From: Alexander Monakov <amonakov@ispras.ru>
To: musl@lists.openwall.com
Subject: [PATCH] __init_libc: add fallbacks for __progname setup
Date: Fri, 28 Jul 2017 17:46:49 +0300 [thread overview]
Message-ID: <20170728144649.3440-1-amonakov@ispras.ru> (raw)
It is possible for argv[0] to be a null pointer, but the __progname
variable is used to implement functions in src/legacy/err.c that do not
expect it to be null. It is also available to the user via the
program_invocation_name alias as a GNU extension, and the implementation
in Glibc initializes it to a pointer to empty string rather than NULL.
Since argv[0] is usually non-null and it's preferable to keep those
variables in BSS, implement the fallbacks in __init_libc, which also
allows to have an intermediate fallback to AT_EXECFN.
---
src/env/__libc_start_main.c | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)
diff --git a/src/env/__libc_start_main.c b/src/env/__libc_start_main.c
index 5c79be28..18afdc1d 100644
--- a/src/env/__libc_start_main.c
+++ b/src/env/__libc_start_main.c
@@ -30,10 +30,10 @@ void __init_libc(char **envp, char *pn)
__sysinfo = aux[AT_SYSINFO];
libc.page_size = aux[AT_PAGESZ];
- if (pn) {
- __progname = __progname_full = pn;
- for (i=0; pn[i]; i++) if (pn[i]=='/') __progname = pn+i+1;
- }
+ if (!pn) pn = (void*)aux[AT_EXECFN];
+ if (!pn) pn = "";
+ __progname = __progname_full = pn;
+ for (i=0; pn[i]; i++) if (pn[i]=='/') __progname = pn+i+1;
__init_tls(aux);
__init_ssp((void *)aux[AT_RANDOM]);
--
2.11.0
reply other threads:[~2017-07-28 14:46 UTC|newest]
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