Quoting Tycho Andersen (tycho.ander...@canonical.com): > 1. prctl() only accepts longs, so we can just scan the stat file as longs.
? That's not what the manpage tells me. > 2. check overflow before addition > > Signed-off-by: Tycho Andersen <tycho.ander...@canonical.com> > --- > src/lxc/utils.c | 18 ++++++++++++------ > 1 file changed, 12 insertions(+), 6 deletions(-) > > diff --git a/src/lxc/utils.c b/src/lxc/utils.c > index 1df6e8f..cc12ecd 100644 > --- a/src/lxc/utils.c > +++ b/src/lxc/utils.c > @@ -1599,7 +1599,7 @@ int setproctitle(char *title) > char buf[2048], *tmp; > FILE *f; > int i, len, ret = 0; > - unsigned long arg_start, arg_end, env_start, env_end; > + long arg_start, arg_end, env_start, env_end; > > f = fopen_cloexec("/proc/self/stat", "r"); > if (!f) { > @@ -1624,7 +1624,7 @@ int setproctitle(char *title) > if (!tmp) > return -1; > > - i = sscanf(tmp, "%lu %lu %lu %lu", &arg_start, &arg_end, &env_start, > &env_end); > + i = sscanf(tmp, "%ld %ld %ld %ld", &arg_start, &arg_end, &env_start, > &env_end); > if (i != 4) { > return -1; > } > @@ -1644,15 +1644,21 @@ int setproctitle(char *title) > if (len >= arg_end - arg_start) { > env_start = env_end; > } > + > + /* check overflow */ > + if (arg_start + len < 0) { > + return -1; > + } > + > arg_end = arg_start + len; > } > > strcpy((char*)arg_start, title); > > - ret |= prctl(PR_SET_MM, PR_SET_MM_ARG_START, (long)arg_start, 0, 0); > - ret |= prctl(PR_SET_MM, PR_SET_MM_ARG_END, (long)arg_end, 0, 0); > - ret |= prctl(PR_SET_MM, PR_SET_MM_ENV_START, (long)env_start, 0, 0); > - ret |= prctl(PR_SET_MM, PR_SET_MM_ENV_END, (long)env_end, 0, 0); > + ret |= prctl(PR_SET_MM, PR_SET_MM_ARG_START, arg_start, 0, 0); > + ret |= prctl(PR_SET_MM, PR_SET_MM_ARG_END, arg_end, 0, 0); > + ret |= prctl(PR_SET_MM, PR_SET_MM_ENV_START, env_start, 0, 0); > + ret |= prctl(PR_SET_MM, PR_SET_MM_ENV_END, env_end, 0, 0); > > return ret; > } > -- > 2.1.4 > > _______________________________________________ > lxc-devel mailing list > lxc-devel@lists.linuxcontainers.org > http://lists.linuxcontainers.org/listinfo/lxc-devel _______________________________________________ lxc-devel mailing list lxc-devel@lists.linuxcontainers.org http://lists.linuxcontainers.org/listinfo/lxc-devel