From: J. R. Okajima Date: Sun, 7 Feb 2010 06:48:55 +0000 (+1100) Subject: ima: fix null pointer deref X-Git-Url: http://git.kernel.org/?p=linux%2Fkernel%2Fgit%2Fjmorris%2Fsecurity-testing-2.6.git;a=commitdiff_plain;h=8bb6795424b09db0eca1cccf7a17b93fc28ac7f7 ima: fix null pointer deref 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 Signed-off-by: James Morris --- 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;