f2408e6c3
Denis Vlasenko
2006-11-25
Subject
tar: abort if tarring up file larger that 64Gb (otherwise we will produce garbled tarfile)
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Architecture & Compiler Flags
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Build Log
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Commit Diff GitHub →
archival/tar.c+35 -42
| @@ -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) */ |
| - | /* FIXME: we leave field untouched if value doesn't fit. */ |
| - | /* This is not good - what will happen at untar time?? */ |
| - | static void putOctal(char *cp, int len, long long value) |
| + | * Stores low-order bits only if whole value does not fit. |
| + | * Returns FALSE if that happens. */ |
| + | static int putOctal(char *cp, int len, off_t value) |
| { | |
| - | int tempLength; |
| - | /* 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 tempBuffer[sizeof(off_t)*3+1]; |
| char *tempString = tempBuffer; | |
| + | int width; |
| - | /* Create a string of the specified length with |
| - | * leading zeroes and the octal number, and a trailing null. */ |
| - | 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' */ |
| - | } |
| + | width = sprintf(tempBuffer, "%0*"OFF_FMT"o", len, value); |
| + | tempString += (width - len); |
| - | /* 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); |
| - | putOctal(header.uid, sizeof(header.uid), statbuf->st_uid); |
| - | putOctal(header.gid, sizeof(header.gid), statbuf->st_gid); |
| + | PUT_OCTAL(header.mode, statbuf->st_mode & 07777); |
| + | PUT_OCTAL(header.uid, statbuf->st_uid); |
| + | 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), |
| - | major(statbuf->st_rdev)); |
| - | putOctal(header.devminor, sizeof(header.devminor), |
| - | minor(statbuf->st_rdev)); |
| + | PUT_OCTAL(header.devmajor, major(statbuf->st_rdev)); |
| + | PUT_OCTAL(header.devminor, minor(statbuf->st_rdev)); |
| } else if (S_ISBLK(statbuf->st_mode)) { | |
| header.typeflag = BLKTYPE; | |
| - | putOctal(header.devmajor, sizeof(header.devmajor), |
| - | major(statbuf->st_rdev)); |
| - | putOctal(header.devminor, sizeof(header.devminor), |
| - | minor(statbuf->st_rdev)); |
| + | PUT_OCTAL(header.devmajor, major(statbuf->st_rdev)); |
| + | PUT_OCTAL(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 | |