[PATCH] pipe, call path_put() after put_filp() in the error path

From: J. R. Okajima
Date: Tue Dec 29 2009 - 00:46:15 EST


The commit 6c21a7f "LSM: imbed ima calls in the security hooks"
which moves the ima_file_free() call within security_file_free()
brought a problem into pipe.c.
In the error path of pipe(2), the allocated resources are freed by
path_put() and put_filp() (in this order). Since security_file_free()
refers f_dentry and ima_file_free() refers f_dentry->d_inode, path_put()
should be called after put_filp().

Signed-off-by: J. R. Okajima <hooanon05@xxxxxxxxxxx>
---
fs/pipe.c | 7 +++++--
1 files changed, 5 insertions(+), 2 deletions(-)

diff --git a/fs/pipe.c b/fs/pipe.c
index 37ba29f..90b543d 100644
--- a/fs/pipe.c
+++ b/fs/pipe.c
@@ -1004,9 +1004,10 @@ struct file *create_write_pipe(int flags)

void free_write_pipe(struct file *f)
{
+ struct path path = f->f_path;
free_pipe_info(f->f_dentry->d_inode);
- path_put(&f->f_path);
put_filp(f);
+ path_put(&path);
}

struct file *create_read_pipe(struct file *wrf, int flags)
@@ -1028,6 +1029,7 @@ int do_pipe_flags(int *fd, int flags)
struct file *fw, *fr;
int error;
int fdw, fdr;
+ struct path path;

if (flags & ~(O_CLOEXEC | O_NONBLOCK))
return -EINVAL;
@@ -1061,8 +1063,9 @@ int do_pipe_flags(int *fd, int flags)
err_fdr:
put_unused_fd(fdr);
err_read_pipe:
- path_put(&fr->f_path);
+ path = fr->f_path;
put_filp(fr);
+ path_put(&path);
err_write_pipe:
free_write_pipe(fw);
return error;
--
1.6.1.284.g5dc13

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