Replace pid_t in autofs with struct pid reference
Make autofs container-friendly by caching struct pid reference rather than
pid_t and using pid_nr() to retreive a task's pid_t.
ChangeLog:
- Fix Eric Biederman's comments - Use find_get_pid() to hold a
reference to oz_pgrp and release while unmounting; separate out
changes to autofs and autofs4.
- Fix Cedric's comments: retain old prototype of parse_options()
and move necessary change to its caller.
Signed-off-by: Sukadev Bhattiprolu <sukadev@us.ibm.com>
Cc: Cedric Le Goater <clg@fr.ibm.com>
Cc: Dave Hansen <haveblue@us.ibm.com>
Cc: Serge Hallyn <serue@us.ibm.com>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: containers@lists.osdl.org
Acked-by: Eric W. Biederman <ebiederm@xmission.com>
Cc: Ian Kent <raven@themaw.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/fs/autofs/inode.c b/fs/autofs/inode.c
index d8315e6..e7204d7 100644
--- a/fs/autofs/inode.c
+++ b/fs/autofs/inode.c
@@ -37,6 +37,8 @@
if (!sbi->catatonic)
autofs_catatonic_mode(sbi); /* Free wait queues, close pipe */
+ put_pid(sbi->oz_pgrp);
+
autofs_hash_nuke(sbi);
for (n = 0; n < AUTOFS_MAX_SYMLINKS; n++) {
if (test_bit(n, sbi->symlink_bitmap))
@@ -139,6 +141,7 @@
int pipefd;
struct autofs_sb_info *sbi;
int minproto, maxproto;
+ pid_t pgid;
sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
if (!sbi)
@@ -150,7 +153,6 @@
sbi->pipe = NULL;
sbi->catatonic = 1;
sbi->exp_timeout = 0;
- sbi->oz_pgrp = process_group(current);
autofs_initialize_hash(&sbi->dirhash);
sbi->queues = NULL;
memset(sbi->symlink_bitmap, 0, sizeof(long)*AUTOFS_SYMLINK_BITMAP_LEN);
@@ -171,7 +173,7 @@
/* Can this call block? - WTF cares? s is locked. */
if (parse_options(data, &pipefd, &root_inode->i_uid,
- &root_inode->i_gid, &sbi->oz_pgrp, &minproto,
+ &root_inode->i_gid, &pgid, &minproto,
&maxproto)) {
printk("autofs: called with bogus options\n");
goto fail_dput;
@@ -184,13 +186,21 @@
goto fail_dput;
}
- DPRINTK(("autofs: pipe fd = %d, pgrp = %u\n", pipefd, sbi->oz_pgrp));
+ DPRINTK(("autofs: pipe fd = %d, pgrp = %u\n", pipefd, pgid));
+ sbi->oz_pgrp = find_get_pid(pgid);
+
+ if (!sbi->oz_pgrp) {
+ printk("autofs: could not find process group %d\n", pgid);
+ goto fail_dput;
+ }
+
pipe = fget(pipefd);
if (!pipe) {
printk("autofs: could not open pipe file descriptor\n");
- goto fail_dput;
+ goto fail_put_pid;
}
+
if (!pipe->f_op || !pipe->f_op->write)
goto fail_fput;
sbi->pipe = pipe;
@@ -205,6 +215,8 @@
fail_fput:
printk("autofs: pipe file descriptor does not contain proper ops\n");
fput(pipe);
+fail_put_pid:
+ put_pid(sbi->oz_pgrp);
fail_dput:
dput(root);
goto fail_free;