IF YOU WOULD LIKE TO GET AN ACCOUNT, please write an
email to Administrator. User accounts are meant only to access repo
and report issues and/or generate pull requests.
This is a purpose-specific Git hosting for
BaseALT
projects. Thank you for your understanding!
Только зарегистрированные пользователи имеют доступ к сервису!
Для получения аккаунта, обратитесь к администратору.
commit 11933cf1d91d57da9e5c53822a540bbdc2656c16 upstream.
The propagate_mnt() function handles mount propagation when creating
mounts and propagates the source mount tree @source_mnt to all
applicable nodes of the destination propagation mount tree headed by
@dest_mnt.
Unfortunately it contains a bug where it fails to terminate at peers of
@source_mnt when looking up copies of the source mount that become
masters for copies of the source mount tree mounted on top of slaves in
the destination propagation tree causing a NULL dereference.
Once the mechanics of the bug are understood it's easy to trigger.
Because of unprivileged user namespaces it is available to unprivileged
users.
While fixing this bug we've gotten confused multiple times due to
unclear terminology or missing concepts. So let's start this with some
clarifications:
* The terms "master" or "peer" denote a shared mount. A shared mount
belongs to a peer group.
* A peer group is a set of shared mounts that propagate to each other.
They are identified by a peer group id. The peer group id is available
in @shared_mnt->mnt_group_id.
Shared mounts within the same peer group have the same peer group id.
The peers in a peer group can be reached via @shared_mnt->mnt_share.
* The terms "slave mount" or "dependent mount" denote a mount that
receives propagation from a peer in a peer group. IOW, shared mounts
may have slave mounts and slave mounts have shared mounts as their
master. Slave mounts of a given peer in a peer group are listed on
that peers slave list available at @shared_mnt->mnt_slave_list.
* The term "master mount" denotes a mount in a peer group. IOW, it
denotes a shared mount or a peer mount in a peer group. The term
"master mount" - or "master" for short - is mostly used when talking
in the context of slave mounts that receive propagation from a master
mount. A master mount of a slave identifies the closest peer group a
slave mount receives propagation from. The master mount of a slave can
be identified via @slave_mount->mnt_master. Different slaves may point
to different masters in the same peer group.
* Multiple peers in a peer group can have non-empty ->mnt_slave_lists.
Non-empty ->mnt_slave_lists of peers don't intersect. Consequently, to
ensure all slave mounts of a peer group are visited the
->mnt_slave_lists of all peers in a peer group have to be walked.
* Slave mounts point to a peer in the closest peer group they receive
propagation from via @slave_mnt->mnt_master (see above). Together with
these peers they form a propagation group (see below). The closest
peer group can thus be identified through the peer group id
@slave_mnt->mnt_master->mnt_group_id of the peer/master that a slave
mount receives propagation from.
* A shared-slave mount is a slave mount to a peer group pg1 while also
a peer in another peer group pg2. IOW, a peer group may receive
propagation from another peer group.
If a peer group pg1 is a slave to another peer group pg2 then all
peers in peer group pg1 point to the same peer in peer group pg2 via
->mnt_master. IOW, all peers in peer group pg1 appear on the same
->mnt_slave_list. IOW, they cannot be slaves to different peer groups.
* A pure slave mount is a slave mount that is a slave to a peer group
but is not a peer in another peer group.
* A propagation group denotes the set of mounts consisting of a single
peer group pg1 and all slave mounts and shared-slave mounts that point
to a peer in that peer group via ->mnt_master. IOW, all slave mounts
such that @slave_mnt->mnt_master->mnt_group_id is equal to
@shared_mnt->mnt_group_id.
The concept of a propagation group makes it easier to talk about a
single propagation level in a propagation tree.
For example, in propagate_mnt() the immediate peers of @dest_mnt and
all slaves of @dest_mnt's peer group form a propagation group propg1.
So a shared-slave mount that is a slave in propg1 and that is a peer
in another peer group pg2 forms another propagation group propg2
together with all slaves that point to that shared-slave mount in
their ->mnt_master.
* A propagation tree refers to all mounts that receive propagation
starting from a specific shared mount.
For example, for propagate_mnt() @dest_mnt is the start of a
propagation tree. The propagation tree ecompasses all mounts that
receive propagation from @dest_mnt's peer group down to the leafs.
With that out of the way let's get to the actual algorithm.
We know that @dest_mnt is guaranteed to be a pure shared mount or a
shared-slave mount. This is guaranteed by a check in
attach_recursive_mnt(). So propagate_mnt() will first propagate the
source mount tree to all peers in @dest_mnt's peer group:
for (n = next_peer(dest_mnt); n != dest_mnt; n = next_peer(n)) {
ret = propagate_one(n);
if (ret)
goto out;
}
Notice, that the peer propagation loop of propagate_mnt() doesn't
propagate @dest_mnt itself. @dest_mnt is mounted directly in
attach_recursive_mnt() after we propagated to the destination
propagation tree.
The mount that will be mounted on top of @dest_mnt is @source_mnt. This
copy was created earlier even before we entered attach_recursive_mnt()
and doesn't concern us a lot here.
It's just important to notice that when propagate_mnt() is called
@source_mnt will not yet have been mounted on top of @dest_mnt. Thus,
@source_mnt->mnt_parent will either still point to @source_mnt or - in
the case @source_mnt is moved and thus already attached - still to its
former parent.
For each peer @m in @dest_mnt's peer group propagate_one() will create a
new copy of the source mount tree and mount that copy @child on @m such
that @child->mnt_parent points to @m after propagate_one() returns.
propagate_one() will stash the last destination propagation node @m in
@last_dest and the last copy it created for the source mount tree in
@last_source.
Hence, if we call into propagate_one() again for the next destination
propagation node @m, @last_dest will point to the previous destination
propagation node and @last_source will point to the previous copy of the
source mount tree and mounted on @last_dest.
Each new copy of the source mount tree is created from the previous copy
of the source mount tree. This will become important later.
The peer loop in propagate_mnt() is straightforward. We iterate through
the peers copying and updating @last_source and @last_dest as we go
through them and mount each copy of the source mount tree @child on a
peer @m in @dest_mnt's peer group.
After propagate_mnt() handled the peers in @dest_mnt's peer group
propagate_mnt() will propagate the source mount tree down the
propagation tree that @dest_mnt's peer group propagates to:
for (m = next_group(dest_mnt, dest_mnt); m;
m = next_group(m, dest_mnt)) {
/* everything in that slave group */
n = m;
do {
ret = propagate_one(n);
if (ret)
goto out;
n = next_peer(n);
} while (n != m);
}
The next_group() helper will recursively walk the destination
propagation tree, descending into each propagation group of the
propagation tree.
The important part is that it takes care to propagate the source mount
tree to all peers in the peer group of a propagation group before it
propagates to the slaves to those peers in the propagation group. IOW,
it creates and mounts copies of the source mount tree that become
masters before it creates and mounts copies of the source mount tree
that become slaves to these masters.
It is important to remember that propagating the source mount tree to
each mount @m in the destination propagation tree simply means that we
create and mount new copies @child of the source mount tree on @m such
that @child->mnt_parent points to @m.
Since we know that each node @m in the destination propagation tree
headed by @dest_mnt's peer group will be overmounted with a copy of the
source mount tree and since we know that the propagation properties of
each copy of the source mount tree we create and mount at @m will mostly
mirror the propagation properties of @m. We can use that information to
create and mount the copies of the source mount tree that become masters
before their slaves.
The easy case is always when @m and @last_dest are peers in a peer group
of a given propagation group. In that case we know that we can simply
copy @last_source without having to figure out what the master for the
new copy @child of the source mount tree needs to be as we've done that
in a previous call to propagate_one().
The hard case is when we're dealing with a slave mount or a shared-slave
mount @m in a destination propagation group that we need to create and
mount a copy of the source mount tree on.
For each propagation group in the destination propagation tree we
propagate the source mount tree to we want to make sure that the copies
@child of the source mount tree we create and mount on slaves @m pick an
ealier copy of the source mount tree that we mounted on a master @m of
the destination propagation group as their master. This is a mouthful
but as far as we can tell that's the core of it all.
But, if we keep track of the masters in the destination propagation tree
@m we can use the information to find the correct master for each copy
of the source mount tree we create and mount at the slaves in the
destination propagation tree @m.
Let's walk through the base case as that's still fairly easy to grasp.
If we're dealing with the first slave in the propagation group that
@dest_mnt is in then we don't yet have marked any masters in the
destination propagation tree.
We know the master for the first slave to @dest_mnt's peer group is
simple @dest_mnt. So we expect this algorithm to yield a copy of the
source mount tree that was mounted on a peer in @dest_mnt's peer group
as the master for the copy of the source mount tree we want to mount at
the first slave @m:
for (n = m; ; n = p) {
p = n->mnt_master;
if (p == dest_master || IS_MNT_MARKED(p))
break;
}
For the first slave we walk the destination propagation tree all the way
up to a peer in @dest_mnt's peer group. IOW, the propagation hierarchy
can be walked by walking up the @mnt->mnt_master hierarchy of the
destination propagation tree @m. We will ultimately find a peer in
@dest_mnt's peer group and thus ultimately @dest_mnt->mnt_master.
Btw, here the assumption we listed at the beginning becomes important.
Namely, that peers in a peer group pg1 that are slaves in another peer
group pg2 appear on the same ->mnt_slave_list. IOW, all slaves who are
peers in peer group pg1 point to the same peer in peer group pg2 via
their ->mnt_master. Otherwise the termination condition in the code
above would be wrong and next_group() would be broken too.
So the first iteration sets:
n = m;
p = n->mnt_master;
such that @p now points to a peer or @dest_mnt itself. We walk up one
more level since we don't have any marked mounts. So we end up with:
n = dest_mnt;
p = dest_mnt->mnt_master;
If @dest_mnt's peer group is not slave to another peer group then @p is
now NULL. If @dest_mnt's peer group is a slave to another peer group
then @p now points to @dest_mnt->mnt_master points which is a master
outside the propagation tree we're dealing with.
Now we need to figure out the master for the copy of the source mount
tree we're about to create and mount on the first slave of @dest_mnt's
peer group:
do {
struct mount *parent = last_source->mnt_parent;
if (last_source == first_source)
break;
done = parent->mnt_master == p;
if (done && peers(n, parent))
break;
last_source = last_source->mnt_master;
} while (!done);
We know that @last_source->mnt_parent points to @last_dest and
@last_dest is the last peer in @dest_mnt's peer group we propagated to
in the peer loop in propagate_mnt().
Consequently, @last_source is the last copy we created and mount on that
last peer in @dest_mnt's peer group. So @last_source is the master we
want to pick.
We know that @last_source->mnt_parent->mnt_master points to
@last_dest->mnt_master. We also know that @last_dest->mnt_master is
either NULL or points to a master outside of the destination propagation
tree and so does @p. Hence:
done = parent->mnt_master == p;
is trivially true in the base condition.
We also know that for the first slave mount of @dest_mnt's peer group
that @last_dest either points @dest_mnt itself because it was
initialized to:
last_dest = dest_mnt;
at the beginning of propagate_mnt() or it will point to a peer of
@dest_mnt in its peer group. In both cases it is guaranteed that on the
first iteration @n and @parent are peers (Please note the check for
peers here as that's important.):
if (done && peers(n, parent))
break;
So, as we expected, we select @last_source, which referes to the last
copy of the source mount tree we mounted on the last peer in @dest_mnt's
peer group, as the master of the first slave in @dest_mnt's peer group.
The rest is taken care of by clone_mnt(last_source, ...). We'll skip
over that part otherwise this becomes a blogpost.
At the end of propagate_mnt() we now mark @m->mnt_master as the first
master in the destination propagation tree that is distinct from
@dest_mnt->mnt_master. IOW, we mark @dest_mnt itself as a master.
By marking @dest_mnt or one of it's peers we are able to easily find it
again when we later lookup masters for other copies of the source mount
tree we mount copies of the source mount tree on slaves @m to
@dest_mnt's peer group. This, in turn allows us to find the master we
selected for the copies of the source mount tree we mounted on master in
the destination propagation tree again.
The important part is to realize that the code makes use of the fact
that the last copy of the source mount tree stashed in @last_source was
mounted on top of the previous destination propagation node @last_dest.
What this means is that @last_source allows us to walk the destination
propagation hierarchy the same way each destination propagation node @m
does.
If we take @last_source, which is the copy of @source_mnt we have
mounted on @last_dest in the previous iteration of propagate_one(), then
we know @last_source->mnt_parent points to @last_dest but we also know
that as we walk through the destination propagation tree that
@last_source->mnt_master will point to an earlier copy of the source
mount tree we mounted one an earlier destination propagation node @m.
IOW, @last_source->mnt_parent will be our hook into the destination
propagation tree and each consecutive @last_source->mnt_master will lead
us to an earlier propagation node @m via
@last_source->mnt_master->mnt_parent.
Hence, by walking up @last_source->mnt_master, each of which is mounted
on a node that is a master @m in the destination propagation tree we can
also walk up the destination propagation hierarchy.
So, for each new destination propagation node @m we use the previous
copy of @last_source and the fact it's mounted on the previous
propagation node @last_dest via @last_source->mnt_master->mnt_parent to
determine what the master of the new copy of @last_source needs to be.
The goal is to find the _closest_ master that the new copy of the source
mount tree we are about to create and mount on a slave @m in the
destination propagation tree needs to pick. IOW, we want to find a
suitable master in the propagation group.
As the propagation structure of the source mount propagation tree we
create mirrors the propagation structure of the destination propagation
tree we can find @m's closest master - i.e., a marked master - which is
a peer in the closest peer group that @m receives propagation from. We
store that closest master of @m in @p as before and record the slave to
that master in @n
We then search for this master @p via @last_source by walking up the
master hierarchy starting from the last copy of the source mount tree
stored in @last_source that we created and mounted on the previous
destination propagation node @m.
We will try to find the master by walking @last_source->mnt_master and
by comparing @last_source->mnt_master->mnt_parent->mnt_master to @p. If
we find @p then we can figure out what earlier copy of the source mount
tree needs to be the master for the new copy of the source mount tree
we're about to create and mount at the current destination propagation
node @m.
If @last_source->mnt_master->mnt_parent and @n are peers then we know
that the closest master they receive propagation from is
@last_source->mnt_master->mnt_parent->mnt_master. If not then the
closest immediate peer group that they receive propagation from must be
one level higher up.
This builds on the earlier clarification at the beginning that all peers
in a peer group which are slaves of other peer groups all point to the
same ->mnt_master, i.e., appear on the same ->mnt_slave_list, of the
closest peer group that they receive propagation from.
However, terminating the walk has corner cases.
If the closest marked master for a given destination node @m cannot be
found by walking up the master hierarchy via @last_source->mnt_master
then we need to terminate the walk when we encounter @source_mnt again.
This isn't an arbitrary termination. It simply means that the new copy
of the source mount tree we're about to create has a copy of the source
mount tree we created and mounted on a peer in @dest_mnt's peer group as
its master. IOW, @source_mnt is the peer in the closest peer group that
the new copy of the source mount tree receives propagation from.
We absolutely have to stop @source_mnt because @last_source->mnt_master
either points outside the propagation hierarchy we're dealing with or it
is NULL because @source_mnt isn't a shared-slave.
So continuing the walk past @source_mnt would cause a NULL dereference
via @last_source->mnt_master->mnt_parent. And so we have to stop the
walk when we encounter @source_mnt again.
One scenario where this can happen is when we first handled a series of
slaves of @dest_mnt's peer group and then encounter peers in a new peer
group that is a slave to @dest_mnt's peer group. We handle them and then
we encounter another slave mount to @dest_mnt that is a pure slave to
@dest_mnt's peer group. That pure slave will have a peer in @dest_mnt's
peer group as its master. Consequently, the new copy of the source mount
tree will need to have @source_mnt as it's master. So we walk the
propagation hierarchy all the way up to @source_mnt based on
@last_source->mnt_master.
So terminate on @source_mnt, easy peasy. Except, that the check misses
something that the rest of the algorithm already handles.
If @dest_mnt has peers in it's peer group the peer loop in
propagate_mnt():
for (n = next_peer(dest_mnt); n != dest_mnt; n = next_peer(n)) {
ret = propagate_one(n);
if (ret)
goto out;
}
will consecutively update @last_source with each previous copy of the
source mount tree we created and mounted at the previous peer in
@dest_mnt's peer group. So after that loop terminates @last_source will
point to whatever copy of the source mount tree was created and mounted
on the last peer in @dest_mnt's peer group.
Furthermore, if there is even a single additional peer in @dest_mnt's
peer group then @last_source will __not__ point to @source_mnt anymore.
Because, as we mentioned above, @dest_mnt isn't even handled in this
loop but directly in attach_recursive_mnt(). So it can't even accidently
come last in that peer loop.
So the first time we handle a slave mount @m of @dest_mnt's peer group
the copy of the source mount tree we create will make the __last copy of
the source mount tree we created and mounted on the last peer in
@dest_mnt's peer group the master of the new copy of the source mount
tree we create and mount on the first slave of @dest_mnt's peer group__.
But this means that the termination condition that checks for
@source_mnt is wrong. The @source_mnt cannot be found anymore by
propagate_one(). Instead it will find the last copy of the source mount
tree we created and mounted for the last peer of @dest_mnt's peer group
again. And that is a peer of @source_mnt not @source_mnt itself.
IOW, we fail to terminate the loop correctly and ultimately dereference
@last_source->mnt_master->mnt_parent. When @source_mnt's peer group
isn't slave to another peer group then @last_source->mnt_master is NULL
causing the splat below.
For example, assume @dest_mnt is a pure shared mount and has three peers
in its peer group:
===================================================================================
mount-id mount-parent-id peer-group-id
===================================================================================
(@dest_mnt) mnt_master[216] 309 297 shared:216
\
(@source_mnt) mnt_master[218]: 609 609 shared:218
(1) mnt_master[216]: 607 605 shared:216
\
(P1) mnt_master[218]: 624 607 shared:218
(2) mnt_master[216]: 576 574 shared:216
\
(P2) mnt_master[218]: 625 576 shared:218
(3) mnt_master[216]: 545 543 shared:216
\
(P3) mnt_master[218]: 626 545 shared:218
After this sequence has been processed @last_source will point to (P3),
the copy generated for the third peer in @dest_mnt's peer group we
handled. So the copy of the source mount tree (P4) we create and mount
on the first slave of @dest_mnt's peer group:
===================================================================================
mount-id mount-parent-id peer-group-id
===================================================================================
mnt_master[216] 309 297 shared:216
/
/
(S0) mnt_slave 483 481 master:216
\
\ (P3) mnt_master[218] 626 545 shared:218
\ /
\/
(P4) mnt_slave 627 483 master:218
will pick the last copy of the source mount tree (P3) as master, not (S0).
When walking the propagation hierarchy via @last_source's master
hierarchy we encounter (P3) but not (S0), i.e., @source_mnt.
We can fix this in multiple ways:
(1) By setting @last_source to @source_mnt after we processed the peers
in @dest_mnt's peer group right after the peer loop in
propagate_mnt().
(2) By changing the termination condition that relies on finding exactly
@source_mnt to finding a peer of @source_mnt.
(3) By only moving @last_source when we actually venture into a new peer
group or some clever variant thereof.
The first two options are minimally invasive and what we want as a fix.
The third option is more intrusive but something we'd like to explore in
the near future.
This passes all LTP tests and specifically the mount propagation
testsuite part of it. It also holds up against all known reproducers of
this issues.
Final words.
First, this is a clever but __worringly__ underdocumented algorithm.
There isn't a single detailed comment to be found in next_group(),
propagate_one() or anywhere else in that file for that matter. This has
been a giant pain to understand and work through and a bug like this is
insanely difficult to fix without a detailed understanding of what's
happening. Let's not talk about the amount of time that was sunk into
fixing this.
Second, all the cool kids with access to
unshare --mount --user --map-root --propagation=unchanged
are going to have a lot of fun. IOW, triggerable by unprivileged users
while namespace_lock() lock is held.
[ 115.848393] BUG: kernel NULL pointer dereference, address: 0000000000000010
[ 115.848967] #PF: supervisor read access in kernel mode
[ 115.849386] #PF: error_code(0x0000) - not-present page
[ 115.849803] PGD 0 P4D 0
[ 115.850012] Oops: 0000 [#1] PREEMPT SMP PTI
[ 115.850354] CPU: 0 PID: 15591 Comm: mount Not tainted 6.1.0-rc7 #3
[ 115.850851] Hardware name: innotek GmbH VirtualBox/VirtualBox, BIOS
VirtualBox 12/01/2006
[ 115.851510] RIP: 0010:propagate_one.part.0+0x7f/0x1a0
[ 115.851924] Code: 75 eb 4c 8b 05 c2 25 37 02 4c 89 ca 48 8b 4a 10
49 39 d0 74 1e 48 3b 81 e0 00 00 00 74 26 48 8b 92 e0 00 00 00 be 01
00 00 00 <48> 8b 4a 10 49 39 d0 75 e2 40 84 f6 74 38 4c 89 05 84 25 37
02 4d
[ 115.853441] RSP: 0018:ffffb8d5443d7d50 EFLAGS: 00010282
[ 115.853865] RAX: ffff8e4d87c41c80 RBX: ffff8e4d88ded780 RCX: ffff8e4da4333a00
[ 115.854458] RDX: 0000000000000000 RSI: 0000000000000001 RDI: ffff8e4d88ded780
[ 115.855044] RBP: ffff8e4d88ded780 R08: ffff8e4da4338000 R09: ffff8e4da43388c0
[ 115.855693] R10: 0000000000000002 R11: ffffb8d540158000 R12: ffffb8d5443d7da8
[ 115.856304] R13: ffff8e4d88ded780 R14: 0000000000000000 R15: 0000000000000000
[ 115.856859] FS: 00007f92c90c9800(0000) GS:ffff8e4dfdc00000(0000)
knlGS:0000000000000000
[ 115.857531] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 115.858006] CR2: 0000000000000010 CR3: 0000000022f4c002 CR4: 00000000000706f0
[ 115.858598] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[ 115.859393] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[ 115.860099] Call Trace:
[ 115.860358] <TASK>
[ 115.860535] propagate_mnt+0x14d/0x190
[ 115.860848] attach_recursive_mnt+0x274/0x3e0
[ 115.861212] path_mount+0x8c8/0xa60
[ 115.861503] __x64_sys_mount+0xf6/0x140
[ 115.861819] do_syscall_64+0x5b/0x80
[ 115.862117] ? do_faccessat+0x123/0x250
[ 115.862435] ? syscall_exit_to_user_mode+0x17/0x40
[ 115.862826] ? do_syscall_64+0x67/0x80
[ 115.863133] ? syscall_exit_to_user_mode+0x17/0x40
[ 115.863527] ? do_syscall_64+0x67/0x80
[ 115.863835] ? do_syscall_64+0x67/0x80
[ 115.864144] ? do_syscall_64+0x67/0x80
[ 115.864452] ? exc_page_fault+0x70/0x170
[ 115.864775] entry_SYSCALL_64_after_hwframe+0x63/0xcd
[ 115.865187] RIP: 0033:0x7f92c92b0ebe
[ 115.865480] Code: 48 8b 0d 75 4f 0c 00 f7 d8 64 89 01 48 83 c8 ff
c3 66 2e 0f 1f 84 00 00 00 00 00 90 f3 0f 1e fa 49 89 ca b8 a5 00 00
00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d 42 4f 0c 00 f7 d8 64 89
01 48
[ 115.866984] RSP: 002b:00007fff000aa728 EFLAGS: 00000246 ORIG_RAX:
00000000000000a5
[ 115.867607] RAX: ffffffffffffffda RBX: 000055a77888d6b0 RCX: 00007f92c92b0ebe
[ 115.868240] RDX: 000055a77888d8e0 RSI: 000055a77888e6e0 RDI: 000055a77888e620
[ 115.868823] RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000001
[ 115.869403] R10: 0000000000001000 R11: 0000000000000246 R12: 000055a77888e620
[ 115.869994] R13: 000055a77888d8e0 R14: 00000000ffffffff R15: 00007f92c93e4076
[ 115.870581] </TASK>
[ 115.870763] Modules linked in: nft_fib_inet nft_fib_ipv4
nft_fib_ipv6 nft_fib nft_reject_inet nf_reject_ipv4 nf_reject_ipv6
nft_reject nft_ct nft_chain_nat nf_nat nf_conntrack nf_defrag_ipv6
nf_defrag_ipv4 ip_set rfkill nf_tables nfnetlink qrtr snd_intel8x0
sunrpc snd_ac97_codec ac97_bus snd_pcm snd_timer intel_rapl_msr
intel_rapl_common snd vboxguest intel_powerclamp video rapl joydev
soundcore i2c_piix4 wmi fuse zram xfs vmwgfx crct10dif_pclmul
crc32_pclmul crc32c_intel polyval_clmulni polyval_generic
drm_ttm_helper ttm e1000 ghash_clmulni_intel serio_raw ata_generic
pata_acpi scsi_dh_rdac scsi_dh_emc scsi_dh_alua dm_multipath
[ 115.875288] CR2: 0000000000000010
[ 115.875641] ---[ end trace 0000000000000000 ]---
[ 115.876135] RIP: 0010:propagate_one.part.0+0x7f/0x1a0
[ 115.876551] Code: 75 eb 4c 8b 05 c2 25 37 02 4c 89 ca 48 8b 4a 10
49 39 d0 74 1e 48 3b 81 e0 00 00 00 74 26 48 8b 92 e0 00 00 00 be 01
00 00 00 <48> 8b 4a 10 49 39 d0 75 e2 40 84 f6 74 38 4c 89 05 84 25 37
02 4d
[ 115.878086] RSP: 0018:ffffb8d5443d7d50 EFLAGS: 00010282
[ 115.878511] RAX: ffff8e4d87c41c80 RBX: ffff8e4d88ded780 RCX: ffff8e4da4333a00
[ 115.879128] RDX: 0000000000000000 RSI: 0000000000000001 RDI: ffff8e4d88ded780
[ 115.879715] RBP: ffff8e4d88ded780 R08: ffff8e4da4338000 R09: ffff8e4da43388c0
[ 115.880359] R10: 0000000000000002 R11: ffffb8d540158000 R12: ffffb8d5443d7da8
[ 115.880962] R13: ffff8e4d88ded780 R14: 0000000000000000 R15: 0000000000000000
[ 115.881548] FS: 00007f92c90c9800(0000) GS:ffff8e4dfdc00000(0000)
knlGS:0000000000000000
[ 115.882234] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 115.882713] CR2: 0000000000000010 CR3: 0000000022f4c002 CR4: 00000000000706f0
[ 115.883314] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[ 115.883966] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Fixes: f2ebb3a921c1 ("smarter propagate_mnt()")
Fixes: 5ec0811d3037 ("propogate_mnt: Handle the first propogated copy being a slave")
Cc: <stable@vger.kernel.org>
Reported-by: Ditang Chen <ditang.c@gmail.com>
Signed-off-by: Seth Forshee (Digital Ocean) <sforshee@kernel.org>
Signed-off-by: Christian Brauner (Microsoft) <brauner@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 456b59e757b0c558df550764a4fd5ae6877e93f8 upstream.
ovl_change_flags() is an open-coded variant of fs/fcntl.c:setfl() and it
got missed by commit 164f4064ca81 ("keep iocb_flags() result cached in
struct file"); the same change applies there.
Reported-by: Pierre Labastie <pierre.labastie@neuf.fr>
Fixes: 164f4064ca81 ("keep iocb_flags() result cached in struct file")
Cc: <stable@vger.kernel.org> # v6.0
Link: https://bugzilla.kernel.org/show_bug.cgi?id=216738
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 5b0db51215e895a361bc63132caa7cca36a53d6a upstream.
There is a wrong case of link() on overlay:
$ mkdir /lower /fuse /merge
$ mount -t fuse /fuse
$ mkdir /fuse/upper /fuse/work
$ mount -t overlay /merge -o lowerdir=/lower,upperdir=/fuse/upper,\
workdir=work
$ touch /merge/file
$ chown bin.bin /merge/file // the file's caller becomes "bin"
$ ln /merge/file /merge/lnkfile
Then we will get an error(EACCES) because fuse daemon checks the link()'s
caller is "bin", it denied this request.
In the changing history of ovl_link(), there are two key commits:
The first is commit bb0d2b8ad296 ("ovl: fix sgid on directory") which
overrides the cred's fsuid/fsgid using the new inode. The new inode's
owner is initialized by inode_init_owner(), and inode->fsuid is
assigned to the current user. So the override fsuid becomes the
current user. We know link() is actually modifying the directory, so
the caller must have the MAY_WRITE permission on the directory. The
current caller may should have this permission. This is acceptable
to use the caller's fsuid.
The second is commit 51f7e52dc943 ("ovl: share inode for hard link")
which removed the inode creation in ovl_link(). This commit move
inode_init_owner() into ovl_create_object(), so the ovl_link() just
give the old inode to ovl_create_or_link(). Then the override fsuid
becomes the old inode's fsuid, neither the caller nor the overlay's
mounter! So this is incorrect.
Fix this bug by using ovl mounter's fsuid/fsgid to do underlying
fs's link().
Link: https://lore.kernel.org/all/20220817102952.xnvesg3a7rbv576x@wittgenstein/T
Link: https://lore.kernel.org/lkml/20220825130552.29587-1-zhangtianci.1997@bytedance.com/t
Signed-off-by: Zhang Tianci <zhangtianci.1997@bytedance.com>
Signed-off-by: Jiachen Zhang <zhangjiachen.jaycee@bytedance.com>
Reviewed-by: Christian Brauner (Microsoft) <brauner@kernel.org>
Fixes: 51f7e52dc943 ("ovl: share inode for hard link")
Cc: <stable@vger.kernel.org> # v4.8
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 9f2b5debc07073e6dfdd774e3594d0224b991927 upstream.
Despite specifying UID and GID in mount command, the specified UID and GID
were not being assigned. This patch fixes this issue.
Link: https://lkml.kernel.org/r/C0264BF5-059C-45CF-B8DA-3A3BD2C803A2@live.com
Signed-off-by: Aditya Garg <gargaditya08@live.com>
Reviewed-by: Viacheslav Dubeyko <slava@dubeyko.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 99b3b837855b987563bcfb397cf9ddd88262814b upstream.
There is a case found when triggering a panic_on_oom, pstore fails to dump
kmsg. Because psz_kmsg_write_record can't get the new buffer.
Handle this by using GFP_ATOMIC to allocate a buffer at lower watermark.
Signed-off-by: Qiujun Huang <hqjagain@gmail.com>
Fixes: 335426c6dcdd ("pstore/zone: Provide way to skip "broken" zone for MTD devices")
Cc: WeiXiong Liao <gmpy.liaowx@gmail.com>
Cc: stable@vger.kernel.org
Signed-off-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/CAJRQjofRCF7wjrYmw3D7zd5QZnwHQq+F8U-mJDJ6NZ4bddYdLA@mail.gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit beca3e311a49cd3c55a056096531737d7afa4361 upstream.
If mem-type is specified in the device tree
it would end up overriding the record_size
field instead of populating mem_type.
As record_size is currently parsed after the
improper assignment with default size 0 it
continued to work as expected regardless of the
value found in the device tree.
Simply changing the target field of the struct
is enough to get mem-type working as expected.
Fixes: 9d843e8fafc7 ("pstore: Add mem_type property DT parsing support")
Cc: stable@vger.kernel.org
Signed-off-by: Luca Stefani <luca@osomprivacy.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20221222131049.286288-1-luca@osomprivacy.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 75333d48f92256a0dec91dbf07835e804fc411c0 ]
Problem caused by source's vfsmount being unmounted but remains
on the delayed unmount list. This happens when nfs42_ssc_open()
return errors.
Fixed by removing nfsd4_interssc_connect(), leave the vfsmount
for the laundromat to unmount when idle time expires.
We don't need to call nfs_do_sb_deactive when nfs42_ssc_open
return errors since the file was not opened so nfs_server->active
was not incremented. Same as in nfsd4_copy, if we fail to
launch nfsd4_do_async_copy thread then there's no need to
call nfs_do_sb_deactive
Reported-by: Xingyuan Mo <hdthky0@gmail.com>
Signed-off-by: Dai Ngo <dai.ngo@oracle.com>
Tested-by: Xingyuan Mo <hdthky0@gmail.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit ecfbd57cf9c5ca225184ae266ce44ae473792132 ]
When PAGE_SIZE is 64K, if read_log_page is called by log_read_rst for
the first time, the size of *buffer would be equal to
DefaultLogPageSize(4K).But for *buffer operations like memcpy,
if the memory area size(n) which being assigned to buffer is larger
than 4K (log->page_size(64K) or bytes(64K-page_off)), it will cause
an out of boundary error.
Call trace:
[...]
kasan_report+0x44/0x130
check_memory_region+0xf8/0x1a0
memcpy+0xc8/0x100
ntfs_read_run_nb+0x20c/0x460
read_log_page+0xd0/0x1f4
log_read_rst+0x110/0x75c
log_replay+0x1e8/0x4aa0
ntfs_loadlog_and_replay+0x290/0x2d0
ntfs_fill_super+0x508/0xec0
get_tree_bdev+0x1fc/0x34c
[...]
Fix this by setting variable r_page to NULL in log_read_rst.
Signed-off-by: Yin Xiujiang <yinxiujiang@kylinos.cn>
Signed-off-by: Konstantin Komarov <almaz.alexandrovich@paragon-software.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 658015167a8432b88f5d032e9d85d8fd50e5bf2c ]
There were two patches which addressed the same bug and added the same
condition:
commit 6db620863f85 ("fs/ntfs3: Validate data run offset")
commit 887bfc546097 ("fs/ntfs3: Fix slab-out-of-bounds read in run_unpack")
Delete one condition.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Konstantin Komarov <almaz.alexandrovich@paragon-software.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 59bfd7a483da36bd202532a3d9ea1f14f3bf3aaf ]
syzbot is reporting too large allocation at ntfs_fill_super() [1], for a
crafted filesystem can contain bogus inode->i_size. Add __GFP_NOWARN in
order to avoid too large allocation warning, than exhausting memory by
using kvmalloc().
Link: https://syzkaller.appspot.com/bug?extid=33f3faaa0c08744f7d40 [1]
Reported-by: syzot <syzbot+33f3faaa0c08744f7d40@syzkaller.appspotmail.com>
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: Konstantin Komarov <almaz.alexandrovich@paragon-software.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 0d0f659bf713662fabed973f9996b8f23c59ca51 ]
syzbot is reporting too large allocation at wnd_init() [1], for a crafted
filesystem can become wnd->nwnd close to UINT_MAX. Add __GFP_NOWARN in
order to avoid too large allocation warning, than exhausting memory by
using kvcalloc().
Link: https://syzkaller.appspot.com/bug?extid=fa4648a5446460b7b963 [1]
Reported-by: syzot <syzbot+fa4648a5446460b7b963@syzkaller.appspotmail.com>
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: Konstantin Komarov <almaz.alexandrovich@paragon-software.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 887bfc546097fbe8071dac13b2fef73b77920899 ]
Syzkaller reports slab-out-of-bounds bug as follows:
==================================================================
BUG: KASAN: slab-out-of-bounds in run_unpack+0x8b7/0x970 fs/ntfs3/run.c:944
Read of size 1 at addr ffff88801bbdff02 by task syz-executor131/3611
[...]
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106
print_address_description mm/kasan/report.c:317 [inline]
print_report.cold+0x2ba/0x719 mm/kasan/report.c:433
kasan_report+0xb1/0x1e0 mm/kasan/report.c:495
run_unpack+0x8b7/0x970 fs/ntfs3/run.c:944
run_unpack_ex+0xb0/0x7c0 fs/ntfs3/run.c:1057
ntfs_read_mft fs/ntfs3/inode.c:368 [inline]
ntfs_iget5+0xc20/0x3280 fs/ntfs3/inode.c:501
ntfs_loadlog_and_replay+0x124/0x5d0 fs/ntfs3/fsntfs.c:272
ntfs_fill_super+0x1eff/0x37f0 fs/ntfs3/super.c:1018
get_tree_bdev+0x440/0x760 fs/super.c:1323
vfs_get_tree+0x89/0x2f0 fs/super.c:1530
do_new_mount fs/namespace.c:3040 [inline]
path_mount+0x1326/0x1e20 fs/namespace.c:3370
do_mount fs/namespace.c:3383 [inline]
__do_sys_mount fs/namespace.c:3591 [inline]
__se_sys_mount fs/namespace.c:3568 [inline]
__x64_sys_mount+0x27f/0x300 fs/namespace.c:3568
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x63/0xcd
[...]
</TASK>
The buggy address belongs to the physical page:
page:ffffea00006ef600 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x1bbd8
head:ffffea00006ef600 order:3 compound_mapcount:0 compound_pincount:0
flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff)
page dumped because: kasan: bad access detected
Memory state around the buggy address:
ffff88801bbdfe00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
ffff88801bbdfe80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff88801bbdff00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
^
ffff88801bbdff80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
ffff88801bbe0000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
Kernel will tries to read record and parse MFT from disk in
ntfs_read_mft().
Yet the problem is that during enumerating attributes in record,
kernel doesn't check whether run_off field loading from the disk
is a valid value.
To be more specific, if attr->nres.run_off is larger than attr->size,
kernel will passes an invalid argument run_buf_size in
run_unpack_ex(), which having an integer overflow. Then this invalid
argument will triggers the slab-out-of-bounds Read bug as above.
This patch solves it by adding the sanity check between
the offset to packed runs and attribute size.
link: https://lore.kernel.org/all/0000000000009145fc05e94bd5c3@google.com/#t
Reported-and-tested-by: syzbot+8d6fbb27a6aded64b25b@syzkaller.appspotmail.com
Signed-off-by: Hawkins Jiawei <yin31149@gmail.com>
Signed-off-by: Konstantin Komarov <almaz.alexandrovich@paragon-software.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 03e02acda8e267a8183e1e0ed289ff1ef9cd7ed8 ]
This is identical to eventfd_signal(), but it allows the caller to pass
in a mask to be used for the poll wakeup key. The use case is avoiding
repeated multishot triggers if we have a dependency between eventfd and
io_uring.
If we setup an eventfd context and register that as the io_uring eventfd,
and at the same time queue a multishot poll request for the eventfd
context, then any CQE posted will repeatedly trigger the multishot request
until it terminates when the CQ ring overflows.
In preparation for io_uring detecting this circular dependency, add the
mentioned helper so that io_uring can pass in EPOLL_URING as part of the
poll wakeup key.
Cc: stable@vger.kernel.org # 6.0
[axboe: fold in !CONFIG_EVENTFD fix from Zhang Qilong]
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Stable-dep-of: 4464853277d0 ("io_uring: pass in EPOLL_URING_WAKE for eventfd signaling and wakeups")
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit caf1aeaffc3b09649a56769e559333ae2c4f1802 ]
We can have dependencies between epoll and io_uring. Consider an epoll
context, identified by the epfd file descriptor, and an io_uring file
descriptor identified by iofd. If we add iofd to the epfd context, and
arm a multishot poll request for epfd with iofd, then the multishot
poll request will repeatedly trigger and generate events until terminated
by CQ ring overflow. This isn't a desired behavior.
Add EPOLL_URING so that io_uring can pass it in as part of the poll wakeup
key, and io_uring can check for that to detect a potential recursive
invocation.
Cc: stable@vger.kernel.org # 6.0
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Stable-dep-of: 4464853277d0 ("io_uring: pass in EPOLL_URING_WAKE for eventfd signaling and wakeups")
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 162d053e15fe985f754ef495a96eb3db970c43ed upstream.
If we get -ENOMEM while dropping file extent items in a given range, at
btrfs_drop_extents(), due to failure to allocate memory when attempting to
increment the reference count for an extent or drop the reference count,
we handle it with a BUG_ON(). This is excessive, instead we can simply
abort the transaction and return the error to the caller. In fact most
callers of btrfs_drop_extents(), directly or indirectly, already abort
the transaction if btrfs_drop_extents() returns any error.
Also, we already have error paths at btrfs_drop_extents() that may return
-ENOMEM and in those cases we abort the transaction, like for example
anything that changes the b+tree may return -ENOMEM due to a failure to
allocate a new extent buffer when COWing an existing extent buffer, such
as a call to btrfs_duplicate_item() for example.
So replace the BUG_ON() calls with proper logic to abort the transaction
and return the error.
Reported-by: syzbot+0b1fb6b0108c27419f9f@syzkaller.appspotmail.com
Link: https://lore.kernel.org/linux-btrfs/00000000000089773e05ee4b9cb4@google.com/
CC: stable@vger.kernel.org # 5.4+
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 672e4268b2863d7e4978dfed29552b31c2f9bd4e upstream.
ovl_dentry_revalidate_common() can be called in rcu-walk mode. As document
said, "in rcu-walk mode, d_parent and d_inode should not be used without
care".
Check inode here to protect access under rcu-walk mode.
Fixes: bccece1ead36 ("ovl: allow remote upper")
Reported-and-tested-by: syzbot+a4055c78774bbf3498bb@syzkaller.appspotmail.com
Signed-off-by: Chen Zhongjin <chenzhongjin@huawei.com>
Cc: <stable@vger.kernel.org> # v5.7
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 572302af1258459e124437b8f3369357447afac7 upstream.
Commit 57fe60df6241 ("reiserfs: add atomic addition of selinux attributes
during inode creation") defined reiserfs_security_free() to free the name
and value of a security xattr allocated by the active LSM through
security_old_inode_init_security(). However, this function is not called
in the reiserfs code.
Thus, add a call to reiserfs_security_free() whenever
reiserfs_security_init() is called, and initialize value to NULL, to avoid
to call kfree() on an uninitialized pointer.
Finally, remove the kfree() for the xattr name, as it is not allocated
anymore.
Fixes: 57fe60df6241 ("reiserfs: add atomic addition of selinux attributes during inode creation")
Cc: stable@vger.kernel.org
Cc: Jeff Mahoney <jeffm@suse.com>
Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Reported-by: Mimi Zohar <zohar@linux.ibm.com>
Reported-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
Reviewed-by: Mimi Zohar <zohar@linux.ibm.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 2f4fec5943407318b9523f01ce1f5d668c028332 ]
In commit 76d62f24db07 ("pstore: Switch pmsg_lock to an rt_mutex
to avoid priority inversion") I changed a lock to an rt_mutex.
However, its possible that CONFIG_RT_MUTEXES is not enabled,
which then results in a build failure, as the 0day bot detected:
https://lore.kernel.org/linux-mm/202212211244.TwzWZD3H-lkp@intel.com/
Thus this patch changes CONFIG_PSTORE_PMSG to select
CONFIG_RT_MUTEXES, which ensures the build will not fail.
Cc: Wei Wang <wvw@google.com>
Cc: Midas Chien<midaschieh@google.com>
Cc: Connor O'Brien <connoro@google.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Anton Vorontsov <anton@enomsg.org>
Cc: Colin Cross <ccross@android.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: kernel test robot <lkp@intel.com>
Cc: kernel-team@android.com
Fixes: 76d62f24db07 ("pstore: Switch pmsg_lock to an rt_mutex to avoid priority inversion")
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: John Stultz <jstultz@google.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20221221051855.15761-1-jstultz@google.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 36f82c93ee0bd88f1c95a52537906b8178b537f1 ]
The afs_fs_probe_dispatcher() work function is passed a count on
net->servers_outstanding when it is scheduled (which may come via its
timer). This is passed back to the work_item, passed to the timer or
dropped at the end of the dispatcher function.
But, at the top of the dispatcher function, there are two checks which
skip the rest of the function: if the network namespace is being destroyed
or if there are no fileservers to probe. These two return paths, however,
do not drop the count passed to the dispatcher, and so, sometimes, the
destruction of a network namespace, such as induced by rmmod of the kafs
module, may get stuck in afs_purge_servers(), waiting for
net->servers_outstanding to become zero.
Fix this by adding the missing decrements in afs_fs_probe_dispatcher().
Fixes: f6cbb368bcb0 ("afs: Actively poll fileservers to maintain NAT or firewall openings")
Reported-by: Marc Dionne <marc.dionne@auristor.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Tested-by: Marc Dionne <marc.dionne@auristor.com>
cc: linux-afs@lists.infradead.org
Link: https://lore.kernel.org/r/167164544917.2072364.3759519569649459359.stgit@warthog.procyon.org.uk/
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 76d62f24db07f22ccf9bc18ca793c27d4ebef721 ]
Wei Wang reported seeing priority inversion caused latencies
caused by contention on pmsg_lock, and suggested it be switched
to a rt_mutex.
I was initially hesitant this would help, as the tasks in that
trace all seemed to be SCHED_NORMAL, so the benefit would be
limited to only nice boosting.
However, another similar issue was raised where the priority
inversion was seen did involve a blocked RT task so it is clear
this would be helpful in that case.
Cc: Wei Wang <wvw@google.com>
Cc: Midas Chien<midaschieh@google.com>
Cc: Connor O'Brien <connoro@google.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Anton Vorontsov <anton@enomsg.org>
Cc: Colin Cross <ccross@android.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: kernel-team@android.com
Fixes: 9d5438f462ab ("pstore: Add pmsg - user-space accessible pstore object")
Reported-by: Wei Wang <wvw@google.com>
Signed-off-by: John Stultz <jstultz@google.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20221214231834.3711880-1-jstultz@google.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 26215b7ee923b9251f7bb12c4e5f09dc465d35f2 ]
Syzkaller reports a null-ptr-deref bug as follows:
======================================================
KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007]
RIP: 0010:hugetlbfs_parse_param+0x1dd/0x8e0 fs/hugetlbfs/inode.c:1380
[...]
Call Trace:
<TASK>
vfs_parse_fs_param fs/fs_context.c:148 [inline]
vfs_parse_fs_param+0x1f9/0x3c0 fs/fs_context.c:129
vfs_parse_fs_string+0xdb/0x170 fs/fs_context.c:191
generic_parse_monolithic+0x16f/0x1f0 fs/fs_context.c:231
do_new_mount fs/namespace.c:3036 [inline]
path_mount+0x12de/0x1e20 fs/namespace.c:3370
do_mount fs/namespace.c:3383 [inline]
__do_sys_mount fs/namespace.c:3591 [inline]
__se_sys_mount fs/namespace.c:3568 [inline]
__x64_sys_mount+0x27f/0x300 fs/namespace.c:3568
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x63/0xcd
[...]
</TASK>
======================================================
According to commit "vfs: parse: deal with zero length string value",
kernel will set the param->string to null pointer in vfs_parse_fs_string()
if fs string has zero length.
Yet the problem is that, hugetlbfs_parse_param() will dereference the
param->string, without checking whether it is a null pointer. To be more
specific, if hugetlbfs_parse_param() parses an illegal mount parameter,
such as "size=,", kernel will constructs struct fs_parameter with null
pointer in vfs_parse_fs_string(), then passes this struct fs_parameter to
hugetlbfs_parse_param(), which triggers the above null-ptr-deref bug.
This patch solves it by adding sanity check on param->string
in hugetlbfs_parse_param().
Link: https://lkml.kernel.org/r/20221020231609.4810-1-yin31149@gmail.com
Reported-by: syzbot+a3e6acd85ded5c16a709@syzkaller.appspotmail.com
Tested-by: syzbot+a3e6acd85ded5c16a709@syzkaller.appspotmail.com
Link: https://lore.kernel.org/all/0000000000005ad00405eb7148c6@google.com/
Signed-off-by: Hawkins Jiawei <yin31149@gmail.com>
Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Hawkins Jiawei <yin31149@gmail.com>
Cc: Muchun Song <songmuchun@bytedance.com>
Cc: Ian Kent <raven@themaw.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 5559405df652008e56eee88872126fe4c451da67 ]
According to commit "vfs: parse: deal with zero length string value",
kernel will set the param->string to null pointer in vfs_parse_fs_string()
if fs string has zero length.
Yet the problem is that, nfs_fs_context_parse_param() will dereferences the
param->string, without checking whether it is a null pointer, which may
trigger a null-ptr-deref bug.
This patch solves it by adding sanity check on param->string
in nfs_fs_context_parse_param().
Signed-off-by: Hawkins Jiawei <yin31149@gmail.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 8d824e69d9f3fa3121b2dda25053bae71e2460d2 ]
Syzbot reported a OOB read bug:
==================================================================
BUG: KASAN: slab-out-of-bounds in hfs_strcmp+0x117/0x190
fs/hfs/string.c:84
Read of size 1 at addr ffff88807eb62c4e by task kworker/u4:1/11
CPU: 1 PID: 11 Comm: kworker/u4:1 Not tainted
6.1.0-rc6-syzkaller-00308-g644e9524388a #0
Workqueue: writeback wb_workfn (flush-7:0)
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0x1b1/0x28e lib/dump_stack.c:106
print_address_description+0x74/0x340 mm/kasan/report.c:284
print_report+0x107/0x1f0 mm/kasan/report.c:395
kasan_report+0xcd/0x100 mm/kasan/report.c:495
hfs_strcmp+0x117/0x190 fs/hfs/string.c:84
__hfs_brec_find+0x213/0x5c0 fs/hfs/bfind.c:75
hfs_brec_find+0x276/0x520 fs/hfs/bfind.c:138
hfs_write_inode+0x34c/0xb40 fs/hfs/inode.c:462
write_inode fs/fs-writeback.c:1440 [inline]
If the input inode of hfs_write_inode() is incorrect:
struct inode
struct hfs_inode_info
struct hfs_cat_key
struct hfs_name
u8 len # len is greater than HFS_NAMELEN(31) which is the
maximum length of an HFS filename
OOB read occurred:
hfs_write_inode()
hfs_brec_find()
__hfs_brec_find()
hfs_cat_keycmp()
hfs_strcmp() # OOB read occurred due to len is too large
Fix this by adding a Check on len in hfs_write_inode() before calling
hfs_brec_find().
Link: https://lkml.kernel.org/r/20221130065959.2168236-1-zhangpeng362@huawei.com
Signed-off-by: ZhangPeng <zhangpeng362@huawei.com>
Reported-by: <syzbot+e836ff7133ac02be825f@syzkaller.appspotmail.com>
Cc: Damien Le Moal <damien.lemoal@opensource.wdc.com>
Cc: Ira Weiny <ira.weiny@intel.com>
Cc: Jeff Layton <jlayton@kernel.org>
Cc: Kefeng Wang <wangkefeng.wang@huawei.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Nanyong Sun <sunnanyong@huawei.com>
Cc: Viacheslav Dubeyko <slava@dubeyko.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 5a75034e71ef5ec0fce983afcb6c9cb0147cd5b9 ]
We sometimes have to allocate new extent states when clearing or setting
new bits in an extent io tree. Generally we preallocate this before
taking the tree spin lock, but we can use this preallocated extent state
sometimes and then need to try to do a GFP_ATOMIC allocation under the
lock.
Unfortunately sometimes this fails, and then we hit the BUG_ON() and
bring the box down. This happens roughly 20 times a week in our fleet.
However the vast majority of callers use GFP_NOFS, which means that if
this GFP_ATOMIC allocation fails, we could simply drop the spin lock, go
back and allocate a new extent state with our given gfp mask, and begin
again from where we left off.
For the remaining callers that do not use GFP_NOFS, they are generally
using GFP_NOWAIT, which still allows for some reclaim. So allow these
allocations to attempt to happen outside of the spin lock so we don't
need to rely on GFP_ATOMIC allocations.
This in essence creates an infinite loop for anything that isn't
GFP_NOFS. To address this we may want to migrate to using mempools for
extent states so that we will always have emergency reserves in order to
make our allocations.
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit ebeccaaef67a4895d2496ab8d9c2fb8d89201211 ]
If field s_log_block_size of superblock data is corrupted and too large,
init_nilfs() and load_nilfs() still can trigger a shift-out-of-bounds
warning followed by a kernel panic (if panic_on_warn is set):
shift exponent 38973 is too large for 32-bit type 'int'
Call Trace:
<TASK>
dump_stack_lvl+0xcd/0x134
ubsan_epilogue+0xb/0x50
__ubsan_handle_shift_out_of_bounds.cold.12+0x17b/0x1f5
init_nilfs.cold.11+0x18/0x1d [nilfs2]
nilfs_mount+0x9b5/0x12b0 [nilfs2]
...
This fixes the issue by adding and using a new helper function for getting
block size with sanity check.
Link: https://lkml.kernel.org/r/20221027044306.42774-3-konishi.ryusuke@gmail.com
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Tested-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 610a2a3d7d8be3537458a378ec69396a76c385b6 ]
Patch series "nilfs2: fix UBSAN shift-out-of-bounds warnings on mount
time".
The first patch fixes a bug reported by syzbot, and the second one fixes
the remaining bug of the same kind. Although they are triggered by the
same super block data anomaly, I divided it into the above two because the
details of the issues and how to fix it are different.
Both are required to eliminate the shift-out-of-bounds issues at mount
time.
This patch (of 2):
If the block size exponent information written in an on-disk superblock is
corrupted, nilfs_sb2_bad_offset helper function can trigger
shift-out-of-bounds warning followed by a kernel panic (if panic_on_warn
is set):
shift exponent 38983 is too large for 64-bit type 'unsigned long long'
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0x1b1/0x28e lib/dump_stack.c:106
ubsan_epilogue lib/ubsan.c:151 [inline]
__ubsan_handle_shift_out_of_bounds+0x33d/0x3b0 lib/ubsan.c:322
nilfs_sb2_bad_offset fs/nilfs2/the_nilfs.c:449 [inline]
nilfs_load_super_block+0xdf5/0xe00 fs/nilfs2/the_nilfs.c:523
init_nilfs+0xb7/0x7d0 fs/nilfs2/the_nilfs.c:577
nilfs_fill_super+0xb1/0x5d0 fs/nilfs2/super.c:1047
nilfs_mount+0x613/0x9b0 fs/nilfs2/super.c:1317
...
In addition, since nilfs_sb2_bad_offset() performs multiplication without
considering the upper bound, the computation may overflow if the disk
layout parameters are not normal.
This fixes these issues by inserting preliminary sanity checks for those
parameters and by converting the comparison from one involving
multiplication and left bit-shifting to one using division and right
bit-shifting.
Link: https://lkml.kernel.org/r/20221027044306.42774-1-konishi.ryusuke@gmail.com
Link: https://lkml.kernel.org/r/20221027044306.42774-2-konishi.ryusuke@gmail.com
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Reported-by: syzbot+e91619dd4c11c4960706@syzkaller.appspotmail.com
Tested-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 25e70c6162f207828dd405b432d8f2a98dbf7082 ]
This should be applied to most URSAN bugs found recently by syzbot,
by guarding the dbMount. As syzbot feeding rubbish into the bmap
descriptor.
Signed-off-by: Hoi Pok Wu <wuhoipok@gmail.com>
Signed-off-by: Dave Kleikamp <dave.kleikamp@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit ebe060369f8d6e4588b115f252bebf5ba4d64350 ]
JFS has in jfs_incore.h:
/* _inline may overflow into _inline_ea when needed */
/* _inline_ea may overlay the last part of
* file._xtroot if maxentry = XTROOTINITSLOT
*/
union {
struct {
/* 128: inline symlink */
unchar _inline[128];
/* 128: inline extended attr */
unchar _inline_ea[128];
};
unchar _inline_all[256];
and currently the symlink code copies into _inline;
if this is larger than 128 bytes it triggers a fortify warning of the
form:
memcpy: detected field-spanning write (size 132) of single field
"ip->i_link" at fs/jfs/namei.c:950 (size 18446744073709551615)
when it's actually OK.
Copy it into _inline_all instead.
Reported-by: syzbot+5fc38b2ddbbca7f5c680@syzkaller.appspotmail.com
Signed-off-by: Dr. David Alan Gilbert <linux@treblig.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Dave Kleikamp <dave.kleikamp@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit c791730f2554a9ebb8f18df9368dc27d4ebc38c2 ]
syzbot reported a warning like below [1]:
VFS: brelse: Trying to free free buffer
WARNING: CPU: 2 PID: 7301 at fs/buffer.c:1145 __brelse+0x67/0xa0
...
Call Trace:
<TASK>
invalidate_bh_lru+0x99/0x150
smp_call_function_many_cond+0xe2a/0x10c0
? generic_remap_file_range_prep+0x50/0x50
? __brelse+0xa0/0xa0
? __mutex_lock+0x21c/0x12d0
? smp_call_on_cpu+0x250/0x250
? rcu_read_lock_sched_held+0xb/0x60
? lock_release+0x587/0x810
? __brelse+0xa0/0xa0
? generic_remap_file_range_prep+0x50/0x50
on_each_cpu_cond_mask+0x3c/0x80
blkdev_flush_mapping+0x13a/0x2f0
blkdev_put_whole+0xd3/0xf0
blkdev_put+0x222/0x760
deactivate_locked_super+0x96/0x160
deactivate_super+0xda/0x100
cleanup_mnt+0x222/0x3d0
task_work_run+0x149/0x240
? task_work_cancel+0x30/0x30
do_exit+0xb29/0x2a40
? reacquire_held_locks+0x4a0/0x4a0
? do_raw_spin_lock+0x12a/0x2b0
? mm_update_next_owner+0x7c0/0x7c0
? rwlock_bug.part.0+0x90/0x90
? zap_other_threads+0x234/0x2d0
do_group_exit+0xd0/0x2a0
__x64_sys_exit_group+0x3a/0x50
do_syscall_64+0x34/0xb0
entry_SYSCALL_64_after_hwframe+0x63/0xcd
The cause of the issue is that brelse() is called on both ofibh.sbh
and ofibh.ebh by udf_find_entry() when it returns NULL. However,
brelse() is called by udf_rename(), too. So, b_count on buffer_head
becomes unbalanced.
This patch fixes the issue by not calling brelse() by udf_rename()
when udf_find_entry() returns NULL.
Link: https://syzkaller.appspot.com/bug?id=8297f45698159c6bca8a1f87dc983667c1a1c851 [1]
Reported-by: syzbot+7902cd7684bc35306224@syzkaller.appspotmail.com
Signed-off-by: Shigeru Yoshida <syoshida@redhat.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20221023095741.271430-1-syoshida@redhat.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 898f706695682b9954f280d95e49fa86ffa55d08 ]
Syzbot found a crash : UBSAN: shift-out-of-bounds in dbAllocAG. The
underlying bug is the missing check of bmp->db_agl2size. The field can
be greater than 64 and trigger the shift-out-of-bounds.
Fix this bug by adding a check of bmp->db_agl2size in dbMount since this
field is used in many following functions. The upper bound for this
field is L2MAXL2SIZE - L2MAXAG, thanks for the help of Dave Kleikamp.
Note that, for maintenance, I reorganized error handling code of dbMount.
Reported-by: syzbot+15342c1aa6a00fb7a438@syzkaller.appspotmail.com
Signed-off-by: Dongliang Mu <mudongliangabcd@gmail.com>
Signed-off-by: Dave Kleikamp <dave.kleikamp@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 6a46bf558803dd2b959ca7435a5c143efe837217 ]
UBSAN reported a shift-out-of-bounds warning:
left shift of 1 by 31 places cannot be represented in type 'int'
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0x8d/0xcf lib/dump_stack.c:106
ubsan_epilogue+0xa/0x44 lib/ubsan.c:151
__ubsan_handle_shift_out_of_bounds+0x1e7/0x208 lib/ubsan.c:322
check_special_flags fs/binfmt_misc.c:241 [inline]
create_entry fs/binfmt_misc.c:456 [inline]
bm_register_write+0x9d3/0xa20 fs/binfmt_misc.c:654
vfs_write+0x11e/0x580 fs/read_write.c:582
ksys_write+0xcf/0x120 fs/read_write.c:637
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x34/0x80 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x4194e1
Since the type of Node's flags is unsigned long, we should define these
macros with same type too.
Signed-off-by: Liu Shixin <liushixin2@huawei.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20221102025123.1117184-1-liushixin2@huawei.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit f60ffa662d1427cfd31fe9d895c3566ac50bfe52 ]
A NULL error response might be a valid case where smb2_reconnect()
failed to reconnect the session and tcon due to a disconnected server
prior to issuing the I/O operation, so don't leak -ENOMEM to userspace
on such occasions.
Fixes: 76894f3e2f71 ("cifs: improve symlink handling for smb2+")
Signed-off-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Signed-off-by: Steve French <stfrench@microsoft.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 557d19675a470bb0a98beccec38c5dc3735c20fa ]
Syzbot reports an out of bound access in ntfs_trim_fs.
The cause of this is using a loop termination condition that compares
window index (iw) with wnd->nbits instead of wnd->nwnd, due to which the
index used for wnd->free_bits exceeds the size of the array allocated.
Fix the loop condition.
Fixes: 3f3b442b5ad2 ("fs/ntfs3: Add bitmap")
Link: https://syzkaller.appspot.com/bug?extid=b892240eac461e488d51
Reported-by: syzbot+b892240eac461e488d51@syzkaller.appspotmail.com
Signed-off-by: Abdun Nihaal <abdun.nihaal@gmail.com>
Signed-off-by: Konstantin Komarov <almaz.alexandrovich@paragon-software.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit e001e60869390686809663c02bceb1d3922548fb ]
Smatch complains that the "add_bytes" is not to be trusted. Use
size_add() to prevent an integer overflow.
Fixes: be71b5cba2e6 ("fs/ntfs3: Add attrib operations")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Konstantin Komarov <almaz.alexandrovich@paragon-software.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Christian Brauner
Al Viro
Zhang Tianci
Wang Yufen
Aditya Garg
Qiujun Huang
Luca Stefani
Dai Ngo
Yin Xiujiang
Dan Carpenter
Tetsuo Handa
Edward Lo
Hawkins Jiawei
Shigeru Yoshida
Jens Axboe
Filipe Manana
Chen Zhongjin
Roberto Sassu
John Stultz
David Howells
Zhang Xiaoxu
ZhangPeng
Josef Bacik
Ryusuke Konishi
Hoi Pok Wu
Dr. David Alan Gilbert
Dongliang Mu
Liu Shixin
Paulo Alcantara
Dan Aloni
Abdun Nihaal