Merge v7.2.4linux-rolling-stable

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

8 files changed, 99 insertions, 23 deletions

diff --git a/security/apparmor/include/cred.h b/security/apparmor/include/cred.h
index 2b6098149b15..0e8b67159f56 100644
--- a/security/apparmor/include/cred.h
+++ b/security/apparmor/include/cred.h
@@ -222,13 +222,9 @@ static inline struct aa_label *begin_current_label_crit_section(void)
 {
 	struct aa_label *label = aa_current_raw_label();
 
-	might_sleep();
-
 	if (label_is_stale(label)) {
 		label = aa_get_newest_label(label);
-		if (aa_replace_current_label(label) == 0)
-			/* task cred will keep the reference */
-			aa_put_label(label);
+		aa_schedule_stale_label_replacement();
 	}
 
 	return label;
diff --git a/security/apparmor/include/label.h b/security/apparmor/include/label.h
index b5a722a47fd2..37cb135de323 100644
--- a/security/apparmor/include/label.h
+++ b/security/apparmor/include/label.h
@@ -23,7 +23,7 @@ struct aa_ruleset;
 
 #define LOCAL_VEC_ENTRIES 8
 #define DEFINE_VEC(T, V)						\
-	struct aa_ ## T *(_ ## V ## _localtmp)[LOCAL_VEC_ENTRIES];	\
+	struct aa_ ## T *(_ ## V ## _localtmp)[LOCAL_VEC_ENTRIES + 1];	\
 	struct aa_ ## T **(V)
 
 #define vec_setup(T, V, N, GFP)						\
@@ -31,10 +31,10 @@ struct aa_ruleset;
 	if ((N) <= LOCAL_VEC_ENTRIES) {					\
 		typeof(N) i;						\
 		(V) = (_ ## V ## _localtmp);				\
-		for (i = 0; i < (N); i++)				\
+		for (i = 0; i <= (N); i++)				\
 			(V)[i] = NULL;					\
 	} else								\
-		(V) = kzalloc(sizeof(struct aa_ ## T *) * (N), (GFP));	\
+		(V) = kzalloc_objs(struct aa_ ## T *, (N) + 1, (GFP));	\
 	(V) ? 0 : -ENOMEM;						\
 })
 
diff --git a/security/apparmor/include/task.h b/security/apparmor/include/task.h
index b1aaaf60fa8b..6f26758ca10f 100644
--- a/security/apparmor/include/task.h
+++ b/security/apparmor/include/task.h
@@ -21,15 +21,22 @@ static inline struct aa_task_ctx *task_ctx(struct task_struct *task)
  * @onexec: profile to transition to on next exec  (MAY BE NULL)
  * @previous: profile the task may return to     (MAY BE NULL)
  * @token: magic value the task must know for returning to @previous_profile
+ * @label_replacement_tw: for aa_schedule_stale_label_replacement()
+ * @label_replacement_pending: is @label_replacement_tw pending?
+ *
+ * When changing this, check if aa_dup_task_ctx() needs to be updated.
  */
 struct aa_task_ctx {
 	struct aa_label *nnp;
 	struct aa_label *onexec;
 	struct aa_label *previous;
 	u64 token;
+	struct callback_head label_replacement_tw;
+	bool label_replacement_pending;
 };
 
 int aa_replace_current_label(struct aa_label *label);
+void aa_schedule_stale_label_replacement(void);
 void aa_set_current_onexec(struct aa_label *label, bool stack);
 int aa_set_current_hat(struct aa_label *label, u64 token);
 int aa_restore_previous_label(u64 cookie);
@@ -56,10 +63,10 @@ static inline void aa_free_task_ctx(struct aa_task_ctx *ctx)
 static inline void aa_dup_task_ctx(struct aa_task_ctx *new,
 				   const struct aa_task_ctx *old)
 {
-	*new = *old;
-	aa_get_label(new->nnp);
-	aa_get_label(new->previous);
-	aa_get_label(new->onexec);
+	new->nnp = aa_get_label(old->nnp);
+	new->onexec = aa_get_label(old->onexec);
+	new->previous = aa_get_label(old->previous);
+	new->token = old->token;
 }
 
 /**
diff --git a/security/apparmor/task.c b/security/apparmor/task.c
index b9fb3738124e..e16ff4130bc2 100644
--- a/security/apparmor/task.c
+++ b/security/apparmor/task.c
@@ -14,6 +14,7 @@
 
 #include <linux/gfp.h>
 #include <linux/ptrace.h>
+#include <linux/task_work.h>
 
 #include "include/path.h"
 #include "include/audit.h"
@@ -89,6 +90,32 @@ int aa_replace_current_label(struct aa_label *label)
 	return 0;
 }
 
+static void aa_replace_stale_label_tw_func(struct callback_head *tw)
+{
+	struct aa_task_ctx *ctx = task_ctx(current);
+	struct aa_label *label;
+
+	ctx->label_replacement_pending = false;
+	label = aa_current_raw_label();
+	if (!label_is_stale(label))
+		return;
+	label = aa_get_newest_label(label);
+	aa_replace_current_label(label);
+	aa_put_label(label);
+}
+
+/* replace the current task's stale label on syscall return */
+void aa_schedule_stale_label_replacement(void)
+{
+	struct aa_task_ctx *ctx = task_ctx(current);
+
+	if (ctx->label_replacement_pending)
+		return;
+	init_task_work(&ctx->label_replacement_tw, aa_replace_stale_label_tw_func);
+	if (task_work_add(current, &ctx->label_replacement_tw, TWA_RESUME) == 0)
+		ctx->label_replacement_pending = true;
+}
+
 
 /**
  * aa_set_current_onexec - set the tasks change_profile to happen onexec
diff --git a/security/keys/trusted-keys/trusted_tpm1.c b/security/keys/trusted-keys/trusted_tpm1.c
index 13513819991e..8f57c6111e7e 100644
--- a/security/keys/trusted-keys/trusted_tpm1.c
+++ b/security/keys/trusted-keys/trusted_tpm1.c
@@ -987,9 +987,9 @@ err_put:
 static void trusted_tpm_exit(void)
 {
 	if (chip) {
+		unregister_key_type(&key_type_trusted);
 		put_device(&chip->dev);
 		kfree(digests);
-		unregister_key_type(&key_type_trusted);
 	}
 }
 
diff --git a/security/landlock/errata/abi-1.h b/security/landlock/errata/abi-1.h
index 3f099555f059..315ea7e0fe50 100644
--- a/security/landlock/errata/abi-1.h
+++ b/security/landlock/errata/abi-1.h
@@ -22,3 +22,26 @@
  * from their original mount points.
  */
 LANDLOCK_ERRATUM(3)
+
+/**
+ * DOC: erratum_4
+ *
+ * Erratum 4: Creation of whiteout objects
+ * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ *
+ * This fix changes the access rights required for the creation of whiteout
+ * objects through :manpage:`mknod(2)`, :manpage:`renameat2(2)`, or
+ * :manpage:`link(2)`.  Creating whiteout objects is now guarded by
+ * ``LANDLOCK_ACCESS_FS_MAKE_REG`` instead of ``LANDLOCK_ACCESS_FS_MAKE_CHAR``.
+ *
+ * Whiteout objects are used in OverlayFS to mark the absence of a file in an
+ * upper file system.  Despite being created with ``S_IFCHR``, whiteout objects
+ * do not count as character devices.
+ *
+ * Impact:
+ *
+ * Sandboxed programs that create OverlayFS whiteouts (such as fuse-overlayfs)
+ * now require ``LANDLOCK_ACCESS_FS_MAKE_REG`` instead of
+ * ``LANDLOCK_ACCESS_FS_MAKE_CHAR``.
+ */
+LANDLOCK_ERRATUM(4)
diff --git a/security/landlock/fs.c b/security/landlock/fs.c
index f7e5e4ef9eac..8fc7f82a374a 100644
--- a/security/landlock/fs.c
+++ b/security/landlock/fs.c
@@ -20,6 +20,7 @@
 #include <linux/falloc.h>
 #include <linux/fs.h>
 #include <linux/init.h>
+#include <linux/kdev_t.h>
 #include <linux/kernel.h>
 #include <linux/limits.h>
 #include <linux/list.h>
@@ -983,7 +984,8 @@ static int current_check_access_path(const struct path *const path,
 	return -EACCES;
 }
 
-static __attribute_const__ access_mask_t get_mode_access(const umode_t mode)
+static __attribute_const__ access_mask_t get_mode_access(const umode_t mode,
+							 const dev_t dev)
 {
 	switch (mode & S_IFMT) {
 	case S_IFLNK:
@@ -991,6 +993,9 @@ static __attribute_const__ access_mask_t get_mode_access(const umode_t mode)
 	case S_IFDIR:
 		return LANDLOCK_ACCESS_FS_MAKE_DIR;
 	case S_IFCHR:
+		/* Whiteout objects are guarded with MAKE_REG. */
+		if (dev == WHITEOUT_DEV)
+			return LANDLOCK_ACCESS_FS_MAKE_REG;
 		return LANDLOCK_ACCESS_FS_MAKE_CHAR;
 	case S_IFBLK:
 		return LANDLOCK_ACCESS_FS_MAKE_BLOCK;
@@ -1007,6 +1012,13 @@ static __attribute_const__ access_mask_t get_mode_access(const umode_t mode)
 	}
 }
 
+static access_mask_t get_dentry_access(const struct dentry *const dentry)
+{
+	const struct inode *const inode = d_backing_inode(dentry);
+
+	return get_mode_access(inode->i_mode, inode->i_rdev);
+}
+
 static access_mask_t maybe_remove(const struct dentry *const dentry)
 {
 	if (d_is_negative(dentry))
@@ -1093,6 +1105,7 @@ static bool collect_domain_accesses(const struct landlock_ruleset *const domain,
  * @new_dentry: Destination file or directory.
  * @removable: Sets to true if it is a rename operation.
  * @exchange: Sets to true if it is a rename operation with RENAME_EXCHANGE.
+ * @whiteout: Sets to true if it is a rename operation with RENAME_WHITEOUT.
  *
  * Because of its unprivileged constraints, Landlock relies on file hierarchies
  * (and not only inodes) to tie access rights to files.  Being able to link or
@@ -1140,7 +1153,8 @@ static bool collect_domain_accesses(const struct landlock_ruleset *const domain,
 static int current_check_refer_path(struct dentry *const old_dentry,
 				    const struct path *const new_dir,
 				    struct dentry *const new_dentry,
-				    const bool removable, const bool exchange)
+				    const bool removable, const bool exchange,
+				    const bool whiteout)
 {
 	const struct landlock_cred_security *const subject =
 		landlock_get_applicable_subject(current_cred(), any_fs, NULL);
@@ -1159,18 +1173,25 @@ static int current_check_refer_path(struct dentry *const old_dentry,
 	if (exchange) {
 		if (unlikely(d_is_negative(new_dentry)))
 			return -ENOENT;
-		access_request_parent1 =
-			get_mode_access(d_backing_inode(new_dentry)->i_mode);
+		access_request_parent1 = get_dentry_access(new_dentry);
 	} else {
 		access_request_parent1 = 0;
 	}
-	access_request_parent2 =
-		get_mode_access(d_backing_inode(old_dentry)->i_mode);
+	access_request_parent2 = get_dentry_access(old_dentry);
 	if (removable) {
 		access_request_parent1 |= maybe_remove(old_dentry);
 		access_request_parent2 |= maybe_remove(new_dentry);
 	}
 
+	/*
+	 * In case of renameat2(2) with RENAME_WHITEOUT, a whiteout object is
+	 * created in the source location, so we require an additional access
+	 * right there.
+	 */
+	if (whiteout)
+		access_request_parent1 |=
+			get_mode_access(S_IFCHR | WHITEOUT_MODE, WHITEOUT_DEV);
+
 	/* The mount points are the same for old and new paths, cf. EXDEV. */
 	if (old_dentry->d_parent == new_dir->dentry) {
 		/*
@@ -1520,7 +1541,7 @@ static int hook_path_link(struct dentry *const old_dentry,
 			  struct dentry *const new_dentry)
 {
 	return current_check_refer_path(old_dentry, new_dir, new_dentry, false,
-					false);
+					false, false);
 }
 
 static int hook_path_rename(const struct path *const old_dir,
@@ -1531,7 +1552,8 @@ static int hook_path_rename(const struct path *const old_dir,
 {
 	/* old_dir refers to old_dentry->d_parent and new_dir->mnt */
 	return current_check_refer_path(old_dentry, new_dir, new_dentry, true,
-					!!(flags & RENAME_EXCHANGE));
+					!!(flags & RENAME_EXCHANGE),
+					!!(flags & RENAME_WHITEOUT));
 }
 
 static int hook_path_mkdir(const struct path *const dir,
@@ -1544,7 +1566,8 @@ static int hook_path_mknod(const struct path *const dir,
 			   struct dentry *const dentry, const umode_t mode,
 			   const unsigned int dev)
 {
-	return current_check_access_path(dir, get_mode_access(mode));
+	return current_check_access_path(
+		dir, get_mode_access(mode, new_decode_dev(dev)));
 }
 
 static int hook_path_symlink(const struct path *const dir,
diff --git a/security/smack/smack_lsm.c b/security/smack/smack_lsm.c
index ff115068c5c0..bbe6cd6b03f7 100644
--- a/security/smack/smack_lsm.c
+++ b/security/smack/smack_lsm.c
@@ -1964,7 +1964,7 @@ static int smack_file_send_sigiotask(struct task_struct *tsk,
 {
 	struct smack_known **blob;
 	struct smack_known *skp;
-	struct smack_known *tkp = smk_of_task(smack_cred(tsk->cred));
+	struct smack_known *tkp = smk_of_task_struct_obj(tsk);
 	const struct cred *tcred;
 	struct file *file;
 	int rc;