Merge tag 'apparmor-pr-2019-12-03' of...

Merge tag 'apparmor-pr-2019-12-03' of git://git.kernel.org/pub/scm/linux/kernel/git/jj/linux-apparmor

Pull apparmor updates from John Johansen:
 "Features:

   - increase left match history buffer size to provide improved
     conflict resolution in overlapping execution rules.

   - switch buffer allocation to use a memory pool and GFP_KERNEL where
     possible.

   - add compression of policy blobs to reduce memory usage.

  Cleanups:

   - fix spelling mistake "immutible" -> "immutable"

  Bug fixes:

   - fix unsigned len comparison in update_for_len macro

   - fix sparse warning for type-casting of current->real_cred"

* tag 'apparmor-pr-2019-12-03' of git://git.kernel.org/pub/scm/linux/kernel/git/jj/linux-apparmor:
  apparmor: make it so work buffers can be allocated from atomic context
  apparmor: reduce rcu_read_lock scope for aa_file_perm mediation
  apparmor: fix wrong buffer allocation in aa_new_mount
  apparmor: fix unsigned len comparison with less than zero
  apparmor: increase left match history buffer size
  apparmor: Switch to GFP_KERNEL where possible
  apparmor: Use a memory pool instead per-CPU caches
  apparmor: Force type-casting of current->real_cred
  apparmor: fix spelling mistake "immutible" -> "immutable"
  apparmor: fix blob compression when ns is forced on a policy load
  apparmor: fix missing ZLIB defines
  apparmor: fix blob compression build failure on ppc
  apparmor: Initial implementation of raw policy blob compression

security/apparmor/Kconfig

@@ -6,6 +6,8 @@ config SECURITY_APPARMOR
 	select SECURITY_PATH
 	select SECURITYFS
 	select SECURITY_NETWORK
+	select ZLIB_INFLATE
+	select ZLIB_DEFLATE
 	default n
 	help
 	  This enables the AppArmor security module.

security/apparmor/apparmorfs.c

@@ -21,6 +21,7 @@
 #include <linux/fs.h>
 #include <linux/fs_context.h>
 #include <linux/poll.h>
+#include <linux/zlib.h>
 #include <uapi/linux/major.h>
 #include <uapi/linux/magic.h>
 
@@ -65,6 +66,35 @@
  * support fns
  */
 
+struct rawdata_f_data {
+	struct aa_loaddata *loaddata;
+};
+
+#define RAWDATA_F_DATA_BUF(p) (char *)(p + 1)
+
+static void rawdata_f_data_free(struct rawdata_f_data *private)
+{
+	if (!private)
+		return;
+
+	aa_put_loaddata(private->loaddata);
+	kvfree(private);
+}
+
+static struct rawdata_f_data *rawdata_f_data_alloc(size_t size)
+{
+	struct rawdata_f_data *ret;
+
+	if (size > SIZE_MAX - sizeof(*ret))
+		return ERR_PTR(-EINVAL);
+
+	ret = kvzalloc(sizeof(*ret) + size, GFP_KERNEL);
+	if (!ret)
+		return ERR_PTR(-ENOMEM);
+
+	return ret;
+}
+
 /**
  * aa_mangle_name - mangle a profile name to std profile layout form
  * @name: profile name to mangle  (NOT NULL)
@@ -1280,36 +1310,117 @@ static int seq_rawdata_hash_show(struct seq_file *seq, void *v)
 	return 0;
 }
 
+static int seq_rawdata_compressed_size_show(struct seq_file *seq, void *v)
+{
+	struct aa_loaddata *data = seq->private;
+
+	seq_printf(seq, "%zu\n", data->compressed_size);
+
+	return 0;
+}
+
 SEQ_RAWDATA_FOPS(abi);
 SEQ_RAWDATA_FOPS(revision);
 SEQ_RAWDATA_FOPS(hash);
+SEQ_RAWDATA_FOPS(compressed_size);
+
+static int deflate_decompress(char *src, size_t slen, char *dst, size_t dlen)
+{
+	int error;
+	struct z_stream_s strm;
+
+	if (aa_g_rawdata_compression_level == 0) {
+		if (dlen < slen)
+			return -EINVAL;
+		memcpy(dst, src, slen);
+		return 0;
+	}
+
+	memset(&strm, 0, sizeof(strm));
+
+	strm.workspace = kvzalloc(zlib_inflate_workspacesize(), GFP_KERNEL);
+	if (!strm.workspace)
+		return -ENOMEM;
+
+	strm.next_in = src;
+	strm.avail_in = slen;
+
+	error = zlib_inflateInit(&strm);
+	if (error != Z_OK) {
+		error = -ENOMEM;
+		goto fail_inflate_init;
+	}
+
+	strm.next_out = dst;
+	strm.avail_out = dlen;
+
+	error = zlib_inflate(&strm, Z_FINISH);
+	if (error != Z_STREAM_END)
+		error = -EINVAL;
+	else
+		error = 0;
+
+	zlib_inflateEnd(&strm);
+fail_inflate_init:
+	kvfree(strm.workspace);
+	return error;
+}
 
 static ssize_t rawdata_read(struct file *file, char __user *buf, size_t size,
 			    loff_t *ppos)
 {
-	struct aa_loaddata *rawdata = file->private_data;
+	struct rawdata_f_data *private = file->private_data;
 
-	return simple_read_from_buffer(buf, size, ppos, rawdata->data,
-				       rawdata->size);
+	return simple_read_from_buffer(buf, size, ppos,
+				       RAWDATA_F_DATA_BUF(private),
+				       private->loaddata->size);
 }
 
 static int rawdata_release(struct inode *inode, struct file *file)
 {
-	aa_put_loaddata(file->private_data);
+	rawdata_f_data_free(file->private_data);
 
 	return 0;
 }
 
 static int rawdata_open(struct inode *inode, struct file *file)
 {
+	int error;
+	struct aa_loaddata *loaddata;
+	struct rawdata_f_data *private;
+
 	if (!policy_view_capable(NULL))
 		return -EACCES;
-	file->private_data = __aa_get_loaddata(inode->i_private);
-	if (!file->private_data)
+
+	loaddata = __aa_get_loaddata(inode->i_private);
+	if (!loaddata)
 		/* lost race: this entry is being reaped */
 		return -ENOENT;
 
+	private = rawdata_f_data_alloc(loaddata->size);
+	if (IS_ERR(private)) {
+		error = PTR_ERR(private);
+		goto fail_private_alloc;
+	}
+
+	private->loaddata = loaddata;
+
+	error = deflate_decompress(loaddata->data, loaddata->compressed_size,
+				   RAWDATA_F_DATA_BUF(private),
+				   loaddata->size);
+	if (error)
+		goto fail_decompress;
+
+	file->private_data = private;
 	return 0;
+
+fail_decompress:
+	rawdata_f_data_free(private);
+	return error;
+
+fail_private_alloc:
+	aa_put_loaddata(loaddata);
+	return error;
 }
 
 static const struct file_operations rawdata_fops = {
@@ -1388,6 +1499,13 @@ int __aa_fs_create_rawdata(struct aa_ns *ns, struct aa_loaddata *rawdata)
 		rawdata->dents[AAFS_LOADDATA_HASH] = dent;
 	}
 
+	dent = aafs_create_file("compressed_size", S_IFREG | 0444, dir,
+				rawdata,
+				&seq_rawdata_compressed_size_fops);
+	if (IS_ERR(dent))
+		goto fail;
+	rawdata->dents[AAFS_LOADDATA_COMPRESSED_SIZE] = dent;
+
 	dent = aafs_create_file("raw_data", S_IFREG | 0444,
 				      dir, rawdata, &rawdata_fops);
 	if (IS_ERR(dent))

security/apparmor/domain.c

@@ -520,7 +520,7 @@ struct aa_label *x_table_lookup(struct aa_profile *profile, u32 xindex,
 				label = &new_profile->label;
 			continue;
 		}
-		label = aa_label_parse(&profile->label, *name, GFP_ATOMIC,
+		label = aa_label_parse(&profile->label, *name, GFP_KERNEL,
 				       true, false);
 		if (IS_ERR(label))
 			label = NULL;
@@ -600,7 +600,7 @@ static struct aa_label *x_to_label(struct aa_profile *profile,
 		/* base the stack on post domain transition */
 		struct aa_label *base = new;
 
-		new = aa_label_parse(base, stack, GFP_ATOMIC, true, false);
+		new = aa_label_parse(base, stack, GFP_KERNEL, true, false);
 		if (IS_ERR(new))
 			new = NULL;
 		aa_put_label(base);
@@ -685,20 +685,9 @@ static struct aa_label *profile_transition(struct aa_profile *profile,
 	} else if (COMPLAIN_MODE(profile)) {
 		/* no exec permission - learning mode */
 		struct aa_profile *new_profile = NULL;
-		char *n = kstrdup(name, GFP_ATOMIC);
-
-		if (n) {
-			/* name is ptr into buffer */
-			long pos = name - buffer;
-			/* break per cpu buffer hold */
-			put_buffers(buffer);
-			new_profile = aa_new_null_profile(profile, false, n,
+
+		new_profile = aa_new_null_profile(profile, false, name,
 						  GFP_KERNEL);
-			get_buffers(buffer);
-			name = buffer + pos;
-			strcpy((char *)name, n);
-			kfree(n);
-		}
 		if (!new_profile) {
 			error = -ENOMEM;
 			info = "could not create null profile";
@@ -719,7 +708,7 @@ static struct aa_label *profile_transition(struct aa_profile *profile,
 		if (DEBUG_ON) {
 			dbg_printk("apparmor: scrubbing environment variables"
 				   " for %s profile=", name);
-			aa_label_printk(new, GFP_ATOMIC);
+			aa_label_printk(new, GFP_KERNEL);
 			dbg_printk("\n");
 		}
 		*secure_exec = true;
@@ -795,7 +784,7 @@ static int profile_onexec(struct aa_profile *profile, struct aa_label *onexec,
 		if (DEBUG_ON) {
 			dbg_printk("apparmor: scrubbing environment "
 				   "variables for %s label=", xname);
-			aa_label_printk(onexec, GFP_ATOMIC);
+			aa_label_printk(onexec, GFP_KERNEL);
 			dbg_printk("\n");
 		}
 		*secure_exec = true;
@@ -829,7 +818,7 @@ static struct aa_label *handle_onexec(struct aa_label *label,
 					       bprm, buffer, cond, unsafe));
 		if (error)
 			return ERR_PTR(error);
-		new = fn_label_build_in_ns(label, profile, GFP_ATOMIC,
+		new = fn_label_build_in_ns(label, profile, GFP_KERNEL,
 				aa_get_newest_label(onexec),
 				profile_transition(profile, bprm, buffer,
 						   cond, unsafe));
@@ -841,9 +830,9 @@ static struct aa_label *handle_onexec(struct aa_label *label,
 					       buffer, cond, unsafe));
 		if (error)
 			return ERR_PTR(error);
-		new = fn_label_build_in_ns(label, profile, GFP_ATOMIC,
+		new = fn_label_build_in_ns(label, profile, GFP_KERNEL,
 				aa_label_merge(&profile->label, onexec,
-					       GFP_ATOMIC),
+					       GFP_KERNEL),
 				profile_transition(profile, bprm, buffer,
 						   cond, unsafe));
 	}
@@ -903,13 +892,18 @@ int apparmor_bprm_set_creds(struct linux_binprm *bprm)
 		ctx->nnp = aa_get_label(label);
 
 	/* buffer freed below, name is pointer into buffer */
-	get_buffers(buffer);
+	buffer = aa_get_buffer(false);
+	if (!buffer) {
+		error = -ENOMEM;
+		goto done;
+	}
+
 	/* Test for onexec first as onexec override other x transitions. */
 	if (ctx->onexec)
 		new = handle_onexec(label, ctx->onexec, ctx->token,
 				    bprm, buffer, &cond, &unsafe);
 	else
-		new = fn_label_build(label, profile, GFP_ATOMIC,
+		new = fn_label_build(label, profile, GFP_KERNEL,
 				profile_transition(profile, bprm, buffer,
 						   &cond, &unsafe));
 
@@ -953,7 +947,7 @@ int apparmor_bprm_set_creds(struct linux_binprm *bprm)
 		if (DEBUG_ON) {
 			dbg_printk("scrubbing environment variables for %s "
 				   "label=", bprm->filename);
-			aa_label_printk(new, GFP_ATOMIC);
+			aa_label_printk(new, GFP_KERNEL);
 			dbg_printk("\n");
 		}
 		bprm->secureexec = 1;
@@ -964,7 +958,7 @@ int apparmor_bprm_set_creds(struct linux_binprm *bprm)
 		if (DEBUG_ON) {
 			dbg_printk("apparmor: clearing unsafe personality "
 				   "bits. %s label=", bprm->filename);
-			aa_label_printk(new, GFP_ATOMIC);
+			aa_label_printk(new, GFP_KERNEL);
 			dbg_printk("\n");
 		}
 		bprm->per_clear |= PER_CLEAR_ON_SETID;
@@ -975,7 +969,7 @@ int apparmor_bprm_set_creds(struct linux_binprm *bprm)
 
 done:
 	aa_put_label(label);
-	put_buffers(buffer);
+	aa_put_buffer(buffer);
 
 	return error;
 

security/apparmor/file.c

@@ -76,7 +76,7 @@ static void file_audit_cb(struct audit_buffer *ab, void *va)
 	if (aad(sa)->peer) {
 		audit_log_format(ab, " target=");
 		aa_label_xaudit(ab, labels_ns(aad(sa)->label), aad(sa)->peer,
-				FLAG_VIEW_SUBNS, GFP_ATOMIC);
+				FLAG_VIEW_SUBNS, GFP_KERNEL);
 	} else if (aad(sa)->fs.target) {
 		audit_log_format(ab, " target=");
 		audit_log_untrustedstring(ab, aad(sa)->fs.target);
@@ -332,12 +332,14 @@ int aa_path_perm(const char *op, struct aa_label *label,
 
 	flags |= PATH_DELEGATE_DELETED | (S_ISDIR(cond->mode) ? PATH_IS_DIR :
 								0);
-	get_buffers(buffer);
+	buffer = aa_get_buffer(false);
+	if (!buffer)
+		return -ENOMEM;
 	error = fn_for_each_confined(label, profile,
 			profile_path_perm(op, profile, path, buffer, request,
 					  cond, flags, &perms));
 
-	put_buffers(buffer);
+	aa_put_buffer(buffer);
 
 	return error;
 }
@@ -475,12 +477,18 @@ int aa_path_link(struct aa_label *label, struct dentry *old_dentry,
 	int error;
 
 	/* buffer freed below, lname is pointer in buffer */
-	get_buffers(buffer, buffer2);
+	buffer = aa_get_buffer(false);
+	buffer2 = aa_get_buffer(false);
+	error = -ENOMEM;
+	if (!buffer || !buffer2)
+		goto out;
+
 	error = fn_for_each_confined(label, profile,
 			profile_path_link(profile, &link, buffer, &target,
 					  buffer2, &cond));
-	put_buffers(buffer, buffer2);
-
+out:
+	aa_put_buffer(buffer);
+	aa_put_buffer(buffer2);
 	return error;
 }
 
@@ -507,7 +515,7 @@ static void update_file_ctx(struct aa_file_ctx *fctx, struct aa_label *label,
 
 static int __file_path_perm(const char *op, struct aa_label *label,
 			    struct aa_label *flabel, struct file *file,
-			    u32 request, u32 denied)
+			    u32 request, u32 denied, bool in_atomic)
 {
 	struct aa_profile *profile;
 	struct aa_perms perms = {};
@@ -524,7 +532,9 @@ static int __file_path_perm(const char *op, struct aa_label *label,
 		return 0;
 
 	flags = PATH_DELEGATE_DELETED | (S_ISDIR(cond.mode) ? PATH_IS_DIR : 0);
-	get_buffers(buffer);
+	buffer = aa_get_buffer(in_atomic);
+	if (!buffer)
+		return -ENOMEM;
 
 	/* check every profile in task label not in current cache */
 	error = fn_for_each_not_in_set(flabel, label, profile,
@@ -553,7 +563,7 @@ static int __file_path_perm(const char *op, struct aa_label *label,
 	if (!error)
 		update_file_ctx(file_ctx(file), label, request);
 
-	put_buffers(buffer);
+	aa_put_buffer(buffer);
 
 	return error;
 }
@@ -590,11 +600,12 @@ static int __file_sock_perm(const char *op, struct aa_label *label,
  * @label: label being enforced   (NOT NULL)
  * @file: file to revalidate access permissions on  (NOT NULL)
  * @request: requested permissions
+ * @in_atomic: whether allocations need to be done in atomic context
  *
  * Returns: %0 if access allowed else error
  */
 int aa_file_perm(const char *op, struct aa_label *label, struct file *file,
-		 u32 request)
+		 u32 request, bool in_atomic)
 {
 	struct aa_file_ctx *fctx;
 	struct aa_label *flabel;
@@ -607,7 +618,8 @@ int aa_file_perm(const char *op, struct aa_label *label, struct file *file,
 	fctx = file_ctx(file);
 
 	rcu_read_lock();
-	flabel  = rcu_dereference(fctx->label);
+	flabel  = aa_get_newest_label(rcu_dereference(fctx->label));
+	rcu_read_unlock();
 	AA_BUG(!flabel);
 
 	/* revalidate access, if task is unconfined, or the cached cred
@@ -626,14 +638,13 @@ int aa_file_perm(const char *op, struct aa_label *label, struct file *file,
 
 	if (file->f_path.mnt && path_mediated_fs(file->f_path.dentry))
 		error = __file_path_perm(op, label, flabel, file, request,
-					 denied);
+					 denied, in_atomic);
 
 	else if (S_ISSOCK(file_inode(file)->i_mode))
 		error = __file_sock_perm(op, label, flabel, file, request,
 					 denied);
 done:
-	rcu_read_unlock();
-
+	aa_put_label(flabel);
 	return error;
 }
 
@@ -655,7 +666,8 @@ static void revalidate_tty(struct aa_label *label)
 					     struct tty_file_private, list);
 		file = file_priv->file;
 
-		if (aa_file_perm(OP_INHERIT, label, file, MAY_READ | MAY_WRITE))
+		if (aa_file_perm(OP_INHERIT, label, file, MAY_READ | MAY_WRITE,
+				 IN_ATOMIC))
 			drop_tty = 1;
 	}
 	spin_unlock(&tty->files_lock);
@@ -669,7 +681,8 @@ static int match_file(const void *p, struct file *file, unsigned int fd)
 {
 	struct aa_label *label = (struct aa_label *)p;
 
-	if (aa_file_perm(OP_INHERIT, label, file, aa_map_file_to_perms(file)))
+	if (aa_file_perm(OP_INHERIT, label, file, aa_map_file_to_perms(file),
+			 IN_ATOMIC))
 		return fd + 1;
 	return 0;
 }

security/apparmor/include/apparmor.h

@@ -36,6 +36,7 @@ extern enum audit_mode aa_g_audit;
 extern bool aa_g_audit_header;
 extern bool aa_g_debug;
 extern bool aa_g_hash_policy;
+extern int aa_g_rawdata_compression_level;
 extern bool aa_g_lock_policy;
 extern bool aa_g_logsyscall;
 extern bool aa_g_paranoid_load;

security/apparmor/include/file.h

@@ -197,7 +197,7 @@ int aa_path_link(struct aa_label *label, struct dentry *old_dentry,
 		 const struct path *new_dir, struct dentry *new_dentry);
 
 int aa_file_perm(const char *op, struct aa_label *label, struct file *file,
-		 u32 request);
+		 u32 request, bool in_atomic);
 
 void aa_inherit_files(const struct cred *cred, struct files_struct *files);
 

security/apparmor/include/match.h

@@ -134,7 +134,7 @@ unsigned int aa_dfa_matchn_until(struct aa_dfa *dfa, unsigned int start,
 
 void aa_dfa_free_kref(struct kref *kref);
 
-#define WB_HISTORY_SIZE 8
+#define WB_HISTORY_SIZE 24
 struct match_workbuf {
 	unsigned int count;
 	unsigned int pos;
@@ -147,7 +147,6 @@ struct match_workbuf N = {		\
 	.count = 0,			\
 	.pos = 0,			\
 	.len = 0,			\
-	.size = WB_HISTORY_SIZE,			\
 }
 
 unsigned int aa_dfa_leftmatch(struct aa_dfa *dfa, unsigned int start,

security/apparmor/include/path.h

@@ -11,7 +11,6 @@
 #ifndef __AA_PATH_H
 #define __AA_PATH_H
 
-
 enum path_flags {
 	PATH_IS_DIR = 0x1,		/* path is a directory */
 	PATH_CONNECT_PATH = 0x4,	/* connect disconnected paths to / */
@@ -26,51 +25,8 @@ int aa_path_name(const struct path *path, int flags, char *buffer,
 		 const char **name, const char **info,
 		 const char *disconnected);
 
-#define MAX_PATH_BUFFERS 2
-
-/* Per cpu buffers used during mediation */
-/* preallocated buffers to use during path lookups */
-struct aa_buffers {
-	char *buf[MAX_PATH_BUFFERS];
-};
-
-#include <linux/percpu.h>
-#include <linux/preempt.h>
-
-DECLARE_PER_CPU(struct aa_buffers, aa_buffers);
-
-#define ASSIGN(FN, A, X, N) ((X) = FN(A, N))
-#define EVAL1(FN, A, X) ASSIGN(FN, A, X, 0) /*X = FN(0)*/
-#define EVAL2(FN, A, X, Y...)	\
-	do { ASSIGN(FN, A, X, 1);  EVAL1(FN, A, Y); } while (0)
-#define EVAL(FN, A, X...) CONCATENATE(EVAL, COUNT_ARGS(X))(FN, A, X)
-
-#define for_each_cpu_buffer(I) for ((I) = 0; (I) < MAX_PATH_BUFFERS; (I)++)
-
-#ifdef CONFIG_DEBUG_PREEMPT
-#define AA_BUG_PREEMPT_ENABLED(X) AA_BUG(preempt_count() <= 0, X)
-#else
-#define AA_BUG_PREEMPT_ENABLED(X) /* nop */
-#endif
-
-#define __get_buffer(C, N) ({						\
-	AA_BUG_PREEMPT_ENABLED("__get_buffer without preempt disabled");  \
-	(C)->buf[(N)]; })
-
-#define __get_buffers(C, X...)    EVAL(__get_buffer, C, X)
-
-#define __put_buffers(X, Y...) ((void)&(X))
-
-#define get_buffers(X...)						\
-do {									\
-	struct aa_buffers *__cpu_var = get_cpu_ptr(&aa_buffers);	\
-	__get_buffers(__cpu_var, X);					\
-} while (0)
-
-#define put_buffers(X, Y...)		\
-do {					\
-	__put_buffers(X, Y);		\
-	put_cpu_ptr(&aa_buffers);	\
-} while (0)
+#define IN_ATOMIC true
+char *aa_get_buffer(bool in_atomic);
+void aa_put_buffer(char *buf);
 
 #endif /* __AA_PATH_H */

security/apparmor/include/policy_unpack.h

@@ -41,6 +41,7 @@ enum {
 	AAFS_LOADDATA_REVISION,
 	AAFS_LOADDATA_HASH,
 	AAFS_LOADDATA_DATA,
+	AAFS_LOADDATA_COMPRESSED_SIZE,
 	AAFS_LOADDATA_DIR,		/* must be last actual entry */
 	AAFS_LOADDATA_NDENTS		/* count of entries */
 };
@@ -61,11 +62,16 @@ struct aa_loaddata {
 	struct dentry *dents[AAFS_LOADDATA_NDENTS];
 	struct aa_ns *ns;
 	char *name;
-	size_t size;
+	size_t size;			/* the original size of the payload */
+	size_t compressed_size;		/* the compressed size of the payload */
 	long revision;			/* the ns policy revision this caused */
 	int abi;
 	unsigned char *hash;
 
+	/* Pointer to payload. If @compressed_size > 0, then this is the
+	 * compressed version of the payload, else it is the uncompressed
+	 * version (with the size indicated by @size).
+	 */
 	char *data;
 };
 

security/apparmor/label.c

@@ -1458,11 +1458,13 @@ static inline bool use_label_hname(struct aa_ns *ns, struct aa_label *label,
 /* helper macro for snprint routines */
 #define update_for_len(total, len, size, str)	\
 do {					\
+	size_t ulen = len;		\
+					\
 	AA_BUG(len < 0);		\
-	total += len;			\
-	len = min(len, size);		\
-	size -= len;			\
-	str += len;			\
+	total += ulen;			\
+	ulen = min(ulen, size);		\
+	size -= ulen;			\
+	str += ulen;			\
 } while (0)
 
 /**
@@ -1597,7 +1599,7 @@ int aa_label_snxprint(char *str, size_t size, struct aa_ns *ns,
 	struct aa_ns *prev_ns = NULL;
 	struct label_it i;
 	int count = 0, total = 0;
-	size_t len;
+	ssize_t len;
 
 	AA_BUG(!str && size != 0);
 	AA_BUG(!label);

security/apparmor/lsm.c

@@ -21,6 +21,7 @@
 #include <linux/user_namespace.h>
 #include <linux/netfilter_ipv4.h>
 #include <linux/netfilter_ipv6.h>
+#include <linux/zlib.h>
 #include <net/sock.h>
 #include <uapi/linux/mount.h>
 
@@ -43,8 +44,17 @@
 /* Flag indicating whether initialization completed */
 int apparmor_initialized;
 
-DEFINE_PER_CPU(struct aa_buffers, aa_buffers);
+union aa_buffer {
+	struct list_head list;
+	char buffer[1];
+};
+
+#define RESERVE_COUNT 2
+static int reserve_count = RESERVE_COUNT;
+static int buffer_count;
 
+static LIST_HEAD(aa_global_buffers);
+static DEFINE_SPINLOCK(aa_buffers_lock);
 
 /*
  * LSM hook functions
@@ -442,7 +452,8 @@ static void apparmor_file_free_security(struct file *file)
 		aa_put_label(rcu_access_pointer(ctx->label));
 }
 
-static int common_file_perm(const char *op, struct file *file, u32 mask)
+static int common_file_perm(const char *op, struct file *file, u32 mask,
+			    bool in_atomic)
 {
 	struct aa_label *label;
 	int error = 0;
@@ -452,7 +463,7 @@ static int common_file_perm(const char *op, struct file *file, u32 mask)
 		return -EACCES;
 
 	label = __begin_current_label_crit_section();
-	error = aa_file_perm(op, label, file, mask);
+	error = aa_file_perm(op, label, file, mask, in_atomic);
 	__end_current_label_crit_section(label);
 
 	return error;
@@ -460,12 +471,13 @@ static int common_file_perm(const char *op, struct file *file, u32 mask)
 
 static int apparmor_file_receive(struct file *file)
 {
-	return common_file_perm(OP_FRECEIVE, file, aa_map_file_to_perms(file));
+	return common_file_perm(OP_FRECEIVE, file, aa_map_file_to_perms(file),
+				false);
 }
 
 static int apparmor_file_permission(struct file *file, int mask)
 {
-	return common_file_perm(OP_FPERM, file, mask);
+	return common_file_perm(OP_FPERM, file, mask, false);
 }
 
 static int apparmor_file_lock(struct file *file, unsigned int cmd)
@@ -475,11 +487,11 @@ static int apparmor_file_lock(struct file *file, unsigned int cmd)
 	if (cmd == F_WRLCK)
 		mask |= MAY_WRITE;
 
-	return common_file_perm(OP_FLOCK, file, mask);
+	return common_file_perm(OP_FLOCK, file, mask, false);
 }
 
 static int common_mmap(const char *op, struct file *file, unsigned long prot,
-		       unsigned long flags)
+		       unsigned long flags, bool in_atomic)
 {
 	int mask = 0;
 
@@ -497,20 +509,21 @@ static int common_mmap(const char *op, struct file *file, unsigned long prot,
 	if (prot & PROT_EXEC)
 		mask |= AA_EXEC_MMAP;
 
-	return common_file_perm(op, file, mask);
+	return common_file_perm(op, file, mask, in_atomic);
 }
 
 static int apparmor_mmap_file(struct file *file, unsigned long reqprot,
 			      unsigned long prot, unsigned long flags)
 {
-	return common_mmap(OP_FMMAP, file, prot, flags);
+	return common_mmap(OP_FMMAP, file, prot, flags, GFP_ATOMIC);
 }
 
 static int apparmor_file_mprotect(struct vm_area_struct *vma,
 				  unsigned long reqprot, unsigned long prot)
 {
 	return common_mmap(OP_FMPROT, vma->vm_file, prot,
-			   !(vma->vm_flags & VM_SHARED) ? MAP_PRIVATE : 0);
+			   !(vma->vm_flags & VM_SHARED) ? MAP_PRIVATE : 0,
+			   false);
 }
 
 static int apparmor_sb_mount(const char *dev_name, const struct path *path,
@@ -1262,6 +1275,16 @@ static const struct kernel_param_ops param_ops_aauint = {
 	.get = param_get_aauint
 };
 
+static int param_set_aacompressionlevel(const char *val,
+					const struct kernel_param *kp);
+static int param_get_aacompressionlevel(char *buffer,
+					const struct kernel_param *kp);
+#define param_check_aacompressionlevel param_check_int
+static const struct kernel_param_ops param_ops_aacompressionlevel = {
+	.set = param_set_aacompressionlevel,
+	.get = param_get_aacompressionlevel
+};
+
 static int param_set_aalockpolicy(const char *val, const struct kernel_param *kp);
 static int param_get_aalockpolicy(char *buffer, const struct kernel_param *kp);
 #define param_check_aalockpolicy param_check_bool
@@ -1292,6 +1315,11 @@ bool aa_g_hash_policy = IS_ENABLED(CONFIG_SECURITY_APPARMOR_HASH_DEFAULT);
 module_param_named(hash_policy, aa_g_hash_policy, aabool, S_IRUSR | S_IWUSR);
 #endif
 
+/* policy loaddata compression level */
+int aa_g_rawdata_compression_level = Z_DEFAULT_COMPRESSION;
+module_param_named(rawdata_compression_level, aa_g_rawdata_compression_level,
+		   aacompressionlevel, 0400);
+
 /* Debug mode */
 bool aa_g_debug = IS_ENABLED(CONFIG_SECURITY_APPARMOR_DEBUG_MESSAGES);
 module_param_named(debug, aa_g_debug, aabool, S_IRUSR | S_IWUSR);
@@ -1402,6 +1430,7 @@ static int param_set_aauint(const char *val, const struct kernel_param *kp)
 		return -EPERM;
 
 	error = param_set_uint(val, kp);
+	aa_g_path_max = max_t(uint32_t, aa_g_path_max, sizeof(union aa_buffer));
 	pr_info("AppArmor: buffer size set to %d bytes\n", aa_g_path_max);
 
 	return error;
@@ -1456,6 +1485,37 @@ static int param_get_aaintbool(char *buffer, const struct kernel_param *kp)
 	return param_get_bool(buffer, &kp_local);
 }
 
+static int param_set_aacompressionlevel(const char *val,
+					const struct kernel_param *kp)
+{
+	int error;
+
+	if (!apparmor_enabled)
+		return -EINVAL;
+	if (apparmor_initialized)
+		return -EPERM;
+
+	error = param_set_int(val, kp);
+
+	aa_g_rawdata_compression_level = clamp(aa_g_rawdata_compression_level,
+					       Z_NO_COMPRESSION,
+					       Z_BEST_COMPRESSION);
+	pr_info("AppArmor: policy rawdata compression level set to %u\n",
+		aa_g_rawdata_compression_level);
+
+	return error;
+}
+
+static int param_get_aacompressionlevel(char *buffer,
+					const struct kernel_param *kp)
+{
+	if (!apparmor_enabled)
+		return -EINVAL;
+	if (apparmor_initialized && !policy_view_capable(NULL))
+		return -EPERM;
+	return param_get_int(buffer, kp);
+}
+
 static int param_get_audit(char *buffer, const struct kernel_param *kp)
 {
 	if (!apparmor_enabled)
@@ -1514,6 +1574,61 @@ static int param_set_mode(const char *val, const struct kernel_param *kp)
 	return 0;
 }
 
+char *aa_get_buffer(bool in_atomic)
+{
+	union aa_buffer *aa_buf;
+	bool try_again = true;
+	gfp_t flags = (GFP_KERNEL | __GFP_RETRY_MAYFAIL | __GFP_NOWARN);
+
+retry:
+	spin_lock(&aa_buffers_lock);
+	if (buffer_count > reserve_count ||
+	    (in_atomic && !list_empty(&aa_global_buffers))) {
+		aa_buf = list_first_entry(&aa_global_buffers, union aa_buffer,
+					  list);
+		list_del(&aa_buf->list);
+		buffer_count--;
+		spin_unlock(&aa_buffers_lock);
+		return &aa_buf->buffer[0];
+	}
+	if (in_atomic) {
+		/*
+		 * out of reserve buffers and in atomic context so increase
+		 * how many buffers to keep in reserve
+		 */
+		reserve_count++;
+		flags = GFP_ATOMIC;
+	}
+	spin_unlock(&aa_buffers_lock);
+
+	if (!in_atomic)
+		might_sleep();
+	aa_buf = kmalloc(aa_g_path_max, flags);
+	if (!aa_buf) {
+		if (try_again) {
+			try_again = false;
+			goto retry;
+		}
+		pr_warn_once("AppArmor: Failed to allocate a memory buffer.\n");
+		return NULL;
+	}
+	return &aa_buf->buffer[0];
+}
+
+void aa_put_buffer(char *buf)
+{
+	union aa_buffer *aa_buf;
+
+	if (!buf)
+		return;
+	aa_buf = container_of(buf, union aa_buffer, buffer[0]);
+
+	spin_lock(&aa_buffers_lock);
+	list_add(&aa_buf->list, &aa_global_buffers);
+	buffer_count++;
+	spin_unlock(&aa_buffers_lock);
+}
+
 /*
  * AppArmor init functions
  */
@@ -1525,7 +1640,7 @@ static int param_set_mode(const char *val, const struct kernel_param *kp)
  */
 static int __init set_init_ctx(void)
 {
-	struct cred *cred = (struct cred *)current->real_cred;
+	struct cred *cred = (__force struct cred *)current->real_cred;
 
 	set_cred_label(cred, aa_get_label(ns_unconfined(root_ns)));
 
@@ -1534,38 +1649,48 @@ static int __init set_init_ctx(void)
 
 static void destroy_buffers(void)
 {
-	u32 i, j;
+	union aa_buffer *aa_buf;
 
-	for_each_possible_cpu(i) {
-		for_each_cpu_buffer(j) {
-			kfree(per_cpu(aa_buffers, i).buf[j]);
-			per_cpu(aa_buffers, i).buf[j] = NULL;
-		}
+	spin_lock(&aa_buffers_lock);
+	while (!list_empty(&aa_global_buffers)) {
+		aa_buf = list_first_entry(&aa_global_buffers, union aa_buffer,
+					 list);
+		list_del(&aa_buf->list);
+		spin_unlock(&aa_buffers_lock);
+		kfree(aa_buf);
+		spin_lock(&aa_buffers_lock);
 	}
+	spin_unlock(&aa_buffers_lock);
 }
 
 static int __init alloc_buffers(void)
 {
-	u32 i, j;
-
-	for_each_possible_cpu(i) {
-		for_each_cpu_buffer(j) {
-			char *buffer;
+	union aa_buffer *aa_buf;
+	int i, num;
 
-			if (cpu_to_node(i) > num_online_nodes())
-				/* fallback to kmalloc for offline nodes */
-				buffer = kmalloc(aa_g_path_max, GFP_KERNEL);
+	/*
+	 * A function may require two buffers at once. Usually the buffers are
+	 * used for a short period of time and are shared. On UP kernel buffers
+	 * two should be enough, with more CPUs it is possible that more
+	 * buffers will be used simultaneously. The preallocated pool may grow.
+	 * This preallocation has also the side-effect that AppArmor will be
+	 * disabled early at boot if aa_g_path_max is extremly high.
+	 */
+	if (num_online_cpus() > 1)
+		num = 4 + RESERVE_COUNT;
 	else
-				buffer = kmalloc_node(aa_g_path_max, GFP_KERNEL,
-						      cpu_to_node(i));
-			if (!buffer) {
+		num = 2 + RESERVE_COUNT;
+
+	for (i = 0; i < num; i++) {
+
+		aa_buf = kmalloc(aa_g_path_max, GFP_KERNEL |
+				 __GFP_RETRY_MAYFAIL | __GFP_NOWARN);
+		if (!aa_buf) {
 			destroy_buffers();
 			return -ENOMEM;
 		}
-			per_cpu(aa_buffers, i).buf[j] = buffer;
-		}
+		aa_put_buffer(&aa_buf->buffer[0]);
 	}
-
 	return 0;
 }
 
@@ -1730,7 +1855,7 @@ static int __init apparmor_init(void)
 	error = alloc_buffers();
 	if (error) {
 		AA_ERROR("Unable to allocate work buffers\n");
-		goto buffers_out;
+		goto alloc_out;
 	}
 
 	error = set_init_ctx();
@@ -1755,7 +1880,6 @@ static int __init apparmor_init(void)
 
 buffers_out:
 	destroy_buffers();
-
 alloc_out:
 	aa_destroy_aafs();
 	aa_teardown_dfa_engine();

security/apparmor/match.c

@@ -616,8 +616,8 @@ unsigned int aa_dfa_matchn_until(struct aa_dfa *dfa, unsigned int start,
 
 #define inc_wb_pos(wb)						\
 do {								\
-	wb->pos = (wb->pos + 1) & (wb->size - 1);		\
-	wb->len = (wb->len + 1) & (wb->size - 1);		\
+	wb->pos = (wb->pos + 1) & (WB_HISTORY_SIZE - 1);		\
+	wb->len = (wb->len + 1) & (WB_HISTORY_SIZE - 1);		\
 } while (0)
 
 /* For DFAs that don't support extended tagging of states */
@@ -636,7 +636,7 @@ static bool is_loop(struct match_workbuf *wb, unsigned int state,
 			return true;
 		}
 		if (pos == 0)
-			pos = wb->size;
+			pos = WB_HISTORY_SIZE;
 		pos--;
 	}
 

security/apparmor/mount.c

@@ -408,11 +408,13 @@ int aa_remount(struct aa_label *label, const struct path *path,
 
 	binary = path->dentry->d_sb->s_type->fs_flags & FS_BINARY_MOUNTDATA;
 
-	get_buffers(buffer);
+	buffer = aa_get_buffer(false);
+	if (!buffer)
+		return -ENOMEM;
 	error = fn_for_each_confined(label, profile,
 			match_mnt(profile, path, buffer, NULL, NULL, NULL,
 				  flags, data, binary));
-	put_buffers(buffer);
+	aa_put_buffer(buffer);
 
 	return error;
 }
@@ -437,11 +439,18 @@ int aa_bind_mount(struct aa_label *label, const struct path *path,
 	if (error)
 		return error;
 
-	get_buffers(buffer, old_buffer);
+	buffer = aa_get_buffer(false);
+	old_buffer = aa_get_buffer(false);
+	error = -ENOMEM;
+	if (!buffer || old_buffer)
+		goto out;
+
 	error = fn_for_each_confined(label, profile,
 			match_mnt(profile, path, buffer, &old_path, old_buffer,
 				  NULL, flags, NULL, false));
-	put_buffers(buffer, old_buffer);
+out:
+	aa_put_buffer(buffer);
+	aa_put_buffer(old_buffer);
 	path_put(&old_path);
 
 	return error;
@@ -461,11 +470,13 @@ int aa_mount_change_type(struct aa_label *label, const struct path *path,
 	flags &= (MS_REC | MS_SILENT | MS_SHARED | MS_PRIVATE | MS_SLAVE |
 		  MS_UNBINDABLE);
 
-	get_buffers(buffer);
+	buffer = aa_get_buffer(false);
+	if (!buffer)
+		return -ENOMEM;
 	error = fn_for_each_confined(label, profile,
 			match_mnt(profile, path, buffer, NULL, NULL, NULL,
 				  flags, NULL, false));
-	put_buffers(buffer);
+	aa_put_buffer(buffer);
 
 	return error;
 }
@@ -488,11 +499,17 @@ int aa_move_mount(struct aa_label *label, const struct path *path,
 	if (error)
 		return error;
 
-	get_buffers(buffer, old_buffer);
+	buffer = aa_get_buffer(false);
+	old_buffer = aa_get_buffer(false);
+	error = -ENOMEM;
+	if (!buffer || !old_buffer)
+		goto out;
 	error = fn_for_each_confined(label, profile,
 			match_mnt(profile, path, buffer, &old_path, old_buffer,
 				  NULL, MS_MOVE, NULL, false));
-	put_buffers(buffer, old_buffer);
+out:
+	aa_put_buffer(buffer);
+	aa_put_buffer(old_buffer);
 	path_put(&old_path);
 
 	return error;
@@ -533,8 +550,17 @@ int aa_new_mount(struct aa_label *label, const char *dev_name,
 		}
 	}
 
-	get_buffers(buffer, dev_buffer);
+	buffer = aa_get_buffer(false);
+	if (!buffer) {
+		error = -ENOMEM;
+		goto out;
+	}
 	if (dev_path) {
+		dev_buffer = aa_get_buffer(false);
+		if (!dev_buffer) {
+			error = -ENOMEM;
+			goto out;
+		}
 		error = fn_for_each_confined(label, profile,
 			match_mnt(profile, path, buffer, dev_path, dev_buffer,
 				  type, flags, data, binary));
@@ -543,7 +569,10 @@ int aa_new_mount(struct aa_label *label, const char *dev_name,
 			match_mnt_path_str(profile, path, buffer, dev_name,
 					   type, flags, data, binary, NULL));
 	}
-	put_buffers(buffer, dev_buffer);
+
+out:
+	aa_put_buffer(buffer);
+	aa_put_buffer(dev_buffer);
 	if (dev_path)
 		path_put(dev_path);
 
@@ -591,10 +620,13 @@ int aa_umount(struct aa_label *label, struct vfsmount *mnt, int flags)
 	AA_BUG(!label);
 	AA_BUG(!mnt);
 
-	get_buffers(buffer);
+	buffer = aa_get_buffer(false);
+	if (!buffer)
+		return -ENOMEM;
+
 	error = fn_for_each_confined(label, profile,
 			profile_umount(profile, &path, buffer));
-	put_buffers(buffer);
+	aa_put_buffer(buffer);
 
 	return error;
 }
@@ -667,8 +699,12 @@ int aa_pivotroot(struct aa_label *label, const struct path *old_path,
 	AA_BUG(!old_path);
 	AA_BUG(!new_path);
 
-	get_buffers(old_buffer, new_buffer);
-	target = fn_label_build(label, profile, GFP_ATOMIC,
+	old_buffer = aa_get_buffer(false);
+	new_buffer = aa_get_buffer(false);
+	error = -ENOMEM;
+	if (!old_buffer || !new_buffer)
+		goto out;
+	target = fn_label_build(label, profile, GFP_KERNEL,
 			build_pivotroot(profile, new_path, new_buffer,
 					old_path, old_buffer));
 	if (!target) {
@@ -686,7 +722,8 @@ int aa_pivotroot(struct aa_label *label, const struct path *old_path,
 		/* already audited error */
 		error = PTR_ERR(target);
 out:
-	put_buffers(old_buffer, new_buffer);
+	aa_put_buffer(old_buffer);
+	aa_put_buffer(new_buffer);
 
 	return error;
 

security/apparmor/policy.c

@@ -582,7 +582,7 @@ static int replacement_allowed(struct aa_profile *profile, int noreplace,
 {
 	if (profile) {
 		if (profile->label.flags & FLAG_IMMUTIBLE) {
-			*info = "cannot replace immutible profile";
+			*info = "cannot replace immutable profile";
 			return -EPERM;
 		} else if (noreplace) {
 			*info = "profile already exists";
@@ -856,7 +856,7 @@ static struct aa_profile *update_to_newest_parent(struct aa_profile *new)
 ssize_t aa_replace_profiles(struct aa_ns *policy_ns, struct aa_label *label,
 			    u32 mask, struct aa_loaddata *udata)
 {
-	const char *ns_name, *info = NULL;
+	const char *ns_name = NULL, *info = NULL;
 	struct aa_ns *ns = NULL;
 	struct aa_load_ent *ent, *tmp;
 	struct aa_loaddata *rawdata_ent;
@@ -1043,6 +1043,7 @@ ssize_t aa_replace_profiles(struct aa_ns *policy_ns, struct aa_label *label,
 out:
 	aa_put_ns(ns);
 	aa_put_loaddata(udata);
+	kfree(ns_name);
 
 	if (error)
 		return error;

security/apparmor/policy_unpack.c

@@ -16,6 +16,7 @@
 #include <asm/unaligned.h>
 #include <linux/ctype.h>
 #include <linux/errno.h>
+#include <linux/zlib.h>
 
 #include "include/apparmor.h"
 #include "include/audit.h"
@@ -139,9 +140,11 @@ bool aa_rawdata_eq(struct aa_loaddata *l, struct aa_loaddata *r)
 {
 	if (l->size != r->size)
 		return false;
+	if (l->compressed_size != r->compressed_size)
+		return false;
 	if (aa_g_hash_policy && memcmp(l->hash, r->hash, aa_hash_size()) != 0)
 		return false;
-	return memcmp(l->data, r->data, r->size) == 0;
+	return memcmp(l->data, r->data, r->compressed_size ?: r->size) == 0;
 }
 
 /*
@@ -968,11 +971,14 @@ static int verify_header(struct aa_ext *e, int required, const char **ns)
 				    e, error);
 			return error;
 		}
-		if (*ns && strcmp(*ns, name))
+		if (*ns && strcmp(*ns, name)) {
 			audit_iface(NULL, NULL, NULL, "invalid ns change", e,
 				    error);
-		else if (!*ns)
-			*ns = name;
+		} else if (!*ns) {
+			*ns = kstrdup(name, GFP_KERNEL);
+			if (!*ns)
+				return -ENOMEM;
+		}
 	}
 
 	return 0;
@@ -1039,6 +1045,105 @@ struct aa_load_ent *aa_load_ent_alloc(void)
 	return ent;
 }
 
+static int deflate_compress(const char *src, size_t slen, char **dst,
+			    size_t *dlen)
+{
+	int error;
+	struct z_stream_s strm;
+	void *stgbuf, *dstbuf;
+	size_t stglen = deflateBound(slen);
+
+	memset(&strm, 0, sizeof(strm));
+
+	if (stglen < slen)
+		return -EFBIG;
+
+	strm.workspace = kvzalloc(zlib_deflate_workspacesize(MAX_WBITS,
+							     MAX_MEM_LEVEL),
+				  GFP_KERNEL);
+	if (!strm.workspace)
+		return -ENOMEM;
+
+	error = zlib_deflateInit(&strm, aa_g_rawdata_compression_level);
+	if (error != Z_OK) {
+		error = -ENOMEM;
+		goto fail_deflate_init;
+	}
+
+	stgbuf = kvzalloc(stglen, GFP_KERNEL);
+	if (!stgbuf) {
+		error = -ENOMEM;
+		goto fail_stg_alloc;
+	}
+
+	strm.next_in = src;
+	strm.avail_in = slen;
+	strm.next_out = stgbuf;
+	strm.avail_out = stglen;
+
+	error = zlib_deflate(&strm, Z_FINISH);
+	if (error != Z_STREAM_END) {
+		error = -EINVAL;
+		goto fail_deflate;
+	}
+	error = 0;
+
+	if (is_vmalloc_addr(stgbuf)) {
+		dstbuf = kvzalloc(strm.total_out, GFP_KERNEL);
+		if (dstbuf) {
+			memcpy(dstbuf, stgbuf, strm.total_out);
+			kvfree(stgbuf);
+		}
+	} else
+		/*
+		 * If the staging buffer was kmalloc'd, then using krealloc is
+		 * probably going to be faster. The destination buffer will
+		 * always be smaller, so it's just shrunk, avoiding a memcpy
+		 */
+		dstbuf = krealloc(stgbuf, strm.total_out, GFP_KERNEL);
+
+	if (!dstbuf) {
+		error = -ENOMEM;
+		goto fail_deflate;
+	}
+
+	*dst = dstbuf;
+	*dlen = strm.total_out;
+
+fail_stg_alloc:
+	zlib_deflateEnd(&strm);
+fail_deflate_init:
+	kvfree(strm.workspace);
+	return error;
+
+fail_deflate:
+	kvfree(stgbuf);
+	goto fail_stg_alloc;
+}
+
+static int compress_loaddata(struct aa_loaddata *data)
+{
+
+	AA_BUG(data->compressed_size > 0);
+
+	/*
+	 * Shortcut the no compression case, else we increase the amount of
+	 * storage required by a small amount
+	 */
+	if (aa_g_rawdata_compression_level != 0) {
+		void *udata = data->data;
+		int error = deflate_compress(udata, data->size, &data->data,
+					     &data->compressed_size);
+		if (error)
+			return error;
+
+		kvfree(udata);
+	} else
+		data->compressed_size = data->size;
+
+	return 0;
+}
+
 /**
  * aa_unpack - unpack packed binary profile(s) data loaded from user space
  * @udata: user data copied to kmem  (NOT NULL)
@@ -1107,6 +1212,9 @@ int aa_unpack(struct aa_loaddata *udata, struct list_head *lh,
 			goto fail;
 		}
 	}
+	error = compress_loaddata(udata);
+	if (error)
+		goto fail;
 	return 0;
 
 fail_profile: