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 fd86323ffe0b6625216149685e66b9edbeab665e..5230f90415f5a2f20a78c1e4bc69927857b093fe 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 34ca597a484cbc495e78679ffdeaea1cabcf817e..2cd219a2302b4f6d8b051d5e5381fd88917484ae 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 d1067f8146567beee33990fa7f3b2ee85d3115de..6c7269cc8a2a36c6653e560dbe80acdb49e2e9de 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 77599adeafd2f6fc2612a9466f5beddea23986b0..97dc8aa2d06abc13029904045c69ea848ce61636 100644 (file)
--- a/doc/src/sgml/ltree.sgml
+++ b/doc/src/sgml/ltree.sgml
@@ -31,8 +31,7 @@
    A <firstterm>label path</firstterm> is a sequence of zero or more
    labels separated by dots, for example <literal>L1.L2.L3</>, 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>