Bug Summary

File:bin/tools/mimegen.c
Warning:line 280, column 17
Potential leak of memory pointed to by 'k'

Annotated Source Code

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clang -cc1 -cc1 -triple x86_64-pc-linux-gnu -analyze -disable-free -clear-ast-before-backend -disable-llvm-verifier -discard-value-names -main-file-name mimegen.c -analyzer-store=region -analyzer-opt-analyze-nested-blocks -analyzer-checker=core -analyzer-checker=apiModeling -analyzer-checker=unix -analyzer-checker=deadcode -analyzer-checker=security.insecureAPI.UncheckedReturn -analyzer-checker=security.insecureAPI.getpw -analyzer-checker=security.insecureAPI.gets -analyzer-checker=security.insecureAPI.mktemp -analyzer-checker=security.insecureAPI.mkstemp -analyzer-checker=security.insecureAPI.vfork -analyzer-checker=nullability.NullPassedToNonnull -analyzer-checker=nullability.NullReturnedFromNonnull -analyzer-output plist -w -setup-static-analyzer -mrelocation-model pic -pic-level 2 -pic-is-pie -mframe-pointer=all -fmath-errno -ffp-contract=on -fno-rounding-math -mconstructor-aliases -fno-plt -funwind-tables=2 -target-cpu x86-64 -tune-cpu generic -debugger-tuning=gdb -fcoverage-compilation-dir=/home/buildbot/lwan-worker/clang-analyze/build/src/bin/tools -resource-dir /usr/lib/clang/14.0.6 -include /home/buildbot/lwan-worker/clang-analyze/build/lwan-build-config.h -D _FILE_OFFSET_BITS=64 -D _TIME_BITS=64 -I /home/buildbot/lwan-worker/clang-analyze/build/src/lib/missing -I /usr/include/luajit-2.1 -I /usr/include/valgrind -I /home/buildbot/lwan-worker/clang-analyze/build/src/lib -internal-isystem /usr/lib/clang/14.0.6/include -internal-isystem /usr/local/include -internal-isystem /usr/bin/../lib64/gcc/x86_64-pc-linux-gnu/12.2.0/../../../../x86_64-pc-linux-gnu/include -internal-externc-isystem /include -internal-externc-isystem /usr/include -Wno-unused-parameter -Wno-free-nonheap-object -std=gnu11 -fdebug-compilation-dir=/home/buildbot/lwan-worker/clang-analyze/build/src/bin/tools -ferror-limit 19 -stack-protector 2 -fgnuc-version=4.2.1 -analyzer-output=html -faddrsig -D__GCC_HAVE_DWARF2_CFI_ASM=1 -o /home/buildbot/lwan-worker/clang-analyze/CLANG/2023-01-03-043944-1058096-1 -x c /home/buildbot/lwan-worker/clang-analyze/build/src/bin/tools/mimegen.c
1/*
2 * lwan - web server
3 * Copyright (c) 2016 L. A. F. Pereira <l@tia.mat.br>
4 *
5 * This program is free software; you can redistribute it and/or
6 * modify it under the terms of the GNU General Public License
7 * as published by the Free Software Foundation; either version 2
8 * of the License, or any later version.
9 *
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 * GNU General Public License for more details.
14 *
15 * You should have received a copy of the GNU General Public License
16 * along with this program; if not, write to the Free Software
17 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
18 */
19
20#include <assert.h>
21#include <ctype.h>
22#include <errno(*__errno_location ()).h>
23#include <fcntl.h>
24#include <stdint.h>
25#include <stdio.h>
26#include <stdlib.h>
27#include <string.h>
28
29#if defined(LWAN_HAVE_BROTLI)
30#include <brotli/encode.h>
31#elif defined(LWAN_HAVE_ZSTD)
32#include <zstd.h>
33#elif defined(LWAN_HAVE_ZOPFLI)
34#include <zopfli/zopfli.h>
35#else
36#include <zlib.h>
37#endif
38
39#include "../../lib/hash.h"
40
41struct output {
42 char *ptr;
43 size_t used, capacity;
44};
45
46static int
47output_append_full(struct output *output, const char *str, size_t str_len)
48{
49 size_t total_size = output->used + str_len;
50
51 if (total_size >= output->capacity) {
52 char *tmp;
53
54 while (total_size >= output->capacity)
55 output->capacity *= 2;
56
57 tmp = realloc(output->ptr, output->capacity);
58 if (!tmp)
59 return -errno(*__errno_location ());
60
61 output->ptr = tmp;
62 }
63
64 memcpy(output->ptr + output->used, str, str_len);
65 output->used = total_size;
66
67 return 0;
68}
69
70static int output_append_padded(struct output *output, const char *str)
71{
72 size_t str_len = strlen(str);
73
74 assert(str_len <= 8)__builtin_assume(str_len <= 8);
75
76 int r = output_append_full(output, str, str_len);
77 if (r < 0)
78 return r;
79
80 if (str_len != 8)
81 return output_append_full(output, "\0\0\0\0\0\0\0\0", 8 - str_len);
82
83 return 0;
84}
85
86static int output_append(struct output *output, const char *str)
87{
88 return output_append_full(output, str, strlen(str) + 1);
89}
90
91static int compare_ext(const void *a, const void *b)
92{
93 const char **exta = (const char **)a;
94 const char **extb = (const char **)b;
95
96 return strcasecmp(*exta, *extb);
97}
98
99static char *strend(char *str, char ch)
100{
101 str = strchr(str, ch);
102 if (str) {
103 *str = '\0';
104 return str + 1;
105 }
106 return NULL((void*)0);
107}
108
109static char *compress_output(const struct output *output, size_t *outlen)
110{
111 char *compressed;
112
113#if defined(LWAN_HAVE_BROTLI)
114 *outlen = BrotliEncoderMaxCompressedSize(output->used);
115
116 compressed = malloc(*outlen);
117 if (!compressed) {
118 fprintf(stderrstderr, "Could not allocate memory for compressed data\n");
119 exit(1);
120 }
121
122 if (BrotliEncoderCompress(BROTLI_MAX_QUALITY11, BROTLI_MAX_WINDOW_BITS24,
123 BROTLI_MODE_TEXT, output->used,
124 (const unsigned char *)output->ptr, outlen,
125 (unsigned char *)compressed) != BROTLI_TRUE1) {
126 fprintf(stderrstderr, "Could not compress mime type table with Brotli\n");
127 exit(1);
128 }
129#elif defined(LWAN_HAVE_ZSTD)
130 *outlen = ZSTD_compressBound(output->used);
131
132 compressed = malloc(*outlen);
133 if (!compressed) {
134 fprintf(stderrstderr, "Could not allocate memory for compressed data\n");
135 exit(1);
136 }
137
138 *outlen = ZSTD_compress(compressed, *outlen, output->ptr, output->used,
139 ZSTD_maxCLevel());
140 if (ZSTD_isError(*outlen)) {
141 fprintf(stderrstderr, "Could not compress mime type table with ZSTD\n");
142 exit(1);
143 }
144#elif defined(LWAN_HAVE_ZOPFLI)
145 ZopfliOptions opts;
146
147 *outlen = 0;
148
149 ZopfliInitOptions(&opts);
150 ZopfliCompress(&opts, ZOPFLI_FORMAT_ZLIB,
151 (const unsigned char *)output->ptr, output->used,
152 (unsigned char **)&compressed, outlen);
153#else
154 *outlen = compressBound((uLong)output->used);
155 compressed = malloc(*outlen);
156 if (!compressed) {
157 fprintf(stderrstderr, "Could not allocate memory for compressed data\n");
158 exit(1);
159 }
160 if (compress2((Bytef *)compressed, outlen, (const Bytef *)output->ptr,
161 output->used, 9) != Z_OK) {
162 fprintf(stderrstderr, "Could not compress data with zlib\n");
163 exit(1);
164 }
165#endif
166 if (!*outlen) {
167 free(compressed);
168 return NULL((void*)0);
169 }
170
171 return compressed;
172}
173
174static bool_Bool is_builtin_ext(const char *ext)
175{
176 /* STRING_SWITCH_L() is not used here to not bring in lwan.h */
177 /* FIXME: maybe use an X-macro to keep in sync with lwan-tables.c? */
178 if (strcaseequal_neutral(ext, "css"))
179 return true1;
180 if (strcaseequal_neutral(ext, "gif"))
181 return true1;
182 if (strcaseequal_neutral(ext, "htm"))
183 return true1;
184 if (strcaseequal_neutral(ext, "html"))
185 return true1;
186 if (strcaseequal_neutral(ext, "jpg"))
187 return true1;
188 if (strcaseequal_neutral(ext, "js"))
189 return true1;
190 if (strcaseequal_neutral(ext, "png"))
191 return true1;
192 if (strcaseequal_neutral(ext, "txt"))
193 return true1;
194 return false0;
195}
196
197int main(int argc, char *argv[])
198{
199 /* 32k is sufficient for the provided mime.types, but we can reallocate
200 * if necessary. This is just to avoid unneccessary reallocs. */
201 struct output output = { .capacity = 32768 };
202 FILE *fp;
203 char buffer[256];
204 size_t compressed_size;
205 char *compressed, *ext;
206 struct hash *ext_mime;
207 struct hash_iter iter;
208 const char **exts, *key;
209 size_t i;
210
211 if (argc < 2) {
1
Assuming 'argc' is >= 2
2
Taking false branch
212 fprintf(stderrstderr, "Usage: %s /path/to/mime.types\n", argv[0]);
213 return 1;
214 }
215
216 fp = fopen(argv[1], "re");
217 if (!fp) {
3
Assuming 'fp' is non-null
4
Taking false branch
218 fprintf(stderrstderr, "Could not open %s: %s\n", argv[1], strerror(errno(*__errno_location ())));
219 return 1;
220 }
221
222 ext_mime = hash_str_new(free, free);
223 if (!ext_mime) {
5
Assuming 'ext_mime' is non-null
6
Taking false branch
224 fprintf(stderrstderr, "Could not allocate hash table\n");
225 fclose(fp);
226 return 1;
227 }
228
229 while (fgets(buffer, sizeof(buffer), fp)) {
7
Loop condition is true. Entering loop body
230 char *start = buffer, *end, *tab, *mime_type;
231
232 while (*start && isspace(*start)((*__ctype_b_loc ())[(int) ((*start))] & (unsigned short int
) _ISspace)
) /* Strip spaces at the start. */
8
Assuming the condition is true
9
Loop condition is true. Entering loop body
10
Assuming the condition is false
233 start++;
234 if (*start == '#') /* Ignore commented-out lines. */
11
Taking false branch
235 continue;
236
237 strend(start, '\n'); /* Strip line endings. */
238 strend(start, '#'); /* Strip comments from the middle. */
239 tab = strend(start, '\t');
240 if (!tab
11.1
'tab' is non-null
) /* Find mime-type/extension separator. */
12
Taking false branch
241 continue;
242
243 mime_type = start;
244 /* "application/octet-stream" is the fallback, so no need to store
245 * it in the table. It's just one line, though, so maybe not really
246 * necessary? */
247 if (streq(mime_type, "application/octet-stream"))
248 continue;
249
250 while (*tab && *tab == '\t') /* Find first extension. */
13
Assuming the condition is true
14
Assuming the condition is false
15
Loop condition is false. Execution continues on line 253
251 tab++;
252
253 for (ext = tab; *ext; ext += end - ext + 1) {
16
Loop condition is true. Entering loop body
254 char *k, *v;
255 int r;
256
257 end = strchr(ext, ' '); /* Stop at next extension. */
258 if (!end)
17
Assuming 'end' is non-null
18
Taking false branch
259 end = strchr(ext, '\0'); /* If not found, find last extension. */
260 *end = '\0';
261
262 /* Check if we have empty extensions. Shouldn't happen with the provided
263 * mime.types file, but check on debug builds if this ever happens. */
264 assert(end != ext)__builtin_assume(end != ext);
265
266 if (end - ext > 8) {
19
Assuming the condition is false
20
Taking false branch
267 /* Truncate extensions over 8 characters. See commit 2050759297. */
268 ext[8] = '\0';
269 }
270
271 /* Lwan has a fast-path for some common extensions, so don't bundle them
272 * in this table if not really needed. */
273 if (is_builtin_ext(ext))
21
Assuming the condition is false
22
Taking false branch
274 continue;
275
276 k = strdup(ext);
23
Memory is allocated
277 v = strdup(mime_type);
278
279 if (!k || !v) {
24
Assuming 'k' is non-null
25
Assuming 'v' is null
26
Taking true branch
280 fprintf(stderrstderr, "Could not allocate memory\n");
27
Potential leak of memory pointed to by 'k'
281 fclose(fp);
282 return 1;
283 }
284
285 r = hash_add_unique(ext_mime, k, v);
286 if (r < 0) {
287 free(k);
288 free(v);
289
290 if (r != -EEXIST17) {
291 fprintf(stderrstderr, "Could not add extension to hash table\n");
292 fclose(fp);
293 return 1;
294 }
295 }
296 }
297 }
298
299 /* Get sorted list of extensions. */
300 exts = calloc(hash_get_count(ext_mime), sizeof(char *));
301 if (!exts) {
302 fprintf(stderrstderr, "Could not allocate extension array\n");
303 fclose(fp);
304 return 1;
305 }
306 hash_iter_init(ext_mime, &iter);
307 for (i = 0; hash_iter_next(&iter, (const void **)&key, NULL((void*)0)); i++)
308 exts[i] = key;
309 qsort(exts, hash_get_count(ext_mime), sizeof(char *), compare_ext);
310
311 /* Generate uncompressed blob. */
312 output.ptr = malloc(output.capacity);
313 if (!output.ptr) {
314 fprintf(stderrstderr, "Could not allocate temporary memory\n");
315 fclose(fp);
316 return 1;
317 }
318 for (i = 0; i < hash_get_count(ext_mime); i++) {
319 char ext_lower[9] = {0};
320
321 strncpy(ext_lower, exts[i], 8);
322
323 for (char *p = ext_lower; *p; p++)
324 *p &= ~0x20;
325
326 if (output_append_padded(&output, ext_lower) < 0) {
327 fprintf(stderrstderr, "Could not append to output\n");
328 fclose(fp);
329 return 1;
330 }
331 }
332 for (i = 0; i < hash_get_count(ext_mime); i++) {
333 if (output_append(&output, hash_find(ext_mime, exts[i])) < 0) {
334 fprintf(stderrstderr, "Could not append to output\n");
335 fclose(fp);
336 return 1;
337 }
338 }
339
340 /* Compress blob. */
341 compressed = compress_output(&output, &compressed_size);
342 if (!compressed) {
343 fprintf(stderrstderr, "Could not compress data\n");
344 fclose(fp);
345 return 1;
346 }
347
348 /* Print output. */
349#if defined(LWAN_HAVE_BROTLI)
350 printf("/* Compressed with brotli */\n");
351#elif defined(LWAN_HAVE_ZSTD)
352 printf("/* Compressed with zstd */\n");
353#elif defined(LWAN_HAVE_ZOPFLI)
354 printf("/* Compressed with zopfli (deflate) */\n");
355#else
356 printf("/* Compressed with zlib (deflate) */\n");
357#endif
358 printf("#pragma once\n");
359 printf("#define MIME_UNCOMPRESSED_LEN %zu\n", output.used);
360 printf("#define MIME_COMPRESSED_LEN %lu\n", compressed_size);
361 printf("#define MIME_ENTRIES %d\n", hash_get_count(ext_mime));
362 printf("static const unsigned char mime_entries_compressed[] = {\n");
363 for (i = 1; compressed_size; compressed_size--, i++)
364 printf("0x%02x,%c", compressed[i - 1] & 0xff, " \n"[i % 13 == 0]);
365 printf("};\n");
366
367 free(compressed);
368 free(output.ptr);
369 free(exts);
370 hash_free(ext_mime);
371 fclose(fp);
372
373 return 0;
374}