mirror of git://sourceware.org/git/glibc.git
elf: Refactor process_envvars
It splits between process_envvars_secure and process_envvars_default, with the former used to process arguments for __libc_enable_secure. It does not have any semantic change, just simplify the code so there is no need to handle __libc_enable_secure on each len switch. Checked on x86_64-linux-gnu and aarch64-linux-gnu. Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
This commit is contained in:
Adhemerval Zanella
parent
61d848b554
commit
4369019520
132
elf/rtld.c
132
elf/rtld.c
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@ -2533,7 +2533,67 @@ a filename can be specified using the LD_DEBUG_OUTPUT environment variable.\n");
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}
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static void
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process_envvars (struct dl_main_state *state)
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process_envvars_secure (struct dl_main_state *state)
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{
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char **runp = _environ;
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char *envline;
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while ((envline = _dl_next_ld_env_entry (&runp)) != NULL)
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{
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size_t len = 0;
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while (envline[len] != '\0' && envline[len] != '=')
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++len;
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if (envline[len] != '=')
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/* This is a "LD_" variable at the end of the string without
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a '=' character. Ignore it since otherwise we will access
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invalid memory below. */
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continue;
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switch (len)
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{
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case 5:
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/* For __libc_enable_secure mode, audit pathnames containing slashes
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are ignored. Also, shared audit objects are only loaded only from
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the standard search directories and only if they have set-user-ID
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mode bit enabled. */
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if (memcmp (envline, "AUDIT", 5) == 0)
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audit_list_add_string (&state->audit_list, &envline[6]);
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break;
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case 7:
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/* For __libc_enable_secure mode, preload pathnames containing slashes
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are ignored. Also, shared objects are only preloaded from the
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standard search directories and only if they have set-user-ID mode
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bit enabled. */
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if (memcmp (envline, "PRELOAD", 7) == 0)
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state->preloadlist = &envline[8];
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break;
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}
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}
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/* Extra security for SUID binaries. Remove all dangerous environment
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variables. */
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const char *nextp = UNSECURE_ENVVARS;
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do
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{
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unsetenv (nextp);
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nextp = strchr (nextp, '\0') + 1;
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}
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while (*nextp != '\0');
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if (GLRO(dl_debug_mask) != 0
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|| GLRO(dl_verbose) != 0
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|| GLRO(dl_lazy) != 1
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|| GLRO(dl_bind_not) != 0
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|| state->mode != rtld_mode_normal
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|| state->version_info)
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_exit (5);
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}
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static void
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process_envvars_default (struct dl_main_state *state)
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{
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char **runp = _environ;
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char *envline;
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@ -2556,15 +2616,13 @@ process_envvars (struct dl_main_state *state)
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{
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case 4:
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/* Warning level, verbose or not. */
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if (!__libc_enable_secure
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&& memcmp (envline, "WARN", 4) == 0)
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if (memcmp (envline, "WARN", 4) == 0)
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GLRO(dl_verbose) = envline[5] != '\0';
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break;
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case 5:
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/* Debugging of the dynamic linker? */
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if (!__libc_enable_secure
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&& memcmp (envline, "DEBUG", 5) == 0)
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if (memcmp (envline, "DEBUG", 5) == 0)
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{
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process_dl_debug (state, &envline[6]);
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break;
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@ -2579,8 +2637,7 @@ process_envvars (struct dl_main_state *state)
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case 7:
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/* Print information about versions. */
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if (!__libc_enable_secure
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&& memcmp (envline, "VERBOSE", 7) == 0)
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if (memcmp (envline, "VERBOSE", 7) == 0)
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{
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state->version_info = envline[8] != '\0';
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break;
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@ -2597,43 +2654,37 @@ process_envvars (struct dl_main_state *state)
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}
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/* Which shared object shall be profiled. */
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if (!__libc_enable_secure
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&& memcmp (envline, "PROFILE", 7) == 0 && envline[8] != '\0')
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if (memcmp (envline, "PROFILE", 7) == 0 && envline[8] != '\0')
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GLRO(dl_profile) = &envline[8];
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break;
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case 8:
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/* Do we bind early? */
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if (!__libc_enable_secure
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&& memcmp (envline, "BIND_NOW", 8) == 0)
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if (memcmp (envline, "BIND_NOW", 8) == 0)
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{
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GLRO(dl_lazy) = envline[9] == '\0';
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break;
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}
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if (! __libc_enable_secure
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&& memcmp (envline, "BIND_NOT", 8) == 0)
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if (memcmp (envline, "BIND_NOT", 8) == 0)
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GLRO(dl_bind_not) = envline[9] != '\0';
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break;
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case 9:
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/* Test whether we want to see the content of the auxiliary
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array passed up from the kernel. */
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if (!__libc_enable_secure
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&& memcmp (envline, "SHOW_AUXV", 9) == 0)
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if (memcmp (envline, "SHOW_AUXV", 9) == 0)
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_dl_show_auxv ();
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break;
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case 11:
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/* Path where the binary is found. */
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if (!__libc_enable_secure
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&& memcmp (envline, "ORIGIN_PATH", 11) == 0)
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if (memcmp (envline, "ORIGIN_PATH", 11) == 0)
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GLRO(dl_origin_path) = &envline[12];
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break;
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case 12:
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/* The library search path. */
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if (!__libc_enable_secure
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&& memcmp (envline, "LIBRARY_PATH", 12) == 0)
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if (memcmp (envline, "LIBRARY_PATH", 12) == 0)
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{
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state->library_path = &envline[13];
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state->library_path_source = "LD_LIBRARY_PATH";
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@ -2641,30 +2692,26 @@ process_envvars (struct dl_main_state *state)
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}
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/* Where to place the profiling data file. */
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if (!__libc_enable_secure
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&& memcmp (envline, "DEBUG_OUTPUT", 12) == 0)
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if (memcmp (envline, "DEBUG_OUTPUT", 12) == 0)
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{
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debug_output = &envline[13];
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break;
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}
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if (!__libc_enable_secure
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&& memcmp (envline, "DYNAMIC_WEAK", 12) == 0)
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if (memcmp (envline, "DYNAMIC_WEAK", 12) == 0)
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GLRO(dl_dynamic_weak) = 1;
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break;
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case 14:
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/* Where to place the profiling data file. */
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if (!__libc_enable_secure
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&& memcmp (envline, "PROFILE_OUTPUT", 14) == 0
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if (memcmp (envline, "PROFILE_OUTPUT", 14) == 0
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&& envline[15] != '\0')
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GLRO(dl_profile_output) = &envline[15];
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break;
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case 20:
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/* The mode of the dynamic linker can be set. */
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if (!__libc_enable_secure
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&& memcmp (envline, "TRACE_LOADED_OBJECTS", 20) == 0)
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if (memcmp (envline, "TRACE_LOADED_OBJECTS", 20) == 0)
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{
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state->mode = rtld_mode_trace;
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state->mode_trace_program
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@ -2674,30 +2721,10 @@ process_envvars (struct dl_main_state *state)
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}
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}
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/* Extra security for SUID binaries. Remove all dangerous environment
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variables. */
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if (__glibc_unlikely (__libc_enable_secure))
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{
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const char *nextp = UNSECURE_ENVVARS;
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do
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{
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unsetenv (nextp);
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nextp = strchr (nextp, '\0') + 1;
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}
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while (*nextp != '\0');
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if (GLRO(dl_debug_mask) != 0
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|| GLRO(dl_verbose) != 0
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|| GLRO(dl_lazy) != 1
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|| GLRO(dl_bind_not) != 0
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|| state->mode != rtld_mode_normal
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|| state->version_info)
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_exit (5);
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}
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/* If we have to run the dynamic linker in debugging mode and the
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LD_DEBUG_OUTPUT environment variable is given, we write the debug
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messages to this file. */
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else if (GLRO(dl_debug_mask) != 0 && debug_output != NULL)
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if (GLRO(dl_debug_mask) != 0 && debug_output != NULL)
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{
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const int flags = O_WRONLY | O_APPEND | O_CREAT | O_NOFOLLOW;
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size_t name_len = strlen (debug_output);
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@ -2716,6 +2743,15 @@ process_envvars (struct dl_main_state *state)
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}
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}
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static void
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process_envvars (struct dl_main_state *state)
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{
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if (__glibc_unlikely (__libc_enable_secure))
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process_envvars_secure (state);
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else
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process_envvars_default (state);
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}
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#if HP_TIMING_INLINE
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static void
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print_statistics_item (const char *title, hp_timing_t time,
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