1 /*
2  * Copyright (C) 2019 The Android Open Source Project
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 #define ATRACE_TAG ATRACE_TAG_DALVIK
18 
19 #include "palette/palette.h"
20 
21 #include <errno.h>
22 #include <sys/resource.h>
23 #include <sys/time.h>
24 #include <unistd.h>
25 
26 #include <filesystem>
27 #include <mutex>
28 
29 #include <android-base/file.h>
30 #include <android-base/logging.h>
31 #include <android-base/macros.h>
32 #include <cutils/ashmem.h>
33 #include <cutils/trace.h>
34 #include <processgroup/processgroup.h>
35 #include <processgroup/sched_policy.h>
36 #include <selinux/selinux.h>
37 #include <tombstoned/tombstoned.h>
38 #include <utils/Thread.h>
39 
40 #include "palette_system.h"
41 
42 // Conversion map for "nice" values.
43 //
44 // We use Android thread priority constants to be consistent with the rest
45 // of the system.  In some cases adjacent entries may overlap.
46 //
47 static const int kNiceValues[art::palette::kNumManagedThreadPriorities] = {
48         ANDROID_PRIORITY_LOWEST,  // 1 (MIN_PRIORITY)
49         ANDROID_PRIORITY_BACKGROUND + 6,
50         ANDROID_PRIORITY_BACKGROUND + 3,
51         ANDROID_PRIORITY_BACKGROUND,
52         ANDROID_PRIORITY_NORMAL,  // 5 (NORM_PRIORITY)
53         ANDROID_PRIORITY_NORMAL - 2,
54         ANDROID_PRIORITY_NORMAL - 4,
55         ANDROID_PRIORITY_URGENT_DISPLAY + 3,
56         ANDROID_PRIORITY_URGENT_DISPLAY + 2,
57         ANDROID_PRIORITY_URGENT_DISPLAY  // 10 (MAX_PRIORITY)
58 };
59 
PaletteSchedSetPriority(int32_t tid,int32_t managed_priority)60 palette_status_t PaletteSchedSetPriority(int32_t tid, int32_t managed_priority) {
61     if (managed_priority < art::palette::kMinManagedThreadPriority ||
62         managed_priority > art::palette::kMaxManagedThreadPriority) {
63         return PALETTE_STATUS_INVALID_ARGUMENT;
64     }
65     int new_nice = kNiceValues[managed_priority - art::palette::kMinManagedThreadPriority];
66     int curr_nice = getpriority(PRIO_PROCESS, tid);
67 
68     if (curr_nice == new_nice) {
69         return PALETTE_STATUS_OK;
70     }
71 
72     if (new_nice >= ANDROID_PRIORITY_BACKGROUND) {
73         SetTaskProfiles(tid, {"SCHED_SP_SYSTEM"}, true);
74     } else if (curr_nice >= ANDROID_PRIORITY_BACKGROUND) {
75         SetTaskProfiles(tid, {"SCHED_SP_FOREGROUND"}, true);
76     }
77 
78     if (setpriority(PRIO_PROCESS, tid, new_nice) != 0) {
79         return PALETTE_STATUS_CHECK_ERRNO;
80     }
81     return PALETTE_STATUS_OK;
82 }
83 
PaletteSchedGetPriority(int32_t tid,int32_t * managed_priority)84 palette_status_t PaletteSchedGetPriority(int32_t tid, /*out*/ int32_t* managed_priority) {
85     errno = 0;
86     int native_priority = getpriority(PRIO_PROCESS, tid);
87     if (native_priority == -1 && errno != 0) {
88         *managed_priority = art::palette::kNormalManagedThreadPriority;
89         return PALETTE_STATUS_CHECK_ERRNO;
90     }
91 
92     for (int p = art::palette::kMinManagedThreadPriority;
93          p <= art::palette::kMaxManagedThreadPriority; p = p + 1) {
94         int index = p - art::palette::kMinManagedThreadPriority;
95         if (native_priority >= kNiceValues[index]) {
96             *managed_priority = p;
97             return PALETTE_STATUS_OK;
98         }
99     }
100     *managed_priority = art::palette::kMaxManagedThreadPriority;
101     return PALETTE_STATUS_OK;
102 }
103 
PaletteWriteCrashThreadStacks(const char * stacks,size_t stacks_len)104 palette_status_t PaletteWriteCrashThreadStacks(/*in*/ const char* stacks, size_t stacks_len) {
105     android::base::unique_fd tombstone_fd;
106     android::base::unique_fd output_fd;
107 
108     if (!tombstoned_connect(getpid(), &tombstone_fd, &output_fd, kDebuggerdJavaBacktrace)) {
109         // Failure here could be due to file descriptor resource exhaustion
110         // so write the stack trace message to the log in case it helps
111         // debug that.
112         LOG(INFO) << std::string_view(stacks, stacks_len);
113         // tombstoned_connect() logs failure reason.
114         return PALETTE_STATUS_FAILED_CHECK_LOG;
115     }
116 
117     palette_status_t status = PALETTE_STATUS_OK;
118     if (!android::base::WriteFully(output_fd, stacks, stacks_len)) {
119         PLOG(ERROR) << "Failed to write tombstoned output";
120         TEMP_FAILURE_RETRY(ftruncate(output_fd, 0));
121         status = PALETTE_STATUS_FAILED_CHECK_LOG;
122     }
123 
124     if (TEMP_FAILURE_RETRY(fdatasync(output_fd)) == -1 && errno != EINVAL) {
125         // Ignore EINVAL so we don't report failure if we just tried to flush a pipe
126         // or socket.
127         if (status == PALETTE_STATUS_OK) {
128             PLOG(ERROR) << "Failed to fsync tombstoned output";
129             status = PALETTE_STATUS_FAILED_CHECK_LOG;
130         }
131         TEMP_FAILURE_RETRY(ftruncate(output_fd, 0));
132         TEMP_FAILURE_RETRY(fdatasync(output_fd));
133     }
134 
135     if (close(output_fd.release()) == -1 && errno != EINTR) {
136         if (status == PALETTE_STATUS_OK) {
137             PLOG(ERROR) << "Failed to close tombstoned output";
138             status = PALETTE_STATUS_FAILED_CHECK_LOG;
139         }
140     }
141 
142     if (!tombstoned_notify_completion(tombstone_fd)) {
143         // tombstoned_notify_completion() logs failure.
144         status = PALETTE_STATUS_FAILED_CHECK_LOG;
145     }
146 
147     return status;
148 }
149 
PaletteTraceEnabled(bool * enabled)150 palette_status_t PaletteTraceEnabled(/*out*/ bool* enabled) {
151     *enabled = (ATRACE_ENABLED() != 0) ? true : false;
152     return PALETTE_STATUS_OK;
153 }
154 
PaletteTraceBegin(const char * name)155 palette_status_t PaletteTraceBegin(const char* name) {
156     ATRACE_BEGIN(name);
157     return PALETTE_STATUS_OK;
158 }
159 
PaletteTraceEnd()160 palette_status_t PaletteTraceEnd() {
161     ATRACE_END();
162     return PALETTE_STATUS_OK;
163 }
164 
PaletteTraceIntegerValue(const char * name,int32_t value)165 palette_status_t PaletteTraceIntegerValue(const char* name, int32_t value) {
166     ATRACE_INT(name, value);
167     return PALETTE_STATUS_OK;
168 }
169 
170 // Flag whether to use legacy ashmem or current (b/139855428)
171 static std::atomic_bool g_assume_legacy_ashmemd(false);
172 
PaletteAshmemCreateRegion(const char * name,size_t size,int * fd)173 palette_status_t PaletteAshmemCreateRegion(const char* name, size_t size, int* fd) {
174     if (g_assume_legacy_ashmemd.load(std::memory_order_acquire) == false) {
175         // Current platform behaviour which open ashmem fd in process (b/139855428)
176         *fd = ashmem_create_region(name, size);
177         if (*fd >= 0) {
178             return PALETTE_STATUS_OK;
179         }
180     }
181 
182     // Try legacy behavior just required for ART build bots which may be running tests on older
183     // platform builds.
184 
185     // We implement our own ashmem creation, as the libcutils implementation does
186     // a binder call, and our only use of ashmem in ART is for zygote, which
187     // cannot communicate to binder.
188     *fd = TEMP_FAILURE_RETRY(open("/dev/ashmem", O_RDWR | O_CLOEXEC));
189     if (*fd == -1) {
190         return PALETTE_STATUS_CHECK_ERRNO;
191     }
192 
193     if (TEMP_FAILURE_RETRY(ioctl(*fd, ASHMEM_SET_SIZE, size)) < 0) {
194         goto error;
195     }
196 
197     if (name != nullptr) {
198         char buf[ASHMEM_NAME_LEN] = {0};
199         strlcpy(buf, name, sizeof(buf));
200         if (TEMP_FAILURE_RETRY(ioctl(*fd, ASHMEM_SET_NAME, buf)) < 0) {
201             goto error;
202         }
203     }
204 
205     g_assume_legacy_ashmemd.store(true, std::memory_order_release);
206     return PALETTE_STATUS_OK;
207 
208 error:
209     // Save errno before closing.
210     int save_errno = errno;
211     close(*fd);
212     errno = save_errno;
213     return PALETTE_STATUS_CHECK_ERRNO;
214 }
215 
PaletteAshmemSetProtRegion(int fd,int prot)216 palette_status_t PaletteAshmemSetProtRegion(int fd, int prot) {
217     if (!g_assume_legacy_ashmemd.load(std::memory_order_acquire)) {
218         if (ashmem_set_prot_region(fd, prot) < 0) {
219             return PALETTE_STATUS_CHECK_ERRNO;
220         }
221     } else if (TEMP_FAILURE_RETRY(ioctl(fd, ASHMEM_SET_PROT_MASK, prot)) < 0) {
222         // Legacy behavior just required for ART build bots which may be running tests on older
223         // platform builds.
224         return PALETTE_STATUS_CHECK_ERRNO;
225     }
226     return PALETTE_STATUS_OK;
227 }
228 
PaletteCreateOdrefreshStagingDirectory(const char ** staging_dir)229 palette_status_t PaletteCreateOdrefreshStagingDirectory(const char** staging_dir) {
230     static constexpr const char* kStagingDirectory = "/data/misc/apexdata/com.android.art/staging";
231 
232     std::error_code ec;
233     if (std::filesystem::exists(kStagingDirectory, ec)) {
234         if (!std::filesystem::remove_all(kStagingDirectory, ec)) {
235             LOG(ERROR) << ec.message()
236                        << "Could not remove existing staging directory: " << kStagingDirectory;
237             DCHECK_EQ(ec.value(), errno);
238             return PALETTE_STATUS_CHECK_ERRNO;
239         }
240     }
241 
242     if (mkdir(kStagingDirectory, S_IRWXU) != 0) {
243         PLOG(ERROR) << "Could not set permissions on staging directory: " << kStagingDirectory;
244         return PALETTE_STATUS_CHECK_ERRNO;
245     }
246 
247     if (setfilecon(kStagingDirectory, "u:object_r:apex_art_staging_data_file:s0") != 0) {
248         PLOG(ERROR) << "Could not set label on staging directory: " << kStagingDirectory;
249         return PALETTE_STATUS_CHECK_ERRNO;
250     }
251 
252     *staging_dir = kStagingDirectory;
253     return PALETTE_STATUS_OK;
254 }
255