问题[dynamic-linking](unix)

自 2018 年以来，我一直在运行相同的 32 位第三方闭源二进制文件。本周在 Debiantrixie/testing服务器上（可能是由于libc6过渡？），该程序在启动时开始崩溃。不幸的是，我无法让原始供应商为我重新编译它。

我唯一的提示是在标准输出上打印的这些行：

Start of process LocalCtrl...
SL - error in dlopen(libDSS_Operator.so):
LocalCtrl initialization failed...

我要么让它工作起来，要么就承诺永远支持 Deb12。

排除故障/修复此问题的最佳方法是什么？

我可以使用此示例程序在更加简单的环境中重现此过程：

#include <stdio.h>
#include <dlfcn.h>

int main() {
    void* so = dlopen(
        "/opt/<package>/Cots/OPERATOR/libDSS_Operator.so", 
        RTLD_NOW
    );

    if (so == NULL) {
        printf("dlopen() failed: %s\n", dlerror());
        return 1;
    } 
    printf("Success\n");
    dlclose(so);
    return 0;
}

我看了一下ldd、、、和strace。LD_DEBUG=libsreadelf

在 Deb11 机器上，该过程运行正常，我得到：

$ dpkg --print-foreign-architectures
i386

$ sudo apt install gcc-multilib

$ gcc main.c -m32 -ldl

$ file a.out
a.out: ELF 32-bit LSB pie executable, Intel 80386, version 1 (SYSV), dynamically linked, interpreter /lib/ld-linux.so.2, BuildID[sha1]=eabedb331eafcdef4e2f839f71df7fc7330069d2, for GNU/Linux 3.2.0, not stripped

$ ./a.out
Success

$ ldd /opt/<package>/Cots/OPERATOR/libDSS_Operator.so
    linux-gate.so.1 (0xf7f25000)
    libc.so.6 => /lib/i386-linux-gnu/libc.so.6 (0xf7d1b000)
    libm.so.6 => /lib/i386-linux-gnu/libm.so.6 (0xf7c17000)
    /lib/ld-linux.so.2 (0xf7f27000)

$ file /opt/<pacakge>/Cots/OPERATOR/libDSS_Operator.so
/opt/<package>/Cots/OPERATOR/libDSS_Operator.so: ELF 32-bit LSB shared object, Intel 80386, version 1 (SYSV), dynamically linked, not stripped

$ strace ./a.out
execve("./a.out", ["./a.out"], 0x7ffeb7d8e5b0 /* 22 vars */) = 0
[ Process PID=13616 runs in 32 bit mode. ]
brk(NULL)                               = 0x5851f000
access("/etc/ld.so.nohwcap", F_OK)      = -1 ENOENT (No such file or directory)
mmap2(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0xf7f78000
access("/etc/ld.so.preload", R_OK)      = -1 ENOENT (No such file or directory)
openat(AT_FDCWD, "/etc/ld.so.cache", O_RDONLY|O_LARGEFILE|O_CLOEXEC) = 3
fstat64(3, {st_mode=S_IFREG|0644, st_size=102958, ...}) = 0
mmap2(NULL, 102958, PROT_READ, MAP_PRIVATE, 3, 0) = 0xf7f5e000
close(3)                                = 0
access("/etc/ld.so.nohwcap", F_OK)      = -1 ENOENT (No such file or directory)
openat(AT_FDCWD, "/lib/i386-linux-gnu/libdl.so.2", O_RDONLY|O_LARGEFILE|O_CLOEXEC) = 3
read(3, "\177ELF\1\1\1\0\0\0\0\0\0\0\0\0\3\0\3\0\1\0\0\0000\21\0\0004\0\0\0"..., 512) = 512
fstat64(3, {st_mode=S_IFREG|0644, st_size=17924, ...}) = 0
mmap2(NULL, 20596, PROT_READ, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0xf7f58000
mmap2(0xf7f59000, 8192, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x1000) = 0xf7f59000
mmap2(0xf7f5b000, 4096, PROT_READ, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x3000) = 0xf7f5b000
mmap2(0xf7f5c000, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x3000) = 0xf7f5c000
close(3)                                = 0
access("/etc/ld.so.nohwcap", F_OK)      = -1 ENOENT (No such file or directory)
openat(AT_FDCWD, "/lib/i386-linux-gnu/libc.so.6", O_RDONLY|O_LARGEFILE|O_CLOEXEC) = 3
read(3, "\177ELF\1\1\1\3\0\0\0\0\0\0\0\0\3\0\3\0\1\0\0\0\200\260\1\0004\0\0\0"..., 512) = 512
fstat64(3, {st_mode=S_IFREG|0755, st_size=1987668, ...}) = 0
mmap2(NULL, 1996648, PROT_READ, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0xf7d70000
mprotect(0xf7d89000, 1871872, PROT_NONE) = 0
mmap2(0xf7d89000, 1392640, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x19000) = 0xf7d89000
mmap2(0xf7edd000, 475136, PROT_READ, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x16d000) = 0xf7edd000
mmap2(0xf7f52000, 12288, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x1e1000) = 0xf7f52000
mmap2(0xf7f55000, 10088, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0) = 0xf7f55000
close(3)                                = 0
set_thread_area({entry_number=-1, base_addr=0xf7f794c0, limit=0x0fffff, seg_32bit=1, contents=0, read_exec_only=0, limit_in_pages=1, seg_not_present=0, useable=1}) = 0 (entry_number=12)
mprotect(0xf7f52000, 8192, PROT_READ)   = 0
mprotect(0xf7f5c000, 4096, PROT_READ)   = 0
mprotect(0x56648000, 4096, PROT_READ)   = 0
mprotect(0xf7faa000, 4096, PROT_READ)   = 0
munmap(0xf7f5e000, 102958)              = 0
brk(NULL)                               = 0x5851f000
brk(0x58540000)                         = 0x58540000
brk(0x58541000)                         = 0x58541000
openat(AT_FDCWD, "/opt/<package>/Cots/OPERATOR/libDSS_Operator.so", O_RDONLY|O_LARGEFILE|O_CLOEXEC) = 3
read(3, "\177ELF\1\1\1\0\0\0\0\0\0\0\0\0\3\0\3\0\1\0\0\0X\6\0\0004\0\0\0"..., 512) = 512
fstat64(3, {st_mode=S_IFREG|0644, st_size=4398, ...}) = 0
mmap2(NULL, 6844, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0xf7f76000
mmap2(0xf7f77000, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0) = 0xf7f77000
mprotect(0xf7faa000, 2636, PROT_READ|PROT_WRITE) = 0
mprotect(0xf7faa000, 2636, PROT_READ)   = 0
mprotect(0xffa54000, 4096, PROT_READ|PROT_WRITE|PROT_EXEC|PROT_GROWSDOWN) = 0
close(3)                                = 0
openat(AT_FDCWD, "/etc/ld.so.cache", O_RDONLY|O_LARGEFILE|O_CLOEXEC) = 3
fstat64(3, {st_mode=S_IFREG|0644, st_size=102958, ...}) = 0
mmap2(NULL, 102958, PROT_READ, MAP_PRIVATE, 3, 0) = 0xf7d56000
close(3)                                = 0
access("/etc/ld.so.nohwcap", F_OK)      = -1 ENOENT (No such file or directory)
openat(AT_FDCWD, "/lib/i386-linux-gnu/libm.so.6", O_RDONLY|O_LARGEFILE|O_CLOEXEC) = 3
read(3, "\177ELF\1\1\1\3\0\0\0\0\0\0\0\0\3\0\3\0\1\0\0\0\220\241\0\0004\0\0\0"..., 512) = 512
fstat64(3, {st_mode=S_IFREG|0644, st_size=1058344, ...}) = 0
mmap2(NULL, 1060976, PROT_READ, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0xf7c52000
mmap2(0xf7c5c000, 790528, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0xa000) = 0xf7c5c000
mmap2(0xf7d1d000, 225280, PROT_READ, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0xcb000) = 0xf7d1d000
mmap2(0xf7d54000, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x101000) = 0xf7d54000
close(3)                                = 0
mprotect(0xf7d54000, 4096, PROT_READ)   = 0
mprotect(0xf7f76000, 4096, PROT_READ|PROT_WRITE|PROT_EXEC) = 0
mprotect(0xf7f76000, 4096, PROT_READ|PROT_EXEC) = 0
munmap(0xf7d56000, 102958)              = 0
fstat64(1, {st_mode=S_IFCHR|0620, st_rdev=makedev(0x88, 0x4), ...}) = 0
write(1, "Success\n", 8Success
)                = 8
munmap(0xf7f76000, 6844)                = 0
munmap(0xf7c52000, 1060976)             = 0
exit_group(0)                           = ?
+++ exited with 0 +++


$ LD_DEBUG=libs ./a.out
     13617: find library=libdl.so.2 [0]; searching
     13617:  search cache=/etc/ld.so.cache
     13617:   trying file=/lib/i386-linux-gnu/libdl.so.2
     13617: 
     13617: find library=libc.so.6 [0]; searching
     13617:  search cache=/etc/ld.so.cache
     13617:   trying file=/lib/i386-linux-gnu/libc.so.6
     13617: 
     13617: 
     13617: calling init: /lib/i386-linux-gnu/libc.so.6
     13617: 
     13617: 
     13617: calling init: /lib/i386-linux-gnu/libdl.so.2
     13617: 
     13617: 
     13617: initialize program: ./a.out
     13617: 
     13617: 
     13617: transferring control: ./a.out
     13617: 
     13617: find library=libm.so.6 [0]; searching
     13617:  search cache=/etc/ld.so.cache
     13617:   trying file=/lib/i386-linux-gnu/libm.so.6
     13617: 
     13617: 
     13617: calling init: /lib/i386-linux-gnu/libm.so.6
     13617: 
Success
     13617: 
     13617: calling fini: /opt/<package>/Cots/OPERATOR/libDSS_Operator.so [0]
     13617: 
     13617: 
     13617: calling fini: /lib/i386-linux-gnu/libm.so.6 [0]
     13617: 
     13617: 
     13617: calling fini: ./a.out [0]
     13617: 
     13617: 
     13617: calling fini: /lib/i386-linux-gnu/libdl.so.2 [0]
     13617: 

在遇到问题的 Deb13 服务器上，输出要短得多：

$ dpkg --print-foreign-architectures
i386

$ sudo apt install gcc-multilib

$ gcc main.c -m32 -ldl

$ file a.out
a.out: ELF 32-bit LSB pie executable, Intel 80386, version 1 (SYSV), dynamically linked, interpreter /lib/ld-linux.so.2, BuildID[sha1]=ab5677099dd8d392861f817ee098264a76a16792, for GNU/Linux 3.2.0, not stripped

$ ./a.out 
dlopen() failed: /opt/<package>/Cots/OPERATOR/libDSS_Operator.so: cannot enable executable stack as shared object requires: Invalid argument

$ ldd /opt/<package>/Cots/OPERATOR/libDSS_Operator.so 
    linux-gate.so.1 (0xf7ed4000)
    libc.so.6 => /lib/i386-linux-gnu/libc.so.6 (0xf7c70000)
    libm.so.6 => /lib/i386-linux-gnu/libm.so.6 (0xf7b53000)
    /lib/ld-linux.so.2 (0xf7ed6000)

$ file /opt/<pacakge>/Cots/OPERATOR/libDSS_Operator.so
.../libDSS_Operator.so: ELF 32-bit LSB shared object, Intel 80386, version 1 (SYSV), dynamically linked, not stripped

$ strace ./a.out
execve("./a.out", ["./a.out"], 0x7ffccb5bca20 /* 24 vars */) = 0
[ Process PID=8276 runs in 32 bit mode. ]
brk(NULL)                               = 0x57fac000
mmap2(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0xf7f4a000
access("/etc/ld.so.preload", R_OK)      = -1 ENOENT (No such file or directory)
openat(AT_FDCWD, "/etc/ld.so.cache", O_RDONLY|O_LARGEFILE|O_CLOEXEC) = 3
statx(3, "", AT_STATX_SYNC_AS_STAT|AT_NO_AUTOMOUNT|AT_EMPTY_PATH, STATX_BASIC_STATS, {stx_mask=STATX_BASIC_STATS|STATX_MNT_ID, stx_attributes=0, stx_mode=S_IFREG|0644, stx_size=122402, ...}) = 0
mmap2(NULL, 122402, PROT_READ, MAP_PRIVATE, 3, 0) = 0xf7f2c000
close(3)                                = 0
openat(AT_FDCWD, "/lib/i386-linux-gnu/libc.so.6", O_RDONLY|O_LARGEFILE|O_CLOEXEC) = 3
read(3, "\177ELF\1\1\1\3\0\0\0\0\0\0\0\0\3\0\3\0\1\0\0\0\0O\2\0004\0\0\0"..., 512) = 512
statx(3, "", AT_STATX_SYNC_AS_STAT|AT_NO_AUTOMOUNT|AT_EMPTY_PATH, STATX_BASIC_STATS, {stx_mask=STATX_BASIC_STATS|STATX_MNT_ID, stx_attributes=0, stx_mode=S_IFREG|0755, stx_size=2315004, ...}) = 0
mmap2(NULL, 2349360, PROT_READ, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0xf7cee000
mmap2(0xf7d11000, 1609728, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x23000) = 0xf7d11000
mmap2(0xf7e9a000, 544768, PROT_READ, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x1ac000) = 0xf7e9a000
mmap2(0xf7f1f000, 12288, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x231000) = 0xf7f1f000
mmap2(0xf7f22000, 39216, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0) = 0xf7f22000
close(3)                                = 0
set_thread_area({entry_number=-1, base_addr=0xf7f4b500, limit=0x0fffff, seg_32bit=1, contents=0, read_exec_only=0, limit_in_pages=1, seg_not_present=0, useable=1}) = 0 (entry_number=12)
set_tid_address(0xf7f4b568)             = 8276
set_robust_list(0xf7f4b56c, 12)         = 0
rseq(0xf7f4b480, 0x20, 0, 0x53053053)   = 0
mprotect(0xf7f1f000, 8192, PROT_READ)   = 0
mprotect(0x56575000, 4096, PROT_READ)   = 0
mprotect(0xf7f86000, 8192, PROT_READ)   = 0
ugetrlimit(RLIMIT_STACK, {rlim_cur=8192*1024, rlim_max=RLIM_INFINITY}) = 0
munmap(0xf7f2c000, 122402)              = 0
getrandom("\x81\x4a\xa4\xb7", 4, GRND_NONBLOCK) = 4
brk(NULL)                               = 0x57fac000
brk(0x57fcd000)                         = 0x57fcd000
brk(0x57fce000)                         = 0x57fce000
openat(AT_FDCWD, "/opt/<package>/Cots/OPERATOR/libDSS_Operator.so", O_RDONLY|O_LARGEFILE|O_CLOEXEC) = 3
read(3, "\177ELF\1\1\1\0\0\0\0\0\0\0\0\0\3\0\3\0\1\0\0\0X\6\0\0004\0\0\0"..., 512) = 512
statx(3, "", AT_STATX_SYNC_AS_STAT|AT_NO_AUTOMOUNT|AT_EMPTY_PATH, STATX_BASIC_STATS, {stx_mask=STATX_BASIC_STATS|STATX_MNT_ID, stx_attributes=0, stx_mode=S_IFREG|0644, stx_size=4398, ...}) = 0
mmap2(NULL, 6844, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0xf7f48000
mmap2(0xf7f49000, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0) = 0xf7f49000
close(3)                                = 0
munmap(0xf7f48000, 6844)                = 0
statx(1, "", AT_STATX_SYNC_AS_STAT|AT_NO_AUTOMOUNT|AT_EMPTY_PATH, STATX_BASIC_STATS, {stx_mask=STATX_BASIC_STATS|STATX_MNT_ID, stx_attributes=0, stx_mode=S_IFCHR|0620, stx_size=0, ...}) = 0
write(1, "dlopen() failed: /opt/..."..., 153dlopen() failed: /opt/<package>/Cots/OPERATOR/libDSS_Operator.so: cannot enable executable stack as shared object requires: Invalid argument
) = 153
exit_group(1)                           = ?
+++ exited with 1 +++

$ LD_DEBUG=libs ./a.out
      8277: find library=libc.so.6 [0]; searching
      8277:  search cache=/etc/ld.so.cache
      8277:   trying file=/lib/i386-linux-gnu/libc.so.6
      8277: 
      8277: 
      8277: calling init: /lib/ld-linux.so.2
      8277: 
      8277: 
      8277: calling init: /lib/i386-linux-gnu/libc.so.6
      8277: 
      8277: 
      8277: initialize program: ./a.out
      8277: 
      8277: 
      8277: transferring control: ./a.out
      8277: 
dlopen() failed: /opt/<package>/Cots/OPERATOR/libDSS_Operator.so: cannot enable executable stack as shared object requires: Invalid argument
      8277: 
      8277: calling fini:  [0]
      8277: 
      8277: 
      8277: calling fini: /lib/i386-linux-gnu/libc.so.6 [0]
      8277: 
      8277: 
      8277: calling fini: /lib/ld-linux.so.2 [0]
      8277:

两台机器上的库的patchelf --print-needed、objdump -p、几乎完全相同，而且出奇地简洁。我做了一个，deb11 和 deb13 输出之间的唯一区别是的符号表的 LOCAL 条目仅在 deb13 中有一个填充的“名称”列。这可能不是很有趣。这是 deb13 输出：readelf -adiffreadelf

$ patchelf --print-needed /opt/<package>/Cots/OPERATOR/libDSS_Operator.so
libc.so.6
libm.so.6

$ objdump -p /opt/<package>/Cots/OPERATOR/libDSS_Operator.so

/opt/<package>/Cots/OPERATOR/libDSS_Operator.so:     file format elf32-i386

Program Header:
    LOAD off    0x00000000 vaddr 0x00000000 paddr 0x00000000 align 2**12
         filesz 0x000009e0 memsz 0x000009e0 flags r-x
    LOAD off    0x000009e0 vaddr 0x000019e0 paddr 0x000019e0 align 2**12
         filesz 0x000000dc memsz 0x000000dc flags rw-
 DYNAMIC off    0x00000a2c vaddr 0x00001a2c paddr 0x00001a2c align 2**2
         filesz 0x00000090 memsz 0x00000090 flags rw-

Dynamic Section:
  NEEDED               libc.so.6
  NEEDED               libm.so.6
  HASH                 0x00000094
  STRTAB               0x0000034c
  SYMTAB               0x0000015c
  STRSZ                0x00000121
  SYMENT               0x00000010
  REL                  0x00000470
  RELSZ                0x000001e8
  RELENT               0x00000008
  TEXTREL              0x00000000
  RELCOUNT             0x0000003c




$ readelf -a /opt/<package>/Cots/OPERATOR/libDSS_Operator.so 
ELF Header:
  Magic:   7f 45 4c 46 01 01 01 00 00 00 00 00 00 00 00 00 
  Class:                             ELF32
  Data:                              2's complement, little endian
  Version:                           1 (current)
  OS/ABI:                            UNIX - System V
  ABI Version:                       0
  Type:                              DYN (Shared object file)
  Machine:                           Intel 80386
  Version:                           0x1
  Entry point address:               0x658
  Start of program headers:          52 (bytes into file)
  Start of section headers:          2940 (bytes into file)
  Flags:                             0x0
  Size of this header:               52 (bytes)
  Size of program headers:           32 (bytes)
  Number of program headers:         3
  Size of section headers:           40 (bytes)
  Number of section headers:         17
  Section header string table index: 14

Section Headers:
  [Nr] Name              Type            Addr     Off    Size   ES Flg Lk Inf Al
  [ 0]                   NULL            00000000 000000 000000 00      0   0  0
  [ 1] .hash             HASH            00000094 000094 0000c8 04   A  2   0  4
  [ 2] .dynsym           DYNSYM          0000015c 00015c 0001f0 10   A  3  14  4
  [ 3] .dynstr           STRTAB          0000034c 00034c 000121 00   A  0   0  1
  [ 4] .rel.dyn          REL             00000470 000470 0001e8 08   A  2   0  4
  [ 5] .text             PROGBITS        00000658 000658 000244 00  AX  0   0  4
  [ 6] .rodata           PROGBITS        000008a0 0008a0 000140 00   A  0   0 16
  [ 7] .data             PROGBITS        000019e0 0009e0 000040 00  WA  0   0 32
  [ 8] .got              PROGBITS        00001a20 000a20 00000c 04  WA  0   0  4
  [ 9] .dynamic          DYNAMIC         00001a2c 000a2c 000090 08  WA  3   0  4
  [10] .sbss             PROGBITS        00001abc 000abc 000000 00   W  0   0  1
  [11] .bss              NOBITS          00001abc 000abc 000000 00  WA  0   0  4
  [12] .comment          PROGBITS        00000000 000abc 000036 00      0   0  1
  [13] .note             NOTE            00000000 000af2 000014 00      0   0  1
  [14] .shstrtab         STRTAB          00000000 000b06 000076 00      0   0  1
  [15] .symtab           SYMTAB          00000000 000e24 000240 10     16  19  4
  [16] .strtab           STRTAB          00000000 001064 0000ca 00      0   0  1
Key to Flags:
  W (write), A (alloc), X (execute), M (merge), S (strings), I (info),
  L (link order), O (extra OS processing required), G (group), T (TLS),
  C (compressed), x (unknown), o (OS specific), E (exclude),
  D (mbind), p (processor specific)

There are no section groups in this file.

Program Headers:
  Type           Offset   VirtAddr   PhysAddr   FileSiz MemSiz  Flg Align
  LOAD           0x000000 0x00000000 0x00000000 0x009e0 0x009e0 R E 0x1000
  LOAD           0x0009e0 0x000019e0 0x000019e0 0x000dc 0x000dc RW  0x1000
  DYNAMIC        0x000a2c 0x00001a2c 0x00001a2c 0x00090 0x00090 RW  0x4

 Section to Segment mapping:
  Segment Sections...
   00     .hash .dynsym .dynstr .rel.dyn .text .rodata 
   01     .data .got .dynamic 
   02     .dynamic 

Dynamic section at offset 0xa2c contains 13 entries:
  Tag        Type                         Name/Value
 0x00000001 (NEEDED)                     Shared library: [libc.so.6]
 0x00000001 (NEEDED)                     Shared library: [libm.so.6]
 0x00000004 (HASH)                       0x94
 0x00000005 (STRTAB)                     0x34c
 0x00000006 (SYMTAB)                     0x15c
 0x0000000a (STRSZ)                      289 (bytes)
 0x0000000b (SYMENT)                     16 (bytes)
 0x00000011 (REL)                        0x470
 0x00000012 (RELSZ)                      488 (bytes)
 0x00000013 (RELENT)                     8 (bytes)
 0x00000016 (TEXTREL)                    0x0
 0x6ffffffa (RELCOUNT)                   60
 0x00000000 (NULL)                       0x0

Relocation section '.rel.dyn' at offset 0x470 contains 61 entries:
 Offset     Info    Type            Sym.Value  Sym. Name
0000068f  00000008 R_386_RELATIVE   
0000069f  00000008 R_386_RELATIVE   
000006cb  00000008 R_386_RELATIVE   
000006db  00000008 R_386_RELATIVE   
000006f6  00000008 R_386_RELATIVE   
00000736  00000008 R_386_RELATIVE   
00000772  00000008 R_386_RELATIVE   
000007a7  00000008 R_386_RELATIVE   
000007b7  00000008 R_386_RELATIVE   
000007e3  00000008 R_386_RELATIVE   
000007f3  00000008 R_386_RELATIVE   
0000080e  00000008 R_386_RELATIVE   
0000084e  00000008 R_386_RELATIVE   
0000088a  00000008 R_386_RELATIVE   
000008a0  00000008 R_386_RELATIVE   
000008a4  00000008 R_386_RELATIVE   
000008a8  00000008 R_386_RELATIVE   
000008ac  00000008 R_386_RELATIVE   
000008b0  00000008 R_386_RELATIVE   
000008b4  00000008 R_386_RELATIVE   
000008c0  00000008 R_386_RELATIVE   
000008c4  00000008 R_386_RELATIVE   
000008c8  00000008 R_386_RELATIVE   
000008cc  00000008 R_386_RELATIVE   
000008d0  00000008 R_386_RELATIVE   
000008d4  00000008 R_386_RELATIVE   
000008e0  00000008 R_386_RELATIVE   
000008e4  00000008 R_386_RELATIVE   
000008e8  00000008 R_386_RELATIVE   
000008ec  00000008 R_386_RELATIVE   
000008f0  00000008 R_386_RELATIVE   
000008f4  00000008 R_386_RELATIVE   
00000900  00000008 R_386_RELATIVE   
00000904  00000008 R_386_RELATIVE   
00000908  00000008 R_386_RELATIVE   
0000090c  00000008 R_386_RELATIVE   
00000910  00000008 R_386_RELATIVE   
00000914  00000008 R_386_RELATIVE   
00000920  00000008 R_386_RELATIVE   
00000924  00000008 R_386_RELATIVE   
00000928  00000008 R_386_RELATIVE   
0000092c  00000008 R_386_RELATIVE   
00000930  00000008 R_386_RELATIVE   
00000934  00000008 R_386_RELATIVE   
00000940  00000008 R_386_RELATIVE   
00000944  00000008 R_386_RELATIVE   
00000948  00000008 R_386_RELATIVE   
0000094c  00000008 R_386_RELATIVE   
00000950  00000008 R_386_RELATIVE   
00000954  00000008 R_386_RELATIVE   
000019e0  00000008 R_386_RELATIVE   
000019e4  00000008 R_386_RELATIVE   
000019e8  00000008 R_386_RELATIVE   
000019ec  00000008 R_386_RELATIVE   
000019f0  00000008 R_386_RELATIVE   
000019f4  00000008 R_386_RELATIVE   
000019f8  00000008 R_386_RELATIVE   
000019fc  00000008 R_386_RELATIVE   
00001a00  00000008 R_386_RELATIVE   
00001a04  00000008 R_386_RELATIVE   
00000665  00000f01 R_386_32          000019e0   listOperators
No processor specific unwind information to decode

Symbol table '.dynsym' contains 31 entries:
   Num:    Value  Size Type    Bind   Vis      Ndx Name
     0: 00000000     0 NOTYPE  LOCAL  DEFAULT  UND 
     1: 00000094     0 SECTION LOCAL  DEFAULT    1 .hash
     2: 0000015c     0 SECTION LOCAL  DEFAULT    2 .dynsym
     3: 0000034c     0 SECTION LOCAL  DEFAULT    3 .dynstr
     4: 00000470     0 SECTION LOCAL  DEFAULT    4 .rel.dyn
     5: 00000658     0 SECTION LOCAL  DEFAULT    5 .text
     6: 000008a0     0 SECTION LOCAL  DEFAULT    6 .rodata
     7: 000019e0     0 SECTION LOCAL  DEFAULT    7 .data
     8: 00001a20     0 SECTION LOCAL  DEFAULT    8 .got
     9: 00001a2c     0 SECTION LOCAL  DEFAULT    9 .dynamic
    10: 00001abc     0 SECTION LOCAL  DEFAULT   10 .sbss
    11: 00001abc     0 SECTION LOCAL  DEFAULT   11 .bss
    12: 00000000     0 SECTION LOCAL  DEFAULT   12 .comment
    13: 00000000     0 SECTION LOCAL  DEFAULT   13 .note
    14: 000007fc    61 FUNC    GLOBAL DEFAULT    5 op_inv_rev
    15: 000019e0    40 OBJECT  GLOBAL DEFAULT    7 listOperators
    16: 00001a2c     0 OBJECT  GLOBAL DEFAULT  ABS _DYNAMIC
    17: 000007c0    59 FUNC    GLOBAL DEFAULT    5 op10_rev
    18: 00000658    19 FUNC    GLOBAL DEFAULT    5 getListOperator
    19: 0000083c    57 FUNC    GLOBAL DEFAULT    5 op_inv2_rev
    20: 000006e4    61 FUNC    GLOBAL DEFAULT    5 op_inv
    21: 00000784    59 FUNC    GLOBAL DEFAULT    5 op3_rev
    22: 00001abc     0 OBJECT  GLOBAL DEFAULT  ABS __bss_start
    23: 00000724    57 FUNC    GLOBAL DEFAULT    5 op_inv2
    24: 00000760    35 FUNC    GLOBAL DEFAULT    5 op_refresh
    25: 000006a8    59 FUNC    GLOBAL DEFAULT    5 op10
    26: 0000066c    59 FUNC    GLOBAL DEFAULT    5 op3
    27: 00000878    35 FUNC    GLOBAL DEFAULT    5 op_refresh_rev
    28: 00001abc     0 OBJECT  GLOBAL DEFAULT  ABS _edata
    29: 00001a20     0 OBJECT  GLOBAL DEFAULT  ABS _GLOBAL_OFFSET_TABLE_
    30: 00001abc     0 OBJECT  GLOBAL DEFAULT  ABS _end

Symbol table '.symtab' contains 36 entries:
   Num:    Value  Size Type    Bind   Vis      Ndx Name
     0: 00000000     0 NOTYPE  LOCAL  DEFAULT  UND 
     1: 00000094     0 SECTION LOCAL  DEFAULT    1 .hash
     2: 0000015c     0 SECTION LOCAL  DEFAULT    2 .dynsym
     3: 0000034c     0 SECTION LOCAL  DEFAULT    3 .dynstr
     4: 00000470     0 SECTION LOCAL  DEFAULT    4 .rel.dyn
     5: 00000658     0 SECTION LOCAL  DEFAULT    5 .text
     6: 000008a0     0 SECTION LOCAL  DEFAULT    6 .rodata
     7: 000019e0     0 SECTION LOCAL  DEFAULT    7 .data
     8: 00001a20     0 SECTION LOCAL  DEFAULT    8 .got
     9: 00001a2c     0 SECTION LOCAL  DEFAULT    9 .dynamic
    10: 00001abc     0 SECTION LOCAL  DEFAULT   10 .sbss
    11: 00001abc     0 SECTION LOCAL  DEFAULT   11 .bss
    12: 00000000     0 SECTION LOCAL  DEFAULT   12 .comment
    13: 00000000     0 SECTION LOCAL  DEFAULT   13 .note
    14: 00000000     0 SECTION LOCAL  DEFAULT   14 .shstrtab
    15: 00000000     0 SECTION LOCAL  DEFAULT   15 .symtab
    16: 00000000     0 SECTION LOCAL  DEFAULT   16 .strtab
    17: 00000000     0 FILE    LOCAL  DEFAULT  ABS operator.c
    18: 00000658     0 NOTYPE  LOCAL  DEFAULT    5 gcc2_compiled.
    19: 000007fc    61 FUNC    GLOBAL DEFAULT    5 op_inv_rev
    20: 000019e0    40 OBJECT  GLOBAL DEFAULT    7 listOperators
    21: 00001a2c     0 OBJECT  GLOBAL DEFAULT  ABS _DYNAMIC
    22: 000007c0    59 FUNC    GLOBAL DEFAULT    5 op10_rev
    23: 00000658    19 FUNC    GLOBAL DEFAULT    5 getListOperator
    24: 0000083c    57 FUNC    GLOBAL DEFAULT    5 op_inv2_rev
    25: 000006e4    61 FUNC    GLOBAL DEFAULT    5 op_inv
    26: 00000784    59 FUNC    GLOBAL DEFAULT    5 op3_rev
    27: 00001abc     0 OBJECT  GLOBAL DEFAULT  ABS __bss_start
    28: 00000724    57 FUNC    GLOBAL DEFAULT    5 op_inv2
    29: 00000760    35 FUNC    GLOBAL DEFAULT    5 op_refresh
    30: 000006a8    59 FUNC    GLOBAL DEFAULT    5 op10
    31: 0000066c    59 FUNC    GLOBAL DEFAULT    5 op3
    32: 00000878    35 FUNC    GLOBAL DEFAULT    5 op_refresh_rev
    33: 00001abc     0 OBJECT  GLOBAL DEFAULT  ABS _edata
    34: 00001a20     0 OBJECT  GLOBAL DEFAULT  ABS _GLOBAL_OFFSET_TABLE_
    35: 00001abc     0 OBJECT  GLOBAL DEFAULT  ABS _end

Histogram for bucket list length (total of 17 buckets):
 Length  Number     % of total  Coverage
      0  7          ( 41.2%)
      1  4          ( 23.5%)     23.5%
      2  5          ( 29.4%)     82.4%
      3  1          (  5.9%)    100.0%

No version information found in this file.

Displaying notes found in: .note
  Owner                Data size    Description
  01.01                0x00000000   NT_VERSION (version)

我减少了一些冗长的内容以patchelf --remove-rpath消除不必要的搜索，但两台机器上都没有变化。

因此，我正在处理的项目使用非系统目录来保存代码使用的一些 DLL。我不想将它们放在系统目录中，因此可执行文件设置了一个 rpath 来查找 DLL。但是，随着越来越多的库被添加，现在有依赖于该目录中其他 DLL 的 DLL。

这些库找不到它们所依赖的 DLL，因为它们不在链接器正在寻找的目录中，例如系统目录。

有没有办法让 DLL 搜索这个特定的非系统目录？比如rpath？图书馆是如何做到的？用于该项目的构建系统是 CMake，如果这有助于答案。

这个答案不起作用，因为库中没有 rPath 标签：https ://unix.stackexchange.com/a/272286/4193

我考虑过使用LD_LIBRARY_PATH, 并且可行，但是打字很烦人，而且让其他人使用该应用程序并不是那么好。如果有办法将rPath标签添加到库中，那将是最好的选择。

指向以前相关问题和答案的指针表示赞赏。

我试图通过将可执行文件直接从一台 Nixos 主机复制到另一台主机来使其正常工作。它仅在其中一台主机上工作/执行。

在旧主机上（它工作的地方）：

[root@XenonKiloCranberry:~/blog]# ldd app
    linux-vdso.so.1 (0x00007fffd68fb000)
    libm.so.6 => /nix/store/7gx4kiv5m0i7d7qkixq2cwzbr10lvxwc-glibc-2.27/lib/libm.so.6 (0x00007f591bf32000)
    libpq.so.5 => /nix/store/sf3jq8d81gx6fmxsi0mhagpgsgpnxf6m-postgresql-9.6.12-lib/lib/libpq.so.5 (0x00007f591bd03000)

在新主机上找不到共享库：

[root@XenonKiloCranberry:~/blog]# ldd /root/blog/app
    linux-vdso.so.1 (0x00007fff6cb89000)
    libm.so.6 => /nix/store/681354n3k44r8z90m35hm8945vsp95h1-glibc-2.27/lib/libm.so.6 (0x00007f927e00f000)
    libpq.so.5 => not found

我确实libpq.so在新主机的 postgresql-lib 目录中看到了一个文件：

[root@XenonKiloCranberry:~/blog]# ll /nix/store/1m0kd7v8yvf5vdmd2jm16w4aal234114-postgresql-9.6.13-lib/lib/libpq.so
lrwxrwxrwx 1 root root 12 Jan  1  1970 /nix/store/1m0kd7v8yvf5vdmd2jm16w4aal234114-postgresql-9.6.13-lib/lib/libpq.so -> libpq.so.5.9

[root@XenonKiloCranberry:~/blog]# ll /nix/var/nix/profiles/system/sw/lib/libpq.so.5
lrwxrwxrwx 1 root root 80 Jan  1  1970 /nix/var/nix/profiles/system/sw/lib/libpq.so.5 -> /nix/store/1m0kd7v8yvf5vdmd2jm16w4aal234114-postgresql-9.6.13-lib/lib/libpq.so.5

我已经[glibc gmp5 postgresql postgresql.lib zlib.dev zlib.out]在我的environment.systemPackages.

我碰巧需要从导出的共享库符号的平面列表中找出哪个库导出了哪些符号。列表中有足够的符号（20 个左右），我不会手动交叉引用每个符号。

我发现这nm -A -D -f sysv <library-name>似乎产生了有用的输出——我可以搜索包含FUNC在第二列中也列出了地址的行。所以我对 中的所有内容都运行了这个命令/usr/lib，并将其重定向到一个文件。

令我惊讶的是，我为解析文件而编写的脚本中的健全性检查报告说存在重复的符号！经调查发现库似乎在导出重复符号？！？

我使用一些 shell 脚本验证了这一点，并且我能够将我使用的命令变成这个^{_{（技术上）}}单行：

readlink -f /lib/* /usr/lib/* \
  | grep -F .so. | sort | uniq \
  | while read x; do nm -A -D -f sysv $x; done \
  | grep FUNC | cut -d'|' -f1 | sort -g | uniq -c | sort -g \
  | sed -n '/^ \+1/!{s/^ \+[0-9]\+ \+//p}' | sed 's/ //g' \
  | tr '\n' '\v' \
  | sed ':1;s/\([^ ]\+\):\([^\v$]\+\)\v\1:/\1:\2|/g;t1' \
  | tr '\v' '\n' \
  | while IFS=: read -a x; do \
     nm -A -D -f sysv "${x[0]}" | grep ":\\(${x[1]//|/\\|}\\).*FUNC"; \
  done

上面的命令将使您的磁盘搜索一小段时间。如果需要，您可以将其分解为重定向到临时文件的块。输出也会很宽（~150 cols）。

我最初在我正在使用的 Debian Squeeze chroot 上运行原始脚本，但出于好奇，我在我的主机系统上运行了上述脚本，以查明 chroot 是否不正常。

嗯...... chroot 报告了超过 90 个重复项，但我的主机（Arch）系统显然有大约 267 个。

该命令通过 greppingnm的输出工作，因此结果有点嘈杂，但看起来像这样：

/usr/lib/libasound.so.2.0.0:snd_pcm_hw_params_get_access|00043700|   T  |              FUNC|00000037|     |.text
/usr/lib/libasound.so.2.0.0:snd_pcm_hw_params_get_access|000436c0|   T  |              FUNC|0000003c|     |.text
/usr/lib/libasound.so.2.0.0:snd_pcm_hw_params_get_access_mask|000458f0|   T  |              FUNC|00000058|     |.text
/usr/lib/libasound.so.2.0.0:snd_pcm_hw_params_get_buffer_size|000432a0|   T  |              FUNC|00000037|     |.text
/usr/lib/libasound.so.2.0.0:snd_pcm_hw_params_get_buffer_size|00043260|   T  |              FUNC|0000003c|     |.text
/usr/lib/libasound.so.2.0.0:snd_pcm_hw_params_get_buffer_size_max|00044ff0|   T  |              FUNC|0000003c|     |.text
/usr/lib/libasound.so.2.0.0:snd_pcm_hw_params_get_buffer_size_max|00045030|   T  |              FUNC|00000037|     |.text
/usr/lib/libasound.so.2.0.0:snd_pcm_hw_params_get_buffer_size_min|000453c0|   T  |              FUNC|00000037|     |.text
/usr/lib/libasound.so.2.0.0:snd_pcm_hw_params_get_buffer_size_min|00045380|   T  |              FUNC|0000003c|     |.text

注意每个符号有两个。地址是不同的，是的，但是......我认为动态链接是通过符号名称工作的，就是这样。（如果您在上面的列表中向右滚动）这些符号都是类型FUNC并且来自该.text部分，这使我更加困惑。

我发布这篇文章是为了了解这里的引擎盖下正在发生什么有趣的魔法。（因为我的系统正在工作......）

如果有人有任何好主意，我可以转储大约 600 行文本 - Pastebin 似乎不再流行，而且我不使用 GitHub - 我很乐意分享完整的输出。

我有一个名为“alpha”的二进制可执行文件，它需要一个链接库（libz.so.1.2.7），它位于/home/username/myproduct/lib/libz.so.1.2.7

在通过执行以下命令生成我的二进制可执行文件之前，我将其导出到我的终端实例。

export LD_LIBRARY_PATH=/home/username/myproduct/lib/:$LD_LIBRARY_PATH

现在，当我生成另一个需要相同库但版本不同的应用程序“bravo”时，即 (libz.so.1.2.8) 可用 /lib/x86_64-linux-gnu/libz.so.1.2.8，系统会抛出以下错误。

version `ZLIB_1.2.3.3' not found (required by /usr/lib/x86_64-linux-gnu/libxml2.so.2)

如果我取消设置LD_LIBRARY_PATH，“bravo”启动正常。我了解上述行为是因为LD_LIBRARY_PATH在查找链接库时优先于定义的目录路径/etc/ld.so.conf，因此发生了上述错误。我只是好奇为什么UNIX / LINUX的开发人员没有设计操作系统来根据层次结构搜索其他目录中的链接库，如果库的第一个实例是不同的版本。

简单地说，UNIX/LINUX 系统遍历一组目录，直到找到所需的库。但是，为什么它在找到预期版本之前不做同样的事情，而不是接受库的第一个实例而不管其版本如何？

其他问题的许多答案有助于解决“无法从共享对象映射段”形式的错误，但它们通常有非常具体的答案，我发现很难将其应用于其他问题。另一方面，我一般找不到有关此错误的任何信息。

谁能给出这个错误的基本描述和（理想情况下）一些常见原因？

很高兴知道，例如，哪个实体引发了错误（内核、进程、程序？）以及常见原因（例如，几乎每个库都被标记​​为可读，那么为什么我不能从中映射呢？） .

我目前正在运行 Ubuntu，尽管我怀疑这适用于许多发行版。

我有与之前发布的这个问题相同的问题，其中/etc/ld.so.preload不拦截正确的架构。一点背景知识：我编译了一个共享对象（64 位），它ld.so.preload在任何二进制执行的文件中都被引用。问题是我ERROR: ld.so: object '/usr/local/lib/mysharedobject.so' from /etc/ld.so.preload cannot be preloaded (wrong ELF class: ELFCLASS64): ignored.在执行 32 位程序时遇到了问题。

要根据该问题的答案解决问题，我必须创建两个目录（例如 in ）lib/i386-linux-gnu并指定in ，以便根据程序架构预加载正确的库。 x86_64-linux-gnu/var/opt/var/opt/$LIB/mysharedobject.so/etc/ld.so.preload

因此，在这种情况下，在基于 Debian 的系统中，/var/opt/$LIB/mysharedobject.so将扩展为：

• /var/opt/lib/i386-linux-gnu/mysharedobject.so对于 32 位程序；
• /var/opt/x86_64-linux-gnu/mysharedobject.so对于 64 位程序。

但是，应用此功能后，我运行的任何二进制文件（例如ls）都将输出以下“错误”：
ERROR: ld.so: object '/var/opt/$LIB/mysharedobject.so' from /etc/ld.so.preload cannot be preloaded (cannot open shared object file): ignored.

如您所见，$LIB 没有扩展到任何东西。我还设置并运行$LD_LIBRARY_PATH以使用此库更新系统，但没有成功。这里有什么问题？/var/optldconfig

假设我在ldd /bin/ls删除 pthread 库的情况下执行。我得到

linux-vdso.so.1 (0x00007ffcc3563000)

libselinux.so.1 => /lib64/libselinux.so.1 (0x00007f87e5459000)
libcap.so.2 => /lib64/libcap.so.2 (0x00007f87e5254000)
libc.so.6 => /lib64/libc.so.6 (0x00007f87e4e92000)
libpcre.so.1 => /lib64/libpcre.so.1 (0x00007f87e4c22000)
libdl.so.2 => /lib64/libdl.so.2 (0x00007f87e4a1e000)
/lib64/ld-linux-x86-64.so.2 (0x00005574bf12e000)
libattr.so.1 => /lib64/libattr.so.1 (0x00007f87e4817000)
libpthread.so.0 => not found

返回码为零。在这种情况下是否有返回错误的命令？类似的东西

#!/bin/bash
if [[ ! -z $(ldd ${target} | grep 'not found') ]]; then
   exit 1
fi

我有一个可执行文件，但是当我运行它时，我得到“没有这样的文件或目录”

$ chmod a+x bin 
$ file bin 
bin: ELF 64-bit LSB executable, x86-64, version 1 (SYSV), dynamically linked, interpreter /lib/ld64.so.1, not stripped
$ ./bin 
bash: ./bin: No such file or directory

请注意，这个可执行文件实际上是 ELF 64 位，操作系统也是如此。

据我了解，so文件是动态库。我们可以使用ldd它来打印它的依赖关系。

例如，我可以执行ldd -r /usr/lib/aarch64-linux-gnu/libstdc++.so.6得到如下输出：

    linux-vdso.so.1 =>  (0x0000ffff793f7000)
    libm.so.6 => /lib/aarch64-linux-gnu/libm.so.6 (0x0000ffff79173000)
    libc.so.6 => /lib/aarch64-linux-gnu/libc.so.6 (0x0000ffff7902c000)
    /lib/ld-linux-aarch64.so.1 (0x0000aaaae0a5d000)
    libgcc_s.so.1 => /lib/aarch64-linux-gnu/libgcc_s.so.1 (0x0000ffff7900b000)

但是，今天当我执行时ldd -r /lib/ld-linux-aarch64.so.1，我得到了这个：

statically linked

为什么我会得到这样的输出？这是什么意思？