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ppd-ipp.c: Prevent stack buffer overflow on >20-item PPD attributes #108

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Merged
tillkamppeter merged 1 commit into from
Nov 14, 2026
Merged

ppd-ipp.c: Prevent stack buffer overflow on >20-item PPD attributes #108

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5 changes: 4 additions & 1 deletion ppd/ppd-ipp.c
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Original file line number Diff line number Diff line change
Expand Up @@ -612,8 +612,11 @@ ppdLoadAttributes(
{
// Convert PPD-style names into IPP-style names
ppdPwgUnppdizeName(ppd_attr->name + 4, item_buf, sizeof(item_buf), NULL);
if (!ppd_attr->value)
continue;
// Make array from comma-separated list
strncpy(buf, ppd_attr->value, sizeof(buf) - 1);
buf[sizeof(buf) - 1] = '\0';
num_items = 0;
char *p = buf;
do
Expand All @@ -633,7 +636,7 @@ ppdLoadAttributes(
items[num_items - 1][0] == 'R' && items[num_items - 1][1] == 'S')
xres = yres = atoi(items[num_items - 1] + 2);
}
while (p);
while (p && num_items < (int)(sizeof(items) / sizeof(items[0])));
if (strlen(items[0]) > 3 &&
strncasecmp(items[0] + strlen(items[0]) - 3, "dpi", 3) == 0 &&
isdigit(*(items[0] + strlen(items[0]) - 4)))
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23 changes: 23 additions & 0 deletions ppd/test_ppd_ipp.c
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Original file line number Diff line number Diff line change
Expand Up @@ -1002,6 +1002,29 @@ main(void)
ippDelete(job_attrs);


// T70 — 21-item comma-separated raster attribute must not overflow items[20]
// in ppdLoadAttributes() (Issue #85).
testBegin("ppdLoadAttributes(21-item cupsPwgRaster attribute) caps at 20 items");
{
FILE *f21 = tmpfile();
fputs(test_ppd_text, f21);
fputs("*cupsFilter: \"image/pwg-raster 0 rastertopwg\"\n"
"*cupsPwgRasterAuditSupported: \"v1,v2,v3,v4,v5,v6,v7,v8,v9,v10,"
"v11,v12,v13,v14,v15,v16,v17,v18,v19,v20,v21\"\n", f21);
rewind(f21);
ppd_file_t *ppd21 = ppdOpen(f21);
fclose(f21);
ipp_t *attrs21 = ppdLoadAttributes(ppd21);
ipp_attribute_t *audit_attr = ippFindAttribute(attrs21,
"pwg-raster-audit-supported",
IPP_TAG_KEYWORD);
int count = audit_attr ? ippGetCount(audit_attr) : -1;
testEndMessage(attrs21 != NULL && count == 20, "count=%d", count);
ippDelete(attrs21);
ppdClose(ppd21);
}


// =========================================================================
// Cleanup
// =========================================================================
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