After replace libc.so.6 in i386-linux-gnu,gdb show segmentation fault

I'm trying to do a pwn challenge , and for simulate environment need replace libc.so.6 with given lib. After doing this gdb can't work and show the following information.I want know Where is the problem? How to fix it.

gdb-peda$ start

Program received signal SIGSEGV, Segmentation fault.
[----------------------------------registers-----------------------------------]
EAX: 0xf7f42722 ("__vdso_clock_gettime")
EBX: 0x343661 ('a64')
ECX: 0xffffd1ec --> 0xffffd1f0 --> 0x0 
EDX: 0x343661 ('a64')
ESI: 0xf7ffc8a0 --> 0x0 
EDI: 0xffffd2dc --> 0xffffd49a ("CLUTTER_IM_MODULE=xim")
EBP: 0xe0 
ESP: 0xffffd1bc --> 0xf7f0648a (mov    edx,DWORD PTR [esp+0x18])
EIP: 0x0
EFLAGS: 0x10296 (carry PARITY ADJUST zero SIGN trap INTERRUPT direction overflow)
[-------------------------------------code-------------------------------------]
Invalid $PC address: 0x0
[------------------------------------stack-------------------------------------]
0000| 0xffffd1bc --> 0xf7f0648a (mov    edx,DWORD PTR [esp+0x18])
0004| 0xffffd1c0 --> 0x343831 ('184')
0008| 0xffffd1c4 --> 0xffffd210 --> 0xf7f42718 ("LINUX_2.6")
0012| 0xffffd1c8 --> 0x0 
0016| 0xffffd1cc --> 0x0 
0020| 0xffffd1d0 --> 0x0 
0024| 0xffffd1d4 --> 0x0 
0028| 0xffffd1d8 --> 0x0 
[------------------------------------------------------------------------------]
Legend: code, data, rodata, value
Stopped reason: SIGSEGV
0x00000000 in ?? ()
gdb-peda$ bt
#0  0x00000000 in ?? ()
#1  0xf7f0648a in ?? () from /lib/i386-linux-gnu/libc.so.6
#2  0xf7e0249c in ?? () from /lib/i386-linux-gnu/libc.so.6
#3  0xf7fe4309 in ?? () from /lib/ld-linux.so.2
#4  0xf7fe4442 in ?? () from /lib/ld-linux.so.2
#5  0xf7fd50fa in ?? () from /lib/ld-linux.so.2

gdb-peda$ vmmap
Start      End        Perm  Name
0x56555000 0x56556000 r-xp  /root/ELFs/dubblesorts
0x56556000 0x56557000 r--p  /root/ELFs/dubblesorts
0x56557000 0x56558000 rw-p  /root/ELFs/dubblesorts
0xf7dea000 0xf7f97000 r-xp  /lib/i386-linux-gnu/libc.so.6
0xf7f97000 0xf7f98000 ---p  /lib/i386-linux-gnu/libc.so.6
0xf7f98000 0xf7f9a000 r--p  /lib/i386-linux-gnu/libc.so.6
0xf7f9a000 0xf7f9b000 rw-p  /lib/i386-linux-gnu/libc.so.6
0xf7f9b000 0xf7f9e000 rw-p  mapped
0xf7fcd000 0xf7fcf000 rw-p  mapped
0xf7fcf000 0xf7fd2000 r--p  [vvar]
0xf7fd2000 0xf7fd4000 r-xp  [vdso]
0xf7fd4000 0xf7fd5000 r--p  /lib/i386-linux-gnu/ld-2.28.so
0xf7fd5000 0xf7ff1000 r-xp  /lib/i386-linux-gnu/ld-2.28.so
0xf7ff1000 0xf7ffb000 r--p  /lib/i386-linux-gnu/ld-2.28.so
0xf7ffc000 0xf7ffd000 r--p  /lib/i386-linux-gnu/ld-2.28.so
0xf7ffd000 0xf7ffe000 rw-p  /lib/i386-linux-gnu/ld-2.28.so
0xfffdd000 0xffffe000 rw-p  [stack]