RepoMirrors/musl
1
0
Fork 0
mirror of git://git.musl-libc.org/musl synced 2025-02-22 13:56:49 +00:00
Code Issues Packages Projects Releases Wiki Activity

fix OOB reads in Xbyte_memmem

Browse Source 
Reported by Leah Neukirchen.
This commit is contained in:
Alexander Monakov 2017-06-30 00:35:33 +03:00 committed by Rich Felker
parent cc0dbd5f09
commit 51bdcdc424
1 changed files with 9 additions and 9 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

18
src/string/memmem.c
View File

@ -5,27 +5,27 @@
static char *twobyte_memmem(const unsigned char *h, size_t k, const unsigned char *n)
{
uint16_t nw = n[0]<<8 | n[1], hw = h[0]<<8 | h[1];
for (h++, k--; k; k--, hw = hw<<8 | *++h)
if (hw == nw) return (char *)h-1;
return 0;
for (h+=2, k-=2; k; k--, hw = hw<<8 | *h++)
if (hw == nw) return (char *)h-2;
return hw == nw ? (char *)h-2 : 0;
}
static char *threebyte_memmem(const unsigned char *h, size_t k, const unsigned char *n)
{
uint32_t nw = n[0]<<24 | n[1]<<16 | n[2]<<8;
uint32_t hw = h[0]<<24 | h[1]<<16 | h[2]<<8;
for (h+=2, k-=2; k; k--, hw = (hw|*++h)<<8)
if (hw == nw) return (char *)h-2;
return 0;
for (h+=3, k-=3; k; k--, hw = (hw|*h++)<<8)
if (hw == nw) return (char *)h-3;
return hw == nw ? (char *)h-3 : 0;
}
static char *fourbyte_memmem(const unsigned char *h, size_t k, const unsigned char *n)
{
uint32_t nw = n[0]<<24 | n[1]<<16 | n[2]<<8 | n[3];
uint32_t hw = h[0]<<24 | h[1]<<16 | h[2]<<8 | h[3];
for (h+=3, k-=3; k; k--, hw = hw<<8 | *++h)
if (hw == nw) return (char *)h-3;
return 0;
for (h+=4, k-=4; k; k--, hw = hw<<8 | *h++)
if (hw == nw) return (char *)h-4;
return hw == nw ? (char *)h-4 : 0;
}
#define MAX(a,b) ((a)>(b)?(a):(b))