print-ospf: guard RI LSA TLV length before subtraction#1441
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TristanInSec wants to merge 1 commit into
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print-ospf: guard RI LSA TLV length before subtraction#1441TristanInSec wants to merge 1 commit into
TristanInSec wants to merge 1 commit into
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… TLVs The RI LSA parser passes tlv_length - 4 to ospf_print_ri_lsa_sid_label_range_tlv() without first checking that tlv_length >= 4. When tlv_length is 0-3, the unsigned subtraction wraps to a large value, causing the called function's while loop to read past the TLV boundary. Add a minimum length check before the subtraction, consistent with other RI LSA TLV handlers that already guard their subtractions (e.g., lines 818 and 847 check tlv_length > 12). Signed-off-by: Tristan <tristan@talencesecurity.com>
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The RI LSA TLV dispatch passes
tlv_length - 4toospf_print_ri_lsa_sid_label_range_tlv()for TLV types 9 (SID/LabelRange) and 14 (SR Local Block) without checking
tlv_length >= 4.When
tlv_lengthis 0–3, the unsigned subtraction wraps to a largevalue, causing the callee's
while (tlv_length != 0)loop to readpast the TLV boundary into adjacent packet data.
The fix adds a
tlv_length < 4guard that prints a bogus-lengthdiagnostic and returns, consistent with other TLV handlers in the
same function (e.g. lines 818/847).
Found by manual audit of commit 9ec6904.