diff options
| -rw-r--r-- | Changes | 4 | ||||
| -rw-r--r-- | Makefile.in | 2 | ||||
| -rw-r--r-- | lzfP.h | 4 | ||||
| -rw-r--r-- | lzf_c.c | 179 |
4 files changed, 98 insertions, 91 deletions
@@ -1,3 +1,7 @@ +1.2 Mon Dec 29 13:47:28 CET 2003 + - avoid spurious memory accesses after the to-be-compressed + memory region. originally reported by Michal Zalewski. + 1.1 Tue Dec 23 05:48:32 CET 2003 - removed #warn directive, it's not worth the hassle. - add LZF_STACK_ARG and AVOID_ERRNO configurations diff --git a/Makefile.in b/Makefile.in index ef5b2d3..4aca98c 100644 --- a/Makefile.in +++ b/Makefile.in @@ -1,4 +1,4 @@ -VERSION = 1.1 +VERSION = 1.2 prefix = @prefix@ exec_prefix = @exec_prefix@ @@ -91,11 +91,11 @@ /* * Wether to pass the LZF_STATE variable as argument, or allocate it - * on the stack. For small-stack environments, define this to zero. + * on the stack. For small-stack environments, define this to 1. * NOTE: this breaks the prototype in lzf.h. */ #ifndef LZF_STATE_ARG -# define LZF_STATE_ARG 1 +# define LZF_STATE_ARG 0 #endif /*****************************************************************************/ @@ -69,12 +69,12 @@ unsigned int lzf_compress (const void *const in_data, unsigned int in_len, void *out_data, unsigned int out_len -#if !LZF_STATE_ARG +#if LZF_STATE_ARG , LZF_STATE *htab #endif ) { -#if LZF_STATE_ARG +#if !LZF_STATE_ARG LZF_STATE htab; #endif const u8 **hslot; @@ -97,107 +97,110 @@ lzf_compress (const void *const in_data, unsigned int in_len, # endif #endif - do + for (;;) { - hval = NEXT (hval, ip); - hslot = htab + IDX (hval); - ref = *hslot; *hslot = ip; + if (ip < in_end - 2) + { + hval = NEXT (hval, ip); + hslot = htab + IDX (hval); + ref = *hslot; *hslot = ip; - if (1 + if (1 #if INIT_HTAB && !USE_MEMCPY - && ref < ip /* the next test will actually take care of this, but it is faster */ + && ref < ip /* the next test will actually take care of this, but this is faster */ #endif - && (off = ip - ref - 1) < MAX_OFF - && ip + 4 < in_end - && ref > (u8 *)in_data + && (off = ip - ref - 1) < MAX_OFF + && ip + 4 < in_end + && ref > (u8 *)in_data #if STRICT_ALIGN - && ref[0] == ip[0] - && ref[1] == ip[1] - && ref[2] == ip[2] + && ref[0] == ip[0] + && ref[1] == ip[1] + && ref[2] == ip[2] #else - && *(u16 *)ref == *(u16 *)ip - && ref[2] == ip[2] + && *(u16 *)ref == *(u16 *)ip + && ref[2] == ip[2] #endif - ) - { - /* match found at *ref++ */ - unsigned int len = 2; - unsigned int maxlen = in_end - ip - len; - maxlen = maxlen > MAX_REF ? MAX_REF : maxlen; - - do - len++; - while (len < maxlen && ref[len] == ip[len]); - - if (op + lit + 1 + 3 >= out_end) - return 0; - - if (lit) - { - *op++ = lit - 1; - lit = -lit; - do - *op++ = ip[lit]; - while (++lit); - } - - len -= 2; - ip++; - - if (len < 7) - { - *op++ = (off >> 8) + (len << 5); - } - else - { - *op++ = (off >> 8) + ( 7 << 5); - *op++ = len - 7; - } - - *op++ = off; + ) + { + /* match found at *ref++ */ + unsigned int len = 2; + unsigned int maxlen = in_end - ip - len; + maxlen = maxlen > MAX_REF ? MAX_REF : maxlen; + + do + len++; + while (len < maxlen && ref[len] == ip[len]); + + if (op + lit + 1 + 3 >= out_end) + return 0; + + if (lit) + { + *op++ = lit - 1; + lit = -lit; + do + *op++ = ip[lit]; + while (++lit); + } + + len -= 2; + ip++; + + if (len < 7) + { + *op++ = (off >> 8) + (len << 5); + } + else + { + *op++ = (off >> 8) + ( 7 << 5); + *op++ = len - 7; + } + + *op++ = off; #if ULTRA_FAST - ip += len; - hval = FRST (ip); - hval = NEXT (hval, ip); - htab[IDX (hval)] = ip; - ip++; + ip += len; + hval = FRST (ip); + hval = NEXT (hval, ip); + htab[IDX (hval)] = ip; + ip++; #else - do - { - hval = NEXT (hval, ip); - htab[IDX (hval)] = ip; - ip++; - } - while (len--); + do + { + hval = NEXT (hval, ip); + htab[IDX (hval)] = ip; + ip++; + } + while (len--); #endif - } - else - { - /* one more literal byte we must copy */ - lit++; - ip++; - - if (lit == MAX_LIT) - { - if (op + 1 + MAX_LIT >= out_end) - return 0; - - *op++ = MAX_LIT - 1; + continue; + } + } + else if (ip == in_end) + break; + + /* one more literal byte we must copy */ + lit++; + ip++; + + if (lit == MAX_LIT) + { + if (op + 1 + MAX_LIT >= out_end) + return 0; + + *op++ = MAX_LIT - 1; #if USE_MEMCPY - memcpy (op, ip - MAX_LIT, MAX_LIT); - op += MAX_LIT; - lit = 0; + memcpy (op, ip - MAX_LIT, MAX_LIT); + op += MAX_LIT; + lit = 0; #else - lit = -lit; - do - *op++ = ip[lit]; - while (++lit); + lit = -lit; + do + *op++ = ip[lit]; + while (++lit); #endif - } - } + } } - while (ip < in_end); if (lit) { |