diff options
Diffstat (limited to 'lib/libpbm1.c')
| -rw-r--r-- | lib/libpbm1.c | 34 |
1 files changed, 30 insertions, 4 deletions
diff --git a/lib/libpbm1.c b/lib/libpbm1.c index 49ab7fdf..9e51970c 100644 --- a/lib/libpbm1.c +++ b/lib/libpbm1.c @@ -14,7 +14,7 @@ offset stuff. */ #define _FILE_OFFSET_BITS 64 -#define _LARGE_FILES +#define _LARGE_FILES #include <stdio.h> @@ -22,6 +22,7 @@ #include "netpbm/mallocvar.h" #include "netpbm/shhopt.h" +#include "libpbm.h" #include "pbm.h" @@ -59,7 +60,7 @@ pbm_nextimage(FILE *file, int * const eofP) { void pbm_check(FILE * const fileP, - enum pm_check_type const checkType, + enum pm_check_type const checkType, int const format, int const cols, int const rows, @@ -69,14 +70,14 @@ pbm_check(FILE * const fileP, pm_error("Invalid number of rows passed to pbm_check(): %d", rows); if (cols < 0) pm_error("Invalid number of columns passed to pbm_check(): %d", cols); - + if (checkType != PM_CHECK_BASIC) { if (retvalP) *retvalP = PM_CHECK_UNKNOWN_TYPE; } else if (format != RPBM_FORMAT) { if (retvalP) *retvalP = PM_CHECK_UNCHECKABLE; - } else { + } else { pm_filepos const bytesPerRow = (cols+7)/8; pm_filepos const needRasterSize = rows * bytesPerRow; pm_check(fileP, checkType, needRasterSize, retvalP); @@ -85,6 +86,28 @@ pbm_check(FILE * const fileP, +void +pbm_validateComputableSize(unsigned int const cols, + unsigned int const rows) { +/*---------------------------------------------------------------------------- + Validate that the dimensions of the image are such that it can be + processed in typical ways on this machine without worrying about + overflows. Note that in C, arithmetic is always modulus + arithmetic, so if your values are too big, the result is not what + you expect. That failed expectation can be disastrous if you use + it to allocate memory. + + See comments at 'validateComputableSize' in libpam.c for details on + the purpose of these validations. +-----------------------------------------------------------------------------*/ + if (cols > INT_MAX - 10) + pm_error("image width (%u) too large to be processed", cols); + if (rows > INT_MAX - 10) + pm_error("image height (%u) too large to be processed", rows); +} + + + static unsigned int bitpop8(unsigned char const x) { /*---------------------------------------------------------------------------- @@ -179,3 +202,6 @@ pbm_backgroundbitrow(unsigned const char * const packedBits, } return retval; } + + + |