https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=266442
--- Comment #9 from commit-h...@freebsd.org --- A commit in branch stable/13 references this bug: URL: https://cgit.FreeBSD.org/src/commit/?id=1da7a8a066150bf132b3e1a48fad009212a0010a commit 1da7a8a066150bf132b3e1a48fad009212a0010a Author: Cy Schubert <c...@freebsd.org> AuthorDate: 2023-02-02 00:49:08 +0000 Commit: Cy Schubert <c...@freebsd.org> CommitDate: 2023-02-09 21:19:41 +0000 ipfilter: Fix use after free on packet with broken lengths Under the scenario with a packet with length of 67 bytes, a header length using the default of 20 bytes and a TCP data offset (th_off) of 48 will cause m_pullup() to fail to make sure bytes are arragned contiguously. m_pullup() will free the mbuf chain and return a null. ipfilter stores the resultant mbuf address (or the resulting NULL) in its fr_info_t structure. Unfortuntely the eroneous packet is not flagged for drop. This results in a kernel page fault at line 410 of sys/netinet/ip_fastfwd.c as it tries to use a now previously freed, by m_pullup(), mbuf. PR: 266442 Reported by: Robert Morris <r...@lcs.mit.edu> (cherry picked from commit 79f7745c098a766d34a4e072cdd1a06e6d0829d5) sys/netpfil/ipfilter/netinet/fil.c | 13 ++++++++++++- 1 file changed, 12 insertions(+), 1 deletion(-) -- You are receiving this mail because: You are on the CC list for the bug.
