Protect against overflow of ltree.numlevel and lquery.numlevel.

These uint16 fields could be overflowed by excessively long input,
producing strange results.  Complain for invalid input.

Likewise check for out-of-range values of the repeat counts in lquery.
(We don't try too hard on that one, notably not bothering to detect
if atoi's result has overflowed.)

Also detect length overflow in ltree_concat.

In passing, be more consistent about whether "syntax error" messages
include the type name.  Also, clarify the documentation about what
the size limit is.

This has been broken for a long time, so back-patch to all supported
branches.

Nikita Glukhov, reviewed by Benjie Gillam and Tomas Vondra

Discussion: https://postgr.es/m/CAP_rww=waX2Oo6q+MbMSiZ9ktdj6eaJj0cQzNu=Ry2cCDij5fw@mail.gmail.com

diff --git a/contrib/ltree/expected/ltree.out b/contrib/ltree/expected/ltree.out
index 822693090567919f9ac453377594c93326eb571d..41e7f947875b7e7ca990c799b9e2639956a00409 100644 (file)
--- a/contrib/ltree/expected/ltree.out
+++ b/contrib/ltree/expected/ltree.out
@@ -457,6 +457,52 @@ SELECT nlevel('1.2.3.4');
       4
 (1 row)
 
+SELECT nlevel(('1' || repeat('.1', 65534))::ltree);
+ nlevel 
+--------
+  65535
+(1 row)
+
+SELECT nlevel(('1' || repeat('.1', 65535))::ltree);
+ERROR:  number of ltree levels (65536) exceeds the maximum allowed (65535)
+SELECT nlevel(('1' || repeat('.1', 65534))::ltree || '1');
+ERROR:  number of ltree levels (65536) exceeds the maximum allowed (65535)
+SELECT ('1' || repeat('.1', 65534))::lquery IS NULL;
+ ?column? 
+----------
+ f
+(1 row)
+
+SELECT ('1' || repeat('.1', 65535))::lquery IS NULL;
+ERROR:  number of lquery levels (65536) exceeds the maximum allowed (65535)
+SELECT '*{65535}'::lquery;
+  lquery  
+----------
+ *{65535}
+(1 row)
+
+SELECT '*{65536}'::lquery;
+ERROR:  lquery syntax error
+LINE 1: SELECT '*{65536}'::lquery;
+               ^
+DETAIL:  Low limit (65536) exceeds the maximum allowed (65535).
+SELECT '*{,65534}'::lquery;
+  lquery   
+-----------
+ *{,65534}
+(1 row)
+
+SELECT '*{,65535}'::lquery;
+ lquery 
+--------
+ *
+(1 row)
+
+SELECT '*{,65536}'::lquery;
+ERROR:  lquery syntax error
+LINE 1: SELECT '*{,65536}'::lquery;
+               ^
+DETAIL:  High limit (65536) exceeds the maximum allowed (65535).
 SELECT '1.2'::ltree  < '2.2'::ltree;
  ?column? 
 ----------

diff --git a/contrib/ltree/ltree.h b/contrib/ltree/ltree.h
index 366e58004c7243db557a266e80dede26d681e9dd..a5608ca1f6dee7c49715197d68fd4daffd4f14f2 100644 (file)
--- a/contrib/ltree/ltree.h
+++ b/contrib/ltree/ltree.h
@@ -25,6 +25,7 @@ typedef struct
 
 #define LTREE_HDRSIZE  MAXALIGN( offsetof(ltree, data) )
 #define LTREE_FIRST(x) ( (ltree_level*)( ((char*)(x))+LTREE_HDRSIZE ) )
+#define LTREE_MAX_LEVELS   PG_UINT16_MAX   /* ltree.numlevel is uint16 */
 
 
 /* lquery */
@@ -77,6 +78,7 @@ typedef struct
 
 #define LQUERY_HDRSIZE  MAXALIGN( offsetof(lquery, data) )
 #define LQUERY_FIRST(x)   ( (lquery_level*)( ((char*)(x))+LQUERY_HDRSIZE ) )
+#define LQUERY_MAX_LEVELS  PG_UINT16_MAX   /* lquery.numlevel is uint16 */
 
 #define LQUERY_HASNOT      0x01
 

diff --git a/contrib/ltree/ltree_io.c b/contrib/ltree/ltree_io.c
index 900a46a9e7d072905697f692e79c6f957bdee50f..3ae7dc0d069dd12536c0680ea0c38b9aa02e5f5b 100644 (file)
--- a/contrib/ltree/ltree_io.c
+++ b/contrib/ltree/ltree_io.c
@@ -58,11 +58,11 @@ ltree_in(PG_FUNCTION_ARGS)
        ptr += charlen;
    }
 
-   if (num + 1 > MaxAllocSize / sizeof(nodeitem))
+   if (num + 1 > LTREE_MAX_LEVELS)
        ereport(ERROR,
                (errcode(ERRCODE_PROGRAM_LIMIT_EXCEEDED),
-                errmsg("number of levels (%d) exceeds the maximum allowed (%d)",
-                       num + 1, (int) (MaxAllocSize / sizeof(nodeitem)))));
+                errmsg("number of ltree levels (%d) exceeds the maximum allowed (%d)",
+                       num + 1, LTREE_MAX_LEVELS)));
    list = lptr = (nodeitem *) palloc(sizeof(nodeitem) * (num + 1));
    ptr = buf;
    while (*ptr)
@@ -227,11 +227,11 @@ lquery_in(PG_FUNCTION_ARGS)
    }
 
    num++;
-   if (num > MaxAllocSize / ITEMSIZE)
+   if (num > LQUERY_MAX_LEVELS)
        ereport(ERROR,
                (errcode(ERRCODE_PROGRAM_LIMIT_EXCEEDED),
-                errmsg("number of levels (%d) exceeds the maximum allowed (%d)",
-                       num, (int) (MaxAllocSize / ITEMSIZE))));
+                errmsg("number of lquery levels (%d) exceeds the maximum allowed (%d)",
+                       num, LQUERY_MAX_LEVELS)));
    curqlevel = tmpql = (lquery_level *) palloc0(ITEMSIZE * num);
    ptr = buf;
    while (*ptr)
@@ -344,7 +344,7 @@ lquery_in(PG_FUNCTION_ARGS)
            else if (charlen == 1 && t_iseq(ptr, '.'))
            {
                curqlevel->low = 0;
-               curqlevel->high = 0xffff;
+               curqlevel->high = LTREE_MAX_LEVELS;
                curqlevel = NEXTLEV(curqlevel);
                state = LQPRS_WAITLEVEL;
            }
@@ -357,7 +357,16 @@ lquery_in(PG_FUNCTION_ARGS)
                state = LQPRS_WAITSNUM;
            else if (t_isdigit(ptr))
            {
-               curqlevel->low = atoi(ptr);
+               int         low = atoi(ptr);
+
+               if (low < 0 || low > LTREE_MAX_LEVELS)
+                   ereport(ERROR,
+                           (errcode(ERRCODE_SYNTAX_ERROR),
+                            errmsg("lquery syntax error"),
+                            errdetail("Low limit (%d) exceeds the maximum allowed (%d).",
+                                      low, LTREE_MAX_LEVELS)));
+
+               curqlevel->low = (uint16) low;
                state = LQPRS_WAITND;
            }
            else
@@ -367,12 +376,21 @@ lquery_in(PG_FUNCTION_ARGS)
        {
            if (t_isdigit(ptr))
            {
-               curqlevel->high = atoi(ptr);
+               int         high = atoi(ptr);
+
+               if (high < 0 || high > LTREE_MAX_LEVELS)
+                   ereport(ERROR,
+                           (errcode(ERRCODE_SYNTAX_ERROR),
+                            errmsg("lquery syntax error"),
+                            errdetail("High limit (%d) exceeds the maximum allowed (%d).",
+                                      high, LTREE_MAX_LEVELS)));
+
+               curqlevel->high = (uint16) high;
                state = LQPRS_WAITCLOSE;
            }
            else if (charlen == 1 && t_iseq(ptr, '}'))
            {
-               curqlevel->high = 0xffff;
+               curqlevel->high = LTREE_MAX_LEVELS;
                state = LQPRS_WAITEND;
            }
            else
@@ -422,7 +440,7 @@ lquery_in(PG_FUNCTION_ARGS)
        if (lptr->start == ptr)
            ereport(ERROR,
                    (errcode(ERRCODE_SYNTAX_ERROR),
-                    errmsg("syntax error"),
+                    errmsg("lquery syntax error"),
                     errdetail("Unexpected end of line.")));
 
        lptr->len = ptr - lptr->start -
@@ -432,7 +450,7 @@ lquery_in(PG_FUNCTION_ARGS)
        if (lptr->len == 0)
            ereport(ERROR,
                    (errcode(ERRCODE_SYNTAX_ERROR),
-                    errmsg("syntax error"),
+                    errmsg("lquery syntax error"),
                     errdetail("Unexpected end of line.")));
 
        if (lptr->wlen > 255)
@@ -444,11 +462,11 @@ lquery_in(PG_FUNCTION_ARGS)
                               lptr->wlen, pos)));
    }
    else if (state == LQPRS_WAITOPEN)
-       curqlevel->high = 0xffff;
+       curqlevel->high = LTREE_MAX_LEVELS;
    else if (state != LQPRS_WAITEND)
        ereport(ERROR,
                (errcode(ERRCODE_SYNTAX_ERROR),
-                errmsg("syntax error"),
+                errmsg("lquery syntax error"),
                 errdetail("Unexpected end of line.")));
 
    curqlevel = tmpql;
@@ -468,8 +486,8 @@ lquery_in(PG_FUNCTION_ARGS)
        else if (curqlevel->low > curqlevel->high)
            ereport(ERROR,
                    (errcode(ERRCODE_SYNTAX_ERROR),
-                    errmsg("syntax error"),
-                    errdetail("Low limit(%d) is greater than upper(%d).",
+                    errmsg("lquery syntax error"),
+                    errdetail("Low limit (%d) is greater than upper (%d).",
                               curqlevel->low, curqlevel->high)));
 
        curqlevel = NEXTLEV(curqlevel);
@@ -593,7 +611,7 @@ lquery_out(PG_FUNCTION_ARGS)
            }
            else if (curqlevel->low == 0)
            {
-               if (curqlevel->high == 0xffff)
+               if (curqlevel->high == LTREE_MAX_LEVELS)
                {
                    *ptr = '*';
                    *(ptr + 1) = '\0';
@@ -601,7 +619,7 @@ lquery_out(PG_FUNCTION_ARGS)
                else
                    sprintf(ptr, "*{,%d}", curqlevel->high);
            }
-           else if (curqlevel->high == 0xffff)
+           else if (curqlevel->high == LTREE_MAX_LEVELS)
            {
                sprintf(ptr, "*{%d,}", curqlevel->low);
            }

diff --git a/contrib/ltree/ltree_op.c b/contrib/ltree/ltree_op.c
index 070868f25af9577d80145b7fa7fecda00c7b4cc3..34e6e4b2aaa81c925ff77f60541b182d30b72652 100644 (file)
--- a/contrib/ltree/ltree_op.c
+++ b/contrib/ltree/ltree_op.c
@@ -274,10 +274,17 @@ static ltree *
 ltree_concat(ltree *a, ltree *b)
 {
    ltree      *r;
+   int         numlevel = (int) a->numlevel + b->numlevel;
+
+   if (numlevel > LTREE_MAX_LEVELS)
+       ereport(ERROR,
+               (errcode(ERRCODE_PROGRAM_LIMIT_EXCEEDED),
+                errmsg("number of ltree levels (%d) exceeds the maximum allowed (%d)",
+                       numlevel, LTREE_MAX_LEVELS)));
 
    r = (ltree *) palloc0(VARSIZE(a) + VARSIZE(b) - LTREE_HDRSIZE);
    SET_VARSIZE(r, VARSIZE(a) + VARSIZE(b) - LTREE_HDRSIZE);
-   r->numlevel = a->numlevel + b->numlevel;
+   r->numlevel = (uint16) numlevel;
 
    memcpy(LTREE_FIRST(r), LTREE_FIRST(a), VARSIZE(a) - LTREE_HDRSIZE);
    memcpy(((char *) LTREE_FIRST(r)) + VARSIZE(a) - LTREE_HDRSIZE,

diff --git a/contrib/ltree/sql/ltree.sql b/contrib/ltree/sql/ltree.sql
index 846b04e48eefbec141eadadf959b07f94ccecb6f..fca3ae645d24a1b95fd0ab96a202a09be79bacf1 100644 (file)
--- a/contrib/ltree/sql/ltree.sql
+++ b/contrib/ltree/sql/ltree.sql
@@ -90,6 +90,17 @@ SELECT '1.*.4|3|2.*{1}'::lquery;
 SELECT 'qwerty%@*.tu'::lquery;
 
 SELECT nlevel('1.2.3.4');
+SELECT nlevel(('1' || repeat('.1', 65534))::ltree);
+SELECT nlevel(('1' || repeat('.1', 65535))::ltree);
+SELECT nlevel(('1' || repeat('.1', 65534))::ltree || '1');
+SELECT ('1' || repeat('.1', 65534))::lquery IS NULL;
+SELECT ('1' || repeat('.1', 65535))::lquery IS NULL;
+SELECT '*{65535}'::lquery;
+SELECT '*{65536}'::lquery;
+SELECT '*{,65534}'::lquery;
+SELECT '*{,65535}'::lquery;
+SELECT '*{,65536}'::lquery;
+
 SELECT '1.2'::ltree  < '2.2'::ltree;
 SELECT '1.2'::ltree  <= '2.2'::ltree;
 SELECT '2.2'::ltree  = '2.2'::ltree;

diff --git a/doc/src/sgml/ltree.sgml b/doc/src/sgml/ltree.sgml
index b4e07f651097392f6f4420a902275203637178c0..0c74aa705e964804712a10ac0258a54f725fbc7a 100644 (file)
--- a/doc/src/sgml/ltree.sgml
+++ b/doc/src/sgml/ltree.sgml
@@ -37,8 +37,7 @@
    A <firstterm>label path</firstterm> is a sequence of zero or more
    labels separated by dots, for example <literal>L1.L2.L3</literal>, representing
    a path from the root of a hierarchical tree to a particular node.  The
-   length of a label path must be less than 65kB, but keeping it under 2kB is
-   preferable.
+   length of a label path cannot exceed 65535 labels.
   </para>
 
   <para>