tar: abort if tarring up file larger that 64Gb

(otherwise we will produce garbled tarfile)
author: Denis Vlasenko <vda.linux@googlemail.com> 2006-11-25 14:48:09 +0000
committer: Denis Vlasenko <vda.linux@googlemail.com> 2006-11-25 14:48:09 +0000
commit: f2408e6c3ff5f9f798bb5553346d9e1657dc9833 (patch)
tree: 29a7144d66c91086fb53278c40ee1b27f4006cd7 /archival/tar.c
parent: 5dd27b1ee0518f4f886e6140adc5d1f20fb770e2 (diff)
download: busybox-w32-f2408e6c3ff5f9f798bb5553346d9e1657dc9833.tar.gz
busybox-w32-f2408e6c3ff5f9f798bb5553346d9e1657dc9833.tar.bz2
busybox-w32-f2408e6c3ff5f9f798bb5553346d9e1657dc9833.zip
1 files changed, 35 insertions, 42 deletions
diff --git a/archival/tar.c b/archival/tar.c
index b326d1e88..d875805b0 100644
--- a/archival/tar.c
+++ b/archival/tar.c
@@ -150,40 +150,29 @@ static HardLinkInfo *findHardLinkInfo(HardLinkInfo * hlInfo, struct stat *statbu
 /* Put an octal string into the specified buffer.
 * The number is zero padded and possibly null terminated.
- * Returns TRUE if successful. - DISABLED (no caller ever checked) */
+ * Stores low-order bits only if whole value does not fit.
-/* FIXME: we leave field untouched if value doesn't fit. */
+ * Returns FALSE if that happens.  */
-/* This is not good - what will happen at untar time?? */
+static int putOctal(char *cp, int len, off_t value)
-static void putOctal(char *cp, int len, long long value)
 {
-        int tempLength;
+        char tempBuffer[sizeof(off_t)*3+1];
-        /* long long for the sake of storing lengths of 4Gb+ files */
-        /* (we are bust anyway after 64Gb: it doesn't fit into the field) */
-        char tempBuffer[sizeof(long long)*3+1];
        char *tempString = tempBuffer;
+        int width;
-        /* Create a string of the specified length with
+        width = sprintf(tempBuffer, "%0*"OFF_FMT"o", len, value);
-         * leading zeroes and the octal number, and a trailing null.  */
+        tempString += (width - len);
-        tempLength = sprintf(tempBuffer, "%0*llo", len - 1, value);
-        /* If the string is too large, suppress leading 0's.  */
-        /* If that is not enough, drop trailing null.  */
-        tempLength -= len; /* easier to do checks */
-        while (tempLength >= 0) {
-                if (tempString[0] != '0') {
-                        if (!tempLength) {
-                                /* 1234 barely fits in 4 chars (w/o EOL '\0') */
-                                break;
-                        }
-                        /* 12345 doesn't fit into 4 chars */
-                        return /*FALSE*/;
-                }
-                tempLength--; /* still have leading '0', */
-                tempString++; /* can afford to drop it but retain EOL '\0' */
-        }
-        /* Copy the string to the field.  */
+        /* If string has leading zeroes, we can drop one */
+        /* and field will have trailing '\0' */
+        /* (increases chances of compat with other tars) */
+        if (tempString[0] == '0')
+                tempString++;
+        /* Copy the string to the field */
        memcpy(cp, tempString, len);
-        /*return TRUE;*/
+        /* If after shift we have zero - value did not overflow, */
+        /* return 1 (TRUE) then */
+        return (value >> (len*3)) == 0;
 }
 /* Write out a tar header for the specified file/directory/whatever */
@@ -203,12 +192,13 @@ static int writeTarHeader(struct TarBallInfo *tbInfo,
        safe_strncpy(header.name, header_name, sizeof(header.name));
+#define PUT_OCTAL(a, b) putOctal((a), sizeof(a), (b))
        /* POSIX says to mask mode with 07777. */
-        putOctal(header.mode, sizeof(header.mode), statbuf->st_mode & 07777);
+        PUT_OCTAL(header.mode, statbuf->st_mode & 07777);
-        putOctal(header.uid, sizeof(header.uid), statbuf->st_uid);
+        PUT_OCTAL(header.uid, statbuf->st_uid);
-        putOctal(header.gid, sizeof(header.gid), statbuf->st_gid);
+        PUT_OCTAL(header.gid, statbuf->st_gid);
        memset(header.size, '0', sizeof(header.size)-1); /* Regular file size is handled later */
-        putOctal(header.mtime, sizeof(header.mtime), statbuf->st_mtime);
+        PUT_OCTAL(header.mtime, statbuf->st_mtime);
        strcpy(header.magic, "ustar  ");
        /* Enter the user and group names */
@@ -240,25 +230,28 @@ static int writeTarHeader(struct TarBallInfo *tbInfo,
                strncat(header.name, "/", sizeof(header.name));
        } else if (S_ISCHR(statbuf->st_mode)) {
                header.typeflag = CHRTYPE;
-                putOctal(header.devmajor, sizeof(header.devmajor),
+                PUT_OCTAL(header.devmajor, major(statbuf->st_rdev));
-                                 major(statbuf->st_rdev));
+                PUT_OCTAL(header.devminor, minor(statbuf->st_rdev));
-                putOctal(header.devminor, sizeof(header.devminor),
-                                 minor(statbuf->st_rdev));
        } else if (S_ISBLK(statbuf->st_mode)) {
                header.typeflag = BLKTYPE;
-                putOctal(header.devmajor, sizeof(header.devmajor),
+                PUT_OCTAL(header.devmajor, major(statbuf->st_rdev));
-                                 major(statbuf->st_rdev));
+                PUT_OCTAL(header.devminor, minor(statbuf->st_rdev));
-                putOctal(header.devminor, sizeof(header.devminor),
-                                 minor(statbuf->st_rdev));
        } else if (S_ISFIFO(statbuf->st_mode)) {
                header.typeflag = FIFOTYPE;
        } else if (S_ISREG(statbuf->st_mode)) {
                header.typeflag = REGTYPE;
-                putOctal(header.size, sizeof(header.size), statbuf->st_size);
+                if ((PUT_OCTAL(header.size, statbuf->st_size) == FALSE)
+                 && sizeof(statbuf->st_size) > 4
+                ) {
+                        bb_error_msg_and_die("cannot store file '%s' "
+                                "of size %"OFF_FMT"d, aborting",
+                                fileName, statbuf->st_size);
+                }
        } else {
                bb_error_msg("%s: unknown file type", fileName);
                return FALSE;
        }
+#undef PUT_OCTAL
        /* Calculate and store the checksum (i.e., the sum of all of the bytes of
         * the header).  The checksum field must be filled with blanks for the
author	Denis Vlasenko <vda.linux@googlemail.com>	2006-11-25 14:48:09 +0000
committer	Denis Vlasenko <vda.linux@googlemail.com>	2006-11-25 14:48:09 +0000
commit	f2408e6c3ff5f9f798bb5553346d9e1657dc9833 (patch)
tree	29a7144d66c91086fb53278c40ee1b27f4006cd7 /archival/tar.c
parent	5dd27b1ee0518f4f886e6140adc5d1f20fb770e2 (diff)
download	busybox-w32-f2408e6c3ff5f9f798bb5553346d9e1657dc9833.tar.gz busybox-w32-f2408e6c3ff5f9f798bb5553346d9e1657dc9833.tar.bz2 busybox-w32-f2408e6c3ff5f9f798bb5553346d9e1657dc9833.zip

diff --git a/archival/tar.c b/archival/tar.c index b326d1e88..d875805b0 100644 --- a/archival/tar.c +++ b/archival/tar.c
@@ -150,40 +150,29 @@ static HardLinkInfo findHardLinkInfo(HardLinkInfo hlInfo, struct stat *statbu
150		150
151	/* Put an octal string into the specified buffer.	151	/* Put an octal string into the specified buffer.
152	* The number is zero padded and possibly null terminated.	152	* The number is zero padded and possibly null terminated.
153	* Returns TRUE if successful. - DISABLED (no caller ever checked) */	153	* Stores low-order bits only if whole value does not fit.
154	/* FIXME: we leave field untouched if value doesn't fit. */	154	* Returns FALSE if that happens. */
155	/* This is not good - what will happen at untar time?? */	155	static int putOctal(char *cp, int len, off_t value)
156	static void putOctal(char *cp, int len, long long value)
157	{	156	{
158	int tempLength;	157	char tempBuffer[sizeof(off_t)*3+1];
159	/* long long for the sake of storing lengths of 4Gb+ files */
160	/* (we are bust anyway after 64Gb: it doesn't fit into the field) */
161	char tempBuffer[sizeof(long long)*3+1];
162	char *tempString = tempBuffer;	158	char *tempString = tempBuffer;
		159	int width;
163		160
164	/* Create a string of the specified length with	161	width = sprintf(tempBuffer, "%0*"OFF_FMT"o", len, value);
165	* leading zeroes and the octal number, and a trailing null. */	162	tempString += (width - len);
166	tempLength = sprintf(tempBuffer, "%0*llo", len - 1, value);
167
168	/* If the string is too large, suppress leading 0's. */
169	/* If that is not enough, drop trailing null. */
170	tempLength -= len; /* easier to do checks */
171	while (tempLength >= 0) {
172	if (tempString[0] != '0') {
173	if (!tempLength) {
174	/* 1234 barely fits in 4 chars (w/o EOL '\0') */
175	break;
176	}
177	/* 12345 doesn't fit into 4 chars */
178	return /FALSE/;
179	}
180	tempLength--; /* still have leading '0', */
181	tempString++; /* can afford to drop it but retain EOL '\0' */
182	}
183		163
184	/* Copy the string to the field. */	164	/* If string has leading zeroes, we can drop one */
		165	/* and field will have trailing '\0' */
		166	/* (increases chances of compat with other tars) */
		167	if (tempString[0] == '0')
		168	tempString++;
		169
		170	/* Copy the string to the field */
185	memcpy(cp, tempString, len);	171	memcpy(cp, tempString, len);
186	/return TRUE;/	172
		173	/* If after shift we have zero - value did not overflow, */
		174	/* return 1 (TRUE) then */
		175	return (value >> (len*3)) == 0;
187	}	176	}
188		177
189	/* Write out a tar header for the specified file/directory/whatever */	178	/* Write out a tar header for the specified file/directory/whatever */
@@ -203,12 +192,13 @@ static int writeTarHeader(struct TarBallInfo *tbInfo,
203		192
204	safe_strncpy(header.name, header_name, sizeof(header.name));	193	safe_strncpy(header.name, header_name, sizeof(header.name));
205		194
		195	#define PUT_OCTAL(a, b) putOctal((a), sizeof(a), (b))
206	/* POSIX says to mask mode with 07777. */	196	/* POSIX says to mask mode with 07777. */
207	putOctal(header.mode, sizeof(header.mode), statbuf->st_mode & 07777);	197	PUT_OCTAL(header.mode, statbuf->st_mode & 07777);
208	putOctal(header.uid, sizeof(header.uid), statbuf->st_uid);	198	PUT_OCTAL(header.uid, statbuf->st_uid);
209	putOctal(header.gid, sizeof(header.gid), statbuf->st_gid);	199	PUT_OCTAL(header.gid, statbuf->st_gid);
210	memset(header.size, '0', sizeof(header.size)-1); /* Regular file size is handled later */	200	memset(header.size, '0', sizeof(header.size)-1); /* Regular file size is handled later */
211	putOctal(header.mtime, sizeof(header.mtime), statbuf->st_mtime);	201	PUT_OCTAL(header.mtime, statbuf->st_mtime);
212	strcpy(header.magic, "ustar ");	202	strcpy(header.magic, "ustar ");
213		203
214	/* Enter the user and group names */	204	/* Enter the user and group names */
@@ -240,25 +230,28 @@ static int writeTarHeader(struct TarBallInfo *tbInfo,
240	strncat(header.name, "/", sizeof(header.name));	230	strncat(header.name, "/", sizeof(header.name));
241	} else if (S_ISCHR(statbuf->st_mode)) {	231	} else if (S_ISCHR(statbuf->st_mode)) {
242	header.typeflag = CHRTYPE;	232	header.typeflag = CHRTYPE;
243	putOctal(header.devmajor, sizeof(header.devmajor),	233	PUT_OCTAL(header.devmajor, major(statbuf->st_rdev));
244	major(statbuf->st_rdev));	234	PUT_OCTAL(header.devminor, minor(statbuf->st_rdev));
245	putOctal(header.devminor, sizeof(header.devminor),
246	minor(statbuf->st_rdev));
247	} else if (S_ISBLK(statbuf->st_mode)) {	235	} else if (S_ISBLK(statbuf->st_mode)) {
248	header.typeflag = BLKTYPE;	236	header.typeflag = BLKTYPE;
249	putOctal(header.devmajor, sizeof(header.devmajor),	237	PUT_OCTAL(header.devmajor, major(statbuf->st_rdev));
250	major(statbuf->st_rdev));	238	PUT_OCTAL(header.devminor, minor(statbuf->st_rdev));
251	putOctal(header.devminor, sizeof(header.devminor),
252	minor(statbuf->st_rdev));
253	} else if (S_ISFIFO(statbuf->st_mode)) {	239	} else if (S_ISFIFO(statbuf->st_mode)) {
254	header.typeflag = FIFOTYPE;	240	header.typeflag = FIFOTYPE;
255	} else if (S_ISREG(statbuf->st_mode)) {	241	} else if (S_ISREG(statbuf->st_mode)) {
256	header.typeflag = REGTYPE;	242	header.typeflag = REGTYPE;
257	putOctal(header.size, sizeof(header.size), statbuf->st_size);	243	if ((PUT_OCTAL(header.size, statbuf->st_size) == FALSE)
		244	&& sizeof(statbuf->st_size) > 4
		245	) {
		246	bb_error_msg_and_die("cannot store file '%s' "
		247	"of size %"OFF_FMT"d, aborting",
		248	fileName, statbuf->st_size);
		249	}
258	} else {	250	} else {
259	bb_error_msg("%s: unknown file type", fileName);	251	bb_error_msg("%s: unknown file type", fileName);
260	return FALSE;	252	return FALSE;
261	}	253	}
		254	#undef PUT_OCTAL
262		255
263	/* Calculate and store the checksum (i.e., the sum of all of the bytes of	256	/* Calculate and store the checksum (i.e., the sum of all of the bytes of
264	* the header). The checksum field must be filled with blanks for the	257	* the header). The checksum field must be filled with blanks for the