diff options
Diffstat (limited to 'libmudflap/mf-runtime.c')
| -rw-r--r-- | libmudflap/mf-runtime.c | 13 |
1 files changed, 11 insertions, 2 deletions
diff --git a/libmudflap/mf-runtime.c b/libmudflap/mf-runtime.c index 3bfaf02b6a0..08a50c21807 100644 --- a/libmudflap/mf-runtime.c +++ b/libmudflap/mf-runtime.c @@ -303,6 +303,14 @@ __mf_set_default_options () #ifdef LIBMUDFLAPTH __mf_opts.thread_stack = 0; #endif + + /* PR41443: Beware that the above flags will be applied to + setuid/setgid binaries, and cannot be overriden with + $MUDFLAP_OPTIONS. So the defaults must be non-exploitable. + + Should we consider making the default violation_mode something + harsher than viol_nop? OTOH, glibc's MALLOC_CHECK_ is disabled + by default for these same programs. */ } static struct mudoption @@ -442,7 +450,7 @@ __mf_usage () "This is a %s%sGCC \"mudflap\" memory-checked binary.\n" "Mudflap is Copyright (C) 2002-2009 Free Software Foundation, Inc.\n" "\n" - "The mudflap code can be controlled by an environment variable:\n" + "Unless setuid, a program's mudflap options be set by an environment variable:\n" "\n" "$ export MUDFLAP_OPTIONS='<options>'\n" "$ <mudflapped_program>\n" @@ -711,7 +719,8 @@ __mf_init () __mf_set_default_options (); - ov = getenv ("MUDFLAP_OPTIONS"); + if (getuid () == geteuid () && getgid () == getegid ()) /* PR41433, not setuid */ + ov = getenv ("MUDFLAP_OPTIONS"); if (ov) { int rc = __mfu_set_options (ov); |