[PATCH v18 61/80] c/r: restore file->f_cred

Oren Laadan
2009-09-24T00:37:10Z

From: Serge E. Hallyn <serue@us.ibm.com>

Restore a file's f_cred. This is set to the cred of the task doing
the open, so often it will be the same as that of the restarted task.

Changelog[v1]:
- [Nathan Lynch] discard const from struct cred * where appropriate

Signed-off-by: Serge E. Hallyn <serue@us.ibm.com>
---
checkpoint/files.c | 18 ++++++++++++++++--
include/linux/checkpoint_hdr.h | 2 +-
2 files changed, 17 insertions(+), 3 deletions(-)

diff --git a/checkpoint/files.c b/checkpoint/files.c
index 190c95b..1de89d6 100644
--- a/checkpoint/files.c
+++ b/checkpoint/files.c
@@ -147,12 +147,18 @@ static int scan_fds(struct files_struct *files, int **fdtable)
int checkpoint_file_common(struct ckpt_ctx *ctx, struct file *file,
struct ckpt_hdr_file *h)
{
+ struct cred *f_cred = (struct cred *) file->f_cred;
+
h->f_flags = file->f_flags;
h->f_mode = file->f_mode;
h->f_pos = file->f_pos;
h->f_version = file->f_version;

- /* FIX: need also file->uid, file->gid, file->f_owner, etc */
+ h->f_credref = checkpoint_obj(ctx, f_cred, CKPT_OBJ_CRED);
+ if (h->f_credref < 0)
+ return h->f_credref;
+
+ /* FIX: need also file->f_owner, etc */

return 0;
}
@@ -489,8 +495,16 @@ int restore_file_common(struct ckpt_ctx *ctx, struct file *file,
fmode_t new_mode = file->f_mode;
fmode_t saved_mode = (__force fmode_t) h->f_mode;
int ret;
+ struct cred *cred;
+
+ /* FIX: need to restore owner etc */

- /* FIX: need to restore uid, gid, owner etc */
+ /* restore the cred */
+ cred = ckpt_obj_fetch(ctx, h->f_credref, CKPT_OBJ_CRED);
+ if (IS_ERR(cred))
+ return PTR_ERR(cred);
+ put_cred(file->f_cred);
+ file->f_cred = get_cred(cred);

/* safe to set 1st arg (fd) to 0, as command is F_SETFL */
ret = vfs_fcntl(0, F_SETFL, h->f_flags & CKPT_SETFL_MASK, file);
diff --git a/include/linux/checkpoint_hdr.h b/include/linux/checkpoint_hdr.h
index 3f00bce..ca24112 100644
--- a/include/linux/checkpoint_hdr.h
+++ b/include/linux/checkpoint_hdr.h
@@ -350,7 +350,7 @@ struct ckpt_hdr_file {
__u32 f_type;
__u32 f_mode;
__u32 f_flags;
- __u32 _padding;
+ __s32 f_credref;
__u64 f_pos;
__u64 f_version;
} __attribute__((aligned(8)));
--
1.6.0.4