| Message ID | 20231205141054.1759563-2-smayhew@redhat.com (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | Use parent's objective cred in nfs_access_login_time() | expand |
diff --git a/fs/nfs/dir.c b/fs/nfs/dir.c index 13dffe4201e6..273c0b68abf4 100644 --- a/fs/nfs/dir.c +++ b/fs/nfs/dir.c @@ -2963,7 +2963,7 @@ static u64 nfs_access_login_time(const struct task_struct *task, rcu_read_lock(); for (;;) { parent = rcu_dereference(task->real_parent); - pcred = rcu_dereference(parent->cred); + pcred = __task_cred(parent); if (parent == task || cred_fscmp(pcred, cred) != 0) break; task = parent;
The subjective cred (task->cred) can potentially be overridden and subsquently freed in non-RCU context, which could lead to a panic if we try to use it in cred_fscmp(). Use __task_cred(), which returns the objective cred (task->real_cred) instead. Fixes: 0eb43812c027 ("NFS: Clear the file access cache upon login") Fixes: 5e9a7b9c2ea1 ("NFS: Fix up a sparse warning") Signed-off-by: Scott Mayhew <smayhew@redhat.com> --- fs/nfs/dir.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)