Add a null check on return value of CPDF_StructTree::AddPageNode().
This CL Adds a null check for |pParentElement| before usage inside
AddPageNode(). This ensures that the code handles the scenario when
AddPageNode() returns nullptr if depth is greater than
kStructTreeMaxRecursion(= 32). This CL also includes a test tagged PDF
with deeply nested tags(nested depth > 33). The file is used to validate
if struct tree is loaded for this file.
Bug: pdfium:1480
Change-Id: I66c561d6708f8d89a0616eb7adef8459ae952662
Reviewed-on: https://pdfium-review.googlesource.com/c/pdfium/+/66110
Reviewed-by: Lei Zhang <thestig@chromium.org>
Commit-Queue: Mansi Awasthi <maawas@microsoft.com>
diff --git a/core/fpdfdoc/cpdf_structtree.cpp b/core/fpdfdoc/cpdf_structtree.cpp
index 8fd43e2..4976d43 100644
--- a/core/fpdfdoc/cpdf_structtree.cpp
+++ b/core/fpdfdoc/cpdf_structtree.cpp
@@ -105,6 +105,9 @@
RetainPtr<CPDF_StructElement> pParentElement =
AddPageNode(pParent, map, nLevel + 1);
+ if (!pParentElement)
+ return pElement;
+
bool bSave = false;
for (CPDF_StructKid& kid : *pParentElement->GetKids()) {
if (kid.m_Type == CPDF_StructKid::kElement && kid.m_pDict == pDict) {
diff --git a/fpdfsdk/fpdf_structtree_embeddertest.cpp b/fpdfsdk/fpdf_structtree_embeddertest.cpp
index bbaa115..21cbffd 100644
--- a/fpdfsdk/fpdf_structtree_embeddertest.cpp
+++ b/fpdfsdk/fpdf_structtree_embeddertest.cpp
@@ -177,3 +177,16 @@
UnloadPage(page);
}
+
+TEST_F(FPDFStructTreeEmbedderTest, GetStructTreeForNestedTaggedPDF) {
+ ASSERT_TRUE(OpenDocument("tagged_nested.pdf"));
+ FPDF_PAGE page = LoadPage(0);
+ ASSERT_TRUE(page);
+
+ {
+ // This call should not crash. https://crbug.com/pdfium/1480
+ ScopedFPDFStructTree struct_tree(FPDF_StructTree_GetForPage(page));
+ ASSERT_TRUE(struct_tree);
+ }
+ UnloadPage(page);
+}
diff --git a/testing/resources/tagged_nested.in b/testing/resources/tagged_nested.in
new file mode 100644
index 0000000..b7d2022
--- /dev/null
+++ b/testing/resources/tagged_nested.in
@@ -0,0 +1,346 @@
+{{header}}
+{{object 1 0}} <<
+ /Type /Catalog
+ /Pages 2 0 R
+ /StructTreeRoot 5 0 R
+ /Lang (en-US)
+ /MarkInfo <<
+ /Marked true
+ >>
+>>
+endobj
+{{object 2 0}} <<
+ /Type /Pages
+ /Count 1
+ /Kids [3 0 R]
+>>
+endobj
+{{object 3 0}} <<
+ /Type /Page
+ /Parent 2 0 R
+ /Contents 4 0 R
+ /MediaBox [0 0 612 792]
+ /StructParents 0
+>>
+endobj
+{{object 4 0}} <<
+ {{streamlen}}
+>>
+stream
+BT
+/Para<</MCID 0>>
+BMC
+0 0 Td
+/F1 18 Tf
+(Sample Text) Tj
+EMC
+ET
+endstream
+endobj
+{{object 5 0}} <<
+ /Type /StructTreeRoot
+ /ParentTree 6 0 R
+ /K [8 0 R]
+ /RoleMap <<
+ /Document /Document
+ /Para /Para
+ >>
+>>
+endobj
+{{object 6 0}} <<
+ /Nums [0 [7 0 R]]
+>>
+endobj
+{{object 7 0}} <<
+ /Type /StructElem
+ /S /Para
+ /K [0]
+ /P 42 0 R
+ /Pg 3 0 R
+>>
+endobj
+{{object 8 0}} <<
+ /Type /StructElem
+ /S /Document
+ /K [9 0 R]
+ /P 5 0 R
+ /T (TitleText)
+ /Pg 3 0 R
+>>
+endobj
+{{object 9 0}} <<
+ /Type /StructElem
+ /S /Para
+ /K [10 0 R]
+ /P 8 0 R
+ /Pg 3 0 R
+>>
+endobj
+{{object 10 0}} <<
+ /Type /StructElem
+ /S /Para
+ /K [11 0 R]
+ /P 9 0 R
+ /Pg 3 0 R
+>>
+endobj
+{{object 11 0}} <<
+ /Type /StructElem
+ /S /Para
+ /K [12 0 R]
+ /P 10 0 R
+ /Pg 3 0 R
+>>
+endobj
+{{object 12 0}} <<
+ /Type /StructElem
+ /S /Para
+ /K [13 0 R]
+ /P 11 0 R
+ /Pg 3 0 R
+>>
+endobj
+{{object 13 0}} <<
+ /Type /StructElem
+ /S /Para
+ /K [14 0 R]
+ /P 12 0 R
+ /Pg 3 0 R
+>>
+endobj
+{{object 14 0}} <<
+ /Type /StructElem
+ /S /Para
+ /K [15 0 R]
+ /P 13 0 R
+ /Pg 3 0 R
+>>
+endobj
+{{object 15 0}} <<
+ /Type /StructElem
+ /S /Para
+ /K [16 0 R]
+ /P 14 0 R
+ /Pg 3 0 R
+>>
+endobj
+{{object 16 0}} <<
+ /Type /StructElem
+ /S /Para
+ /K [17 0 R]
+ /P 15 0 R
+ /Pg 3 0 R
+>>
+endobj
+{{object 17 0}} <<
+ /Type /StructElem
+ /S /Para
+ /K [18 0 R]
+ /P 16 0 R
+ /Pg 3 0 R
+>>
+endobj
+{{object 18 0}} <<
+ /Type /StructElem
+ /S /Para
+ /K [19 0 R]
+ /P 17 0 R
+ /Pg 3 0 R
+>>
+endobj
+{{object 19 0}} <<
+ /Type /StructElem
+ /S /Para
+ /K [20 0 R]
+ /P 18 0 R
+ /Pg 3 0 R
+>>
+endobj
+{{object 20 0}} <<
+ /Type /StructElem
+ /S /Para
+ /K [21 0 R]
+ /P 19 0 R
+ /Pg 3 0 R
+>>
+endobj
+{{object 21 0}} <<
+ /Type /StructElem
+ /S /Para
+ /K [22 0 R]
+ /P 20 0 R
+ /Pg 3 0 R
+>>
+endobj
+{{object 22 0}} <<
+ /Type /StructElem
+ /S /Para
+ /K [23 0 R]
+ /P 21 0 R
+ /Pg 3 0 R
+>>
+endobj
+{{object 23 0}} <<
+ /Type /StructElem
+ /S /Para
+ /K [24 0 R]
+ /P 22 0 R
+ /Pg 3 0 R
+>>
+endobj
+{{object 24 0}} <<
+ /Type /StructElem
+ /S /Para
+ /K [25 0 R]
+ /P 23 0 R
+ /Pg 3 0 R
+>>
+endobj
+{{object 25 0}} <<
+ /Type /StructElem
+ /S /Para
+ /K [26 0 R]
+ /P 24 0 R
+ /Pg 3 0 R
+>>
+endobj
+{{object 26 0}} <<
+ /Type /StructElem
+ /S /Para
+ /K [27 0 R]
+ /P 25 0 R
+ /Pg 3 0 R
+>>
+endobj
+{{object 27 0}} <<
+ /Type /StructElem
+ /S /Para
+ /K [28 0 R]
+ /P 26 0 R
+ /Pg 3 0 R
+>>
+endobj
+{{object 28 0}} <<
+ /Type /StructElem
+ /S /Para
+ /K [29 0 R]
+ /P 27 0 R
+ /Pg 3 0 R
+>>
+endobj
+{{object 29 0}} <<
+ /Type /StructElem
+ /S /Para
+ /K [30 0 R]
+ /P 28 0 R
+ /Pg 3 0 R
+>>
+endobj
+{{object 30 0}} <<
+ /Type /StructElem
+ /S /Para
+ /K [31 0 R]
+ /P 29 0 R
+ /Pg 3 0 R
+>>
+endobj
+{{object 31 0}} <<
+ /Type /StructElem
+ /S /Para
+ /K [32 0 R]
+ /P 30 0 R
+ /Pg 3 0 R
+>>
+endobj
+{{object 32 0}} <<
+ /Type /StructElem
+ /S /Para
+ /K [33 0 R]
+ /P 31 0 R
+ /Pg 3 0 R
+>>
+endobj
+{{object 33 0}} <<
+ /Type /StructElem
+ /S /Para
+ /K [34 0 R]
+ /P 32 0 R
+ /Pg 3 0 R
+>>
+endobj
+{{object 34 0}} <<
+ /Type /StructElem
+ /S /Para
+ /K [35 0 R]
+ /P 33 0 R
+ /Pg 3 0 R
+>>
+endobj
+{{object 35 0}} <<
+ /Type /StructElem
+ /S /Para
+ /K [36 0 R]
+ /P 34 0 R
+ /Pg 3 0 R
+>>
+endobj
+{{object 36 0}} <<
+ /Type /StructElem
+ /S /Para
+ /K [37 0 R]
+ /P 35 0 R
+ /Pg 3 0 R
+>>
+endobj
+{{object 37 0}} <<
+ /Type /StructElem
+ /S /Para
+ /K [38 0 R]
+ /P 36 0 R
+ /Pg 3 0 R
+>>
+endobj
+{{object 38 0}} <<
+ /Type /StructElem
+ /S /Para
+ /K [39 0 R]
+ /P 37 0 R
+ /Pg 3 0 R
+>>
+endobj
+{{object 39 0}} <<
+ /Type /StructElem
+ /S /Para
+ /K [40 0 R]
+ /P 38 0 R
+ /Pg 3 0 R
+>>
+endobj
+{{object 40 0}} <<
+ /Type /StructElem
+ /S /Para
+ /K [41 0 R]
+ /P 39 0 R
+ /Pg 3 0 R
+>>
+endobj
+{{object 41 0}} <<
+ /Type /StructElem
+ /S /Para
+ /K [42 0 R]
+ /P 40 0 R
+ /Pg 3 0 R
+>>
+endobj
+{{object 42 0}} <<
+ /Type /StructElem
+ /S /Para
+ /K [7 0 R]
+ /P 41 0 R
+ /Pg 3 0 R
+>>
+endobj
+{{xref}}
+{{trailer}}
+{{startxref}}
+%%EOF
diff --git a/testing/resources/tagged_nested.pdf b/testing/resources/tagged_nested.pdf
new file mode 100644
index 0000000..8e09360
--- /dev/null
+++ b/testing/resources/tagged_nested.pdf
@@ -0,0 +1,395 @@
+%PDF-1.7
+% ò¤ô
+1 0 obj <<
+ /Type /Catalog
+ /Pages 2 0 R
+ /StructTreeRoot 5 0 R
+ /Lang (en-US)
+ /MarkInfo <<
+ /Marked true
+ >>
+>>
+endobj
+2 0 obj <<
+ /Type /Pages
+ /Count 1
+ /Kids [3 0 R]
+>>
+endobj
+3 0 obj <<
+ /Type /Page
+ /Parent 2 0 R
+ /Contents 4 0 R
+ /MediaBox [0 0 612 792]
+ /StructParents 0
+>>
+endobj
+4 0 obj <<
+ /Length 65
+>>
+stream
+BT
+/Para<</MCID 0>>
+BMC
+0 0 Td
+/F1 18 Tf
+(Sample Text) Tj
+EMC
+ET
+endstream
+endobj
+5 0 obj <<
+ /Type /StructTreeRoot
+ /ParentTree 6 0 R
+ /K [8 0 R]
+ /RoleMap <<
+ /Document /Document
+ /Para /Para
+ >>
+>>
+endobj
+6 0 obj <<
+ /Nums [0 [7 0 R]]
+>>
+endobj
+7 0 obj <<
+ /Type /StructElem
+ /S /Para
+ /K [0]
+ /P 42 0 R
+ /Pg 3 0 R
+>>
+endobj
+8 0 obj <<
+ /Type /StructElem
+ /S /Document
+ /K [9 0 R]
+ /P 5 0 R
+ /T (TitleText)
+ /Pg 3 0 R
+>>
+endobj
+9 0 obj <<
+ /Type /StructElem
+ /S /Para
+ /K [10 0 R]
+ /P 8 0 R
+ /Pg 3 0 R
+>>
+endobj
+10 0 obj <<
+ /Type /StructElem
+ /S /Para
+ /K [11 0 R]
+ /P 9 0 R
+ /Pg 3 0 R
+>>
+endobj
+11 0 obj <<
+ /Type /StructElem
+ /S /Para
+ /K [12 0 R]
+ /P 10 0 R
+ /Pg 3 0 R
+>>
+endobj
+12 0 obj <<
+ /Type /StructElem
+ /S /Para
+ /K [13 0 R]
+ /P 11 0 R
+ /Pg 3 0 R
+>>
+endobj
+13 0 obj <<
+ /Type /StructElem
+ /S /Para
+ /K [14 0 R]
+ /P 12 0 R
+ /Pg 3 0 R
+>>
+endobj
+14 0 obj <<
+ /Type /StructElem
+ /S /Para
+ /K [15 0 R]
+ /P 13 0 R
+ /Pg 3 0 R
+>>
+endobj
+15 0 obj <<
+ /Type /StructElem
+ /S /Para
+ /K [16 0 R]
+ /P 14 0 R
+ /Pg 3 0 R
+>>
+endobj
+16 0 obj <<
+ /Type /StructElem
+ /S /Para
+ /K [17 0 R]
+ /P 15 0 R
+ /Pg 3 0 R
+>>
+endobj
+17 0 obj <<
+ /Type /StructElem
+ /S /Para
+ /K [18 0 R]
+ /P 16 0 R
+ /Pg 3 0 R
+>>
+endobj
+18 0 obj <<
+ /Type /StructElem
+ /S /Para
+ /K [19 0 R]
+ /P 17 0 R
+ /Pg 3 0 R
+>>
+endobj
+19 0 obj <<
+ /Type /StructElem
+ /S /Para
+ /K [20 0 R]
+ /P 18 0 R
+ /Pg 3 0 R
+>>
+endobj
+20 0 obj <<
+ /Type /StructElem
+ /S /Para
+ /K [21 0 R]
+ /P 19 0 R
+ /Pg 3 0 R
+>>
+endobj
+21 0 obj <<
+ /Type /StructElem
+ /S /Para
+ /K [22 0 R]
+ /P 20 0 R
+ /Pg 3 0 R
+>>
+endobj
+22 0 obj <<
+ /Type /StructElem
+ /S /Para
+ /K [23 0 R]
+ /P 21 0 R
+ /Pg 3 0 R
+>>
+endobj
+23 0 obj <<
+ /Type /StructElem
+ /S /Para
+ /K [24 0 R]
+ /P 22 0 R
+ /Pg 3 0 R
+>>
+endobj
+24 0 obj <<
+ /Type /StructElem
+ /S /Para
+ /K [25 0 R]
+ /P 23 0 R
+ /Pg 3 0 R
+>>
+endobj
+25 0 obj <<
+ /Type /StructElem
+ /S /Para
+ /K [26 0 R]
+ /P 24 0 R
+ /Pg 3 0 R
+>>
+endobj
+26 0 obj <<
+ /Type /StructElem
+ /S /Para
+ /K [27 0 R]
+ /P 25 0 R
+ /Pg 3 0 R
+>>
+endobj
+27 0 obj <<
+ /Type /StructElem
+ /S /Para
+ /K [28 0 R]
+ /P 26 0 R
+ /Pg 3 0 R
+>>
+endobj
+28 0 obj <<
+ /Type /StructElem
+ /S /Para
+ /K [29 0 R]
+ /P 27 0 R
+ /Pg 3 0 R
+>>
+endobj
+29 0 obj <<
+ /Type /StructElem
+ /S /Para
+ /K [30 0 R]
+ /P 28 0 R
+ /Pg 3 0 R
+>>
+endobj
+30 0 obj <<
+ /Type /StructElem
+ /S /Para
+ /K [31 0 R]
+ /P 29 0 R
+ /Pg 3 0 R
+>>
+endobj
+31 0 obj <<
+ /Type /StructElem
+ /S /Para
+ /K [32 0 R]
+ /P 30 0 R
+ /Pg 3 0 R
+>>
+endobj
+32 0 obj <<
+ /Type /StructElem
+ /S /Para
+ /K [33 0 R]
+ /P 31 0 R
+ /Pg 3 0 R
+>>
+endobj
+33 0 obj <<
+ /Type /StructElem
+ /S /Para
+ /K [34 0 R]
+ /P 32 0 R
+ /Pg 3 0 R
+>>
+endobj
+34 0 obj <<
+ /Type /StructElem
+ /S /Para
+ /K [35 0 R]
+ /P 33 0 R
+ /Pg 3 0 R
+>>
+endobj
+35 0 obj <<
+ /Type /StructElem
+ /S /Para
+ /K [36 0 R]
+ /P 34 0 R
+ /Pg 3 0 R
+>>
+endobj
+36 0 obj <<
+ /Type /StructElem
+ /S /Para
+ /K [37 0 R]
+ /P 35 0 R
+ /Pg 3 0 R
+>>
+endobj
+37 0 obj <<
+ /Type /StructElem
+ /S /Para
+ /K [38 0 R]
+ /P 36 0 R
+ /Pg 3 0 R
+>>
+endobj
+38 0 obj <<
+ /Type /StructElem
+ /S /Para
+ /K [39 0 R]
+ /P 37 0 R
+ /Pg 3 0 R
+>>
+endobj
+39 0 obj <<
+ /Type /StructElem
+ /S /Para
+ /K [40 0 R]
+ /P 38 0 R
+ /Pg 3 0 R
+>>
+endobj
+40 0 obj <<
+ /Type /StructElem
+ /S /Para
+ /K [41 0 R]
+ /P 39 0 R
+ /Pg 3 0 R
+>>
+endobj
+41 0 obj <<
+ /Type /StructElem
+ /S /Para
+ /K [42 0 R]
+ /P 40 0 R
+ /Pg 3 0 R
+>>
+endobj
+42 0 obj <<
+ /Type /StructElem
+ /S /Para
+ /K [7 0 R]
+ /P 41 0 R
+ /Pg 3 0 R
+>>
+endobj
+xref
+0 43
+0000000000 65535 f
+0000000015 00000 n
+0000000145 00000 n
+0000000208 00000 n
+0000000322 00000 n
+0000000438 00000 n
+0000000575 00000 n
+0000000616 00000 n
+0000000701 00000 n
+0000000810 00000 n
+0000000899 00000 n
+0000000989 00000 n
+0000001080 00000 n
+0000001171 00000 n
+0000001262 00000 n
+0000001353 00000 n
+0000001444 00000 n
+0000001535 00000 n
+0000001626 00000 n
+0000001717 00000 n
+0000001808 00000 n
+0000001899 00000 n
+0000001990 00000 n
+0000002081 00000 n
+0000002172 00000 n
+0000002263 00000 n
+0000002354 00000 n
+0000002445 00000 n
+0000002536 00000 n
+0000002627 00000 n
+0000002718 00000 n
+0000002809 00000 n
+0000002900 00000 n
+0000002991 00000 n
+0000003082 00000 n
+0000003173 00000 n
+0000003264 00000 n
+0000003355 00000 n
+0000003446 00000 n
+0000003537 00000 n
+0000003628 00000 n
+0000003719 00000 n
+0000003810 00000 n
+trailer <<
+ /Root 1 0 R
+ /Size 43
+>>
+startxref
+3900
+%%EOF
