diff options
Diffstat (limited to 'sys/kern')
| -rw-r--r-- | sys/kern/sys_pipe.c | 8 |
1 files changed, 8 insertions, 0 deletions
diff --git a/sys/kern/sys_pipe.c b/sys/kern/sys_pipe.c index 4c505e7..3b944dd 100644 --- a/sys/kern/sys_pipe.c +++ b/sys/kern/sys_pipe.c @@ -182,6 +182,12 @@ pipe(p, uap) pipeinit(wpipe); wpipe->pipe_state |= PIPE_DIRECTOK; + /* + * Warning: once we've gotten past allocation of the fd for the + * read-side, we can only drop the read side via fdrop() in order + * to avoid races against processes which manage to dup() the read + * side while we are blocked trying to allocate the write side. + */ error = falloc(p, &rf, &fd); if (error) goto free2; @@ -211,6 +217,8 @@ free3: fdrop(rf, p); } fdrop(rf, p); + /* rpipe has been closed by fdrop() */ + rpipe = NULL; free2: (void)pipeclose(wpipe); (void)pipeclose(rpipe); |
