
312
-
313
- if (err)
265
+ if (!user_access_begin(frame, sizeof(*frame)))
314266 return -EFAULT;
267
+
268
+ unsafe_put_user(sig, &frame->sig, Efault);
269
+ unsafe_put_sigcontext32(&frame->sc, fp, regs, set, Efault);
270
+ unsafe_put_user(set->sig[1], &frame->extramask[0], Efault);
271
+ unsafe_put_user(ptr_to_compat(restorer), &frame->pretcode, Efault);
272
+ /*
273
+ * These are actually not used anymore, but left because some
274
+ * gdb versions depend on them as a marker.
275
+ */
276
+ unsafe_put_user(*((u64 *)&code), (u64 __user *)frame->retcode, Efault);
277
+ user_access_end();
315278
316279 /* Set up registers for signal handler */
317280 regs->sp = (unsigned long) frame;
....@@ -329,6 +292,9 @@
329292 regs->ss = __USER32_DS;
330293
331294 return 0;
295
+Efault:
296
+ user_access_end();
297
+ return -EFAULT;
332298 }
333299
334300 int ia32_setup_rt_frame(int sig, struct ksignal *ksig,
....@@ -336,10 +302,9 @@
336302 {
337303 struct rt_sigframe_ia32 __user *frame;
338304 void __user *restorer;
339
- int err = 0;
340
- void __user *fpstate = NULL;
305
+ void __user *fp = NULL;
341306
342
- /* __copy_to_user optimizes that into a single 8 byte store */
307
+ /* unsafe_put_user optimizes that into a single 8 byte store */
343308 static const struct {
344309 u8 movl;
345310 u32 val;
....@@ -352,44 +317,40 @@
352317 0,
353318 };
354319
355
- frame = get_sigframe(ksig, regs, sizeof(*frame), &fpstate);
320
+ frame = get_sigframe(ksig, regs, sizeof(*frame), &fp);
356321
357
- if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
322
+ if (!user_access_begin(frame, sizeof(*frame)))
358323 return -EFAULT;
359324
360
- put_user_try {
361
- put_user_ex(sig, &frame->sig);
362
- put_user_ex(ptr_to_compat(&frame->info), &frame->pinfo);
363
- put_user_ex(ptr_to_compat(&frame->uc), &frame->puc);
325
+ unsafe_put_user(sig, &frame->sig, Efault);
326
+ unsafe_put_user(ptr_to_compat(&frame->info), &frame->pinfo, Efault);
327
+ unsafe_put_user(ptr_to_compat(&frame->uc), &frame->puc, Efault);
364328
365
- /* Create the ucontext. */
366
- if (boot_cpu_has(X86_FEATURE_XSAVE))
367
- put_user_ex(UC_FP_XSTATE, &frame->uc.uc_flags);
368
- else
369
- put_user_ex(0, &frame->uc.uc_flags);
370
- put_user_ex(0, &frame->uc.uc_link);
371
- compat_save_altstack_ex(&frame->uc.uc_stack, regs->sp);
329
+ /* Create the ucontext. */
330
+ if (static_cpu_has(X86_FEATURE_XSAVE))
331
+ unsafe_put_user(UC_FP_XSTATE, &frame->uc.uc_flags, Efault);
332
+ else
333
+ unsafe_put_user(0, &frame->uc.uc_flags, Efault);
334
+ unsafe_put_user(0, &frame->uc.uc_link, Efault);
335
+ unsafe_compat_save_altstack(&frame->uc.uc_stack, regs->sp, Efault);
372336
373
- if (ksig->ka.sa.sa_flags & SA_RESTORER)
374
- restorer = ksig->ka.sa.sa_restorer;
375
- else
376
- restorer = current->mm->context.vdso +
377
- vdso_image_32.sym___kernel_rt_sigreturn;
378
- put_user_ex(ptr_to_compat(restorer), &frame->pretcode);
337
+ if (ksig->ka.sa.sa_flags & SA_RESTORER)
338
+ restorer = ksig->ka.sa.sa_restorer;
339
+ else
340
+ restorer = current->mm->context.vdso +
341
+ vdso_image_32.sym___kernel_rt_sigreturn;
342
+ unsafe_put_user(ptr_to_compat(restorer), &frame->pretcode, Efault);
379343
380
- /*
381
- * Not actually used anymore, but left because some gdb
382
- * versions need it.
383
- */
384
- put_user_ex(*((u64 *)&code), (u64 __user *)frame->retcode);
385
- } put_user_catch(err);
344
+ /*
345
+ * Not actually used anymore, but left because some gdb
346
+ * versions need it.
347
+ */
348
+ unsafe_put_user(*((u64 *)&code), (u64 __user *)frame->retcode, Efault);
349
+ unsafe_put_sigcontext32(&frame->uc.uc_mcontext, fp, regs, set, Efault);
350
+ unsafe_put_user(*(__u64 *)set, (__u64 *)&frame->uc.uc_sigmask, Efault);
351
+ user_access_end();
386352
387
- err |= __copy_siginfo_to_user32(&frame->info, &ksig->info, false);
388
- err |= ia32_setup_sigcontext(&frame->uc.uc_mcontext, fpstate,
389
- regs, set->sig[0]);
390
- err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set));
391
-
392
- if (err)
353
+ if (__copy_siginfo_to_user32(&frame->info, &ksig->info))
393354 return -EFAULT;
394355
395356 /* Set up registers for signal handler */
....@@ -408,4 +369,7 @@
408369 regs->ss = __USER32_DS;
409370
410371 return 0;
372
+Efault:
373
+ user_access_end();
374
+ return -EFAULT;
411375 }