#20 trn: SIGSEGV in article selector

[Anonymous]

-- System Information
Debian Release: 3.0
Kernel Version: Linux shrapnel 2.4.18 #4 Sat Mar 23
13:42:15 EST 2002 i686 unknown

Trn version: 4.0-test76 (Apr 2, 2001).
Configured for both NNTP and local news access.

PROBLEM:
Something stomped the ap handed to get_cached_line().
FWIW, the .newsrc in use at the time of the failure is
fairly large and some newsgroups in that file are on
some very long lines describing which articles have
been read. I'm not sure if this is relevant info
but seemed possibly worth mentioning. The newsgroup
that had just been entered at the time of the failure
does not have a particularly long .newsrc line but
was visited soon after visiting some groups with
some very long lines, like this:

alt.bestjobsusa.computer.jobs:
1-71450,71452-71454,71456-71457,71459-71462,71464-71467,71469-71471,71473-71474,71477,71479-71481,71483-71484,71486-71487,71490,7
1492,71495-71496,71499,71501,71503,71507-71508,71511-71512,71515,71519-71522,71525-71527,71530-71534,71536-71540,71542-71543,71545,71547-71552,71554-71559,71561
,71564,71568-71569,71571,71574,71577-71578,71580,71582,71585,71588-71590,71592-71595,71600,71603,71615-71616,71618,71620,71623-71625,71627,71630,71636,71638,716
41-71643,71645-71648,71651-71654,71659-71661,71666,71669-71670,71675,71677-71681,71683-71684,71686,71689,71693-71695,71702,71706-71707,71709-71710,71712,71715-7
1720,71724,71726-71728,71731,71733,71735,71738-71739,71744,71746,71749-71750,71753,71755-71757,71760-71764,71766,71768,71770,71772-71773,71777-71780,71782,71784
-71788,71790-71793,71795-71798,71800,71803-71804,71807,71811-71815,71817,71820,71822-71823,71827,71829-71833,71835,71838-71839,71841,71843,71845,71847-71848,718
50,71852-71853,71855-71856,71858,71860-71862,71864-71866,71869-71870,71872,71875,71879-71880,71882,71884,71887-71888,71890,71892,71894-71896,71898,71901,71903-7
1904,71907,71909,71915-71916,71920,71923-71925,71927,71929-71934,71936-71938,71944-71946,71948,71950-71951,71955,71960-71968,71970-71971,71976-71977,71979,71981
,71984-71985,71989-71991,71993,71995-71996,71999,72007-72009,72011-72012,72015-72016,72021,72023,72025-72029,72031,72034-72035,72038-72039,72041,72043,72046-720
49,72054,72057-72061,72064,72068-72072,72074,72076-72077,72079,72085-72086,72088-72089,72094,72096,72098,72102-72104,72106-72107,72110,72112,72115-72117,72119-7
2120,72124-72125,72127,72130-72131,72134-72136,72145-72146,72148-72149,72151,72156,72160-72163,72165-72166,72168-72169,72174-72175,72177,72179,72182,72184,72187
-72188,72192,72197,72199,72201,72203-72207,72209-72210,72213-72214,72217-72219,72222-72223,72231,72234,72236-72238,72240-72241,72244,72246-72248,72251,72253-722
54,72260,72262,72264-72272,72274,72277,72280,72283,72287-72294,72296,72299-72300,72305-72306,72308,72310,72313-72316,72318,72322,72326-72328,72331,72333-72334,7
2336-72337,72339-72340,72343,72346-72347,72349,72352,72354,72357-72358,72360,72363,72365,72375-72376,72378-72379,72382,72388-72391,72393-72398,72400-72402,72405
-72407,72411-72412,72414,72416,72418-72419,72421-72423,72425-72428,72432-72433,72435-72437,72440,72445,72447,72449,72453-72455,72458,72460-72461,72463-72464,724
68-72470,72473,72475,72478,72480,72482-72483,72485-72486,72489,72491,72494-72499,72501,72504,72506-72509,72512,72514,72516-72517,72519-72520,72522-72523,72526-7
2529,72531,72533,72537-72538,72540,72543,72547,72551-72552,72554-72556,72558-72560,72562-72563,72567-72569,72571-72572,72576,72578-72579,72581-72582,72584,72588
,72590-72591,72594,72599-72600,72604,72606,72608,72611,72613,72615-72616,72619,72621-72624,72626-72628,72630,72633-72634,72637,72639-72640,72643-72644,72646-726
48,72650,72652,72654-72659,72661,72663-72667,72671,72675-72676,72678-72679,72681-72683,72686-72688,72690-72692,72695-72697,72700-72701,72703-72704,72706-72707,7
2711-72712,72714-72716,72718-72721,72723-72724,72726-72727,72731-72733,72736,72738,72741,72743,72745,72749,72751-72753,72757,72759-72760,72763-72764,72766,72769
-72775,72778,72780-72784,72786,72788-72789,72791,72793,72796-72797,72799,72802,72804-72805,72807,72812,72814,72818-72819,72822-72827,72829-72830,72832,72835-728
37,72839,72844,72846,72850-72851,72853,72855,72860,72862,72865,72867-72868,72872-72873,72877-72879,72881,72883-72884,72891,72894-72899,72901-72902,72904-72905,7
2909-72912,72914,72916-72919,72921-72924,72926-72929,72932,72934,72936,72938-72943,72945,72950-72951,72953-72954,72963-72965,72967,72969,72976-72978,72980,72984
,72988,72990-72992,72994,72997,73001,73003-73004,73006,73009,73014,73016,73018,73021,73023-73025,73029-73030,73032-73033,73036-73039,73041,73044,73047-73049,730
53-73054,73057,73059,73061,73064,73066,73069-73070,73075,73077,73081,73086-73087,73090-73091,73093,73098,73102-73103,73107-73108,73110,73113-73114,73117-73119,7
3121-73122,73124,73126,73128-73130,73132,73135-73140,73142,73146,73148-73151,73153-73156,73161,73163-73167,73170-73171,73179,73181,73188-73190,73193-73194,73198
,73200-73201,73203-73204,73208-73211,73214-73215,73218,73220,73224-73227,73230-73231,73233-73236,73239,73241,73243-73244,73247,73250,73253-73254,73262-73264,732
67,73270-73271,73273-73275,73279-73280,73285,73289,73291,73297-73298,74226,74366,74414,74605,74633,74659,75418,76230

alt.bestjobsusa.conn.jobs: 1-845,887,937

alt.bestjobsusa.engineering.jobs:
1-1146,1160,1172,1174,1180,1187-1189,1194,1199,1203,1216-1217

alt.bestjobsusa.jobs.offered:
1-50022,50024,50026,50028-50034,50036-50042,50044,50048,50050,50052,50055,50064-50065,50069,50074,50081-50082,50085-50087,50089,50
091,50093-50094,50097-50098,50100,50102-50107,50111,50117,50129-50131,50133-50135,50137-50138,50154-50155,50157,50162,50164,50166,50171,50173,50176,50182,50184-
50185,50189,50192-50194,50201,50204,50207-50209,50214,50219-50222,50224,50230,50236-50240,50243,50246,50248-50251,50257,50261,50264,50266,50268,50270,50272-5027
3,50275,50278,50282-50283,50285-50286,50288-50290,50294,50300-50305,50308,50311-50313,50315-50317,50322-50326,50331,50333-50334,50336-50337,50339,50341-50342,50
351,50365-50367,50373-50374,50380-50381,50383,50387,50392-50393,50396,50400-50401,50404,50406,50408,50420,50424,50426,50430,50435,50440,50442-50445,50447-50448,
50450,50452,50462-50465,50468,50471-50473,50479,50481,50486-50487,50489,50491-50494,50498-50499,50503,50507-50508,50512-50520,50522-50523,50529,50532,50537,5053
9,50543,50545,50556,50559,50562-50563,50566,50578-50579,50581,50596,50601,50605,50611,50620,50623,50625,50627-50628,50631,50633,50635,50637-50638,50648-50649,50
653-50654,50658-50660,50662-50670,50672,50675-50684,50687-50688,50690-50691,50695-50696,50705-50706,50719,50724,50732,50734,50739-50743,50745,50749-50750,50752,
50759,50763,50765-50766,50770-50771,50779-50783,50785,50787-50788,50792-50793,50799,50804-50807,50809,50811,50817,50819,50822,50824,50826,50830,50833,50835-5083
6,50843-50845,50847,50855-50856,50859,50868,50870,50877,50885-50887,50889,50891-50892,50895,50897-50899,50901,50904-50906,50908,50911-50912,50914,50917-50921,50
927,50931,50934-50935,50937,50939,50951-50953,50962,50971-50972,50977,50987,50992-50993,50999-51000,51004,51006,51008-51009,51019,51026-51028,51030-51031,51034,
51036-51037,51040-51041,51043,51045,51051-51056,51058-51060,51063-51064,51069-51071,51073,51081-51082,51084-51089,51091,51097-51104,51107,51109-51110,51112-5111
5,51123,51127,51131,51133-51134,51138-51139,51143,51146,51148,51152-51153,51156,51159,51161,51163-51166,51168,51171-51175,51184,51187,51189,51191-51194,51197,51
200-51202,51207,51209,51215-51216,51226,51229,51243,51245,51247,51249,51258,51262-51266,51268,51270-51271,51274-51275,51287,51295-51298,51305,51316-51319,51324,
51326,51339,51341,51346,51348,51356,51361,51365-51367,51369,51377,51380,51386,51390-51393,51400,51407,51409,51411,51413,51417-51420,51422-51423,51425,51428,5143
0-51434,51436,51439-51441,51444,51450,51455,51461,51474,51478-51479,51491-51492,51780,52241,52243-52244,52253-52254,52257-52260,52395,52655,52662,52754,52764,52
926,53036,53079,53235,53260,53278,54035

alt.bestjobsusa.kansas.jobs! 1-295

Here's what GDB had to say - I was running trn under
GDB after compiling it -g:

Program received signal SIGSEGV, Segmentation fault.

(gdb) where
#0 0x08050a2b in get_cached_line (ap=0x8487120,
which_line=28, no_truncs=1) at cache.c:403
#1 0x080509b4 in fetchcache (artnum=6325,
which_line=28, fill_cache=0) at cache.c:379
#2 0x080568c4 in prefetchlines (artnum=6325,
which_line=28, copy=0) at head.c:478
#3 0x0805140c in cache_subjects () at cache.c:813
#4 0x08051312 in cache_until_key () at cache.c:765
#5 0x08075b09 in sel_input () at rt-select.c:904
#6 0x08074804 in article_selector (cmd=43) at
rt-select.c:184
#7 0x080603be in art_switch () at ng.c:1309
#8 0x0805f326 in do_newsgroup (start_command=0x809cfec
"") at ng.c:514
#9 0x08081f5b in input_newsgroup () at trn.c:764
#10 0x08081392 in do_multirc () at trn.c:328
#11 0x08080e83 in main (argc=5, argv=0xbffff634) at
trn.c:152
#12 0x400c66cf in __libc_start_main () from
/lib/libc.so.6

(gdb) print ap
$1 = (ARTICLE *) 0x8487120

(gdb) print ap->subj
$2 = (SUBJECT *) 0x20474e49

(gdb) x/s ap
0x8487120: "OR PLANNING & FINANCIAL REPORTING
ANALYST 79043"

(gdb) print ap
$3 = (ARTICLE *) 0x8487120

(gdb) print *ap
$4 = {num = 1344295503, date = 1313751372, subj =
0x20474e49, from = 0x49462026 <Address 0x49462026 out
of bounds>,
msgid = 0x434e414e <Address 0x434e414e out of
bounds>, xrefs = 0x204c4149 <Address 0x204c4149 out of
bounds>, parent = 0x4f504552, child1 = 0x4e495452,
sibling = 0x4e412047, subj_next = 0x53594c41, bytes =
959914068, lines = 3355696, flags = 368, flags2 = 0,
autofl = 40}

(gdb) list
398 {
399 register char* s;
400
401 switch (which_line) {
402 case SUBJ_LINE:
403 if (!ap->subj || (no_truncs &&
(ap->subj->flags & SF_SUBJTRUNCED)))
404 s = NULL;
405 else
406 s = ap->subj->str + ((ap->flags &
AF_HAS_RE) ? 0 : 4);
407 break;

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