[PATCH AUTOSEL 4.9 1/6] dmaengine: ti: dma-crossbar: Fix a memory leak bug

[PATCH AUTOSEL 4.9 1/6] dmaengine: ti: dma-crossbar: Fix a memory leak bug

[Sasha Levin]

From: Wenwen Wang <wenwen@cs.uga.edu>

[ Upstream commit 2c231c0c1dec42192aca0f87f2dc68b8f0cbc7d2 ]

In ti_dra7_xbar_probe(), 'rsv_events' is allocated through kcalloc(). Then
of_property_read_u32_array() is invoked to search for the property.
However, if this process fails, 'rsv_events' is not deallocated, leading to
a memory leak bug. To fix this issue, free 'rsv_events' before returning
the error.

Signed-off-by: Wenwen Wang <wenwen@cs.uga.edu>
Acked-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Link: https://lore.kernel.org/r/1565938136-7249-1-git-send-email-wenwen@cs.uga.edu
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/dma/ti-dma-crossbar.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/dma/ti-dma-crossbar.c b/drivers/dma/ti-dma-crossbar.c
index 8c3c588834d2e..a7e1f6e17e3d1 100644
--- a/drivers/dma/ti-dma-crossbar.c
+++ b/drivers/dma/ti-dma-crossbar.c
@@ -395,8 +395,10 @@ static int ti_dra7_xbar_probe(struct platform_device *pdev)
 
 		ret = of_property_read_u32_array(node, pname, (u32 *)rsv_events,
 						 nelm * 2);
-		if (ret)
+		if (ret) {
+			kfree(rsv_events);
 			return ret;
+		}
 
 		for (i = 0; i < nelm; i++) {
 			ti_dra7_xbar_reserve(rsv_events[i][0], rsv_events[i][1],
-- 
2.20.1

[PATCH AUTOSEL 4.9 2/6] dmaengine: ti: omap-dma: Add cleanup in omap_dma_probe()

[Sasha Levin]

From: Wenwen Wang <wenwen@cs.uga.edu>

[ Upstream commit 962411b05a6d3342aa649e39cda1704c1fc042c6 ]

If devm_request_irq() fails to disable all interrupts, no cleanup is
performed before retuning the error. To fix this issue, invoke
omap_dma_free() to do the cleanup.

Signed-off-by: Wenwen Wang <wenwen@cs.uga.edu>
Acked-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Link: https://lore.kernel.org/r/1565938570-7528-1-git-send-email-wenwen@cs.uga.edu
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/dma/omap-dma.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/dma/omap-dma.c b/drivers/dma/omap-dma.c
index 6b16ce390dce1..9f901f16bddcd 100644
--- a/drivers/dma/omap-dma.c
+++ b/drivers/dma/omap-dma.c
@@ -1429,8 +1429,10 @@ static int omap_dma_probe(struct platform_device *pdev)
 
 		rc = devm_request_irq(&pdev->dev, irq, omap_dma_irq,
 				      IRQF_SHARED, "omap-dma-engine", od);
-		if (rc)
+		if (rc) {
+			omap_dma_free(od);
 			return rc;
+		}
 	}
 
 	if (omap_dma_glbl_read(od, CAPS_0) & CAPS_0_SUPPORT_LL123)
-- 
2.20.1

[PATCH AUTOSEL 4.9 3/6] x86/uaccess: Don't leak the AC flags into __get_user() argument evaluation

[Sasha Levin]

From: Peter Zijlstra <peterz@infradead.org>

[ Upstream commit 9b8bd476e78e89c9ea26c3b435ad0201c3d7dbf5 ]

Identical to __put_user(); the __get_user() argument evalution will too
leak UBSAN crud into the __uaccess_begin() / __uaccess_end() region.
While uncommon this was observed to happen for:

  drivers/xen/gntdev.c: if (__get_user(old_status, batch->status[i]))

where UBSAN added array bound checking.

This complements commit:

  6ae865615fc4 ("x86/uaccess: Dont leak the AC flag into __put_user() argument evaluation")

Tested-by Sedat Dilek <sedat.dilek@gmail.com>
Reported-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Cc: broonie@kernel.org
Cc: sfr@canb.auug.org.au
Cc: akpm@linux-foundation.org
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: mhocko@suse.cz
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Link: https://lkml.kernel.org/r/20190829082445.GM2369@hirez.programming.kicks-ass.net
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 arch/x86/include/asm/uaccess.h | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/arch/x86/include/asm/uaccess.h b/arch/x86/include/asm/uaccess.h
index 2177c7551ff77..9db8d8758ed3b 100644
--- a/arch/x86/include/asm/uaccess.h
+++ b/arch/x86/include/asm/uaccess.h
@@ -438,8 +438,10 @@ do {									\
 ({									\
 	int __gu_err;							\
 	__inttype(*(ptr)) __gu_val;					\
+	__typeof__(ptr) __gu_ptr = (ptr);				\
+	__typeof__(size) __gu_size = (size);				\
 	__uaccess_begin_nospec();					\
-	__get_user_size(__gu_val, (ptr), (size), __gu_err, -EFAULT);	\
+	__get_user_size(__gu_val, __gu_ptr, __gu_size, __gu_err, -EFAULT);	\
 	__uaccess_end();						\
 	(x) = (__force __typeof__(*(ptr)))__gu_val;			\
 	__builtin_expect(__gu_err, 0);					\
-- 
2.20.1

[PATCH AUTOSEL 4.9 4/6] configfs_register_group() shouldn't be (and isn't) called in rmdirable parts

[Sasha Levin]

From: Al Viro <viro@zeniv.linux.org.uk>

[ Upstream commit f19e4ed1e1edbfa3c9ccb9fed17759b7d6db24c6 ]

revert cc57c07343bd "configfs: fix registered group removal"
It was an attempt to handle something that fundamentally doesn't
work - configfs_register_group() should never be done in a part
of tree that can be rmdir'ed.  And in mainline it never had been,
so let's not borrow trouble; the fix was racy anyway, it would take
a lot more to make that work and desired semantics is not clear.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 fs/configfs/dir.c | 11 -----------
 1 file changed, 11 deletions(-)

diff --git a/fs/configfs/dir.c b/fs/configfs/dir.c
index a1985a9ad2d64..64fdb12e6ad61 100644
--- a/fs/configfs/dir.c
+++ b/fs/configfs/dir.c
@@ -1782,16 +1782,6 @@ void configfs_unregister_group(struct config_group *group)
 	struct dentry *dentry = group->cg_item.ci_dentry;
 	struct dentry *parent = group->cg_item.ci_parent->ci_dentry;
 
-	mutex_lock(&subsys->su_mutex);
-	if (!group->cg_item.ci_parent->ci_group) {
-		/*
-		 * The parent has already been unlinked and detached
-		 * due to a rmdir.
-		 */
-		goto unlink_group;
-	}
-	mutex_unlock(&subsys->su_mutex);
-
 	inode_lock_nested(d_inode(parent), I_MUTEX_PARENT);
 	spin_lock(&configfs_dirent_lock);
 	configfs_detach_prep(dentry, NULL);
@@ -1806,7 +1796,6 @@ void configfs_unregister_group(struct config_group *group)
 	dput(dentry);
 
 	mutex_lock(&subsys->su_mutex);
-unlink_group:
 	unlink_group(group);
 	mutex_unlock(&subsys->su_mutex);
 }
-- 
2.20.1

[PATCH AUTOSEL 4.9 5/6] keys: Fix missing null pointer check in request_key_auth_describe()

[Sasha Levin]

From: Hillf Danton <hdanton@sina.com>

[ Upstream commit d41a3effbb53b1bcea41e328d16a4d046a508381 ]

If a request_key authentication token key gets revoked, there's a window in
which request_key_auth_describe() can see it with a NULL payload - but it
makes no check for this and something like the following oops may occur:

	BUG: Kernel NULL pointer dereference at 0x00000038
	Faulting instruction address: 0xc0000000004ddf30
	Oops: Kernel access of bad area, sig: 11 [#1]
	...
	NIP [...] request_key_auth_describe+0x90/0xd0
	LR [...] request_key_auth_describe+0x54/0xd0
	Call Trace:
	[...] request_key_auth_describe+0x54/0xd0 (unreliable)
	[...] proc_keys_show+0x308/0x4c0
	[...] seq_read+0x3d0/0x540
	[...] proc_reg_read+0x90/0x110
	[...] __vfs_read+0x3c/0x70
	[...] vfs_read+0xb4/0x1b0
	[...] ksys_read+0x7c/0x130
	[...] system_call+0x5c/0x70

Fix this by checking for a NULL pointer when describing such a key.

Also make the read routine check for a NULL pointer to be on the safe side.

[DH: Modified to not take already-held rcu lock and modified to also check
 in the read routine]

Fixes: 04c567d9313e ("[PATCH] Keys: Fix race between two instantiators of a key")
Reported-by: Sachin Sant <sachinp@linux.vnet.ibm.com>
Signed-off-by: Hillf Danton <hdanton@sina.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Tested-by: Sachin Sant <sachinp@linux.vnet.ibm.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 security/keys/request_key_auth.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/security/keys/request_key_auth.c b/security/keys/request_key_auth.c
index f60baeb338e5f..b47445022d5ce 100644
--- a/security/keys/request_key_auth.c
+++ b/security/keys/request_key_auth.c
@@ -71,6 +71,9 @@ static void request_key_auth_describe(const struct key *key,
 {
 	struct request_key_auth *rka = key->payload.data[0];
 
+	if (!rka)
+		return;
+
 	seq_puts(m, "key:");
 	seq_puts(m, key->description);
 	if (key_is_positive(key))
@@ -88,6 +91,9 @@ static long request_key_auth_read(const struct key *key,
 	size_t datalen;
 	long ret;
 
+	if (!rka)
+		return -EKEYREVOKED;
+
 	datalen = rka->callout_len;
 	ret = datalen;
 
-- 
2.20.1

[PATCH AUTOSEL 4.9 6/6] iommu/amd: Fix race in increase_address_space()

[Sasha Levin]

From: Joerg Roedel <jroedel@suse.de>

[ Upstream commit 754265bcab78a9014f0f99cd35e0d610fcd7dfa7 ]

After the conversion to lock-less dma-api call the
increase_address_space() function can be called without any
locking. Multiple CPUs could potentially race for increasing
the address space, leading to invalid domain->mode settings
and invalid page-tables. This has been happening in the wild
under high IO load and memory pressure.

Fix the race by locking this operation. The function is
called infrequently so that this does not introduce
a performance regression in the dma-api path again.

Reported-by: Qian Cai <cai@lca.pw>
Fixes: 256e4621c21a ('iommu/amd: Make use of the generic IOVA allocator')
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/iommu/amd_iommu.c | 16 +++++++++++-----
 1 file changed, 11 insertions(+), 5 deletions(-)

diff --git a/drivers/iommu/amd_iommu.c b/drivers/iommu/amd_iommu.c
index c1233d0288a03..dd7880de7e4e9 100644
--- a/drivers/iommu/amd_iommu.c
+++ b/drivers/iommu/amd_iommu.c
@@ -1321,18 +1321,21 @@ static void domain_flush_devices(struct protection_domain *domain)
  * another level increases the size of the address space by 9 bits to a size up
  * to 64 bits.
  */
-static bool increase_address_space(struct protection_domain *domain,
+static void increase_address_space(struct protection_domain *domain,
 				   gfp_t gfp)
 {
+	unsigned long flags;
 	u64 *pte;
 
-	if (domain->mode == PAGE_MODE_6_LEVEL)
+	spin_lock_irqsave(&domain->lock, flags);
+
+	if (WARN_ON_ONCE(domain->mode == PAGE_MODE_6_LEVEL))
 		/* address space already 64 bit large */
-		return false;
+		goto out;
 
 	pte = (void *)get_zeroed_page(gfp);
 	if (!pte)
-		return false;
+		goto out;
 
 	*pte             = PM_LEVEL_PDE(domain->mode,
 					virt_to_phys(domain->pt_root));
@@ -1340,7 +1343,10 @@ static bool increase_address_space(struct protection_domain *domain,
 	domain->mode    += 1;
 	domain->updated  = true;
 
-	return true;
+out:
+	spin_unlock_irqrestore(&domain->lock, flags);
+
+	return;
 }
 
 static u64 *alloc_pte(struct protection_domain *domain,
-- 
2.20.1