osmith
/
wireshark
forked from osmocom/wireshark
1
0
Fork 0
Code Pull Requests Releases Wiki Activity

dfilter: Fix a crash using abs() 

Passing a literal value to abs() on the LHS segfaults, because it
is incorrectly assumed to be a valid field.

We need to check if we actually have a field. While at it improve
the diagnostic of literals.
This commit is contained in:
João Valverde 2022-07-19 19:08:31 +01:00
parent 9e84721c1a
commit 84f54d54e5
1 changed files with 14 additions and 5 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

19
epan/dfilter/dfunctions.c
View File

@ -408,17 +408,26 @@ ul_semcheck_absolute_value(dfwork_t *dfw, const char *func_name, ftenum_t lhs_ft
if (stnode_type_id(st_node) == STTYPE_ARITHMETIC) {
ftype = check_arithmetic_expr(dfw, st_node, lhs_ftype);
}
else if (stnode_type_id(st_node) == STTYPE_LITERAL && lhs_ftype != FT_NONE) {
fv = dfilter_fvalue_from_literal(dfw, lhs_ftype, st_node, FALSE, NULL);
stnode_replace(st_node, STTYPE_FVALUE, fv);
ftype = fvalue_type_ftenum(fv);
else if (stnode_type_id(st_node) == STTYPE_LITERAL) {
if (lhs_ftype != FT_NONE) {
/* Convert RHS literal to the same ftype as LHS. */
fv = dfilter_fvalue_from_literal(dfw, lhs_ftype, st_node, FALSE, NULL);
stnode_replace(st_node, STTYPE_FVALUE, fv);
ftype = fvalue_type_ftenum(fv);
}
else {
FAIL(dfw, st_node, "Need a field or field-like value on the LHS.");
}
}
else if (stnode_type_id(st_node) == STTYPE_FUNCTION) {
ftype = check_function(dfw, st_node, lhs_ftype);
}
else {
else if (stnode_type_id(st_node) == STTYPE_FIELD) {
ftype = sttype_field_ftenum(st_node);
}
else {
ftype = FT_NONE;
}
if (ftype == FT_NONE) {
FAIL(dfw, st_node, "Type %s is not valid for %s",