xref: /sqlite-3.40.0/test/dbfuzz2.c (revision 8ed07d12)
1 /*
2 ** 2018-10-26
3 **
4 ** The author disclaims copyright to this source code.  In place of
5 ** a legal notice, here is a blessing:
6 **
7 **    May you do good and not evil.
8 **    May you find forgiveness for yourself and forgive others.
9 **    May you share freely, never taking more than you give.
10 **
11 *************************************************************************
12 **
13 ** This program is designed for fuzz-testing SQLite database files using
14 ** the -fsanitize=fuzzer option of clang.
15 **
16 ** The -fsanitize=fuzzer option causes a main() to be inserted automatically.
17 ** That main() invokes LLVMFuzzerTestOneInput(D,S) to be invoked repeatedly.
18 ** Each D is a fuzzed database file.  The code in this file runs various
19 ** SQL statements against that database, trying to provoke a failure.
20 **
21 ** For best results the seed database files should have these tables:
22 **
23 **   Table "t1" with columns "a" and "b"
24 **   Tables "t2" and "t3 with the same number of compatible columns
25 **       "t3" should have a column names "x"
26 **   Table "t4" with a column "x" that is compatible with t3.x.
27 **
28 ** Any of these tables can be virtual tables, for example FTS or RTree tables.
29 **
30 ** To run this test:
31 **
32 **     mkdir dir
33 **     cp dbfuzz2-seed*.db dir
34 **     clang-6.0 -I. -g -O1 -fsanitize=fuzzer \
35 **       -DTHREADSAFE=0 -DSQLITE_ENABLE_DESERIALIZE \
36 **       -DSQLITE_ENABLE_DBSTAT_VTAB dbfuzz2.c sqlite3.c -ldl
37 **     ./a.out dir
38 */
39 #include <assert.h>
40 #include <stdio.h>
41 #include <stdlib.h>
42 #include <string.h>
43 #include <stdarg.h>
44 #include <ctype.h>
45 #include <stdint.h>
46 #include <sys/time.h>
47 #include <sys/resource.h>
48 #include "sqlite3.h"
49 
50 /*
51 ** This is the is the SQL that is run against the database.
52 */
53 static const char *azSql[] = {
54   "PRAGMA integrity_check;",
55   "SELECT * FROM sqlite_master;",
56   "SELECT sum(length(name)) FROM dbstat;",
57   "UPDATE t1 SET b=a, a=b WHERE a<b;",
58   "ALTER TABLE t1 RENAME TO alkjalkjdfiiiwuer987lkjwer82mx97sf98788s9789s;",
59   "INSERT INTO t3 SELECT * FROM t2;",
60   "DELETE FROM t3 WHERE x IN (SELECT x FROM t4);",
61   "REINDEX;",
62   "DROP TABLE t3;",
63   "VACUUM;",
64 };
65 
66 /* Output verbosity level.  0 means complete silence */
67 int eVerbosity = 0;
68 
69 /* True to activate PRAGMA vdbe_debug=on */
70 static int bVdbeDebug = 0;
71 
72 /* libFuzzer invokes this routine with fuzzed database files (in aData).
73 ** This routine run SQLite against the malformed database to see if it
74 ** can provoke a failure or malfunction.
75 */
76 int LLVMFuzzerTestOneInput(const uint8_t *aData, size_t nByte){
77   unsigned char *a;
78   sqlite3 *db;
79   int rc;
80   int i;
81 
82   if( eVerbosity>=1 ){
83     printf("************** nByte=%d ***************\n", (int)nByte);
84     fflush(stdout);
85   }
86   if( sqlite3_initialize() ) return 0;
87   rc = sqlite3_open(0, &db);
88   if( rc ) return 1;
89   a = sqlite3_malloc64(nByte+1);
90   if( a==0 ) return 1;
91   memcpy(a, aData, nByte);
92   sqlite3_deserialize(db, "main", a, nByte, nByte,
93         SQLITE_DESERIALIZE_RESIZEABLE |
94         SQLITE_DESERIALIZE_FREEONCLOSE);
95   if( bVdbeDebug ){
96     sqlite3_exec(db, "PRAGMA vdbe_debug=ON", 0, 0, 0);
97   }
98   for(i=0; i<sizeof(azSql)/sizeof(azSql[0]); i++){
99     if( eVerbosity>=1 ){
100       printf("%s\n", azSql[i]);
101       fflush(stdout);
102     }
103     sqlite3_exec(db, azSql[i], 0, 0, 0);
104   }
105   rc = sqlite3_close(db);
106   if( rc!=SQLITE_OK ){
107     fprintf(stdout, "sqlite3_close() returns %d\n", rc);
108   }
109   if( sqlite3_memory_used()!=0 ){
110     int nAlloc = 0;
111     int nNotUsed = 0;
112     sqlite3_status(SQLITE_STATUS_MALLOC_COUNT, &nAlloc, &nNotUsed, 0);
113     fprintf(stderr,"Memory leak: %lld bytes in %d allocations\n",
114             sqlite3_memory_used(), nAlloc);
115     exit(1);
116   }
117   return 0;
118 }
119 
120 /*
121 ** Return the number of "v" characters in a string.  Return 0 if there
122 ** are any characters in the string other than "v".
123 */
124 static int numberOfVChar(const char *z){
125   int N = 0;
126   while( z[0] && z[0]=='v' ){
127     z++;
128     N++;
129   }
130   return z[0]==0 ? N : 0;
131 }
132 
133 /* libFuzzer invokes this routine once when the executable starts, to
134 ** process the command-line arguments.
135 */
136 int LLVMFuzzerInitialize(int *pArgc, char ***pArgv){
137   int i, j, n;
138   int argc = *pArgc;
139   char **argv = *pArgv;
140   for(i=j=1; i<argc; i++){
141     char *z = argv[i];
142     if( z[0]=='-' ){
143       z++;
144       if( z[0]=='-' ) z++;
145       if( z[0]=='v' && (n = numberOfVChar(z))>0 ){
146         eVerbosity += n;
147         continue;
148       }
149       if( strcmp(z,"vdbe-debug")==0 ){
150         bVdbeDebug = 1;
151         continue;
152       }
153       if( strcmp(z,"max-stack")==0 ){
154         struct rlimit x,y;
155         if( i+1==argc ){
156           fprintf(stderr, "missing argument to %s\n", argv[i]);
157           exit(1);
158         }
159         memset(&x,0,sizeof(x));
160         getrlimit(RLIMIT_STACK, &x);
161         y.rlim_cur = atoi(argv[++i]);
162         y.rlim_max = x.rlim_cur;
163         setrlimit(RLIMIT_STACK, &y);
164         memset(&y,0,sizeof(y));
165         getrlimit(RLIMIT_STACK, &y);
166         printf("Stack size limit changed from %d to %d\n",
167                (int)x.rlim_cur, (int)y.rlim_cur);
168         continue;
169       }
170     }
171     argv[j++] = argv[i];
172   }
173   argv[j] = 0;
174   *pArgc = j;
175   return 0;
176 }
177 
178 #ifdef STANDALONE
179 /*
180 ** Read an entire file into memory.  Space to hold the file comes
181 ** from malloc().
182 */
183 static unsigned char *readFile(const char *zName, int *pnByte){
184   FILE *in = fopen(zName, "rb");
185   long nIn;
186   size_t nRead;
187   unsigned char *pBuf;
188   if( in==0 ) return 0;
189   fseek(in, 0, SEEK_END);
190   nIn = ftell(in);
191   rewind(in);
192   pBuf = malloc( nIn+1 );
193   if( pBuf==0 ){ fclose(in); return 0; }
194   nRead = fread(pBuf, nIn, 1, in);
195   fclose(in);
196   if( nRead!=1 ){
197     free(pBuf);
198     return 0;
199   }
200   pBuf[nIn] = 0;
201   if( pnByte ) *pnByte = nIn;
202   return pBuf;
203 }
204 #endif /* STANDALONE */
205 
206 #ifdef STANDALONE
207 int main(int argc, char **argv){
208   int i;
209   LLVMFuzzerInitialize(&argc, &argv);
210   for(i=1; i<argc; i++){
211     unsigned char *pIn;
212     int nIn;
213     pIn = readFile(argv[i], &nIn);
214     if( pIn ){
215       LLVMFuzzerTestOneInput((const uint8_t*)pIn, (size_t)nIn);
216       free(pIn);
217     }
218   }
219   if( eVerbosity>0 ){
220     printf("SQLite %s\n", sqlite3_sourceid());
221   }
222   return 0;
223 }
224 #endif /*STANDALONE*/
225