Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/uml
Pull UML fixes from Richard Weinberger:
"Special thanks goes to Toralf Föster for continuously testing UML and
reporting issues!"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/uml:
um: remove dead code
um: siginfo cleanup
uml: Fix which_tmpdir failure when /dev/shm is a symlink, and in other edge cases
um: Fix wait_stub_done() error handling
um: Mark stub pages mapping with VM_PFNMAP
um: Fix return value of strnlen_user()
+213
-61
+2
-2
arch/um/kernel/signal.c
+2
-2
arch/um/kernel/signal.c
···
19
19
* OK, we're invoking a handler
20
20
*/
21
21
static void handle_signal(struct pt_regs *regs, unsigned long signr,
22
-
struct k_sigaction *ka, siginfo_t *info)
22
+
struct k_sigaction *ka, struct siginfo *info)
23
23
{
24
24
sigset_t *oldset = sigmask_to_save();
25
25
int singlestep = 0;
···
71
71
static int kern_do_signal(struct pt_regs *regs)
72
72
{
73
73
struct k_sigaction ka_copy;
74
-
siginfo_t info;
74
+
struct siginfo info;
75
75
int sig, handled_sig = 0;
76
76
77
77
while ((sig = get_signal_to_deliver(&info, &ka_copy, regs, NULL)) > 0) {
+1
-1
arch/um/kernel/skas/mmu.c
+1
-1
arch/um/kernel/skas/mmu.c
···
123
123
/* dup_mmap already holds mmap_sem */
124
124
err = install_special_mapping(mm, STUB_START, STUB_END - STUB_START,
125
125
VM_READ | VM_MAYREAD | VM_EXEC |
126
-
VM_MAYEXEC | VM_DONTCOPY,
126
+
VM_MAYEXEC | VM_DONTCOPY | VM_PFNMAP,
127
127
mm->context.stub_pages);
128
128
if (err) {
129
129
printk(KERN_ERR "install_special_mapping returned %d\n", err);
+1
-1
arch/um/kernel/skas/uaccess.c
+1
-1
arch/um/kernel/skas/uaccess.c
+189
-41
arch/um/os-Linux/mem.c
+189
-41
arch/um/os-Linux/mem.c
···
53
53
}
54
54
55
55
/*
56
+
* Remove bytes from the front of the buffer and refill it so that if there's a
57
+
* partial string that we care about, it will be completed, and we can recognize
58
+
* it.
59
+
*/
60
+
static int pop(int fd, char *buf, size_t size, size_t npop)
61
+
{
62
+
ssize_t n;
63
+
size_t len = strlen(&buf[npop]);
64
+
65
+
memmove(buf, &buf[npop], len + 1);
66
+
n = read(fd, &buf[len], size - len - 1);
67
+
if (n < 0)
68
+
return -errno;
69
+
70
+
buf[len + n] = '\0';
71
+
return 1;
72
+
}
73
+
74
+
/*
56
75
* This will return 1, with the first character in buf being the
57
76
* character following the next instance of c in the file. This will
58
77
* read the file as needed. If there's an error, -errno is returned;
···
80
61
static int next(int fd, char *buf, size_t size, char c)
81
62
{
82
63
ssize_t n;
83
-
size_t len;
84
64
char *ptr;
85
65
86
66
while ((ptr = strchr(buf, c)) == NULL) {
···
92
74
buf[n] = '\0';
93
75
}
94
76
95
-
ptr++;
96
-
len = strlen(ptr);
97
-
memmove(buf, ptr, len + 1);
77
+
return pop(fd, buf, size, ptr - buf + 1);
78
+
}
79
+
80
+
/*
81
+
* Decode an octal-escaped and space-terminated path of the form used by
82
+
* /proc/mounts. May be used to decode a path in-place. "out" must be at least
83
+
* as large as the input. The output is always null-terminated. "len" gets the
84
+
* length of the output, excluding the trailing null. Returns 0 if a full path
85
+
* was successfully decoded, otherwise an error.
86
+
*/
87
+
static int decode_path(const char *in, char *out, size_t *len)
88
+
{
89
+
char *first = out;
90
+
int c;
91
+
int i;
92
+
int ret = -EINVAL;
93
+
while (1) {
94
+
switch (*in) {
95
+
case '\0':
96
+
goto out;
97
+
98
+
case ' ':
99
+
ret = 0;
100
+
goto out;
101
+
102
+
case '\\':
103
+
in++;
104
+
c = 0;
105
+
for (i = 0; i < 3; i++) {
106
+
if (*in < '0' || *in > '7')
107
+
goto out;
108
+
c = (c << 3) | (*in++ - '0');
109
+
}
110
+
*(unsigned char *)out++ = (unsigned char) c;
111
+
break;
112
+
113
+
default:
114
+
*out++ = *in++;
115
+
break;
116
+
}
117
+
}
118
+
119
+
out:
120
+
*out = '\0';
121
+
*len = out - first;
122
+
return ret;
123
+
}
124
+
125
+
/*
126
+
* Computes the length of s when encoded with three-digit octal escape sequences
127
+
* for the characters in chars.
128
+
*/
129
+
static size_t octal_encoded_length(const char *s, const char *chars)
130
+
{
131
+
size_t len = strlen(s);
132
+
while ((s = strpbrk(s, chars)) != NULL) {
133
+
len += 3;
134
+
s++;
135
+
}
136
+
137
+
return len;
138
+
}
139
+
140
+
enum {
141
+
OUTCOME_NOTHING_MOUNTED,
142
+
OUTCOME_TMPFS_MOUNT,
143
+
OUTCOME_NON_TMPFS_MOUNT,
144
+
};
145
+
146
+
/* Read a line of /proc/mounts data looking for a tmpfs mount at "path". */
147
+
static int read_mount(int fd, char *buf, size_t bufsize, const char *path,
148
+
int *outcome)
149
+
{
150
+
int found;
151
+
int match;
152
+
char *space;
153
+
size_t len;
154
+
155
+
enum {
156
+
MATCH_NONE,
157
+
MATCH_EXACT,
158
+
MATCH_PARENT,
159
+
};
160
+
161
+
found = next(fd, buf, bufsize, ' ');
162
+
if (found != 1)
163
+
return found;
98
164
99
165
/*
100
-
* Refill the buffer so that if there's a partial string that we care
101
-
* about, it will be completed, and we can recognize it.
166
+
* If there's no following space in the buffer, then this path is
167
+
* truncated, so it can't be the one we're looking for.
102
168
*/
103
-
n = read(fd, &buf[len], size - len - 1);
104
-
if (n < 0)
105
-
return -errno;
169
+
space = strchr(buf, ' ');
170
+
if (space) {
171
+
match = MATCH_NONE;
172
+
if (!decode_path(buf, buf, &len)) {
173
+
if (!strcmp(buf, path))
174
+
match = MATCH_EXACT;
175
+
else if (!strncmp(buf, path, len)
176
+
&& (path[len] == '/' || !strcmp(buf, "/")))
177
+
match = MATCH_PARENT;
178
+
}
106
179
107
-
buf[len + n] = '\0';
108
-
return 1;
180
+
found = pop(fd, buf, bufsize, space - buf + 1);
181
+
if (found != 1)
182
+
return found;
183
+
184
+
switch (match) {
185
+
case MATCH_EXACT:
186
+
if (!strncmp(buf, "tmpfs", strlen("tmpfs")))
187
+
*outcome = OUTCOME_TMPFS_MOUNT;
188
+
else
189
+
*outcome = OUTCOME_NON_TMPFS_MOUNT;
190
+
break;
191
+
192
+
case MATCH_PARENT:
193
+
/* This mount obscures any previous ones. */
194
+
*outcome = OUTCOME_NOTHING_MOUNTED;
195
+
break;
196
+
}
197
+
}
198
+
199
+
return next(fd, buf, bufsize, '\n');
109
200
}
110
201
111
202
/* which_tmpdir is called only during early boot */
···
233
106
*/
234
107
static void which_tmpdir(void)
235
108
{
236
-
int fd, found;
237
-
char buf[128] = { '\0' };
109
+
int fd;
110
+
int found;
111
+
int outcome;
112
+
char *path;
113
+
char *buf;
114
+
size_t bufsize;
238
115
239
116
if (checked_tmpdir)
240
117
return;
···
247
116
248
117
printf("Checking for tmpfs mount on /dev/shm...");
249
118
119
+
path = realpath("/dev/shm", NULL);
120
+
if (!path) {
121
+
printf("failed to check real path, errno = %d\n", errno);
122
+
return;
123
+
}
124
+
printf("%s...", path);
125
+
126
+
/*
127
+
* The buffer needs to be able to fit the full octal-escaped path, a
128
+
* space, and a trailing null in order to successfully decode it.
129
+
*/
130
+
bufsize = octal_encoded_length(path, " \t\n\\") + 2;
131
+
132
+
if (bufsize < 128)
133
+
bufsize = 128;
134
+
135
+
buf = malloc(bufsize);
136
+
if (!buf) {
137
+
printf("malloc failed, errno = %d\n", errno);
138
+
goto out;
139
+
}
140
+
buf[0] = '\0';
141
+
250
142
fd = open("/proc/mounts", O_RDONLY);
251
143
if (fd < 0) {
252
144
printf("failed to open /proc/mounts, errno = %d\n", errno);
253
-
return;
145
+
goto out1;
254
146
}
255
147
148
+
outcome = OUTCOME_NOTHING_MOUNTED;
256
149
while (1) {
257
-
found = next(fd, buf, ARRAY_SIZE(buf), ' ');
258
-
if (found != 1)
259
-
break;
260
-
261
-
if (!strncmp(buf, "/dev/shm", strlen("/dev/shm")))
262
-
goto found;
263
-
264
-
found = next(fd, buf, ARRAY_SIZE(buf), '\n');
150
+
found = read_mount(fd, buf, bufsize, path, &outcome);
265
151
if (found != 1)
266
152
break;
267
153
}
268
154
269
-
err:
270
-
if (found == 0)
271
-
printf("nothing mounted on /dev/shm\n");
272
-
else if (found < 0)
155
+
if (found < 0) {
273
156
printf("read returned errno %d\n", -found);
157
+
} else {
158
+
switch (outcome) {
159
+
case OUTCOME_TMPFS_MOUNT:
160
+
printf("OK\n");
161
+
default_tmpdir = "/dev/shm";
162
+
break;
274
163
275
-
out:
276
-
close(fd);
164
+
case OUTCOME_NON_TMPFS_MOUNT:
165
+
printf("not tmpfs\n");
166
+
break;
277
167
278
-
return;
279
-
280
-
found:
281
-
found = next(fd, buf, ARRAY_SIZE(buf), ' ');
282
-
if (found != 1)
283
-
goto err;
284
-
285
-
if (strncmp(buf, "tmpfs", strlen("tmpfs"))) {
286
-
printf("not tmpfs\n");
287
-
goto out;
168
+
default:
169
+
printf("nothing mounted on /dev/shm\n");
170
+
break;
171
+
}
288
172
}
289
173
290
-
printf("OK\n");
291
-
default_tmpdir = "/dev/shm";
292
-
goto out;
174
+
close(fd);
175
+
out1:
176
+
free(buf);
177
+
out:
178
+
free(path);
293
179
}
294
180
295
181
static int __init make_tempfile(const char *template, char **out_tempname,
+4
-4
arch/um/os-Linux/signal.c
+4
-4
arch/um/os-Linux/signal.c
···
25
25
[SIGIO] = sigio_handler,
26
26
[SIGVTALRM] = timer_handler };
27
27
28
-
static void sig_handler_common(int sig, siginfo_t *si, mcontext_t *mc)
28
+
static void sig_handler_common(int sig, struct siginfo *si, mcontext_t *mc)
29
29
{
30
30
struct uml_pt_regs r;
31
31
int save_errno = errno;
···
61
61
static int signals_enabled;
62
62
static unsigned int signals_pending;
63
63
64
-
void sig_handler(int sig, siginfo_t *si, mcontext_t *mc)
64
+
void sig_handler(int sig, struct siginfo *si, mcontext_t *mc)
65
65
{
66
66
int enabled;
67
67
···
120
120
panic("enabling signal stack failed, errno = %d\n", errno);
121
121
}
122
122
123
-
static void (*handlers[_NSIG])(int sig, siginfo_t *si, mcontext_t *mc) = {
123
+
static void (*handlers[_NSIG])(int sig, struct siginfo *si, mcontext_t *mc) = {
124
124
[SIGSEGV] = sig_handler,
125
125
[SIGBUS] = sig_handler,
126
126
[SIGILL] = sig_handler,
···
162
162
while ((sig = ffs(pending)) != 0){
163
163
sig--;
164
164
pending &= ~(1 << sig);
165
-
(*handlers[sig])(sig, si, mc);
165
+
(*handlers[sig])(sig, (struct siginfo *)si, mc);
166
166
}
167
167
168
168
/*
+12
-7
arch/um/os-Linux/skas/process.c
+12
-7
arch/um/os-Linux/skas/process.c
···
54
54
55
55
void wait_stub_done(int pid)
56
56
{
57
-
int n, status, err;
57
+
int n, status, err, bad_stop = 0;
58
58
59
59
while (1) {
60
60
CATCH_EINTR(n = waitpid(pid, &status, WUNTRACED | __WALL));
···
74
74
75
75
if (((1 << WSTOPSIG(status)) & STUB_DONE_MASK) != 0)
76
76
return;
77
+
else
78
+
bad_stop = 1;
77
79
78
80
bad_wait:
79
81
err = ptrace_dump_regs(pid);
···
85
83
printk(UM_KERN_ERR "wait_stub_done : failed to wait for SIGTRAP, "
86
84
"pid = %d, n = %d, errno = %d, status = 0x%x\n", pid, n, errno,
87
85
status);
88
-
fatal_sigsegv();
86
+
if (bad_stop)
87
+
kill(pid, SIGKILL);
88
+
else
89
+
fatal_sigsegv();
89
90
}
90
91
91
92
extern unsigned long current_stub_stack(void);
···
414
409
if (WIFSTOPPED(status)) {
415
410
int sig = WSTOPSIG(status);
416
411
417
-
ptrace(PTRACE_GETSIGINFO, pid, 0, &si);
412
+
ptrace(PTRACE_GETSIGINFO, pid, 0, (struct siginfo *)&si);
418
413
419
414
switch (sig) {
420
415
case SIGSEGV:
···
422
417
!ptrace_faultinfo) {
423
418
get_skas_faultinfo(pid,
424
419
®s->faultinfo);
425
-
(*sig_info[SIGSEGV])(SIGSEGV, &si,
420
+
(*sig_info[SIGSEGV])(SIGSEGV, (struct siginfo *)&si,
426
421
regs);
427
422
}
428
423
else handle_segv(pid, regs);
···
431
426
handle_trap(pid, regs, local_using_sysemu);
432
427
break;
433
428
case SIGTRAP:
434
-
relay_signal(SIGTRAP, &si, regs);
429
+
relay_signal(SIGTRAP, (struct siginfo *)&si, regs);
435
430
break;
436
431
case SIGVTALRM:
437
432
now = os_nsecs();
438
433
if (now < nsecs)
439
434
break;
440
435
block_signals();
441
-
(*sig_info[sig])(sig, &si, regs);
436
+
(*sig_info[sig])(sig, (struct siginfo *)&si, regs);
442
437
unblock_signals();
443
438
nsecs = timer.it_value.tv_sec *
444
439
UM_NSEC_PER_SEC +
···
452
447
case SIGFPE:
453
448
case SIGWINCH:
454
449
block_signals();
455
-
(*sig_info[sig])(sig, &si, regs);
450
+
(*sig_info[sig])(sig, (struct siginfo *)&si, regs);
456
451
unblock_signals();
457
452
break;
458
453
default: