Hello,
in version 0.00.04, which you commited to git three hours ago, the bug
is still present, although much more seldom.
I enabled core dumping, and looked at it through gdb.
Please find attached at "bt full" for version 0.00.04-1 as gdb prints it
for the version with debug symbols. It appears that the error is
("still"?) with accessing mmaps.
For comparison: core dumps with version 0.00.03 mostly have their stack
corrupted, and the rest crashes somewhere deep in 'scanf' while trying
to read things from the stack; so probably stack corruption, too.
Btw, can you enable debug symbols again? One litte "-g" in the CFLAGS
increases the binary size only slightly, and makes debugging easier. I
did that by hand when reproducing the bug.
Cheers,
Ben Wiederhake
PS: Today I learned how *not* to use reportbug. I assumed --body-file
would either accept it as the full message, or allow me to edit it once
more. Oh well.
user@machine:~/workspace/pagein$ gdb ./pagein core
GNU gdb (Debian 7.12-6) 7.12.0.20161007-git
Copyright (C) 2016 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>
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and "show warranty" for details.
This GDB was configured as "i686-linux-gnu".
Type "show configuration" for configuration details.
For bug reporting instructions, please see:
<http://www.gnu.org/software/gdb/bugs/>.
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For help, type "help".
Type "apropos word" to search for commands related to "word"...
Reading symbols from ./pagein...done.
[New LWP 28377]
Core was generated by `./pagein -p 1073'.
Program terminated with signal SIGSEGV, Segmentation fault.
#0 pagein_proc_mmap (pages_touched=<synthetic pointer>, prot=0xbfeeaa73
"r--p",
path=0xbfeeaae0 "/usr/lib/i386-linux-gnu/libgstreamer-1.0.so.0.1004.0",
len=<optimized out>,
end=3077554176, begin=<optimized out>, page_size=4096, mappings=0x811c28e8)
at pagein.c:263
263 x += *ptr;
(gdb) set pagination off
(gdb) bt full
#0 pagein_proc_mmap (pages_touched=<synthetic pointer>, prot=0xbfeeaa73
"r--p", path=0xbfeeaae0 "/usr/lib/i386-linux-gnu/libgstreamer-1.0.so.0.1004.0",
len=<optimized out>, end=3077554176, begin=<optimized out>, page_size=4096,
mappings=0x811c28e8) at pagein.c:263
ptr = 0xb76fb000 <error: Cannot access memory at address 0xb76fb000>
x = <optimized out>
fd = 5
statbuf = {st_dev = 65025, __pad1 = 0, st_ino = 7606200, st_mode =
33188, st_nlink = 1, st_uid = 0, st_gid = 0, st_rdev = 0, __pad2 = 0, st_size =
1377772, st_blksize = 4096, st_blocks = 2696, st_atim = {tv_sec = 1497960752,
tv_nsec = 83782983}, st_mtim = {tv_sec = 1487856812, tv_nsec = 0}, st_ctim =
{tv_sec = 1490879804, tv_nsec = 871008154}, __glibc_reserved4 = 0,
__glibc_reserved5 = 0}
off = 3077550080
prot_flags = <optimized out>
mapped = 0xb770d000
#1 pagein_proc (mappings=0x811c28e8, page_size=4096, pid=1073,
procs=0xbfeecf38, kthreads=0xbfeecf3c, total_pages_touched=0xbfeecf60) at
pagein.c:337
begin = 3077541888
end = 3077554176
len = <optimized out>
off = <optimized out>
off_end = <optimized out>
byte = 0 '\000'
mapped = 0x0
path =
"/usr/lib/i386-linux-gnu/libgstreamer-1.0.so.0.1004.0\000\000-le32d4.cache-4\000png.so",
'\000' <repeats 947 times>
prot = "r--p"
path = "/proc/1073/maps", '\000' <repeats 1073 times>...
buffer = "b76f9000-b76fc000 r--p 0014c000 fe:01 7606200
/usr/lib/i386-linux-gnu/libgstreamer-1.0.so.0.1004.0\n\000\000\000e32d4.cache-4\n\000ng.so\n\000)\n",
'\000' <repeats 2236 times>...
fdmem = 3
rc = 0
fpmap = 0x811c2008
pages = 26343
pages_touched = 22240
has_maps = <optimized out>
#2 0x80054e0e in main (argc=<optimized out>, argv=<optimized out>) at
pagein.c:493
ret = <optimized out>
memfree_begin = 152728
memfree_end = -5227627996823549632
swapfree_begin = 1039448
swapfree_end = 0
delta = <optimized out>
total_pages_touched = 0
procs = 0
total_procs = <optimized out>
kthreads = 0
scale = <optimized out>
usage = {ru_utime = {tv_sec = -1074868352, tv_usec = -2147137980},
ru_stime = {tv_sec = 0, tv_usec = -1074868204}, {ru_maxrss = -1217433600,
__ru_maxrss_word = -1217433600}, {ru_ixrss = 10, __ru_ixrss_word = 10},
{ru_idrss = -1, __ru_idrss_word = -1}, {ru_isrss = -1217433600, __ru_isrss_word
= -1217433600}, {ru_minflt = -1219166696, __ru_minflt_word = -1219166696},
{ru_majflt = -1217324968, __ru_majflt_word = -1217324968}, {ru_nswap =
-1217433600, __ru_nswap_word = -1217433600}, {ru_inblock = -1074868108,
__ru_inblock_word = -1074868108}, {ru_oublock = -1217155840, __ru_oublock_word
= -1217155840}, {ru_msgsnd = 524288, __ru_msgsnd_word = 524288}, {ru_msgrcv =
-1, __ru_msgrcv_word = -1}, {ru_nsignals = -2147123200, __ru_nsignals_word =
-2147123200}, {ru_nvcsw = 3, __ru_nvcsw_word = 3}, {ru_nivcsw = -2147131877,
__ru_nivcsw_word = -2147131877}}
pid = <optimized out>
mappings = <optimized out>
(gdb)
