From: Paulo Alcantara <pc@xxxxxxxxxxxxx>
[ Upstream commit ca545b7f0823f19db0f1148d59bc5e1a56634502 ]
Skip sessions that are being teared down (status == SES_EXITING) to
avoid UAF.
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Paulo Alcantara (Red Hat) <pc@xxxxxxxxxxxxx>
Signed-off-by: Steve French <stfrench@xxxxxxxxxxxxx>
[This patch removes lock/unlock operation in routine cifs_ses_exiting()
for ses_lock is not present in v5.15 and not ported yet. ses->status
is protected by a global lock, cifs_tcp_ses_lock, in v5.15.]
Signed-off-by: Jianqi Ren <jianqi.ren.cn@xxxxxxxxxxxxx>
Signed-off-by: He Zhe <zhe.he@xxxxxxxxxxxxx>
---
Verified the build test
---
fs/cifs/cifs_debug.c | 2 ++
fs/cifs/cifsglob.h | 8 ++++++++
2 files changed, 10 insertions(+)
diff --git a/fs/cifs/cifs_debug.c b/fs/cifs/cifs_debug.c
index e7501533c2ec..8eb91bd18439 100644
--- a/fs/cifs/cifs_debug.c
+++ b/fs/cifs/cifs_debug.c
@@ -183,6 +183,8 @@ static int cifs_debug_files_proc_show(struct seq_file *m, void *v)
list_for_each_entry(server, &cifs_tcp_ses_list, tcp_ses_list) {
list_for_each(tmp, &server->smb_ses_list) {
ses = list_entry(tmp, struct cifs_ses, smb_ses_list);
+ if (cifs_ses_exiting(ses))
+ continue;
list_for_each(tmp1, &ses->tcon_list) {
tcon = list_entry(tmp1, struct cifs_tcon, tcon_list);
spin_lock(&tcon->open_file_lock);
diff --git a/fs/cifs/cifsglob.h b/fs/cifs/cifsglob.h
index 2ee67a27020d..7b57cc5d7022 100644
--- a/fs/cifs/cifsglob.h
+++ b/fs/cifs/cifsglob.h
@@ -2041,4 +2041,12 @@ static inline struct scatterlist *cifs_sg_set_buf(struct scatterlist *sg,
return sg;
}
+static inline bool cifs_ses_exiting(struct cifs_ses *ses)
+{
+ bool ret;
+
+ ret = ses->status == CifsExiting;
+ return ret;
+}
+
#endif /* _CIFS_GLOB_H */
--
2.25.1
