Created attachment 14048 [details]
Reproducers.

Build Information:
Wireshark git master.
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The following crash due to a use-after-free condition can be observed in an ASAN build of Wireshark (current git master), by feeding a malformed file to tshark ("$ ./tshark -nVxr /path/to/file"):

Attached are three files which trigger the crash.

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==5117==ERROR: AddressSanitizer: heap-use-after-free on address 0x61b00001e3b2 at pc 0x000000499bad bp 0x7ffd2111f650 sp 0x7ffd2111ee00
READ of size 4 at 0x61b00001e3b2 thread T0
    #0 0x499bac in memcmp llvm/projects/compiler-rt/lib/asan/../sanitizer_common/sanitizer_common_interceptors.inc:416
    #1 0x37949bc in addresses_equal wireshark/epan/dissectors/./../address.h:140:26
    #2 0x379389a in rsvp_equal wireshark/epan/dissectors/packet-rsvp.c:1886:13
    #3 0x7f77e4ae95ef in g_hash_table_lookup (/lib/x86_64-linux-gnu/libglib-2.0.so.0+0x385ef)
    #4 0x3796e2d in dissect_rsvp_common wireshark/epan/dissectors/packet-rsvp.c:7531:37
    #5 0x37930d4 in dissect_rsvp wireshark/epan/dissectors/packet-rsvp.c:7553:5
    #6 0xaf3794 in call_dissector_through_handle wireshark/epan/packet.c:616:8
    #7 0xae5692 in call_dissector_work wireshark/epan/packet.c:691:9
    #8 0xae4e1d in dissector_try_uint_new wireshark/epan/packet.c:1148:9
    #9 0x29c5318 in ip_try_dissect wireshark/epan/dissectors/packet-ip.c:2001:7
    #10 0x29d0521 in dissect_ip_v4 wireshark/epan/dissectors/packet-ip.c:2485:10
    #11 0xaf3794 in call_dissector_through_handle wireshark/epan/packet.c:616:8
    #12 0xae5692 in call_dissector_work wireshark/epan/packet.c:691:9
    #13 0xae4e1d in dissector_try_uint_new wireshark/epan/packet.c:1148:9
    #14 0xae5a38 in dissector_try_uint wireshark/epan/packet.c:1174:9
    #15 0x24e0824 in dissect_ethertype wireshark/epan/dissectors/packet-ethertype.c:307:21
    #16 0xaf3794 in call_dissector_through_handle wireshark/epan/packet.c:616:8
    #17 0xae5692 in call_dissector_work wireshark/epan/packet.c:691:9
    #18 0xaefb1b in call_dissector_only wireshark/epan/packet.c:2662:8
    #19 0xae09f3 in call_dissector_with_data wireshark/epan/packet.c:2675:8
    #20 0x24dc752 in dissect_eth_common wireshark/epan/dissectors/packet-eth.c:545:5
    #21 0x24d499a in dissect_eth_maybefcs wireshark/epan/dissectors/packet-eth.c:828:5
    #22 0xaf3794 in call_dissector_through_handle wireshark/epan/packet.c:616:8
    #23 0xae5692 in call_dissector_work wireshark/epan/packet.c:691:9
    #24 0xae4e1d in dissector_try_uint_new wireshark/epan/packet.c:1148:9
    #25 0x25dca12 in dissect_frame wireshark/epan/dissectors/packet-frame.c:500:11
    #26 0xaf3794 in call_dissector_through_handle wireshark/epan/packet.c:616:8
    #27 0xae5692 in call_dissector_work wireshark/epan/packet.c:691:9
    #28 0xaefb1b in call_dissector_only wireshark/epan/packet.c:2662:8
    #29 0xae09f3 in call_dissector_with_data wireshark/epan/packet.c:2675:8
    #30 0xadffde in dissect_record wireshark/epan/packet.c:501:3
    #31 0xab6d0d in epan_dissect_run_with_taps wireshark/epan/epan.c:373:2
    #32 0x53c91b in process_packet wireshark/tshark.c:3728:5
    #33 0x535d90 in load_cap_file wireshark/tshark.c:3484:11
    #34 0x52c1df in main wireshark/tshark.c:2197:13

0x61b00001e3b2 is located 50 bytes inside of 1500-byte region [0x61b00001e380,0x61b00001e95c)
freed by thread T0 here:
    #0 0x4d7380 in realloc llvm/projects/compiler-rt/lib/asan/asan_malloc_linux.cc:61
    #1 0x7f77e4aff6ae in g_realloc (/lib/x86_64-linux-gnu/libglib-2.0.so.0+0x4e6ae)
    #2 0x9d71b7 in wtap_read_packet_bytes wireshark/wiretap/wtap.c:1419:2
    #3 0x89ee21 in libpcap_read_packet wireshark/wiretap/libpcap.c:722:7
    #4 0x8991f4 in libpcap_read wireshark/wiretap/libpcap.c:619:9
    #5 0x9d64c2 in wtap_read wireshark/wiretap/wtap.c:1314:7
    #6 0x535c1a in load_cap_file wireshark/tshark.c:3479:12
    #7 0x52c1df in main wireshark/tshark.c:2197:13

previously allocated by thread T0 here:
    #0 0x4d6ff8 in __interceptor_malloc llvm/projects/compiler-rt/lib/asan/asan_malloc_linux.cc:40
    #1 0x7f77e4aff610 in g_malloc (/lib/x86_64-linux-gnu/libglib-2.0.so.0+0x4e610)
    #2 0x83fff6 in wtap_open_offline wireshark/wiretap/file_access.c:1105:2
    #3 0x53214d in cf_open wireshark/tshark.c:4195:9
    #4 0x52bc7e in main wireshark/tshark.c:2188:9

SUMMARY: AddressSanitizer: heap-use-after-free llvm/projects/compiler-rt/lib/asan/../sanitizer_common/sanitizer_common_interceptors.inc:416 in memcmp
Shadow bytes around the buggy address:
  0x0c367fffbc20: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
  0x0c367fffbc30: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
  0x0c367fffbc40: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
  0x0c367fffbc50: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
  0x0c367fffbc60: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
=>0x0c367fffbc70: fd fd fd fd fd fd[fd]fd fd fd fd fd fd fd fd fd
  0x0c367fffbc80: fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd
  0x0c367fffbc90: fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd
  0x0c367fffbca0: fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd
  0x0c367fffbcb0: fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd
  0x0c367fffbcc0: fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd
Shadow byte legend (one shadow byte represents 8 application bytes):
  Addressable:           00
  Partially addressable: 01 02 03 04 05 06 07 
  Heap left redzone:       fa
  Heap right redzone:      fb
  Freed heap region:       fd
  Stack left redzone:      f1
  Stack mid redzone:       f2
  Stack right redzone:     f3
  Stack partial redzone:   f4
  Stack after return:      f5
  Stack use after scope:   f8
  Global redzone:          f9
  Global init order:       f6
  Poisoned by user:        f7
  Container overflow:      fc
  Array cookie:            ac
  Intra object redzone:    bb
  ASan internal:           fe
  Left alloca redzone:     ca
  Right alloca redzone:    cb
==5117==ABORTING
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This bug is subject to a 90 day disclosure deadline. If 90 days elapse without a broadly available patch, then the bug report will automatically become visible to the public.