diff options
| -rw-r--r-- | source3/lib/util.c | 18 | ||||
| -rw-r--r-- | source3/smbd/lanman.c | 18 |
2 files changed, 29 insertions, 7 deletions
diff --git a/source3/lib/util.c b/source3/lib/util.c index 64afa1cc53..b1db36c250 100644 --- a/source3/lib/util.c +++ b/source3/lib/util.c @@ -3127,6 +3127,8 @@ int this_is_smp(void) /**************************************************************** Check if an offset into a buffer is safe. + If this returns True it's safe to indirect into the byte at + pointer ptr+off. ****************************************************************/ BOOL is_offset_safe(const char *buf_base, size_t buf_len, char *ptr, size_t off) @@ -3180,10 +3182,14 @@ char *get_safe_str_ptr(const char *buf_base, size_t buf_len, char *ptr, size_t o int get_safe_SVAL(const char *buf_base, size_t buf_len, char *ptr, size_t off, int failval) { - if (!is_offset_safe(buf_base, buf_len, ptr, off+2)) { + /* + * Note we use off+1 here, not off+2 as SVAL accesses ptr[0] and ptr[1], + * NOT ptr[2]. + */ + if (!is_offset_safe(buf_base, buf_len, ptr, off+1)) { return failval; } - return SVAL(ptr,0); + return SVAL(ptr,off); } /**************************************************************** @@ -3192,8 +3198,12 @@ int get_safe_SVAL(const char *buf_base, size_t buf_len, char *ptr, size_t off, i int get_safe_IVAL(const char *buf_base, size_t buf_len, char *ptr, size_t off, int failval) { - if (!is_offset_safe(buf_base, buf_len, ptr, off+4)) { + /* + * Note we use off+3 here, not off+4 as IVAL accesses + * ptr[0] ptr[1] ptr[2] ptr[3] NOT ptr[4]. + */ + if (!is_offset_safe(buf_base, buf_len, ptr, off+3)) { return failval; } - return IVAL(ptr,0); + return IVAL(ptr,off); } diff --git a/source3/smbd/lanman.c b/source3/smbd/lanman.c index 0ef6fe1c47..4ca9a4b051 100644 --- a/source3/smbd/lanman.c +++ b/source3/smbd/lanman.c @@ -2365,7 +2365,11 @@ static BOOL api_SetUserPassword(connection_struct *conn,uint16 vuid, memset(pass1,'\0',sizeof(pass1)); memset(pass2,'\0',sizeof(pass2)); - if (!is_offset_safe(param,tpscnt,p,32)) { + /* + * We use 31 here not 32 as we're checking + * the last byte we want to access is safe. + */ + if (!is_offset_safe(param,tpscnt,p,31)) { return False; } memcpy(pass1,p,16); @@ -2537,7 +2541,11 @@ static BOOL api_RDosPrintJobDel(connection_struct *conn,uint16 vuid, if (!str1 || !str2 || !p) { return False; } - if (!is_offset_safe(param,tpscnt,p,2)) { + /* + * We use 1 here not 2 as we're checking + * the last byte we want to access is safe. + */ + if (!is_offset_safe(param,tpscnt,p,1)) { return False; } if(!rap_to_pjobid(SVAL(p,0), sharename, &jobid)) @@ -2701,7 +2709,11 @@ static BOOL api_PrintJobInfo(connection_struct *conn, uint16 vuid, if (!str1 || !str2 || !p) { return False; } - if (!is_offset_safe(param,tpscnt,p,2)) { + /* + * We use 1 here not 2 as we're checking + * the last byte we want to access is safe. + */ + if (!is_offset_safe(param,tpscnt,p,1)) { return False; } if(!rap_to_pjobid(SVAL(p,0), sharename, &jobid)) |