| |
| /*--------------------------------------------------------------------*/ |
| /*--- Replacements for strcpy(), memcpy() et al, which run on the ---*/ |
| /*--- simulated CPU. ---*/ |
| /*--- mac_replace_strmem.c ---*/ |
| /*--------------------------------------------------------------------*/ |
| |
| /* |
| This file is part of MemCheck, a heavyweight Valgrind tool for |
| detecting memory errors. |
| |
| Copyright (C) 2000-2005 Julian Seward |
| jseward@acm.org |
| |
| This program is free software; you can redistribute it and/or |
| modify it under the terms of the GNU General Public License as |
| published by the Free Software Foundation; either version 2 of the |
| License, or (at your option) any later version. |
| |
| This program is distributed in the hope that it will be useful, but |
| WITHOUT ANY WARRANTY; without even the implied warranty of |
| MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| General Public License for more details. |
| |
| You should have received a copy of the GNU General Public License |
| along with this program; if not, write to the Free Software |
| Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA |
| 02111-1307, USA. |
| |
| The GNU General Public License is contained in the file COPYING. |
| */ |
| |
| #include "mc_include.h" |
| #include "memcheck.h" |
| #include "valgrind.h" |
| #include "pub_tool_redir.h" |
| |
| /* --------------------------------------------------------------------- |
| We have our own versions of these functions for two reasons: |
| (a) it allows us to do overlap checking |
| (b) some of the normal versions are hyper-optimised, which fools |
| Memcheck and cause spurious value warnings. Our versions are |
| simpler. |
| |
| Note that overenthusiastic use of PLT bypassing by the glibc people also |
| means that we need to patch multiple versions of some of the functions to |
| our own implementations. |
| |
| THEY RUN ON THE SIMD CPU! |
| ------------------------------------------------------------------ */ |
| |
| /* Figure out if [dst .. dst+dstlen-1] overlaps with |
| [src .. src+srclen-1]. |
| We assume that the address ranges do not wrap around |
| (which is safe since on Linux addresses >= 0xC0000000 |
| are not accessible and the program will segfault in this |
| circumstance, presumably). |
| */ |
| static __inline__ |
| Bool is_overlap ( void* dst, const void* src, SizeT dstlen, SizeT srclen ) |
| { |
| Addr loS, hiS, loD, hiD; |
| |
| if (dstlen == 0 || srclen == 0) |
| return False; |
| |
| loS = (Addr)src; |
| loD = (Addr)dst; |
| hiS = loS + srclen - 1; |
| hiD = loD + dstlen - 1; |
| |
| /* So figure out if [loS .. hiS] overlaps with [loD .. hiD]. */ |
| if (loS < loD) { |
| return !(hiS < loD); |
| } |
| else if (loD < loS) { |
| return !(hiD < loS); |
| } |
| else { |
| /* They start at same place. Since we know neither of them has |
| zero length, they must overlap. */ |
| return True; |
| } |
| } |
| |
| // This is a macro rather than a function because we don't want to have an |
| // extra function in the stack trace. |
| #define RECORD_OVERLAP_ERROR(s, p_extra) \ |
| { \ |
| Word unused_res; \ |
| VALGRIND_MAGIC_SEQUENCE(unused_res, 0, \ |
| _VG_USERREQ__MEMCHECK_RECORD_OVERLAP_ERROR, \ |
| s, p_extra, 0, 0); \ |
| } |
| |
| static __inline__ |
| void complain2 ( Char* s, char* dst, const char* src ) |
| { |
| OverlapExtra extra = { |
| .src = (Addr)src, .dst = (Addr)dst, .len = -1, |
| }; |
| RECORD_OVERLAP_ERROR( s, &extra ); |
| } |
| |
| static __inline__ |
| void complain3 ( Char* s, void* dst, const void* src, int n ) |
| { |
| /* Must wrap it up here, because we cannot pass 4 args to core */ |
| OverlapExtra extra = { |
| .src = (Addr)src, .dst = (Addr)dst, .len = n, |
| }; |
| RECORD_OVERLAP_ERROR( s, &extra ); |
| } |
| |
| // Some handy Z-encoded names |
| #define m_libc_so_6 libcZdsoZd6 // libc.so.6 |
| #define m_ld_linux_so_2 ldZhlinuxZdsoZd2 // ld-linux.so.2 |
| #define m_ld_linux_x86_64_so_2 ldZhlinuxZhx86Zh64ZdsoZd2 // ld-linux-x86-64.so.2 |
| |
| |
| #define STRRCHR(soname, fnname) \ |
| char* VG_REPLACE_FUNCTION(soname,fnname)( const char* s, int c ); \ |
| char* VG_REPLACE_FUNCTION(soname,fnname)( const char* s, int c ) \ |
| { \ |
| UChar ch = (UChar)((UInt)c); \ |
| UChar* p = (UChar*)s; \ |
| UChar* last = NULL; \ |
| while (True) { \ |
| if (*p == ch) last = p; \ |
| if (*p == 0) return last; \ |
| p++; \ |
| } \ |
| } |
| |
| // Apparently rindex() is the same thing as strrchr() |
| STRRCHR(m_libc_so_6, strrchr) |
| STRRCHR(m_libc_so_6, rindex) |
| STRRCHR(m_ld_linux_so_2, rindex) |
| |
| |
| #define STRCHR(soname, fnname) \ |
| char* VG_REPLACE_FUNCTION(soname,fnname) ( const char* s, int c ); \ |
| char* VG_REPLACE_FUNCTION(soname,fnname) ( const char* s, int c ) \ |
| { \ |
| UChar ch = (UChar)((UInt)c); \ |
| UChar* p = (UChar*)s; \ |
| while (True) { \ |
| if (*p == ch) return p; \ |
| if (*p == 0) return NULL; \ |
| p++; \ |
| } \ |
| } |
| |
| // Apparently index() is the same thing as strchr() |
| STRCHR(m_libc_so_6, strchr) |
| STRCHR(m_ld_linux_so_2, strchr) |
| STRCHR(m_libc_so_6, index) |
| STRCHR(m_ld_linux_so_2, index) |
| STRCHR(m_ld_linux_x86_64_so_2, index) |
| |
| |
| #define STRCAT(soname, fnname) \ |
| char* VG_REPLACE_FUNCTION(soname,fnname) ( char* dst, const char* src ); \ |
| char* VG_REPLACE_FUNCTION(soname,fnname) ( char* dst, const char* src ) \ |
| { \ |
| const Char* src_orig = src; \ |
| Char* dst_orig = dst; \ |
| while (*dst) dst++; \ |
| while (*src) *dst++ = *src++; \ |
| *dst = 0; \ |
| \ |
| /* This is a bit redundant, I think; any overlap and the strcat will */ \ |
| /* go forever... or until a seg fault occurs. */ \ |
| if (is_overlap(dst_orig, \ |
| src_orig, \ |
| (Addr)dst-(Addr)dst_orig+1, \ |
| (Addr)src-(Addr)src_orig+1)) \ |
| complain2("strcat", dst_orig, src_orig); \ |
| \ |
| return dst_orig; \ |
| } |
| |
| STRCAT(m_libc_so_6, strcat) |
| |
| |
| #define STRNCAT(soname, fnname) \ |
| char* VG_REPLACE_FUNCTION(soname,fnname) ( char* dst, const char* src, SizeT n ); \ |
| char* VG_REPLACE_FUNCTION(soname,fnname) ( char* dst, const char* src, SizeT n ) \ |
| { \ |
| const Char* src_orig = src; \ |
| Char* dst_orig = dst; \ |
| SizeT m = 0; \ |
| \ |
| while (*dst) dst++; \ |
| while (m < n && *src) { m++; *dst++ = *src++; } /* concat <= n chars */ \ |
| *dst = 0; /* always add null */ \ |
| \ |
| /* This checks for overlap after copying, unavoidable without */ \ |
| /* pre-counting lengths... should be ok */ \ |
| if (is_overlap(dst_orig, \ |
| src_orig, \ |
| (Addr)dst-(Addr)dst_orig+1, \ |
| (Addr)src-(Addr)src_orig+1)) \ |
| complain3("strncat", dst_orig, src_orig, n); \ |
| \ |
| return dst_orig; \ |
| } |
| |
| STRNCAT(m_libc_so_6, strncat) |
| |
| |
| #define STRNLEN(soname, fnname) \ |
| SizeT VG_REPLACE_FUNCTION(soname,fnname) ( const char* str, SizeT n ); \ |
| SizeT VG_REPLACE_FUNCTION(soname,fnname) ( const char* str, SizeT n ) \ |
| { \ |
| SizeT i = 0; \ |
| while (i < n && str[i] != 0) i++; \ |
| return i; \ |
| } |
| |
| STRNLEN(m_libc_so_6, strnlen) |
| |
| |
| #define STRLEN(soname, fnname) \ |
| SizeT VG_REPLACE_FUNCTION(soname,fnname)( const char* str ); \ |
| SizeT VG_REPLACE_FUNCTION(soname,fnname)( const char* str ) \ |
| { \ |
| SizeT i = 0; \ |
| while (str[i] != 0) i++; \ |
| return i; \ |
| } |
| |
| STRLEN(m_libc_so_6, strlen) |
| STRLEN(m_ld_linux_so_2, strlen) |
| STRLEN(m_ld_linux_x86_64_so_2, strlen) |
| |
| |
| #define STRCPY(soname, fnname) \ |
| char* VG_REPLACE_FUNCTION(soname, fnname) ( char* dst, const char* src ); \ |
| char* VG_REPLACE_FUNCTION(soname, fnname) ( char* dst, const char* src ) \ |
| { \ |
| const Char* src_orig = src; \ |
| Char* dst_orig = dst; \ |
| \ |
| while (*src) *dst++ = *src++; \ |
| *dst = 0; \ |
| \ |
| /* This checks for overlap after copying, unavoidable without */ \ |
| /* pre-counting length... should be ok */ \ |
| if (is_overlap(dst_orig, \ |
| src_orig, \ |
| (Addr)dst-(Addr)dst_orig+1, \ |
| (Addr)src-(Addr)src_orig+1)) \ |
| complain2("strcpy", dst_orig, src_orig); \ |
| \ |
| return dst_orig; \ |
| } |
| |
| STRCPY(m_libc_so_6, strcpy) |
| |
| |
| #define STRNCPY(soname, fnname) \ |
| char* VG_REPLACE_FUNCTION(soname, fnname) ( char* dst, const char* src, SizeT n ); \ |
| char* VG_REPLACE_FUNCTION(soname, fnname) ( char* dst, const char* src, SizeT n ) \ |
| { \ |
| const Char* src_orig = src; \ |
| Char* dst_orig = dst; \ |
| SizeT m = 0; \ |
| \ |
| while (m < n && *src) { m++; *dst++ = *src++; } \ |
| /* Check for overlap after copying; all n bytes of dst are relevant, */ \ |
| /* but only m+1 bytes of src if terminator was found */ \ |
| if (is_overlap(dst_orig, src_orig, n, (m < n) ? m+1 : n)) \ |
| complain3("strncpy", dst, src, n); \ |
| while (m++ < n) *dst++ = 0; /* must pad remainder with nulls */ \ |
| \ |
| return dst_orig; \ |
| } |
| |
| STRNCPY(m_libc_so_6, strncpy) |
| |
| |
| #define STRNCMP(soname, fnname) \ |
| int VG_REPLACE_FUNCTION(soname,fnname) ( const char* s1, const char* s2, SizeT nmax ); \ |
| int VG_REPLACE_FUNCTION(soname,fnname) ( const char* s1, const char* s2, SizeT nmax ) \ |
| { \ |
| SizeT n = 0; \ |
| while (True) { \ |
| if (n >= nmax) return 0; \ |
| if (*s1 == 0 && *s2 == 0) return 0; \ |
| if (*s1 == 0) return -1; \ |
| if (*s2 == 0) return 1; \ |
| \ |
| if (*(unsigned char*)s1 < *(unsigned char*)s2) return -1; \ |
| if (*(unsigned char*)s1 > *(unsigned char*)s2) return 1; \ |
| \ |
| s1++; s2++; n++; \ |
| } \ |
| } |
| |
| STRNCMP(m_libc_so_6, strncmp) |
| |
| |
| #define STRCMP(soname, fnname) \ |
| int VG_REPLACE_FUNCTION(soname,fnname) ( const char* s1, const char* s2 ); \ |
| int VG_REPLACE_FUNCTION(soname,fnname) ( const char* s1, const char* s2 ) \ |
| { \ |
| register unsigned char c1; \ |
| register unsigned char c2; \ |
| while (True) { \ |
| c1 = *(unsigned char *)s1; \ |
| c2 = *(unsigned char *)s2; \ |
| if (c1 != c2) break; \ |
| if (c1 == 0) break; \ |
| s1++; s2++; \ |
| } \ |
| if ((unsigned char)c1 < (unsigned char)c2) return -1; \ |
| if ((unsigned char)c1 > (unsigned char)c2) return 1; \ |
| return 0; \ |
| } |
| |
| STRCMP(m_libc_so_6, strcmp) |
| STRCMP(m_ld_linux_x86_64_so_2, strcmp) |
| |
| |
| #define MEMCHR(soname, fnname) \ |
| void* VG_REPLACE_FUNCTION(soname,fnname) (const void *s, int c, SizeT n); \ |
| void* VG_REPLACE_FUNCTION(soname,fnname) (const void *s, int c, SizeT n) \ |
| { \ |
| SizeT i; \ |
| UChar c0 = (UChar)c; \ |
| UChar* p = (UChar*)s; \ |
| for (i = 0; i < n; i++) \ |
| if (p[i] == c0) return (void*)(&p[i]); \ |
| return NULL; \ |
| } |
| |
| MEMCHR(m_libc_so_6, memchr) |
| |
| |
| #define MEMCPY(soname, fnname) \ |
| void* VG_REPLACE_FUNCTION(soname,fnname)( void *dst, const void *src, SizeT len ); \ |
| void* VG_REPLACE_FUNCTION(soname,fnname)( void *dst, const void *src, SizeT len ) \ |
| { \ |
| register char *d; \ |
| register char *s; \ |
| \ |
| if (len == 0) \ |
| return dst; \ |
| \ |
| if (is_overlap(dst, src, len, len)) \ |
| complain3("memcpy", dst, src, len); \ |
| \ |
| if ( dst > src ) { \ |
| d = (char *)dst + len - 1; \ |
| s = (char *)src + len - 1; \ |
| while ( len >= 4 ) { \ |
| *d-- = *s--; \ |
| *d-- = *s--; \ |
| *d-- = *s--; \ |
| *d-- = *s--; \ |
| len -= 4; \ |
| } \ |
| while ( len-- ) { \ |
| *d-- = *s--; \ |
| } \ |
| } else if ( dst < src ) { \ |
| d = (char *)dst; \ |
| s = (char *)src; \ |
| while ( len >= 4 ) { \ |
| *d++ = *s++; \ |
| *d++ = *s++; \ |
| *d++ = *s++; \ |
| *d++ = *s++; \ |
| len -= 4; \ |
| } \ |
| while ( len-- ) { \ |
| *d++ = *s++; \ |
| } \ |
| } \ |
| return dst; \ |
| } |
| |
| MEMCPY(m_libc_so_6, memcpy) |
| |
| |
| #define MEMCMP(soname, fnname) \ |
| int VG_REPLACE_FUNCTION(soname,fnname)( const void *s1V, const void *s2V, SizeT n ); \ |
| int VG_REPLACE_FUNCTION(soname,fnname)( const void *s1V, const void *s2V, SizeT n ) \ |
| { \ |
| int res; \ |
| unsigned char a0; \ |
| unsigned char b0; \ |
| unsigned char* s1 = (unsigned char*)s1V; \ |
| unsigned char* s2 = (unsigned char*)s2V; \ |
| \ |
| while (n != 0) { \ |
| a0 = s1[0]; \ |
| b0 = s2[0]; \ |
| s1 += 1; \ |
| s2 += 1; \ |
| res = ((int)a0) - ((int)b0); \ |
| if (res != 0) \ |
| return res; \ |
| n -= 1; \ |
| } \ |
| return 0; \ |
| } |
| |
| MEMCMP(m_libc_so_6, memcmp) |
| MEMCMP(m_libc_so_6, bcmp) |
| |
| |
| /* Copy SRC to DEST, returning the address of the terminating '\0' in |
| DEST. (minor variant of strcpy) */ |
| #define STPCPY(soname, fnname) \ |
| char* VG_REPLACE_FUNCTION(soname,fnname) ( char* dst, const char* src ); \ |
| char* VG_REPLACE_FUNCTION(soname,fnname) ( char* dst, const char* src ) \ |
| { \ |
| const Char* src_orig = src; \ |
| Char* dst_orig = dst; \ |
| \ |
| while (*src) *dst++ = *src++; \ |
| *dst = 0; \ |
| \ |
| /* This checks for overlap after copying, unavoidable without */ \ |
| /* pre-counting length... should be ok */ \ |
| if (is_overlap(dst_orig, \ |
| src_orig, \ |
| (Addr)dst-(Addr)dst_orig+1, \ |
| (Addr)src-(Addr)src_orig+1)) \ |
| complain2("stpcpy", dst_orig, src_orig); \ |
| \ |
| return dst; \ |
| } |
| |
| STPCPY(m_libc_so_6, stpcpy) |
| STPCPY(m_ld_linux_so_2, stpcpy) |
| |
| |
| #define MEMSET(soname, fnname) \ |
| void* VG_REPLACE_FUNCTION(soname,fnname)(void *s, Int c, SizeT n); \ |
| void* VG_REPLACE_FUNCTION(soname,fnname)(void *s, Int c, SizeT n) \ |
| { \ |
| unsigned char *cp = s; \ |
| \ |
| while(n--) \ |
| *cp++ = c; \ |
| \ |
| return s; \ |
| } |
| |
| MEMSET(m_libc_so_6, memset) |
| |
| |
| #define MEMMOVE(soname, fnname) \ |
| void* VG_REPLACE_FUNCTION(soname,fnname)(void *dstV, const void *srcV, SizeT n); \ |
| void* VG_REPLACE_FUNCTION(soname,fnname)(void *dstV, const void *srcV, SizeT n) \ |
| { \ |
| SizeT i; \ |
| Char* dst = (Char*)dstV; \ |
| Char* src = (Char*)srcV; \ |
| if (dst < src) { \ |
| for (i = 0; i < n; i++) \ |
| dst[i] = src[i]; \ |
| } \ |
| else \ |
| if (dst > src) { \ |
| for (i = 0; i < n; i++) \ |
| dst[n-i-1] = src[n-i-1]; \ |
| } \ |
| return dst; \ |
| } |
| |
| MEMMOVE(m_libc_so_6, memmove) |
| |
| |
| /* Find the first occurrence of C in S or the final NUL byte. */ |
| #define GLIBC232_STRCHRNUL(soname, fnname) \ |
| char* VG_REPLACE_FUNCTION(soname,fnname) (const char* s, int c_in); \ |
| char* VG_REPLACE_FUNCTION(soname,fnname) (const char* s, int c_in) \ |
| { \ |
| unsigned char c = (unsigned char) c_in; \ |
| unsigned char* char_ptr = (unsigned char *)s; \ |
| while (1) { \ |
| if (*char_ptr == 0) return char_ptr; \ |
| if (*char_ptr == c) return char_ptr; \ |
| char_ptr++; \ |
| } \ |
| } |
| |
| GLIBC232_STRCHRNUL(m_libc_so_6, strchrnul) |
| |
| |
| /* Find the first occurrence of C in S. */ |
| #define GLIBC232_RAWMEMCHR(soname, fnname) \ |
| char* VG_REPLACE_FUNCTION(soname,fnname) (const char* s, int c_in); \ |
| char* VG_REPLACE_FUNCTION(soname,fnname) (const char* s, int c_in) \ |
| { \ |
| unsigned char c = (unsigned char) c_in; \ |
| unsigned char* char_ptr = (unsigned char *)s; \ |
| while (1) { \ |
| if (*char_ptr == c) return char_ptr; \ |
| char_ptr++; \ |
| } \ |
| } |
| |
| GLIBC232_RAWMEMCHR(m_libc_so_6, rawmemchr) |
| |
| |
| /*--------------------------------------------------------------------*/ |
| /*--- end ---*/ |
| /*--------------------------------------------------------------------*/ |