"mkdir a ab; mv a ab ab" causes segfault

[Adam Sampson]

Hiya. I've just upgraded my fileutils to 4.0 (using the stock source from
ftp.gnu.org), and noticed what appears to be a minor bug. I'm using glibc
2.2.2, gcc 2.95.2, and Linux 2.4.2-ac18. A friend has reproduced this on a
Redhat 6.2 system.

While experimenting with config files, I did "mkdir .sawfish_old; mv
.sawfish* .sawfish_old" and got a segfault; with a bit of experimentation I
reduced this to "mkdir a ab; mv a ab ab" to consistently produce a segfault:

(azz:~/src/fileutils-4.0/src) mkdir a ab
(azz:~/src/fileutils-4.0/src) gdb /bin/mv
GNU gdb 4.17
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GDB is free software, covered by the GNU General Public License, and you are
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There is absolutely no warranty for GDB.  Type "show warranty" for details.
This GDB was configured as "i586-pc-linux-gnu"...
(gdb) run a ab ab
Starting program: /bin/mv a ab ab
/bin/mv:
Program received signal SIGSEGV, Segmentation fault.
0x4007f399 in _IO_vfprintf () at _i18n_number.h:49
_i18n_number.h:49: No such file or directory.
(gdb) where
#0  0x4007f399 in _IO_vfprintf () at _i18n_number.h:49
#1  0x40082379 in buffered_vfprintf (s=0x4013d180,
    format=0x804f280 "%s: won't create hard link %s' to directory %s'",
    args=0xbfffeed8) at vfprintf.c:2087
#2  0x4007d9ff in _IO_vfprintf () at _i18n_number.h:49
#3  0x400fcebe in __error (status=0, errnum=0,
    message=0x804f280 "%s: won't create hard link %s' to directory %s'")
    at error.c:153
#4  0x804ac85 in copy_internal (src_path=0x8051de0 "ab/a",
    dst_path=0x8051df0 "ab/ab/a", new_dst=1, device=5698,
    ancestors=0xbffff12c, x=0xbffff428, move_mode=0,
    copy_into_self=0xbffff100, rename_succeeded=0x0) at copy.c:606
#5  0x8049fd3 in copy_dir (src_path_in=0xbffff667 "ab",
    dst_path_in=0x80516a8 "ab/ab", new_dst=1, src_sb=0xbffff294,
    ancestors=0xbffff12c, x=0xbffff428, copy_into_self=0xbffff384)
    at copy.c:139
#6  0x804aeb8 in copy_internal (src_path=0xbffff667 "ab",
    dst_path=0x80516a8 "ab/ab", new_dst=1, device=0, ancestors=0x0,
    x=0xbffff428, move_mode=1, copy_into_self=0xbffff384,
    rename_succeeded=0xbffff388) at copy.c:679
#7  0x804b7d7 in copy (src_path=0xbffff667 "ab", dst_path=0x80516a8 "ab/ab",
    nonexistent_dst=0, options=0xbffff428, copy_into_self=0xbffff384,
    rename_succeeded=0xbffff388) at copy.c:936
---Type <return> to continue, or q <return> to quit---
#8  0x8049631 in do_move (source=0xbffff667 "ab", dest=0x80516a8 "ab/ab",
    x=0xbffff428) at mv.c:180
#9  0x80498d0 in movefile (source=0xbffff667 "ab", dest=0xbffff66a "ab",
    dest_is_dir=1, x=0xbffff428) at mv.c:310
#10 0x8049ddb in main (argc=4, argv=0xbffff4ec) at mv.c:449
#11 0x4004c243 in Letext () at ../sysdeps/generic/libc-start.c:130
(gdb) frame 4
#4  0x804ac85 in copy_internal (src_path=0x8051de0 "ab/a",
    dst_path=0x8051df0 "ab/ab/a", new_dst=1, device=5698,
    ancestors=0xbffff12c, x=0xbffff428, move_mode=0,
    copy_into_self=0xbffff100, rename_succeeded=0x0) at copy.c:606
606               error (0, 0, _("%s: won't create hard link %s' to
directory %s'"),
(gdb) list
601           /* Avoid damaging the destination filesystem by refusing to
preserve
602              hard-linked directories (which are found at least in Netapp
snapshot
603              directories).  */
604           if (S_ISDIR (src_type))
605             {
606               error (0, 0, _("%s: won't create hard link %s' to
directory %s'"),
607                      dst_path, earlier_file);
608               goto un_backup;
609             }
610   
(gdb) print dst_path
$1 = 0x8051df0 "ab/ab/a"
(gdb) print earlier_file
$2 = 0x80516a8 "ab/ab"

Thanks,

-- 

Adam Sampson
address@hidden