Re: Linux 3.18.73

[Greg KH <gregkh@linuxfoundation.org>]

diff --git a/Makefile b/Makefile
index 9b82f279ef1d..f5e683464cd4 100644
--- a/Makefile
+++ b/Makefile
@@ -1,6 +1,6 @@
 VERSION = 3
 PATCHLEVEL = 18
-SUBLEVEL = 72
+SUBLEVEL = 73
 EXTRAVERSION =
 NAME = Diseased Newt
 
diff --git a/arch/arm/xen/mm.c b/arch/arm/xen/mm.c
index f8a576b1d9bb..5409d70ffe6f 100644
--- a/arch/arm/xen/mm.c
+++ b/arch/arm/xen/mm.c
@@ -59,6 +59,7 @@ static struct dma_map_ops xen_swiotlb_dma_ops = {
 	.unmap_page = xen_swiotlb_unmap_page,
 	.dma_supported = xen_swiotlb_dma_supported,
 	.set_dma_mask = xen_swiotlb_set_dma_mask,
+	.mmap = xen_swiotlb_dma_mmap,
 };
 
 int __init xen_mm_init(void)
diff --git a/arch/arm64/kernel/head.S b/arch/arm64/kernel/head.S
index 2877dd818977..5c4b8d6e8ba0 100644
--- a/arch/arm64/kernel/head.S
+++ b/arch/arm64/kernel/head.S
@@ -264,6 +264,7 @@ ENDPROC(stext)
  * booted in EL1 or EL2 respectively.
  */
 ENTRY(el2_setup)
+	msr	SPsel, #1			// We want to use SP_EL{1,2}
 	mrs	x0, CurrentEL
 	cmp	x0, #CurrentEL_EL2
 	b.ne	1f
diff --git a/arch/powerpc/kvm/book3s_64_vio.c b/arch/powerpc/kvm/book3s_64_vio.c
index 54cf9bc94dad..3a095670b0c4 100644
--- a/arch/powerpc/kvm/book3s_64_vio.c
+++ b/arch/powerpc/kvm/book3s_64_vio.c
@@ -101,22 +101,17 @@ long kvm_vm_ioctl_create_spapr_tce(struct kvm *kvm,
 				   struct kvm_create_spapr_tce *args)
 {
 	struct kvmppc_spapr_tce_table *stt = NULL;
+	struct kvmppc_spapr_tce_table *siter;
 	long npages;
 	int ret = -ENOMEM;
 	int i;
 
-	/* Check this LIOBN hasn't been previously allocated */
-	list_for_each_entry(stt, &kvm->arch.spapr_tce_tables, list) {
-		if (stt->liobn == args->liobn)
-			return -EBUSY;
-	}
-
 	npages = kvmppc_stt_npages(args->window_size);
 
 	stt = kzalloc(sizeof(*stt) + npages * sizeof(struct page *),
 		      GFP_KERNEL);
 	if (!stt)
-		goto fail;
+		return ret;
 
 	stt->liobn = args->liobn;
 	stt->window_size = args->window_size;
@@ -128,23 +123,36 @@ long kvm_vm_ioctl_create_spapr_tce(struct kvm *kvm,
 			goto fail;
 	}
 
-	kvm_get_kvm(kvm);
-
 	mutex_lock(&kvm->lock);
-	list_add(&stt->list, &kvm->arch.spapr_tce_tables);
+
+	/* Check this LIOBN hasn't been previously allocated */
+	ret = 0;
+	list_for_each_entry(siter, &kvm->arch.spapr_tce_tables, list) {
+		if (siter->liobn == args->liobn) {
+			ret = -EBUSY;
+			break;
+		}
+	}
+
+	if (!ret)
+		ret = anon_inode_getfd("kvm-spapr-tce", &kvm_spapr_tce_fops,
+				       stt, O_RDWR | O_CLOEXEC);
+
+	if (ret >= 0) {
+		list_add(&stt->list, &kvm->arch.spapr_tce_tables);
+		kvm_get_kvm(kvm);
+	}
 
 	mutex_unlock(&kvm->lock);
 
-	return anon_inode_getfd("kvm-spapr-tce", &kvm_spapr_tce_fops,
-				stt, O_RDWR | O_CLOEXEC);
+	if (ret >= 0)
+		return ret;
 
-fail:
-	if (stt) {
-		for (i = 0; i < npages; i++)
-			if (stt->pages[i])
-				__free_page(stt->pages[i]);
+ fail:
+	for (i = 0; i < npages; i++)
+		if (stt->pages[i])
+			__free_page(stt->pages[i]);
 
-		kfree(stt);
-	}
+	kfree(stt);
 	return ret;
 }
diff --git a/arch/powerpc/platforms/pseries/mobility.c b/arch/powerpc/platforms/pseries/mobility.c
index f8c9ff7886e1..b86408e91e8b 100644
--- a/arch/powerpc/platforms/pseries/mobility.c
+++ b/arch/powerpc/platforms/pseries/mobility.c
@@ -225,8 +225,10 @@ static int add_dt_node(__be32 parent_phandle, __be32 drc_index)
 		return -ENOENT;
 
 	dn = dlpar_configure_connector(drc_index, parent_dn);
-	if (!dn)
+	if (!dn) {
+		of_node_put(parent_dn);
 		return -ENOENT;
+	}
 
 	rc = dlpar_attach_node(dn);
 	if (rc)
diff --git a/arch/x86/kernel/i387.c b/arch/x86/kernel/i387.c
index 8d6e954db2a7..9c9f4c0b0106 100644
--- a/arch/x86/kernel/i387.c
+++ b/arch/x86/kernel/i387.c
@@ -388,11 +388,22 @@ int xstateregs_set(struct task_struct *target, const struct user_regset *regset,
 	xsave_hdr = &target->thread.fpu.state->xsave.xsave_hdr;
 
 	xsave_hdr->xstate_bv &= pcntxt_mask;
+
+	/* xcomp_bv must be 0 when using uncompacted format */
+	if (!ret && xsave_hdr->xcomp_bv)
+		ret = -EINVAL;
+
 	/*
 	 * These bits must be zero.
 	 */
 	memset(xsave_hdr->reserved, 0, 48);
 
+	/*
+	 * In case of failure, mark all states as init:
+	 */
+	if (ret)
+		fpu_finit(&target->thread.fpu);
+
 	return ret;
 }
 
diff --git a/arch/x86/kernel/xsave.c b/arch/x86/kernel/xsave.c
index cdc6cf903078..460e72155f51 100644
--- a/arch/x86/kernel/xsave.c
+++ b/arch/x86/kernel/xsave.c
@@ -394,7 +394,9 @@ int __restore_xstate_sig(void __user *buf, void __user *buf_fx, int size)
 		drop_fpu(tsk);
 
 		if (__copy_from_user(&fpu->state->xsave, buf_fx, state_size) ||
-		    __copy_from_user(&env, buf, sizeof(env))) {
+		    __copy_from_user(&env, buf, sizeof(env)) ||
+		    (state_size > offsetof(struct xsave_struct, xsave_hdr) &&
+		     fpu->state->xsave.xsave_hdr.xcomp_bv)) {
 			fpu_finit(fpu);
 			err = -1;
 		} else {
diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index 99c004ddefd8..dd3ca375bfdf 100644
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -8275,6 +8275,11 @@ static void prepare_vmcs02(struct kvm_vcpu *vcpu, struct vmcs12 *vmcs12)
 		vmcs_write64(VIRTUAL_APIC_PAGE_ADDR,
 				page_to_phys(vmx->nested.virtual_apic_page));
 		vmcs_write32(TPR_THRESHOLD, vmcs12->tpr_threshold);
+	} else {
+#ifdef CONFIG_X86_64
+		exec_control |= CPU_BASED_CR8_LOAD_EXITING |
+				CPU_BASED_CR8_STORE_EXITING;
+#endif
 	}
 
 	/*
diff --git a/block/bsg-lib.c b/block/bsg-lib.c
index 650f427d915b..341b8d858e67 100644
--- a/block/bsg-lib.c
+++ b/block/bsg-lib.c
@@ -147,7 +147,6 @@ static int bsg_create_job(struct device *dev, struct request *req)
 failjob_rls_rqst_payload:
 	kfree(job->request_payload.sg_list);
 failjob_rls_job:
-	kfree(job);
 	return -ENOMEM;
 }
 
diff --git a/drivers/crypto/talitos.c b/drivers/crypto/talitos.c
index 00410b319b26..9fa17913941c 100644
--- a/drivers/crypto/talitos.c
+++ b/drivers/crypto/talitos.c
@@ -1581,9 +1581,9 @@ static int common_nonsnoop_hash(struct talitos_edesc *edesc,
 		req_ctx->swinit = 0;
 	} else {
 		desc->ptr[1] = zero_entry;
-		/* Indicate next op is not the first. */
-		req_ctx->first = 0;
 	}
+	/* Indicate next op is not the first. */
+	req_ctx->first = 0;
 
 	/* HMAC key */
 	if (ctx->keylen)
diff --git a/drivers/pci/pci-sysfs.c b/drivers/pci/pci-sysfs.c
index 66ba1ee09a6c..318707870cb2 100644
--- a/drivers/pci/pci-sysfs.c
+++ b/drivers/pci/pci-sysfs.c
@@ -513,7 +513,7 @@ static ssize_t driver_override_store(struct device *dev,
 				     const char *buf, size_t count)
 {
 	struct pci_dev *pdev = to_pci_dev(dev);
-	char *driver_override, *old = pdev->driver_override, *cp;
+	char *driver_override, *old, *cp;
 
 	/* We need to keep extra room for a newline */
 	if (count >= (PAGE_SIZE - 1))
@@ -527,12 +527,15 @@ static ssize_t driver_override_store(struct device *dev,
 	if (cp)
 		*cp = '\0';
 
+	device_lock(dev);
+	old = pdev->driver_override;
 	if (strlen(driver_override)) {
 		pdev->driver_override = driver_override;
 	} else {
 		kfree(driver_override);
 		pdev->driver_override = NULL;
 	}
+	device_unlock(dev);
 
 	kfree(old);
 
@@ -543,8 +546,12 @@ static ssize_t driver_override_show(struct device *dev,
 				    struct device_attribute *attr, char *buf)
 {
 	struct pci_dev *pdev = to_pci_dev(dev);
+	ssize_t len;
 
-	return snprintf(buf, PAGE_SIZE, "%s\n", pdev->driver_override);
+	device_lock(dev);
+	len = snprintf(buf, PAGE_SIZE, "%s\n", pdev->driver_override);
+	device_unlock(dev);
+	return len;
 }
 static DEVICE_ATTR_RW(driver_override);
 
diff --git a/drivers/scsi/scsi_transport_iscsi.c b/drivers/scsi/scsi_transport_iscsi.c
index 67d43e35693d..b5a653aed5a4 100644
--- a/drivers/scsi/scsi_transport_iscsi.c
+++ b/drivers/scsi/scsi_transport_iscsi.c
@@ -3693,7 +3693,7 @@ iscsi_if_rx(struct sk_buff *skb)
 		uint32_t group;
 
 		nlh = nlmsg_hdr(skb);
-		if (nlh->nlmsg_len < sizeof(*nlh) ||
+		if (nlh->nlmsg_len < sizeof(*nlh) + sizeof(*ev) ||
 		    skb->len < nlh->nlmsg_len) {
 			break;
 		}
diff --git a/drivers/video/fbdev/aty/atyfb_base.c b/drivers/video/fbdev/aty/atyfb_base.c
index 37ec09b3fffd..fd38ee820da6 100644
--- a/drivers/video/fbdev/aty/atyfb_base.c
+++ b/drivers/video/fbdev/aty/atyfb_base.c
@@ -1852,7 +1852,7 @@ static int atyfb_ioctl(struct fb_info *info, u_int cmd, u_long arg)
 #if defined(DEBUG) && defined(CONFIG_FB_ATY_CT)
 	case ATYIO_CLKR:
 		if (M64_HAS(INTEGRATED)) {
-			struct atyclk clk;
+			struct atyclk clk = { 0 };
 			union aty_pll *pll = &par->pll;
 			u32 dsp_config = pll->ct.dsp_config;
 			u32 dsp_on_off = pll->ct.dsp_on_off;
diff --git a/drivers/xen/swiotlb-xen.c b/drivers/xen/swiotlb-xen.c
index c9d0d5a0e662..c6d47e558488 100644
--- a/drivers/xen/swiotlb-xen.c
+++ b/drivers/xen/swiotlb-xen.c
@@ -684,3 +684,22 @@ xen_swiotlb_set_dma_mask(struct device *dev, u64 dma_mask)
 	return 0;
 }
 EXPORT_SYMBOL_GPL(xen_swiotlb_set_dma_mask);
+
+/*
+ * Create userspace mapping for the DMA-coherent memory.
+ * This function should be called with the pages from the current domain only,
+ * passing pages mapped from other domains would lead to memory corruption.
+ */
+int
+xen_swiotlb_dma_mmap(struct device *dev, struct vm_area_struct *vma,
+		     void *cpu_addr, dma_addr_t dma_addr, size_t size,
+		     struct dma_attrs *attrs)
+{
+#if defined(CONFIG_ARM) || defined(CONFIG_ARM64)
+	if (__generic_dma_ops(dev)->mmap)
+		return __generic_dma_ops(dev)->mmap(dev, vma, cpu_addr,
+						    dma_addr, size, attrs);
+#endif
+	return dma_common_mmap(dev, vma, cpu_addr, dma_addr, size);
+}
+EXPORT_SYMBOL_GPL(xen_swiotlb_dma_mmap);
diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c
index dd8526a659f8..a877e6279b10 100644
--- a/fs/btrfs/ioctl.c
+++ b/fs/btrfs/ioctl.c
@@ -3963,6 +3963,10 @@ static long btrfs_ioctl_default_subvol(struct file *file, void __user *argp)
 		ret = PTR_ERR(new_root);
 		goto out;
 	}
+	if (!is_fstree(new_root->objectid)) {
+		ret = -ENOENT;
+		goto out;
+	}
 
 	path = btrfs_alloc_path();
 	if (!path) {
diff --git a/fs/cifs/cifsfs.c b/fs/cifs/cifsfs.c
index 103e8b6604b1..b8158006e0ff 100644
--- a/fs/cifs/cifsfs.c
+++ b/fs/cifs/cifsfs.c
@@ -1311,7 +1311,7 @@ exit_cifs(void)
 	exit_cifs_idmap();
 #endif
 #ifdef CONFIG_CIFS_UPCALL
-	unregister_key_type(&cifs_spnego_key_type);
+	exit_cifs_spnego();
 #endif
 	cifs_destroy_request_bufs();
 	cifs_destroy_mids();
diff --git a/fs/cifs/connect.c b/fs/cifs/connect.c
index 32c46a5c489e..43df8c3e026c 100644
--- a/fs/cifs/connect.c
+++ b/fs/cifs/connect.c
@@ -3958,6 +3958,14 @@ cifs_setup_session(const unsigned int xid, struct cifs_ses *ses,
 	cifs_dbg(FYI, "Security Mode: 0x%x Capabilities: 0x%x TimeAdjust: %d\n",
 		 server->sec_mode, server->capabilities, server->timeAdj);
 
+	if (ses->auth_key.response) {
+		cifs_dbg(VFS, "Free previous auth_key.response = %p\n",
+			 ses->auth_key.response);
+		kfree(ses->auth_key.response);
+		ses->auth_key.response = NULL;
+		ses->auth_key.len = 0;
+	}
+
 	if (server->ops->sess_setup)
 		rc = server->ops->sess_setup(xid, ses, nls_info);
 
diff --git a/fs/cifs/file.c b/fs/cifs/file.c
index a3badede1b32..237c201d6d3e 100644
--- a/fs/cifs/file.c
+++ b/fs/cifs/file.c
@@ -225,6 +225,13 @@ cifs_nt_open(char *full_path, struct inode *inode, struct cifs_sb_info *cifs_sb,
 	if (backup_cred(cifs_sb))
 		create_options |= CREATE_OPEN_BACKUP_INTENT;
 
+	/* O_SYNC also has bit for O_DSYNC so following check picks up either */
+	if (f_flags & O_SYNC)
+		create_options |= CREATE_WRITE_THROUGH;
+
+	if (f_flags & O_DIRECT)
+		create_options |= CREATE_NO_BUFFER;
+
 	oparms.tcon = tcon;
 	oparms.cifs_sb = cifs_sb;
 	oparms.desired_access = desired_access;
diff --git a/fs/cifs/smb2pdu.c b/fs/cifs/smb2pdu.c
index 2c3047636d4e..fc5809d494ed 100644
--- a/fs/cifs/smb2pdu.c
+++ b/fs/cifs/smb2pdu.c
@@ -453,15 +453,22 @@ int smb3_validate_negotiate(const unsigned int xid, struct cifs_tcon *tcon)
 
 	/*
 	 * validation ioctl must be signed, so no point sending this if we
-	 * can not sign it.  We could eventually change this to selectively
+	 * can not sign it (ie are not known user).  Even if signing is not
+	 * required (enabled but not negotiated), in those cases we selectively
 	 * sign just this, the first and only signed request on a connection.
-	 * This is good enough for now since a user who wants better security
-	 * would also enable signing on the mount. Having validation of
-	 * negotiate info for signed connections helps reduce attack vectors
+	 * Having validation of negotiate info  helps reduce attack vectors.
 	 */
-	if (tcon->ses->server->sign == false)
+	if (tcon->ses->session_flags & SMB2_SESSION_FLAG_IS_GUEST)
 		return 0; /* validation requires signing */
 
+	if (tcon->ses->user_name == NULL) {
+		cifs_dbg(FYI, "Can't validate negotiate: null user mount\n");
+		return 0; /* validation requires signing */
+	}
+
+	if (tcon->ses->session_flags & SMB2_SESSION_FLAG_IS_NULL)
+		cifs_dbg(VFS, "Unexpected null user (anonymous) auth flag sent by server\n");
+
 	vneg_inbuf.Capabilities =
 			cpu_to_le32(tcon->ses->server->vals->req_capabilities);
 	memcpy(vneg_inbuf.Guid, tcon->ses->server->client_guid,
diff --git a/fs/read_write.c b/fs/read_write.c
index 7d9318c3d43c..1afb99c33c63 100644
--- a/fs/read_write.c
+++ b/fs/read_write.c
@@ -116,7 +116,7 @@ generic_file_llseek_size(struct file *file, loff_t offset, int whence,
 		 * In the generic case the entire file is data, so as long as
 		 * offset isn't at the end of the file then the offset is data.
 		 */
-		if (offset >= eof)
+		if ((unsigned long long)offset >= eof)
 			return -ENXIO;
 		break;
 	case SEEK_HOLE:
@@ -124,7 +124,7 @@ generic_file_llseek_size(struct file *file, loff_t offset, int whence,
 		 * There is a virtual hole at the end of the file, so as long as
 		 * offset isn't i_size or larger, return i_size.
 		 */
-		if (offset >= eof)
+		if ((unsigned long long)offset >= eof)
 			return -ENXIO;
 		offset = eof;
 		break;
diff --git a/include/linux/key.h b/include/linux/key.h
index e1d4715f3222..dcc00a7a5b8d 100644
--- a/include/linux/key.h
+++ b/include/linux/key.h
@@ -172,6 +172,7 @@ struct key {
 #define KEY_FLAG_TRUSTED_ONLY	9	/* set if keyring only accepts links to trusted keys */
 #define KEY_FLAG_BUILTIN	10	/* set if key is builtin */
 #define KEY_FLAG_ROOT_CAN_INVAL	11	/* set if key can be invalidated by root without permission */
+#define KEY_FLAG_UID_KEYRING	12	/* set if key is a user or user session keyring */
 
 	/* the key type and key description string
 	 * - the desc is used to match a key against search criteria
@@ -223,6 +224,7 @@ extern struct key *key_alloc(struct key_type *type,
 #define KEY_ALLOC_QUOTA_OVERRUN	0x0001	/* add to quota, permit even if overrun */
 #define KEY_ALLOC_NOT_IN_QUOTA	0x0002	/* not in quota */
 #define KEY_ALLOC_TRUSTED	0x0004	/* Key should be flagged as trusted */
+#define KEY_ALLOC_UID_KEYRING	0x0010	/* allocating a user or user session keyring */
 
 extern void key_revoke(struct key *key);
 extern void key_invalidate(struct key *key);
diff --git a/include/xen/swiotlb-xen.h b/include/xen/swiotlb-xen.h
index 8b2eb93ae8ba..4d7fdbf20eff 100644
--- a/include/xen/swiotlb-xen.h
+++ b/include/xen/swiotlb-xen.h
@@ -58,4 +58,9 @@ xen_swiotlb_dma_supported(struct device *hwdev, u64 mask);
 
 extern int
 xen_swiotlb_set_dma_mask(struct device *dev, u64 dma_mask);
+
+extern int
+xen_swiotlb_dma_mmap(struct device *dev, struct vm_area_struct *vma,
+		     void *cpu_addr, dma_addr_t dma_addr, size_t size,
+		     struct dma_attrs *attrs);
 #endif /* __LINUX_SWIOTLB_XEN_H */
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index 941b21f7c8a4..e61b862309af 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -3168,11 +3168,17 @@ static int tracing_open(struct inode *inode, struct file *file)
 	/* If this file was open for write, then erase contents */
 	if ((file->f_mode & FMODE_WRITE) && (file->f_flags & O_TRUNC)) {
 		int cpu = tracing_get_cpu(inode);
+		struct trace_buffer *trace_buf = &tr->trace_buffer;
+
+#ifdef CONFIG_TRACER_MAX_TRACE
+		if (tr->current_trace->print_max)
+			trace_buf = &tr->max_buffer;
+#endif
 
 		if (cpu == RING_BUFFER_ALL_CPUS)
-			tracing_reset_online_cpus(&tr->trace_buffer);
+			tracing_reset_online_cpus(trace_buf);
 		else
-			tracing_reset(&tr->trace_buffer, cpu);
+			tracing_reset(trace_buf, cpu);
 	}
 
 	if (file->f_mode & FMODE_READ) {
@@ -4430,7 +4436,7 @@ static int tracing_wait_pipe(struct file *filp)
 		 *
 		 * iter->pos will be 0 if we haven't read anything.
 		 */
-		if (!tracing_is_on() && iter->pos)
+		if (!tracer_tracing_is_on(iter->tr) && iter->pos)
 			break;
 
 		mutex_unlock(&iter->mutex);
diff --git a/net/mac80211/offchannel.c b/net/mac80211/offchannel.c
index ff20b2ebdb30..a914eaa7ff06 100644
--- a/net/mac80211/offchannel.c
+++ b/net/mac80211/offchannel.c
@@ -469,6 +469,8 @@ void ieee80211_roc_purge(struct ieee80211_local *local,
 	struct ieee80211_roc_work *roc, *tmp;
 	LIST_HEAD(tmp_list);
 
+	flush_work(&local->hw_roc_start);
+
 	mutex_lock(&local->mtx);
 	list_for_each_entry_safe(roc, tmp, &local->roc_list, list) {
 		if (sdata && roc->sdata != sdata)
diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c
index 9fb1dd399788..f843f704c17c 100644
--- a/net/wireless/nl80211.c
+++ b/net/wireless/nl80211.c
@@ -9006,6 +9006,9 @@ static int nl80211_set_rekey_data(struct sk_buff *skb, struct genl_info *info)
 	if (err)
 		return err;
 
+	if (!tb[NL80211_REKEY_DATA_REPLAY_CTR] || !tb[NL80211_REKEY_DATA_KEK] ||
+	    !tb[NL80211_REKEY_DATA_KCK])
+		return -EINVAL;
 	if (nla_len(tb[NL80211_REKEY_DATA_REPLAY_CTR]) != NL80211_REPLAY_CTR_LEN)
 		return -ERANGE;
 	if (nla_len(tb[NL80211_REKEY_DATA_KEK]) != NL80211_KEK_LEN)
diff --git a/security/keys/internal.h b/security/keys/internal.h
index 200e37867336..b87c92ffae68 100644
--- a/security/keys/internal.h
+++ b/security/keys/internal.h
@@ -136,7 +136,7 @@ extern key_ref_t keyring_search_aux(key_ref_t keyring_ref,
 extern key_ref_t search_my_process_keyrings(struct keyring_search_context *ctx);
 extern key_ref_t search_process_keyrings(struct keyring_search_context *ctx);
 
-extern struct key *find_keyring_by_name(const char *name, bool skip_perm_check);
+extern struct key *find_keyring_by_name(const char *name, bool uid_keyring);
 
 extern int install_user_keyrings(void);
 extern int install_thread_keyring_to_cred(struct cred *);
diff --git a/security/keys/key.c b/security/keys/key.c
index 37c268fb5c81..8f67cd3bb999 100644
--- a/security/keys/key.c
+++ b/security/keys/key.c
@@ -298,6 +298,8 @@ struct key *key_alloc(struct key_type *type, const char *desc,
 		key->flags |= 1 << KEY_FLAG_IN_QUOTA;
 	if (flags & KEY_ALLOC_TRUSTED)
 		key->flags |= 1 << KEY_FLAG_TRUSTED;
+	if (flags & KEY_ALLOC_UID_KEYRING)
+		key->flags |= 1 << KEY_FLAG_UID_KEYRING;
 
 #ifdef KEY_DEBUGGING
 	key->magic = KEY_DEBUG_MAGIC;
diff --git a/security/keys/keyctl.c b/security/keys/keyctl.c
index 98c5ebc6dad6..9fc289ec0159 100644
--- a/security/keys/keyctl.c
+++ b/security/keys/keyctl.c
@@ -744,6 +744,11 @@ long keyctl_read_key(key_serial_t keyid, char __user *buffer, size_t buflen)
 
 	key = key_ref_to_ptr(key_ref);
 
+	if (test_bit(KEY_FLAG_NEGATIVE, &key->flags)) {
+		ret = -ENOKEY;
+		goto error2;
+	}
+
 	/* see if we can read it directly */
 	ret = key_permission(key_ref, KEY_NEED_READ);
 	if (ret == 0)
diff --git a/security/keys/keyring.c b/security/keys/keyring.c
index d33437007ad2..6d913f40b6f0 100644
--- a/security/keys/keyring.c
+++ b/security/keys/keyring.c
@@ -416,7 +416,7 @@ static void keyring_describe(const struct key *keyring, struct seq_file *m)
 }
 
 struct keyring_read_iterator_context {
-	size_t			qty;
+	size_t			buflen;
 	size_t			count;
 	key_serial_t __user	*buffer;
 };
@@ -428,9 +428,9 @@ static int keyring_read_iterator(const void *object, void *data)
 	int ret;
 
 	kenter("{%s,%d},,{%zu/%zu}",
-	       key->type->name, key->serial, ctx->count, ctx->qty);
+	       key->type->name, key->serial, ctx->count, ctx->buflen);
 
-	if (ctx->count >= ctx->qty)
+	if (ctx->count >= ctx->buflen)
 		return 1;
 
 	ret = put_user(key->serial, ctx->buffer);
@@ -465,16 +465,12 @@ static long keyring_read(const struct key *keyring,
 		return 0;
 
 	/* Calculate how much data we could return */
-	ctx.qty = nr_keys * sizeof(key_serial_t);
-
 	if (!buffer || !buflen)
-		return ctx.qty;
-
-	if (buflen > ctx.qty)
-		ctx.qty = buflen;
+		return nr_keys * sizeof(key_serial_t);
 
 	/* Copy the IDs of the subscribed keys into the buffer */
 	ctx.buffer = (key_serial_t __user *)buffer;
+	ctx.buflen = buflen;
 	ctx.count = 0;
 	ret = assoc_array_iterate(&keyring->keys, keyring_read_iterator, &ctx);
 	if (ret < 0) {
@@ -965,15 +961,15 @@ found:
 /*
  * Find a keyring with the specified name.
  *
- * All named keyrings in the current user namespace are searched, provided they
- * grant Search permission directly to the caller (unless this check is
- * skipped).  Keyrings whose usage points have reached zero or who have been
- * revoked are skipped.
+ * Only keyrings that have nonzero refcount, are not revoked, and are owned by a
+ * user in the current user namespace are considered.  If @uid_keyring is %true,
+ * the keyring additionally must have been allocated as a user or user session
+ * keyring; otherwise, it must grant Search permission directly to the caller.
  *
  * Returns a pointer to the keyring with the keyring's refcount having being
  * incremented on success.  -ENOKEY is returned if a key could not be found.
  */
-struct key *find_keyring_by_name(const char *name, bool skip_perm_check)
+struct key *find_keyring_by_name(const char *name, bool uid_keyring)
 {
 	struct key *keyring;
 	int bucket;
@@ -1001,10 +997,15 @@ struct key *find_keyring_by_name(const char *name, bool skip_perm_check)
 			if (strcmp(keyring->description, name) != 0)
 				continue;
 
-			if (!skip_perm_check &&
-			    key_permission(make_key_ref(keyring, 0),
-					   KEY_NEED_SEARCH) < 0)
-				continue;
+			if (uid_keyring) {
+				if (!test_bit(KEY_FLAG_UID_KEYRING,
+					      &keyring->flags))
+					continue;
+			} else {
+				if (key_permission(make_key_ref(keyring, 0),
+						   KEY_NEED_SEARCH) < 0)
+					continue;
+			}
 
 			/* we've got a match but we might end up racing with
 			 * key_cleanup() if the keyring is currently 'dead'
diff --git a/security/keys/process_keys.c b/security/keys/process_keys.c
index 162077db5f81..85b61a3ac981 100644
--- a/security/keys/process_keys.c
+++ b/security/keys/process_keys.c
@@ -76,7 +76,9 @@ int install_user_keyrings(void)
 		if (IS_ERR(uid_keyring)) {
 			uid_keyring = keyring_alloc(buf, user->uid, INVALID_GID,
 						    cred, user_keyring_perm,
-						    KEY_ALLOC_IN_QUOTA, NULL);
+						    KEY_ALLOC_UID_KEYRING |
+							KEY_ALLOC_IN_QUOTA,
+						    NULL);
 			if (IS_ERR(uid_keyring)) {
 				ret = PTR_ERR(uid_keyring);
 				goto error;
@@ -92,7 +94,9 @@ int install_user_keyrings(void)
 			session_keyring =
 				keyring_alloc(buf, user->uid, INVALID_GID,
 					      cred, user_keyring_perm,
-					      KEY_ALLOC_IN_QUOTA, NULL);
+					      KEY_ALLOC_UID_KEYRING |
+						  KEY_ALLOC_IN_QUOTA,
+					      NULL);
 			if (IS_ERR(session_keyring)) {
 				ret = PTR_ERR(session_keyring);
 				goto error_release;