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Date:      Thu, 18 Apr 2024 13:37:17 GMT
From:      Kristof Provost <kp@FreeBSD.org>
To:        src-committers@FreeBSD.org, dev-commits-src-all@FreeBSD.org, dev-commits-src-branches@FreeBSD.org
Subject:   git: bf0700716a2e - stable/13 - tcpdump: cope with incorrect packet lengths
Message-ID:  <202404181337.43IDbHtW041597@gitrepo.freebsd.org>

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The branch stable/13 has been updated by kp:

URL: https://cgit.FreeBSD.org/src/commit/?id=bf0700716a2e04464311e0b585b947d7d3e825b9

commit bf0700716a2e04464311e0b585b947d7d3e825b9
Author:     Kristof Provost <kp@FreeBSD.org>
AuthorDate: 2024-04-01 09:42:14 +0000
Commit:     Kristof Provost <kp@FreeBSD.org>
CommitDate: 2024-04-18 07:41:28 +0000

    tcpdump: cope with incorrect packet lengths
    
    It's possible for the capture buffer to be smaller than indicated by the
    header length. However, pfsync_print() only took the header length into
    account. As a result we could read outside of the buffer.
    
    Check that we have at least the expected amount of data before we start
    parsing.
    
    PR:             278034
    MFC after:      2 weeks
    Sponsored by:   Rubicon Communications, LLC ("Netgate")
    Differential Revision:  https://reviews.freebsd.org/D44580
    
    (cherry picked from commit 4848eb3af2a91b133c4b70cb9b71dd92ffec7f46)
---
 contrib/tcpdump/print-pfsync.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/contrib/tcpdump/print-pfsync.c b/contrib/tcpdump/print-pfsync.c
index dc1cd039f5b0..cb1c3f3828fa 100644
--- a/contrib/tcpdump/print-pfsync.c
+++ b/contrib/tcpdump/print-pfsync.c
@@ -86,7 +86,7 @@ pfsync_ip_print(netdissect_options *ndo , const u_char *bp, u_int len)
 {
 	struct pfsync_header *hdr = (struct pfsync_header *)bp;
 
-	if (len < PFSYNC_HDRLEN)
+	if (len < PFSYNC_HDRLEN || !ND_TTEST_LEN(bp, len))
 		ND_PRINT((ndo, "[|pfsync]"));
 	else
 		pfsync_print(ndo, hdr, bp + sizeof(struct pfsync_header),



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