Merge branch 'tr/protect-low-3-fds'

When "git" is spawned in such a way that any of the low 3 file
descriptors is closed, our first open() may yield file descriptor 2,
and writing error message to it would screw things up in a big way.

* tr/protect-low-3-fds:
  git: ensure 0/1/2 are open in main()
  daemon/shell: refactor redirection of 0/1/2 from /dev/null
This commit is contained in:
Junio C Hamano
2013-07-22 11:23:35 -07:00
5 changed files with 24 additions and 21 deletions

12
shell.c
View File

@ -147,7 +147,6 @@ int main(int argc, char **argv)
char *prog;
const char **user_argv;
struct commands *cmd;
int devnull_fd;
int count;
git_setup_gettext();
@ -156,15 +155,10 @@ int main(int argc, char **argv)
/*
* Always open file descriptors 0/1/2 to avoid clobbering files
* in die(). It also avoids not messing up when the pipes are
* dup'ed onto stdin/stdout/stderr in the child processes we spawn.
* in die(). It also avoids messing up when the pipes are dup'ed
* onto stdin/stdout/stderr in the child processes we spawn.
*/
devnull_fd = open("/dev/null", O_RDWR);
while (devnull_fd >= 0 && devnull_fd <= 2)
devnull_fd = dup(devnull_fd);
if (devnull_fd == -1)
die_errno("opening /dev/null failed");
close (devnull_fd);
sanitize_stdfds();
/*
* Special hack to pretend to be a CVS server