This is a note to let you know that I've just added the patch titled
selftests/x86: Add tests for User-Mode Instruction Prevention
to the 4.4-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=sum…
The filename of the patch is:
selftests-x86-add-tests-for-user-mode-instruction-prevention.patch
and it can be found in the queue-4.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable(a)vger.kernel.org> know about it.
>From 9390afebe1d3f5a0be18b1afdd0ce09d67cebf9e Mon Sep 17 00:00:00 2001
From: Ricardo Neri <ricardo.neri-calderon(a)linux.intel.com>
Date: Sun, 5 Nov 2017 18:27:56 -0800
Subject: selftests/x86: Add tests for User-Mode Instruction Prevention
From: Ricardo Neri <ricardo.neri-calderon(a)linux.intel.com>
commit 9390afebe1d3f5a0be18b1afdd0ce09d67cebf9e upstream.
Certain user space programs that run on virtual-8086 mode may utilize
instructions protected by the User-Mode Instruction Prevention (UMIP)
security feature present in new Intel processors: SGDT, SIDT and SMSW. In
such a case, a general protection fault is issued if UMIP is enabled. When
such a fault happens, the kernel traps it and emulates the results of
these instructions with dummy values. The purpose of this new
test is to verify whether the impacted instructions can be executed
without causing such #GP. If no #GP exceptions occur, we expect to exit
virtual-8086 mode from INT3.
The instructions protected by UMIP are executed in representative use
cases:
a) displacement-only memory addressing
b) register-indirect memory addressing
c) results stored directly in operands
Unfortunately, it is not possible to check the results against a set of
expected values because no emulation will occur in systems that do not
have the UMIP feature. Instead, results are printed for verification. A
simple verification is done to ensure that results of all tests are
identical.
Signed-off-by: Ricardo Neri <ricardo.neri-calderon(a)linux.intel.com>
Reviewed-by: Thomas Gleixner <tglx(a)linutronix.de>
Cc: Andrew Morton <akpm(a)linux-foundation.org>
Cc: Andy Lutomirski <luto(a)kernel.org>
Cc: Borislav Petkov <bp(a)alien8.de>
Cc: Borislav Petkov <bp(a)suse.de>
Cc: Brian Gerst <brgerst(a)gmail.com>
Cc: Chen Yucong <slaoub(a)gmail.com>
Cc: Chris Metcalf <cmetcalf(a)mellanox.com>
Cc: Dave Hansen <dave.hansen(a)linux.intel.com>
Cc: Denys Vlasenko <dvlasenk(a)redhat.com>
Cc: Fenghua Yu <fenghua.yu(a)intel.com>
Cc: H. Peter Anvin <hpa(a)zytor.com>
Cc: Huang Rui <ray.huang(a)amd.com>
Cc: Jiri Slaby <jslaby(a)suse.cz>
Cc: Jonathan Corbet <corbet(a)lwn.net>
Cc: Josh Poimboeuf <jpoimboe(a)redhat.com>
Cc: Linus Torvalds <torvalds(a)linux-foundation.org>
Cc: Masami Hiramatsu <mhiramat(a)kernel.org>
Cc: Michael S. Tsirkin <mst(a)redhat.com>
Cc: Paolo Bonzini <pbonzini(a)redhat.com>
Cc: Paul Gortmaker <paul.gortmaker(a)windriver.com>
Cc: Peter Zijlstra <peterz(a)infradead.org>
Cc: Ravi V. Shankar <ravi.v.shankar(a)intel.com>
Cc: Shuah Khan <shuah(a)kernel.org>
Cc: Tony Luck <tony.luck(a)intel.com>
Cc: Vlastimil Babka <vbabka(a)suse.cz>
Cc: ricardo.neri(a)intel.com
Link: http://lkml.kernel.org/r/1509935277-22138-12-git-send-email-ricardo.neri-ca…
Signed-off-by: Ingo Molnar <mingo(a)kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
---
tools/testing/selftests/x86/entry_from_vm86.c | 73 +++++++++++++++++++++++++-
1 file changed, 72 insertions(+), 1 deletion(-)
--- a/tools/testing/selftests/x86/entry_from_vm86.c
+++ b/tools/testing/selftests/x86/entry_from_vm86.c
@@ -95,6 +95,22 @@ asm (
"int3\n\t"
"vmcode_int80:\n\t"
"int $0x80\n\t"
+ "vmcode_umip:\n\t"
+ /* addressing via displacements */
+ "smsw (2052)\n\t"
+ "sidt (2054)\n\t"
+ "sgdt (2060)\n\t"
+ /* addressing via registers */
+ "mov $2066, %bx\n\t"
+ "smsw (%bx)\n\t"
+ "mov $2068, %bx\n\t"
+ "sidt (%bx)\n\t"
+ "mov $2074, %bx\n\t"
+ "sgdt (%bx)\n\t"
+ /* register operands, only for smsw */
+ "smsw %ax\n\t"
+ "mov %ax, (2080)\n\t"
+ "int3\n\t"
".size vmcode, . - vmcode\n\t"
"end_vmcode:\n\t"
".code32\n\t"
@@ -103,7 +119,7 @@ asm (
extern unsigned char vmcode[], end_vmcode[];
extern unsigned char vmcode_bound[], vmcode_sysenter[], vmcode_syscall[],
- vmcode_sti[], vmcode_int3[], vmcode_int80[];
+ vmcode_sti[], vmcode_int3[], vmcode_int80[], vmcode_umip[];
/* Returns false if the test was skipped. */
static bool do_test(struct vm86plus_struct *v86, unsigned long eip,
@@ -160,6 +176,58 @@ static bool do_test(struct vm86plus_stru
return true;
}
+void do_umip_tests(struct vm86plus_struct *vm86, unsigned char *test_mem)
+{
+ struct table_desc {
+ unsigned short limit;
+ unsigned long base;
+ } __attribute__((packed));
+
+ /* Initialize variables with arbitrary values */
+ struct table_desc gdt1 = { .base = 0x3c3c3c3c, .limit = 0x9999 };
+ struct table_desc gdt2 = { .base = 0x1a1a1a1a, .limit = 0xaeae };
+ struct table_desc idt1 = { .base = 0x7b7b7b7b, .limit = 0xf1f1 };
+ struct table_desc idt2 = { .base = 0x89898989, .limit = 0x1313 };
+ unsigned short msw1 = 0x1414, msw2 = 0x2525, msw3 = 3737;
+
+ /* UMIP -- exit with INT3 unless kernel emulation did not trap #GP */
+ do_test(vm86, vmcode_umip - vmcode, VM86_TRAP, 3, "UMIP tests");
+
+ /* Results from displacement-only addressing */
+ msw1 = *(unsigned short *)(test_mem + 2052);
+ memcpy(&idt1, test_mem + 2054, sizeof(idt1));
+ memcpy(&gdt1, test_mem + 2060, sizeof(gdt1));
+
+ /* Results from register-indirect addressing */
+ msw2 = *(unsigned short *)(test_mem + 2066);
+ memcpy(&idt2, test_mem + 2068, sizeof(idt2));
+ memcpy(&gdt2, test_mem + 2074, sizeof(gdt2));
+
+ /* Results when using register operands */
+ msw3 = *(unsigned short *)(test_mem + 2080);
+
+ printf("[INFO]\tResult from SMSW:[0x%04x]\n", msw1);
+ printf("[INFO]\tResult from SIDT: limit[0x%04x]base[0x%08lx]\n",
+ idt1.limit, idt1.base);
+ printf("[INFO]\tResult from SGDT: limit[0x%04x]base[0x%08lx]\n",
+ gdt1.limit, gdt1.base);
+
+ if (msw1 != msw2 || msw1 != msw3)
+ printf("[FAIL]\tAll the results of SMSW should be the same.\n");
+ else
+ printf("[PASS]\tAll the results from SMSW are identical.\n");
+
+ if (memcmp(&gdt1, &gdt2, sizeof(gdt1)))
+ printf("[FAIL]\tAll the results of SGDT should be the same.\n");
+ else
+ printf("[PASS]\tAll the results from SGDT are identical.\n");
+
+ if (memcmp(&idt1, &idt2, sizeof(idt1)))
+ printf("[FAIL]\tAll the results of SIDT should be the same.\n");
+ else
+ printf("[PASS]\tAll the results from SIDT are identical.\n");
+}
+
int main(void)
{
struct vm86plus_struct v86;
@@ -218,6 +286,9 @@ int main(void)
v86.regs.eax = (unsigned int)-1;
do_test(&v86, vmcode_int80 - vmcode, VM86_INTx, 0x80, "int80");
+ /* UMIP -- should exit with INTx 0x80 unless UMIP was not disabled */
+ do_umip_tests(&v86, addr);
+
/* Execute a null pointer */
v86.regs.cs = 0;
v86.regs.ss = 0;
Patches currently in stable-queue which might be from ricardo.neri-calderon(a)linux.intel.com are
queue-4.4/selftests-x86-add-tests-for-the-str-and-sldt-instructions.patch
queue-4.4/selftests-x86-add-tests-for-user-mode-instruction-prevention.patch
This is a note to let you know that I've just added the patch titled
selftests/x86: Add tests for the STR and SLDT instructions
to the 4.4-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=sum…
The filename of the patch is:
selftests-x86-add-tests-for-the-str-and-sldt-instructions.patch
and it can be found in the queue-4.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable(a)vger.kernel.org> know about it.
>From a9e017d5619eb371460c8e516f4684def62bef3a Mon Sep 17 00:00:00 2001
From: Ricardo Neri <ricardo.neri-calderon(a)linux.intel.com>
Date: Sun, 5 Nov 2017 18:27:57 -0800
Subject: selftests/x86: Add tests for the STR and SLDT instructions
From: Ricardo Neri <ricardo.neri-calderon(a)linux.intel.com>
commit a9e017d5619eb371460c8e516f4684def62bef3a upstream.
The STR and SLDT instructions are not valid when running on virtual-8086
mode and generate an invalid operand exception. These two instructions are
protected by the Intel User-Mode Instruction Prevention (UMIP) security
feature. In protected mode, if UMIP is enabled, these instructions generate
a general protection fault if called from CPL > 0. Linux traps the general
protection fault and emulates the instructions sgdt, sidt and smsw; but not
str and sldt.
These tests are added to verify that the emulation code does not emulate
these two instructions but the expected invalid operand exception is
seen.
Tests fallback to exit with INT3 in case emulation does happen.
Signed-off-by: Ricardo Neri <ricardo.neri-calderon(a)linux.intel.com>
Reviewed-by: Thomas Gleixner <tglx(a)linutronix.de>
Cc: Andrew Morton <akpm(a)linux-foundation.org>
Cc: Andy Lutomirski <luto(a)kernel.org>
Cc: Borislav Petkov <bp(a)alien8.de>
Cc: Borislav Petkov <bp(a)suse.de>
Cc: Brian Gerst <brgerst(a)gmail.com>
Cc: Chen Yucong <slaoub(a)gmail.com>
Cc: Chris Metcalf <cmetcalf(a)mellanox.com>
Cc: Dave Hansen <dave.hansen(a)linux.intel.com>
Cc: Denys Vlasenko <dvlasenk(a)redhat.com>
Cc: Fenghua Yu <fenghua.yu(a)intel.com>
Cc: H. Peter Anvin <hpa(a)zytor.com>
Cc: Huang Rui <ray.huang(a)amd.com>
Cc: Jiri Slaby <jslaby(a)suse.cz>
Cc: Jonathan Corbet <corbet(a)lwn.net>
Cc: Josh Poimboeuf <jpoimboe(a)redhat.com>
Cc: Linus Torvalds <torvalds(a)linux-foundation.org>
Cc: Masami Hiramatsu <mhiramat(a)kernel.org>
Cc: Michael S. Tsirkin <mst(a)redhat.com>
Cc: Paolo Bonzini <pbonzini(a)redhat.com>
Cc: Paul Gortmaker <paul.gortmaker(a)windriver.com>
Cc: Peter Zijlstra <peterz(a)infradead.org>
Cc: Ravi V. Shankar <ravi.v.shankar(a)intel.com>
Cc: Shuah Khan <shuah(a)kernel.org>
Cc: Tony Luck <tony.luck(a)intel.com>
Cc: Vlastimil Babka <vbabka(a)suse.cz>
Cc: ricardo.neri(a)intel.com
Link: http://lkml.kernel.org/r/1509935277-22138-13-git-send-email-ricardo.neri-ca…
Signed-off-by: Ingo Molnar <mingo(a)kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
---
tools/testing/selftests/x86/entry_from_vm86.c | 18 +++++++++++++++++-
1 file changed, 17 insertions(+), 1 deletion(-)
--- a/tools/testing/selftests/x86/entry_from_vm86.c
+++ b/tools/testing/selftests/x86/entry_from_vm86.c
@@ -111,6 +111,11 @@ asm (
"smsw %ax\n\t"
"mov %ax, (2080)\n\t"
"int3\n\t"
+ "vmcode_umip_str:\n\t"
+ "str %eax\n\t"
+ "vmcode_umip_sldt:\n\t"
+ "sldt %eax\n\t"
+ "int3\n\t"
".size vmcode, . - vmcode\n\t"
"end_vmcode:\n\t"
".code32\n\t"
@@ -119,7 +124,8 @@ asm (
extern unsigned char vmcode[], end_vmcode[];
extern unsigned char vmcode_bound[], vmcode_sysenter[], vmcode_syscall[],
- vmcode_sti[], vmcode_int3[], vmcode_int80[], vmcode_umip[];
+ vmcode_sti[], vmcode_int3[], vmcode_int80[], vmcode_umip[],
+ vmcode_umip_str[], vmcode_umip_sldt[];
/* Returns false if the test was skipped. */
static bool do_test(struct vm86plus_struct *v86, unsigned long eip,
@@ -226,6 +232,16 @@ void do_umip_tests(struct vm86plus_struc
printf("[FAIL]\tAll the results of SIDT should be the same.\n");
else
printf("[PASS]\tAll the results from SIDT are identical.\n");
+
+ sethandler(SIGILL, sighandler, 0);
+ do_test(vm86, vmcode_umip_str - vmcode, VM86_SIGNAL, 0,
+ "STR instruction");
+ clearhandler(SIGILL);
+
+ sethandler(SIGILL, sighandler, 0);
+ do_test(vm86, vmcode_umip_sldt - vmcode, VM86_SIGNAL, 0,
+ "SLDT instruction");
+ clearhandler(SIGILL);
}
int main(void)
Patches currently in stable-queue which might be from ricardo.neri-calderon(a)linux.intel.com are
queue-4.4/selftests-x86-add-tests-for-the-str-and-sldt-instructions.patch
queue-4.4/selftests-x86-add-tests-for-user-mode-instruction-prevention.patch
This is a note to let you know that I've just added the patch titled
lock_parent() needs to recheck if dentry got __dentry_kill'ed under it
to the 4.4-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=sum…
The filename of the patch is:
lock_parent-needs-to-recheck-if-dentry-got-__dentry_kill-ed-under-it.patch
and it can be found in the queue-4.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable(a)vger.kernel.org> know about it.
>From 3b821409632ab778d46e807516b457dfa72736ed Mon Sep 17 00:00:00 2001
From: Al Viro <viro(a)zeniv.linux.org.uk>
Date: Fri, 23 Feb 2018 20:47:17 -0500
Subject: lock_parent() needs to recheck if dentry got __dentry_kill'ed under it
From: Al Viro <viro(a)zeniv.linux.org.uk>
commit 3b821409632ab778d46e807516b457dfa72736ed upstream.
In case when dentry passed to lock_parent() is protected from freeing only
by the fact that it's on a shrink list and trylock of parent fails, we
could get hit by __dentry_kill() (and subsequent dentry_kill(parent))
between unlocking dentry and locking presumed parent. We need to recheck
that dentry is alive once we lock both it and parent *and* postpone
rcu_read_unlock() until after that point. Otherwise we could return
a pointer to struct dentry that already is rcu-scheduled for freeing, with
->d_lock held on it; caller's subsequent attempt to unlock it can end
up with memory corruption.
Cc: stable(a)vger.kernel.org # 3.12+, counting backports
Signed-off-by: Al Viro <viro(a)zeniv.linux.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
---
fs/dcache.c | 11 ++++++++---
1 file changed, 8 insertions(+), 3 deletions(-)
--- a/fs/dcache.c
+++ b/fs/dcache.c
@@ -634,11 +634,16 @@ again:
spin_unlock(&parent->d_lock);
goto again;
}
- rcu_read_unlock();
- if (parent != dentry)
+ if (parent != dentry) {
spin_lock_nested(&dentry->d_lock, DENTRY_D_LOCK_NESTED);
- else
+ if (unlikely(dentry->d_lockref.count < 0)) {
+ spin_unlock(&parent->d_lock);
+ parent = NULL;
+ }
+ } else {
parent = NULL;
+ }
+ rcu_read_unlock();
return parent;
}
Patches currently in stable-queue which might be from viro(a)zeniv.linux.org.uk are
queue-4.4/fs-teach-path_connected-to-handle-nfs-filesystems-with-multiple-roots.patch
queue-4.4/lock_parent-needs-to-recheck-if-dentry-got-__dentry_kill-ed-under-it.patch
This is a note to let you know that I've just added the patch titled
fs: Teach path_connected to handle nfs filesystems with multiple roots.
to the 4.4-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=sum…
The filename of the patch is:
fs-teach-path_connected-to-handle-nfs-filesystems-with-multiple-roots.patch
and it can be found in the queue-4.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable(a)vger.kernel.org> know about it.
>From 95dd77580ccd66a0da96e6d4696945b8cea39431 Mon Sep 17 00:00:00 2001
From: "Eric W. Biederman" <ebiederm(a)xmission.com>
Date: Wed, 14 Mar 2018 18:20:29 -0500
Subject: fs: Teach path_connected to handle nfs filesystems with multiple roots.
From: Eric W. Biederman <ebiederm(a)xmission.com>
commit 95dd77580ccd66a0da96e6d4696945b8cea39431 upstream.
On nfsv2 and nfsv3 the nfs server can export subsets of the same
filesystem and report the same filesystem identifier, so that the nfs
client can know they are the same filesystem. The subsets can be from
disjoint directory trees. The nfsv2 and nfsv3 filesystems provides no
way to find the common root of all directory trees exported form the
server with the same filesystem identifier.
The practical result is that in struct super s_root for nfs s_root is
not necessarily the root of the filesystem. The nfs mount code sets
s_root to the root of the first subset of the nfs filesystem that the
kernel mounts.
This effects the dcache invalidation code in generic_shutdown_super
currently called shrunk_dcache_for_umount and that code for years
has gone through an additional list of dentries that might be dentry
trees that need to be freed to accomodate nfs.
When I wrote path_connected I did not realize nfs was so special, and
it's hueristic for avoiding calling is_subdir can fail.
The practical case where this fails is when there is a move of a
directory from the subtree exposed by one nfs mount to the subtree
exposed by another nfs mount. This move can happen either locally or
remotely. With the remote case requiring that the move directory be cached
before the move and that after the move someone walks the path
to where the move directory now exists and in so doing causes the
already cached directory to be moved in the dcache through the magic
of d_splice_alias.
If someone whose working directory is in the move directory or a
subdirectory and now starts calling .. from the initial mount of nfs
(where s_root == mnt_root), then path_connected as a heuristic will
not bother with the is_subdir check. As s_root really is not the root
of the nfs filesystem this heuristic is wrong, and the path may
actually not be connected and path_connected can fail.
The is_subdir function might be cheap enough that we can call it
unconditionally. Verifying that will take some benchmarking and
the result may not be the same on all kernels this fix needs
to be backported to. So I am avoiding that for now.
Filesystems with snapshots such as nilfs and btrfs do something
similar. But as the directory tree of the snapshots are disjoint
from one another and from the main directory tree rename won't move
things between them and this problem will not occur.
Cc: stable(a)vger.kernel.org
Reported-by: Al Viro <viro(a)ZenIV.linux.org.uk>
Fixes: 397d425dc26d ("vfs: Test for and handle paths that are unreachable from their mnt_root")
Signed-off-by: "Eric W. Biederman" <ebiederm(a)xmission.com>
Signed-off-by: Al Viro <viro(a)zeniv.linux.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
---
fs/namei.c | 5 +++--
fs/nfs/super.c | 2 ++
include/linux/fs.h | 1 +
3 files changed, 6 insertions(+), 2 deletions(-)
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -570,9 +570,10 @@ static int __nd_alloc_stack(struct namei
static bool path_connected(const struct path *path)
{
struct vfsmount *mnt = path->mnt;
+ struct super_block *sb = mnt->mnt_sb;
- /* Only bind mounts can have disconnected paths */
- if (mnt->mnt_root == mnt->mnt_sb->s_root)
+ /* Bind mounts and multi-root filesystems can have disconnected paths */
+ if (!(sb->s_iflags & SB_I_MULTIROOT) && (mnt->mnt_root == sb->s_root))
return true;
return is_subdir(path->dentry, mnt->mnt_root);
--- a/fs/nfs/super.c
+++ b/fs/nfs/super.c
@@ -2581,6 +2581,8 @@ struct dentry *nfs_fs_mount_common(struc
/* initial superblock/root creation */
mount_info->fill_super(s, mount_info);
nfs_get_cache_cookie(s, mount_info->parsed, mount_info->cloned);
+ if (!(server->flags & NFS_MOUNT_UNSHARED))
+ s->s_iflags |= SB_I_MULTIROOT;
}
mntroot = nfs_get_root(s, mount_info->mntfh, dev_name);
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -1295,6 +1295,7 @@ struct mm_struct;
/* sb->s_iflags */
#define SB_I_CGROUPWB 0x00000001 /* cgroup-aware writeback enabled */
#define SB_I_NOEXEC 0x00000002 /* Ignore executables on this fs */
+#define SB_I_MULTIROOT 0x00000008 /* Multiple roots to the dentry tree */
/* Possible states of 'frozen' field */
enum {
Patches currently in stable-queue which might be from ebiederm(a)xmission.com are
queue-4.4/fs-teach-path_connected-to-handle-nfs-filesystems-with-multiple-roots.patch
This is a note to let you know that I've just added the patch titled
fs/aio: Use RCU accessors for kioctx_table->table[]
to the 4.4-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=sum…
The filename of the patch is:
fs-aio-use-rcu-accessors-for-kioctx_table-table.patch
and it can be found in the queue-4.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable(a)vger.kernel.org> know about it.
>From d0264c01e7587001a8c4608a5d1818dba9a4c11a Mon Sep 17 00:00:00 2001
From: Tejun Heo <tj(a)kernel.org>
Date: Wed, 14 Mar 2018 12:10:17 -0700
Subject: fs/aio: Use RCU accessors for kioctx_table->table[]
From: Tejun Heo <tj(a)kernel.org>
commit d0264c01e7587001a8c4608a5d1818dba9a4c11a upstream.
While converting ioctx index from a list to a table, db446a08c23d
("aio: convert the ioctx list to table lookup v3") missed tagging
kioctx_table->table[] as an array of RCU pointers and using the
appropriate RCU accessors. This introduces a small window in the
lookup path where init and access may race.
Mark kioctx_table->table[] with __rcu and use the approriate RCU
accessors when using the field.
Signed-off-by: Tejun Heo <tj(a)kernel.org>
Reported-by: Jann Horn <jannh(a)google.com>
Fixes: db446a08c23d ("aio: convert the ioctx list to table lookup v3")
Cc: Benjamin LaHaise <bcrl(a)kvack.org>
Cc: Linus Torvalds <torvalds(a)linux-foundation.org>
Cc: stable(a)vger.kernel.org # v3.12+
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
---
fs/aio.c | 21 +++++++++++----------
1 file changed, 11 insertions(+), 10 deletions(-)
--- a/fs/aio.c
+++ b/fs/aio.c
@@ -68,9 +68,9 @@ struct aio_ring {
#define AIO_RING_PAGES 8
struct kioctx_table {
- struct rcu_head rcu;
- unsigned nr;
- struct kioctx *table[];
+ struct rcu_head rcu;
+ unsigned nr;
+ struct kioctx __rcu *table[];
};
struct kioctx_cpu {
@@ -327,7 +327,7 @@ static int aio_ring_mremap(struct vm_are
for (i = 0; i < table->nr; i++) {
struct kioctx *ctx;
- ctx = table->table[i];
+ ctx = rcu_dereference(table->table[i]);
if (ctx && ctx->aio_ring_file == file) {
if (!atomic_read(&ctx->dead)) {
ctx->user_id = ctx->mmap_base = vma->vm_start;
@@ -651,9 +651,9 @@ static int ioctx_add_table(struct kioctx
while (1) {
if (table)
for (i = 0; i < table->nr; i++)
- if (!table->table[i]) {
+ if (!rcu_access_pointer(table->table[i])) {
ctx->id = i;
- table->table[i] = ctx;
+ rcu_assign_pointer(table->table[i], ctx);
spin_unlock(&mm->ioctx_lock);
/* While kioctx setup is in progress,
@@ -828,8 +828,8 @@ static int kill_ioctx(struct mm_struct *
}
table = rcu_dereference_raw(mm->ioctx_table);
- WARN_ON(ctx != table->table[ctx->id]);
- table->table[ctx->id] = NULL;
+ WARN_ON(ctx != rcu_access_pointer(table->table[ctx->id]));
+ RCU_INIT_POINTER(table->table[ctx->id], NULL);
spin_unlock(&mm->ioctx_lock);
/* free_ioctx_reqs() will do the necessary RCU synchronization */
@@ -874,7 +874,8 @@ void exit_aio(struct mm_struct *mm)
skipped = 0;
for (i = 0; i < table->nr; ++i) {
- struct kioctx *ctx = table->table[i];
+ struct kioctx *ctx =
+ rcu_dereference_protected(table->table[i], true);
if (!ctx) {
skipped++;
@@ -1063,7 +1064,7 @@ static struct kioctx *lookup_ioctx(unsig
if (!table || id >= table->nr)
goto out;
- ctx = table->table[id];
+ ctx = rcu_dereference(table->table[id]);
if (ctx && ctx->user_id == ctx_id) {
percpu_ref_get(&ctx->users);
ret = ctx;
Patches currently in stable-queue which might be from tj(a)kernel.org are
queue-4.4/fs-aio-add-explicit-rcu-grace-period-when-freeing-kioctx.patch
queue-4.4/fs-aio-use-rcu-accessors-for-kioctx_table-table.patch
This is a note to let you know that I've just added the patch titled
fs/aio: Add explicit RCU grace period when freeing kioctx
to the 4.4-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=sum…
The filename of the patch is:
fs-aio-add-explicit-rcu-grace-period-when-freeing-kioctx.patch
and it can be found in the queue-4.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable(a)vger.kernel.org> know about it.
>From a6d7cff472eea87d96899a20fa718d2bab7109f3 Mon Sep 17 00:00:00 2001
From: Tejun Heo <tj(a)kernel.org>
Date: Wed, 14 Mar 2018 12:10:17 -0700
Subject: fs/aio: Add explicit RCU grace period when freeing kioctx
From: Tejun Heo <tj(a)kernel.org>
commit a6d7cff472eea87d96899a20fa718d2bab7109f3 upstream.
While fixing refcounting, e34ecee2ae79 ("aio: Fix a trinity splat")
incorrectly removed explicit RCU grace period before freeing kioctx.
The intention seems to be depending on the internal RCU grace periods
of percpu_ref; however, percpu_ref uses a different flavor of RCU,
sched-RCU. This can lead to kioctx being freed while RCU read
protected dereferences are still in progress.
Fix it by updating free_ioctx() to go through call_rcu() explicitly.
v2: Comment added to explain double bouncing.
Signed-off-by: Tejun Heo <tj(a)kernel.org>
Reported-by: Jann Horn <jannh(a)google.com>
Fixes: e34ecee2ae79 ("aio: Fix a trinity splat")
Cc: Kent Overstreet <kent.overstreet(a)gmail.com>
Cc: Linus Torvalds <torvalds(a)linux-foundation.org>
Cc: stable(a)vger.kernel.org # v3.13+
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
---
fs/aio.c | 23 +++++++++++++++++++----
1 file changed, 19 insertions(+), 4 deletions(-)
--- a/fs/aio.c
+++ b/fs/aio.c
@@ -115,7 +115,8 @@ struct kioctx {
struct page **ring_pages;
long nr_pages;
- struct work_struct free_work;
+ struct rcu_head free_rcu;
+ struct work_struct free_work; /* see free_ioctx() */
/*
* signals when all in-flight requests are done
@@ -573,6 +574,12 @@ static int kiocb_cancel(struct aio_kiocb
return cancel(&kiocb->common);
}
+/*
+ * free_ioctx() should be RCU delayed to synchronize against the RCU
+ * protected lookup_ioctx() and also needs process context to call
+ * aio_free_ring(), so the double bouncing through kioctx->free_rcu and
+ * ->free_work.
+ */
static void free_ioctx(struct work_struct *work)
{
struct kioctx *ctx = container_of(work, struct kioctx, free_work);
@@ -586,6 +593,14 @@ static void free_ioctx(struct work_struc
kmem_cache_free(kioctx_cachep, ctx);
}
+static void free_ioctx_rcufn(struct rcu_head *head)
+{
+ struct kioctx *ctx = container_of(head, struct kioctx, free_rcu);
+
+ INIT_WORK(&ctx->free_work, free_ioctx);
+ schedule_work(&ctx->free_work);
+}
+
static void free_ioctx_reqs(struct percpu_ref *ref)
{
struct kioctx *ctx = container_of(ref, struct kioctx, reqs);
@@ -594,8 +609,8 @@ static void free_ioctx_reqs(struct percp
if (ctx->rq_wait && atomic_dec_and_test(&ctx->rq_wait->count))
complete(&ctx->rq_wait->comp);
- INIT_WORK(&ctx->free_work, free_ioctx);
- schedule_work(&ctx->free_work);
+ /* Synchronize against RCU protected table->table[] dereferences */
+ call_rcu(&ctx->free_rcu, free_ioctx_rcufn);
}
/*
@@ -817,7 +832,7 @@ static int kill_ioctx(struct mm_struct *
table->table[ctx->id] = NULL;
spin_unlock(&mm->ioctx_lock);
- /* percpu_ref_kill() will do the necessary call_rcu() */
+ /* free_ioctx_reqs() will do the necessary RCU synchronization */
wake_up_all(&ctx->wait);
/*
Patches currently in stable-queue which might be from tj(a)kernel.org are
queue-4.4/fs-aio-add-explicit-rcu-grace-period-when-freeing-kioctx.patch
queue-4.4/fs-aio-use-rcu-accessors-for-kioctx_table-table.patch
This is a note to let you know that I've just added the patch titled
ALSA: seq: Fix possible UAF in snd_seq_check_queue()
to the 4.4-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=sum…
The filename of the patch is:
alsa-seq-fix-possible-uaf-in-snd_seq_check_queue.patch
and it can be found in the queue-4.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable(a)vger.kernel.org> know about it.
>From d0f833065221cbfcbadf19fd4102bcfa9330006a Mon Sep 17 00:00:00 2001
From: Takashi Iwai <tiwai(a)suse.de>
Date: Fri, 9 Mar 2018 21:58:28 +0100
Subject: ALSA: seq: Fix possible UAF in snd_seq_check_queue()
From: Takashi Iwai <tiwai(a)suse.de>
commit d0f833065221cbfcbadf19fd4102bcfa9330006a upstream.
Although we've covered the races between concurrent write() and
ioctl() in the previous patch series, there is still a possible UAF in
the following scenario:
A: user client closed B: timer irq
-> snd_seq_release() -> snd_seq_timer_interrupt()
-> snd_seq_free_client() -> snd_seq_check_queue()
-> cell = snd_seq_prioq_cell_peek()
-> snd_seq_prioq_leave()
.... removing all cells
-> snd_seq_pool_done()
.... vfree()
-> snd_seq_compare_tick_time(cell)
... Oops
So the problem is that a cell is peeked and accessed without any
protection until it's retrieved from the queue again via
snd_seq_prioq_cell_out().
This patch tries to address it, also cleans up the code by a slight
refactoring. snd_seq_prioq_cell_out() now receives an extra pointer
argument. When it's non-NULL, the function checks the event timestamp
with the given pointer. The caller needs to pass the right reference
either to snd_seq_tick or snd_seq_realtime depending on the event
timestamp type.
A good news is that the above change allows us to remove the
snd_seq_prioq_cell_peek(), too, thus the patch actually reduces the
code size.
Reviewed-by: Nicolai Stange <nstange(a)suse.de>
Cc: <stable(a)vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai(a)suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
---
sound/core/seq/seq_prioq.c | 28 ++++++++++++++--------------
sound/core/seq/seq_prioq.h | 6 ++----
sound/core/seq/seq_queue.c | 28 +++++++++-------------------
3 files changed, 25 insertions(+), 37 deletions(-)
--- a/sound/core/seq/seq_prioq.c
+++ b/sound/core/seq/seq_prioq.c
@@ -87,7 +87,7 @@ void snd_seq_prioq_delete(struct snd_seq
if (f->cells > 0) {
/* drain prioQ */
while (f->cells > 0)
- snd_seq_cell_free(snd_seq_prioq_cell_out(f));
+ snd_seq_cell_free(snd_seq_prioq_cell_out(f, NULL));
}
kfree(f);
@@ -214,8 +214,18 @@ int snd_seq_prioq_cell_in(struct snd_seq
return 0;
}
+/* return 1 if the current time >= event timestamp */
+static int event_is_ready(struct snd_seq_event *ev, void *current_time)
+{
+ if ((ev->flags & SNDRV_SEQ_TIME_STAMP_MASK) == SNDRV_SEQ_TIME_STAMP_TICK)
+ return snd_seq_compare_tick_time(current_time, &ev->time.tick);
+ else
+ return snd_seq_compare_real_time(current_time, &ev->time.time);
+}
+
/* dequeue cell from prioq */
-struct snd_seq_event_cell *snd_seq_prioq_cell_out(struct snd_seq_prioq *f)
+struct snd_seq_event_cell *snd_seq_prioq_cell_out(struct snd_seq_prioq *f,
+ void *current_time)
{
struct snd_seq_event_cell *cell;
unsigned long flags;
@@ -227,6 +237,8 @@ struct snd_seq_event_cell *snd_seq_prioq
spin_lock_irqsave(&f->lock, flags);
cell = f->head;
+ if (cell && current_time && !event_is_ready(&cell->event, current_time))
+ cell = NULL;
if (cell) {
f->head = cell->next;
@@ -252,18 +264,6 @@ int snd_seq_prioq_avail(struct snd_seq_p
return f->cells;
}
-
-/* peek at cell at the head of the prioq */
-struct snd_seq_event_cell *snd_seq_prioq_cell_peek(struct snd_seq_prioq * f)
-{
- if (f == NULL) {
- pr_debug("ALSA: seq: snd_seq_prioq_cell_in() called with NULL prioq\n");
- return NULL;
- }
- return f->head;
-}
-
-
static inline int prioq_match(struct snd_seq_event_cell *cell,
int client, int timestamp)
{
--- a/sound/core/seq/seq_prioq.h
+++ b/sound/core/seq/seq_prioq.h
@@ -44,14 +44,12 @@ void snd_seq_prioq_delete(struct snd_seq
int snd_seq_prioq_cell_in(struct snd_seq_prioq *f, struct snd_seq_event_cell *cell);
/* dequeue cell from prioq */
-struct snd_seq_event_cell *snd_seq_prioq_cell_out(struct snd_seq_prioq *f);
+struct snd_seq_event_cell *snd_seq_prioq_cell_out(struct snd_seq_prioq *f,
+ void *current_time);
/* return number of events available in prioq */
int snd_seq_prioq_avail(struct snd_seq_prioq *f);
-/* peek at cell at the head of the prioq */
-struct snd_seq_event_cell *snd_seq_prioq_cell_peek(struct snd_seq_prioq *f);
-
/* client left queue */
void snd_seq_prioq_leave(struct snd_seq_prioq *f, int client, int timestamp);
--- a/sound/core/seq/seq_queue.c
+++ b/sound/core/seq/seq_queue.c
@@ -277,30 +277,20 @@ void snd_seq_check_queue(struct snd_seq_
__again:
/* Process tick queue... */
- while ((cell = snd_seq_prioq_cell_peek(q->tickq)) != NULL) {
- if (snd_seq_compare_tick_time(&q->timer->tick.cur_tick,
- &cell->event.time.tick)) {
- cell = snd_seq_prioq_cell_out(q->tickq);
- if (cell)
- snd_seq_dispatch_event(cell, atomic, hop);
- } else {
- /* event remains in the queue */
+ for (;;) {
+ cell = snd_seq_prioq_cell_out(q->tickq,
+ &q->timer->tick.cur_tick);
+ if (!cell)
break;
- }
+ snd_seq_dispatch_event(cell, atomic, hop);
}
-
/* Process time queue... */
- while ((cell = snd_seq_prioq_cell_peek(q->timeq)) != NULL) {
- if (snd_seq_compare_real_time(&q->timer->cur_time,
- &cell->event.time.time)) {
- cell = snd_seq_prioq_cell_out(q->timeq);
- if (cell)
- snd_seq_dispatch_event(cell, atomic, hop);
- } else {
- /* event remains in the queue */
+ for (;;) {
+ cell = snd_seq_prioq_cell_out(q->timeq, &q->timer->cur_time);
+ if (!cell)
break;
- }
+ snd_seq_dispatch_event(cell, atomic, hop);
}
/* free lock */
Patches currently in stable-queue which might be from tiwai(a)suse.de are
queue-4.4/alsa-firewire-digi00x-handle-all-midi-messages-on-streaming-packets.patch
queue-4.4/alsa-pcm-fix-uaf-in-snd_pcm_oss_get_formats.patch
queue-4.4/alsa-seq-fix-possible-uaf-in-snd_seq_check_queue.patch
queue-4.4/alsa-hda-revert-power_save-option-default-value.patch
queue-4.4/alsa-seq-clear-client-entry-before-deleting-else-at-closing.patch
This is a note to let you know that I've just added the patch titled
drm/amdgpu/dce: Don't turn off DP sink when disconnected
to the 4.4-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=sum…
The filename of the patch is:
drm-amdgpu-dce-don-t-turn-off-dp-sink-when-disconnected.patch
and it can be found in the queue-4.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable(a)vger.kernel.org> know about it.
>From 7d617264eb22b18d979eac6e85877a141253034e Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Michel=20D=C3=A4nzer?= <michel.daenzer(a)amd.com>
Date: Fri, 9 Mar 2018 18:26:18 +0100
Subject: drm/amdgpu/dce: Don't turn off DP sink when disconnected
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
From: Michel Dänzer <michel.daenzer(a)amd.com>
commit 7d617264eb22b18d979eac6e85877a141253034e upstream.
Turning off the sink in this case causes various issues, because
userspace expects it to stay on until it turns it off explicitly.
Instead, turn the sink off and back on when a display is connected
again. This dance seems necessary for link training to work correctly.
Bugzilla: https://bugs.freedesktop.org/105308
Cc: stable(a)vger.kernel.org
Reviewed-by: Alex Deucher <alexander.deucher(a)amd.com>
Signed-off-by: Michel Dänzer <michel.daenzer(a)amd.com>
Signed-off-by: Alex Deucher <alexander.deucher(a)amd.com>
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
---
drivers/gpu/drm/amd/amdgpu/amdgpu_connectors.c | 29 +++++++++----------------
1 file changed, 11 insertions(+), 18 deletions(-)
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_connectors.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_connectors.c
@@ -69,25 +69,18 @@ void amdgpu_connector_hotplug(struct drm
/* don't do anything if sink is not display port, i.e.,
* passive dp->(dvi|hdmi) adaptor
*/
- if (dig_connector->dp_sink_type == CONNECTOR_OBJECT_ID_DISPLAYPORT) {
- int saved_dpms = connector->dpms;
- /* Only turn off the display if it's physically disconnected */
- if (!amdgpu_display_hpd_sense(adev, amdgpu_connector->hpd.hpd)) {
- drm_helper_connector_dpms(connector, DRM_MODE_DPMS_OFF);
- } else if (amdgpu_atombios_dp_needs_link_train(amdgpu_connector)) {
- /* Don't try to start link training before we
- * have the dpcd */
- if (amdgpu_atombios_dp_get_dpcd(amdgpu_connector))
- return;
+ if (dig_connector->dp_sink_type == CONNECTOR_OBJECT_ID_DISPLAYPORT &&
+ amdgpu_display_hpd_sense(adev, amdgpu_connector->hpd.hpd) &&
+ amdgpu_atombios_dp_needs_link_train(amdgpu_connector)) {
+ /* Don't start link training before we have the DPCD */
+ if (amdgpu_atombios_dp_get_dpcd(amdgpu_connector))
+ return;
- /* set it to OFF so that drm_helper_connector_dpms()
- * won't return immediately since the current state
- * is ON at this point.
- */
- connector->dpms = DRM_MODE_DPMS_OFF;
- drm_helper_connector_dpms(connector, DRM_MODE_DPMS_ON);
- }
- connector->dpms = saved_dpms;
+ /* Turn the connector off and back on immediately, which
+ * will trigger link training
+ */
+ drm_helper_connector_dpms(connector, DRM_MODE_DPMS_OFF);
+ drm_helper_connector_dpms(connector, DRM_MODE_DPMS_ON);
}
}
}
Patches currently in stable-queue which might be from michel.daenzer(a)amd.com are
queue-4.4/drm-amdgpu-fail-fb-creation-from-imported-dma-bufs.-v2.patch
queue-4.4/drm-amdgpu-dce-don-t-turn-off-dp-sink-when-disconnected.patch
queue-4.4/drm-radeon-fail-fb-creation-from-imported-dma-bufs.patch
This is a note to let you know that I've just added the patch titled
ALSA: seq: Clear client entry before deleting else at closing
to the 4.4-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=sum…
The filename of the patch is:
alsa-seq-clear-client-entry-before-deleting-else-at-closing.patch
and it can be found in the queue-4.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable(a)vger.kernel.org> know about it.
>From a2ff19f7b70118ced291a28d5313469914de451b Mon Sep 17 00:00:00 2001
From: Takashi Iwai <tiwai(a)suse.de>
Date: Fri, 9 Mar 2018 22:23:31 +0100
Subject: ALSA: seq: Clear client entry before deleting else at closing
From: Takashi Iwai <tiwai(a)suse.de>
commit a2ff19f7b70118ced291a28d5313469914de451b upstream.
When releasing a client, we need to clear the clienttab[] entry at
first, then call snd_seq_queue_client_leave(). Otherwise, the
in-flight cell in the queue might be picked up by the timer interrupt
via snd_seq_check_queue() before calling snd_seq_queue_client_leave(),
and it's delivered to another queue while the client is clearing
queues. This may eventually result in an uncleared cell remaining in
a queue, and the later snd_seq_pool_delete() may need to wait for a
long time until the event gets really processed.
By moving the clienttab[] clearance at the beginning of release, any
event delivery of a cell belonging to this client will fail at a later
point, since snd_seq_client_ptr() returns NULL. Thus the cell that
was picked up by the timer interrupt will be returned immediately
without further delivery, and the long stall of snd_seq_delete_pool()
can be avoided, too.
Cc: <stable(a)vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai(a)suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
---
sound/core/seq/seq_clientmgr.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
--- a/sound/core/seq/seq_clientmgr.c
+++ b/sound/core/seq/seq_clientmgr.c
@@ -270,12 +270,12 @@ static int seq_free_client1(struct snd_s
if (!client)
return 0;
- snd_seq_delete_all_ports(client);
- snd_seq_queue_client_leave(client->number);
spin_lock_irqsave(&clients_lock, flags);
clienttablock[client->number] = 1;
clienttab[client->number] = NULL;
spin_unlock_irqrestore(&clients_lock, flags);
+ snd_seq_delete_all_ports(client);
+ snd_seq_queue_client_leave(client->number);
snd_use_lock_sync(&client->use_lock);
snd_seq_queue_client_termination(client->number);
if (client->pool)
Patches currently in stable-queue which might be from tiwai(a)suse.de are
queue-4.4/alsa-firewire-digi00x-handle-all-midi-messages-on-streaming-packets.patch
queue-4.4/alsa-pcm-fix-uaf-in-snd_pcm_oss_get_formats.patch
queue-4.4/alsa-seq-fix-possible-uaf-in-snd_seq_check_queue.patch
queue-4.4/alsa-hda-revert-power_save-option-default-value.patch
queue-4.4/alsa-seq-clear-client-entry-before-deleting-else-at-closing.patch
This is a note to let you know that I've just added the patch titled
ALSA: pcm: Fix UAF in snd_pcm_oss_get_formats()
to the 4.4-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=sum…
The filename of the patch is:
alsa-pcm-fix-uaf-in-snd_pcm_oss_get_formats.patch
and it can be found in the queue-4.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable(a)vger.kernel.org> know about it.
>From 01c0b4265cc16bc1f43f475c5944c55c10d5768f Mon Sep 17 00:00:00 2001
From: Takashi Iwai <tiwai(a)suse.de>
Date: Sat, 10 Mar 2018 23:04:23 +0100
Subject: ALSA: pcm: Fix UAF in snd_pcm_oss_get_formats()
From: Takashi Iwai <tiwai(a)suse.de>
commit 01c0b4265cc16bc1f43f475c5944c55c10d5768f upstream.
snd_pcm_oss_get_formats() has an obvious use-after-free around
snd_mask_test() calls, as spotted by syzbot. The passed format_mask
argument is a pointer to the hw_params object that is freed before the
loop. What a surprise that it has been present since the original
code of decades ago...
Reported-by: syzbot+4090700a4f13fccaf648(a)syzkaller.appspotmail.com
Cc: <stable(a)vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai(a)suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
---
sound/core/oss/pcm_oss.c | 10 ++++++----
1 file changed, 6 insertions(+), 4 deletions(-)
--- a/sound/core/oss/pcm_oss.c
+++ b/sound/core/oss/pcm_oss.c
@@ -1814,10 +1814,9 @@ static int snd_pcm_oss_get_formats(struc
return -ENOMEM;
_snd_pcm_hw_params_any(params);
err = snd_pcm_hw_refine(substream, params);
- format_mask = *hw_param_mask(params, SNDRV_PCM_HW_PARAM_FORMAT);
- kfree(params);
if (err < 0)
- return err;
+ goto error;
+ format_mask = hw_param_mask_c(params, SNDRV_PCM_HW_PARAM_FORMAT);
for (fmt = 0; fmt < 32; ++fmt) {
if (snd_mask_test(&format_mask, fmt)) {
int f = snd_pcm_oss_format_to(fmt);
@@ -1825,7 +1824,10 @@ static int snd_pcm_oss_get_formats(struc
formats |= f;
}
}
- return formats;
+
+ error:
+ kfree(params);
+ return err < 0 ? err : formats;
}
static int snd_pcm_oss_set_format(struct snd_pcm_oss_file *pcm_oss_file, int format)
Patches currently in stable-queue which might be from tiwai(a)suse.de are
queue-4.4/alsa-firewire-digi00x-handle-all-midi-messages-on-streaming-packets.patch
queue-4.4/alsa-pcm-fix-uaf-in-snd_pcm_oss_get_formats.patch
queue-4.4/alsa-seq-fix-possible-uaf-in-snd_seq_check_queue.patch
queue-4.4/alsa-hda-revert-power_save-option-default-value.patch
queue-4.4/alsa-seq-clear-client-entry-before-deleting-else-at-closing.patch