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| author | Jamie Bainbridge <jamie.bainbridge@gmail.com> | 2021-09-08 12:08:17 +1000 |
|---|---|---|
| committer | Michael Catanzaro <mcatanzaro@redhat.com> | 2022-01-27 10:14:14 -0600 |
| commit | ffc00caa7391e602fd1ee18f2b1522b313942b05 (patch) | |
| tree | 580965a51519a70f59e2a71a58749118931d1657 | |
| parent | 63d0e9750e16e62b1c928ba15eac22cb9d03ed43 (diff) | |
| download | glib-ffc00caa7391e602fd1ee18f2b1522b313942b05.tar.gz | |
gutils: Avoid segfault in g_get_user_database_entry
g_get_user_database_entry() uses variable pwd to store the contents of
the call to getpwnam_r(), then capitalises the first letter of pw_name
with g_ascii_toupper (pw->pw_name[0]).
However, as per the getpwnam manpage, the result of that call "may point
to a static area". When this happens, GLib is trying to edit static
memory which belongs to a shared library, so segfaults.
Instead, copy pw_name off to a temporary variable, set uppercase on
that variable, and use the variable to join into the desired string.
Free the new variable after it is no longer needed.
Signed-off-by: Jamie Bainbridge <jamie.bainbridge@gmail.com>
| -rw-r--r-- | glib/gutils.c | 7 |
1 files changed, 5 insertions, 2 deletions
diff --git a/glib/gutils.c b/glib/gutils.c index dad162528..7503c09ea 100644 --- a/glib/gutils.c +++ b/glib/gutils.c @@ -685,14 +685,17 @@ g_get_user_database_entry (void) { gchar **gecos_fields; gchar **name_parts; + gchar *uppercase_pw_name; /* split the gecos field and substitute '&' */ gecos_fields = g_strsplit (pw->pw_gecos, ",", 0); name_parts = g_strsplit (gecos_fields[0], "&", 0); - pw->pw_name[0] = g_ascii_toupper (pw->pw_name[0]); - e.real_name = g_strjoinv (pw->pw_name, name_parts); + uppercase_pw_name = g_strdup (pw->pw_name); + uppercase_pw_name[0] = g_ascii_toupper (uppercase_pw_name[0]); + e.real_name = g_strjoinv (uppercase_pw_name, name_parts); g_strfreev (gecos_fields); g_strfreev (name_parts); + g_free (uppercase_pw_name); } #endif |