diff options
Diffstat (limited to 'src/backend/utils/adt/arrayutils.c')
| -rw-r--r-- | src/backend/utils/adt/arrayutils.c | 31 |
1 files changed, 31 insertions, 0 deletions
diff --git a/src/backend/utils/adt/arrayutils.c b/src/backend/utils/adt/arrayutils.c index 2a6a05718f8..6988edd9361 100644 --- a/src/backend/utils/adt/arrayutils.c +++ b/src/backend/utils/adt/arrayutils.c @@ -16,6 +16,7 @@ #include "postgres.h" #include "catalog/pg_type.h" +#include "common/int.h" #include "utils/array.h" #include "utils/builtins.h" #include "utils/memutils.h" @@ -112,6 +113,36 @@ ArrayGetNItems(int ndim, const int *dims) } /* + * Verify sanity of proposed lower-bound values for an array + * + * The lower-bound values must not be so large as to cause overflow when + * calculating subscripts, e.g. lower bound 2147483640 with length 10 + * must be disallowed. We actually insist that dims[i] + lb[i] be + * computable without overflow, meaning that an array with last subscript + * equal to INT_MAX will be disallowed. + * + * It is assumed that the caller already called ArrayGetNItems, so that + * overflowed (negative) dims[] values have been eliminated. + */ +void +ArrayCheckBounds(int ndim, const int *dims, const int *lb) +{ + int i; + + for (i = 0; i < ndim; i++) + { + /* PG_USED_FOR_ASSERTS_ONLY prevents variable-isn't-read warnings */ + int32 sum PG_USED_FOR_ASSERTS_ONLY; + + if (pg_add_s32_overflow(dims[i], lb[i], &sum)) + ereport(ERROR, + (errcode(ERRCODE_PROGRAM_LIMIT_EXCEEDED), + errmsg("array lower bound is too large: %d", + lb[i]))); + } +} + +/* * Compute ranges (sub-array dimensions) for an array slice * * We assume caller has validated slice endpoints, so overflow is impossible |