linux-stable.git/include, branch v5.4.294 Linux kernel stable tree coredump: hand a pidfd to the usermode coredump helper 2025-06-04T12:32:36+00:00 Christian Brauner brauner@kernel.org 2025-06-02T11:16:07+00:00 79bf58c7c4b7e351331f0344359307836452e70c commit b5325b2a270fcaf7b2a9a0f23d422ca8a5a8bdea upstream. Give userspace a way to instruct the kernel to install a pidfd into the usermode helper process. This makes coredump handling a lot more reliable for userspace. In parallel with this commit we already have systemd adding support for this in [1]. We create a pidfs file for the coredumping process when we process the corename pattern. When the usermode helper process is forked we then install the pidfs file as file descriptor three into the usermode helpers file descriptor table so it's available to the exec'd program. Since usermode helpers are either children of the system_unbound_wq workqueue or kthreadd we know that the file descriptor table is empty and can thus always use three as the file descriptor number. Note, that we'll install a pidfd for the thread-group leader even if a subthread is calling do_coredump(). We know that task linkage hasn't been removed due to delay_group_leader() and even if this @current isn't the actual thread-group leader we know that the thread-group leader cannot be reaped until @current has exited. [brauner: This is a backport for the v5.4 series. Upstream has significantly changed and backporting all that infra is a non-starter. So simply backport the pidfd_prepare() helper and waste the file descriptor we allocated. Then we minimally massage the umh coredump setup code.] Link: https://github.com/systemd/systemd/pull/37125 [1] Link: https://lore.kernel.org/20250414-work-coredump-v2-3-685bf231f828@kernel.org Tested-by: Luca Boccassi <luca.boccassi@gmail.com> Reviewed-by: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Christian Brauner <brauner@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit b5325b2a270fcaf7b2a9a0f23d422ca8a5a8bdea upstream.

Give userspace a way to instruct the kernel to install a pidfd into the
usermode helper process. This makes coredump handling a lot more
reliable for userspace. In parallel with this commit we already have
systemd adding support for this in [1].

We create a pidfs file for the coredumping process when we process the
corename pattern. When the usermode helper process is forked we then
install the pidfs file as file descriptor three into the usermode
helpers file descriptor table so it's available to the exec'd program.

Since usermode helpers are either children of the system_unbound_wq
workqueue or kthreadd we know that the file descriptor table is empty
and can thus always use three as the file descriptor number.

Note, that we'll install a pidfd for the thread-group leader even if a
subthread is calling do_coredump(). We know that task linkage hasn't
been removed due to delay_group_leader() and even if this @current isn't
the actual thread-group leader we know that the thread-group leader
cannot be reaped until @current has exited.

[brauner: This is a backport for the v5.4 series. Upstream has
significantly changed and backporting all that infra is a non-starter.
So simply backport the pidfd_prepare() helper and waste the file
descriptor we allocated. Then we minimally massage the umh coredump
setup code.]

Link: https://github.com/systemd/systemd/pull/37125 [1]
Link: https://lore.kernel.org/20250414-work-coredump-v2-3-685bf231f828@kernel.org
Tested-by: Luca Boccassi <luca.boccassi@gmail.com>
Reviewed-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Christian Brauner <brauner@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
pid: add pidfd_prepare() 2025-06-04T12:32:36+00:00 Christian Brauner brauner@kernel.org 2023-03-27T18:22:51+00:00 0a841d0a481e828c3e1211743c93788927a23b28 commit 6ae930d9dbf2d093157be33428538c91966d8a9f upstream. Add a new helper that allows to reserve a pidfd and allocates a new pidfd file that stashes the provided struct pid. This will allow us to remove places that either open code this function or that call pidfd_create() but then have to call close_fd() because there are still failure points after pidfd_create() has been called. Reviewed-by: Jan Kara <jack@suse.cz> Message-Id: <20230327-pidfd-file-api-v1-1-5c0e9a3158e4@kernel.org> Signed-off-by: Christian Brauner <brauner@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 6ae930d9dbf2d093157be33428538c91966d8a9f upstream.

Add a new helper that allows to reserve a pidfd and allocates a new
pidfd file that stashes the provided struct pid. This will allow us to
remove places that either open code this function or that call
pidfd_create() but then have to call close_fd() because there are still
failure points after pidfd_create() has been called.

Reviewed-by: Jan Kara <jack@suse.cz>
Message-Id: <20230327-pidfd-file-api-v1-1-5c0e9a3158e4@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
pidfd: check pid has attached task in fdinfo 2025-06-04T12:32:36+00:00 Christian Brauner christian.brauner@ubuntu.com 2019-10-17T10:18:28+00:00 53df781e0bd6db925b30f5b6a10798eef14896eb commit 3d6d8da48d0b214d65ea0227d47228abc75d7c88 upstream. Currently, when a task is dead we still print the pid it used to use in the fdinfo files of its pidfds. This doesn't make much sense since the pid may have already been reused. So verify that the task is still alive by introducing the pid_has_task() helper which will be used by other callers in follow-up patches. If the task is not alive anymore, we will print -1. This allows us to differentiate between a task not being present in a given pid namespace - in which case we already print 0 - and a task having been reaped. Note that this uses PIDTYPE_PID for the check. Technically, we could've checked PIDTYPE_TGID since pidfds currently only refer to thread-group leaders but if they won't anymore in the future then this check becomes problematic without it being immediately obvious to non-experts imho. If a thread is created via clone(CLONE_THREAD) than struct pid has a single non-empty list pid->tasks[PIDTYPE_PID] and this pid can't be used as a PIDTYPE_TGID meaning pid->tasks[PIDTYPE_TGID] will return NULL even though the thread-group leader might still be very much alive. So checking PIDTYPE_PID is fine and is easier to maintain should we ever allow pidfds to refer to threads. Cc: Jann Horn <jannh@google.com> Cc: Christian Kellner <christian@kellner.me> Cc: linux-api@vger.kernel.org Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com> Reviewed-by: Oleg Nesterov <oleg@redhat.com> Link: https://lore.kernel.org/r/20191017101832.5985-1-christian.brauner@ubuntu.com Signed-off-by: Christian Brauner <brauner@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 3d6d8da48d0b214d65ea0227d47228abc75d7c88 upstream.

Currently, when a task is dead we still print the pid it used to use in
the fdinfo files of its pidfds. This doesn't make much sense since the
pid may have already been reused. So verify that the task is still alive
by introducing the pid_has_task() helper which will be used by other
callers in follow-up patches.
If the task is not alive anymore, we will print -1. This allows us to
differentiate between a task not being present in a given pid namespace
- in which case we already print 0 - and a task having been reaped.

Note that this uses PIDTYPE_PID for the check. Technically, we could've
checked PIDTYPE_TGID since pidfds currently only refer to thread-group
leaders but if they won't anymore in the future then this check becomes
problematic without it being immediately obvious to non-experts imho. If
a thread is created via clone(CLONE_THREAD) than struct pid has a single
non-empty list pid->tasks[PIDTYPE_PID] and this pid can't be used as a
PIDTYPE_TGID meaning pid->tasks[PIDTYPE_TGID] will return NULL even
though the thread-group leader might still be very much alive. So
checking PIDTYPE_PID is fine and is easier to maintain should we ever
allow pidfds to refer to threads.

Cc: Jann Horn <jannh@google.com>
Cc: Christian Kellner <christian@kellner.me>
Cc: linux-api@vger.kernel.org
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
Reviewed-by: Oleg Nesterov <oleg@redhat.com>
Link: https://lore.kernel.org/r/20191017101832.5985-1-christian.brauner@ubuntu.com
Signed-off-by: Christian Brauner <brauner@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
netfilter: nf_tables: do not defer rule destruction via call_rcu 2025-06-04T12:32:36+00:00 Florian Westphal fw@strlen.de 2025-05-29T09:11:44+00:00 5146c27b2780aac59876a887a5f4e793b8949862 commit b04df3da1b5c6f6dc7cdccc37941740c078c4043 upstream. nf_tables_chain_destroy can sleep, it can't be used from call_rcu callbacks. Moreover, nf_tables_rule_release() is only safe for error unwinding, while transaction mutex is held and the to-be-desroyed rule was not exposed to either dataplane or dumps, as it deactives+frees without the required synchronize_rcu() in-between. nft_rule_expr_deactivate() callbacks will change ->use counters of other chains/sets, see e.g. nft_lookup .deactivate callback, these must be serialized via transaction mutex. Also add a few lockdep asserts to make this more explicit. Calling synchronize_rcu() isn't ideal, but fixing this without is hard and way more intrusive. As-is, we can get: WARNING: .. net/netfilter/nf_tables_api.c:5515 nft_set_destroy+0x.. Workqueue: events nf_tables_trans_destroy_work RIP: 0010:nft_set_destroy+0x3fe/0x5c0 Call Trace: <TASK> nf_tables_trans_destroy_work+0x6b7/0xad0 process_one_work+0x64a/0xce0 worker_thread+0x613/0x10d0 In case the synchronize_rcu becomes an issue, we can explore alternatives. One way would be to allocate nft_trans_rule objects + one nft_trans_chain object, deactivate the rules + the chain and then defer the freeing to the nft destroy workqueue. We'd still need to keep the synchronize_rcu path as a fallback to handle -ENOMEM corner cases though. Reported-by: syzbot+b26935466701e56cfdc2@syzkaller.appspotmail.com Closes: https://lore.kernel.org/all/67478d92.050a0220.253251.0062.GAE@google.com/T/ Fixes: c03d278fdf35 ("netfilter: nf_tables: wait for rcu grace period on net_device removal") Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit b04df3da1b5c6f6dc7cdccc37941740c078c4043 upstream.

nf_tables_chain_destroy can sleep, it can't be used from call_rcu
callbacks.

Moreover, nf_tables_rule_release() is only safe for error unwinding,
while transaction mutex is held and the to-be-desroyed rule was not
exposed to either dataplane or dumps, as it deactives+frees without
the required synchronize_rcu() in-between.

nft_rule_expr_deactivate() callbacks will change ->use counters
of other chains/sets, see e.g. nft_lookup .deactivate callback, these
must be serialized via transaction mutex.

Also add a few lockdep asserts to make this more explicit.

Calling synchronize_rcu() isn't ideal, but fixing this without is hard
and way more intrusive.  As-is, we can get:

WARNING: .. net/netfilter/nf_tables_api.c:5515 nft_set_destroy+0x..
Workqueue: events nf_tables_trans_destroy_work
RIP: 0010:nft_set_destroy+0x3fe/0x5c0
Call Trace:
 <TASK>
 nf_tables_trans_destroy_work+0x6b7/0xad0
 process_one_work+0x64a/0xce0
 worker_thread+0x613/0x10d0

In case the synchronize_rcu becomes an issue, we can explore alternatives.

One way would be to allocate nft_trans_rule objects + one nft_trans_chain
object, deactivate the rules + the chain and then defer the freeing to the
nft destroy workqueue.  We'd still need to keep the synchronize_rcu path as
a fallback to handle -ENOMEM corner cases though.

Reported-by: syzbot+b26935466701e56cfdc2@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/all/67478d92.050a0220.253251.0062.GAE@google.com/T/
Fixes: c03d278fdf35 ("netfilter: nf_tables: wait for rcu grace period on net_device removal")
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
netfilter: nf_tables: wait for rcu grace period on net_device removal 2025-06-04T12:32:36+00:00 Pablo Neira Ayuso pablo@netfilter.org 2025-05-29T09:11:43+00:00 9eee6097ffb26cdd2adb988c0d378fa0d650c737 commit c03d278fdf35e73dd0ec543b9b556876b9d9a8dc upstream. 8c873e219970 ("netfilter: core: free hooks with call_rcu") removed synchronize_net() call when unregistering basechain hook, however, net_device removal event handler for the NFPROTO_NETDEV was not updated to wait for RCU grace period. Note that 835b803377f5 ("netfilter: nf_tables_netdev: unregister hooks on net_device removal") does not remove basechain rules on device removal, I was hinted to remove rules on net_device removal later, see 5ebe0b0eec9d ("netfilter: nf_tables: destroy basechain and rules on netdevice removal"). Although NETDEV_UNREGISTER event is guaranteed to be handled after synchronize_net() call, this path needs to wait for rcu grace period via rcu callback to release basechain hooks if netns is alive because an ongoing netlink dump could be in progress (sockets hold a reference on the netns). Note that nf_tables_pre_exit_net() unregisters and releases basechain hooks but it is possible to see NETDEV_UNREGISTER at a later stage in the netns exit path, eg. veth peer device in another netns: cleanup_net() default_device_exit_batch() unregister_netdevice_many_notify() notifier_call_chain() nf_tables_netdev_event() __nft_release_basechain() In this particular case, same rule of thumb applies: if netns is alive, then wait for rcu grace period because netlink dump in the other netns could be in progress. Otherwise, if the other netns is going away then no netlink dump can be in progress and basechain hooks can be released inmediately. While at it, turn WARN_ON() into WARN_ON_ONCE() for the basechain validation, which should not ever happen. Fixes: 835b803377f5 ("netfilter: nf_tables_netdev: unregister hooks on net_device removal") Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit c03d278fdf35e73dd0ec543b9b556876b9d9a8dc upstream.

8c873e219970 ("netfilter: core: free hooks with call_rcu") removed
synchronize_net() call when unregistering basechain hook, however,
net_device removal event handler for the NFPROTO_NETDEV was not updated
to wait for RCU grace period.

Note that 835b803377f5 ("netfilter: nf_tables_netdev: unregister hooks
on net_device removal") does not remove basechain rules on device
removal, I was hinted to remove rules on net_device removal later, see
5ebe0b0eec9d ("netfilter: nf_tables: destroy basechain and rules on
netdevice removal").

Although NETDEV_UNREGISTER event is guaranteed to be handled after
synchronize_net() call, this path needs to wait for rcu grace period via
rcu callback to release basechain hooks if netns is alive because an
ongoing netlink dump could be in progress (sockets hold a reference on
the netns).

Note that nf_tables_pre_exit_net() unregisters and releases basechain
hooks but it is possible to see NETDEV_UNREGISTER at a later stage in
the netns exit path, eg. veth peer device in another netns:

 cleanup_net()
  default_device_exit_batch()
   unregister_netdevice_many_notify()
    notifier_call_chain()
     nf_tables_netdev_event()
      __nft_release_basechain()

In this particular case, same rule of thumb applies: if netns is alive,
then wait for rcu grace period because netlink dump in the other netns
could be in progress. Otherwise, if the other netns is going away then
no netlink dump can be in progress and basechain hooks can be released
inmediately.

While at it, turn WARN_ON() into WARN_ON_ONCE() for the basechain
validation, which should not ever happen.

Fixes: 835b803377f5 ("netfilter: nf_tables_netdev: unregister hooks on net_device removal")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
ALSA: pcm: Fix race of buffer access at PCM OSS layer 2025-06-04T12:32:35+00:00 Takashi Iwai tiwai@suse.de 2025-05-16T08:08:16+00:00 c0e05a76fc727929524ef24a19c302e6dd40233f commit 93a81ca0657758b607c3f4ba889ae806be9beb73 upstream. The PCM OSS layer tries to clear the buffer with the silence data at initialization (or reconfiguration) of a stream with the explicit call of snd_pcm_format_set_silence() with runtime->dma_area. But this may lead to a UAF because the accessed runtime->dma_area might be freed concurrently, as it's performed outside the PCM ops. For avoiding it, move the code into the PCM core and perform it inside the buffer access lock, so that it won't be changed during the operation. Reported-by: syzbot+32d4647f551007595173@syzkaller.appspotmail.com Closes: https://lore.kernel.org/68164d8e.050a0220.11da1b.0019.GAE@google.com Cc: <stable@vger.kernel.org> Link: https://patch.msgid.link/20250516080817.20068-1-tiwai@suse.de Signed-off-by: Takashi Iwai <tiwai@suse.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 93a81ca0657758b607c3f4ba889ae806be9beb73 upstream.

The PCM OSS layer tries to clear the buffer with the silence data at
initialization (or reconfiguration) of a stream with the explicit call
of snd_pcm_format_set_silence() with runtime->dma_area.  But this may
lead to a UAF because the accessed runtime->dma_area might be freed
concurrently, as it's performed outside the PCM ops.

For avoiding it, move the code into the PCM core and perform it inside
the buffer access lock, so that it won't be changed during the
operation.

Reported-by: syzbot+32d4647f551007595173@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/68164d8e.050a0220.11da1b.0019.GAE@google.com
Cc: <stable@vger.kernel.org>
Link: https://patch.msgid.link/20250516080817.20068-1-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
btrfs: correct the order of prelim_ref arguments in btrfs__prelim_ref 2025-06-04T12:32:35+00:00 Goldwyn Rodrigues rgoldwyn@suse.de 2025-04-25T13:25:06+00:00 5755b6731655e248c4f1d52a2e1b18795b4a2a3a [ Upstream commit bc7e0975093567f51be8e1bdf4aa5900a3cf0b1e ] btrfs_prelim_ref() calls the old and new reference variables in the incorrect order. This causes a NULL pointer dereference because oldref is passed as NULL to trace_btrfs_prelim_ref_insert(). Note, trace_btrfs_prelim_ref_insert() is being called with newref as oldref (and oldref as NULL) on purpose in order to print out the values of newref. To reproduce: echo 1 > /sys/kernel/debug/tracing/events/btrfs/btrfs_prelim_ref_insert/enable Perform some writeback operations. Backtrace: BUG: kernel NULL pointer dereference, address: 0000000000000018 #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page PGD 115949067 P4D 115949067 PUD 11594a067 PMD 0 Oops: Oops: 0000 [#1] SMP NOPTI CPU: 1 UID: 0 PID: 1188 Comm: fsstress Not tainted 6.15.0-rc2-tester+ #47 PREEMPT(voluntary) 7ca2cef72d5e9c600f0c7718adb6462de8149622 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.16.3-2-gc13ff2cd-prebuilt.qemu.org 04/01/2014 RIP: 0010:trace_event_raw_event_btrfs__prelim_ref+0x72/0x130 Code: e8 43 81 9f ff 48 85 c0 74 78 4d 85 e4 0f 84 8f 00 00 00 49 8b 94 24 c0 06 00 00 48 8b 0a 48 89 48 08 48 8b 52 08 48 89 50 10 <49> 8b 55 18 48 89 50 18 49 8b 55 20 48 89 50 20 41 0f b6 55 28 88 RSP: 0018:ffffce44820077a0 EFLAGS: 00010286 RAX: ffff8c6b403f9014 RBX: ffff8c6b55825730 RCX: 304994edf9cf506b RDX: d8b11eb7f0fdb699 RSI: ffff8c6b403f9010 RDI: ffff8c6b403f9010 RBP: 0000000000000001 R08: 0000000000000001 R09: 0000000000000010 R10: 00000000ffffffff R11: 0000000000000000 R12: ffff8c6b4e8fb000 R13: 0000000000000000 R14: ffffce44820077a8 R15: ffff8c6b4abd1540 FS: 00007f4dc6813740(0000) GS:ffff8c6c1d378000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000018 CR3: 000000010eb42000 CR4: 0000000000750ef0 PKRU: 55555554 Call Trace: <TASK> prelim_ref_insert+0x1c1/0x270 find_parent_nodes+0x12a6/0x1ee0 ? __entry_text_end+0x101f06/0x101f09 ? srso_alias_return_thunk+0x5/0xfbef5 ? srso_alias_return_thunk+0x5/0xfbef5 ? srso_alias_return_thunk+0x5/0xfbef5 ? srso_alias_return_thunk+0x5/0xfbef5 btrfs_is_data_extent_shared+0x167/0x640 ? fiemap_process_hole+0xd0/0x2c0 extent_fiemap+0xa5c/0xbc0 ? __entry_text_end+0x101f05/0x101f09 btrfs_fiemap+0x7e/0xd0 do_vfs_ioctl+0x425/0x9d0 __x64_sys_ioctl+0x75/0xc0 Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit bc7e0975093567f51be8e1bdf4aa5900a3cf0b1e ]

btrfs_prelim_ref() calls the old and new reference variables in the
incorrect order. This causes a NULL pointer dereference because oldref
is passed as NULL to trace_btrfs_prelim_ref_insert().

Note, trace_btrfs_prelim_ref_insert() is being called with newref as
oldref (and oldref as NULL) on purpose in order to print out
the values of newref.

To reproduce:
echo 1 > /sys/kernel/debug/tracing/events/btrfs/btrfs_prelim_ref_insert/enable

Perform some writeback operations.

Backtrace:
BUG: kernel NULL pointer dereference, address: 0000000000000018
 #PF: supervisor read access in kernel mode
 #PF: error_code(0x0000) - not-present page
 PGD 115949067 P4D 115949067 PUD 11594a067 PMD 0
 Oops: Oops: 0000 [#1] SMP NOPTI
 CPU: 1 UID: 0 PID: 1188 Comm: fsstress Not tainted 6.15.0-rc2-tester+ #47 PREEMPT(voluntary)  7ca2cef72d5e9c600f0c7718adb6462de8149622
 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.16.3-2-gc13ff2cd-prebuilt.qemu.org 04/01/2014
 RIP: 0010:trace_event_raw_event_btrfs__prelim_ref+0x72/0x130
 Code: e8 43 81 9f ff 48 85 c0 74 78 4d 85 e4 0f 84 8f 00 00 00 49 8b 94 24 c0 06 00 00 48 8b 0a 48 89 48 08 48 8b 52 08 48 89 50 10 <49> 8b 55 18 48 89 50 18 49 8b 55 20 48 89 50 20 41 0f b6 55 28 88
 RSP: 0018:ffffce44820077a0 EFLAGS: 00010286
 RAX: ffff8c6b403f9014 RBX: ffff8c6b55825730 RCX: 304994edf9cf506b
 RDX: d8b11eb7f0fdb699 RSI: ffff8c6b403f9010 RDI: ffff8c6b403f9010
 RBP: 0000000000000001 R08: 0000000000000001 R09: 0000000000000010
 R10: 00000000ffffffff R11: 0000000000000000 R12: ffff8c6b4e8fb000
 R13: 0000000000000000 R14: ffffce44820077a8 R15: ffff8c6b4abd1540
 FS:  00007f4dc6813740(0000) GS:ffff8c6c1d378000(0000) knlGS:0000000000000000
 CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 CR2: 0000000000000018 CR3: 000000010eb42000 CR4: 0000000000750ef0
 PKRU: 55555554
 Call Trace:
  <TASK>
  prelim_ref_insert+0x1c1/0x270
  find_parent_nodes+0x12a6/0x1ee0
  ? __entry_text_end+0x101f06/0x101f09
  ? srso_alias_return_thunk+0x5/0xfbef5
  ? srso_alias_return_thunk+0x5/0xfbef5
  ? srso_alias_return_thunk+0x5/0xfbef5
  ? srso_alias_return_thunk+0x5/0xfbef5
  btrfs_is_data_extent_shared+0x167/0x640
  ? fiemap_process_hole+0xd0/0x2c0
  extent_fiemap+0xa5c/0xbc0
  ? __entry_text_end+0x101f05/0x101f09
  btrfs_fiemap+0x7e/0xd0
  do_vfs_ioctl+0x425/0x9d0
  __x64_sys_ioctl+0x75/0xc0

Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
drm/atomic: clarify the rules around drm_atomic_state->allow_modeset 2025-06-04T12:32:34+00:00 Simona Vetter simona.vetter@ffwll.ch 2025-01-08T17:24:16+00:00 70589698329364e9fdbcab3551b24702517bd409 [ Upstream commit c5e3306a424b52e38ad2c28c7f3399fcd03e383d ] msm is automagically upgrading normal commits to full modesets, and that's a big no-no: - for one this results in full on->off->on transitions on all these crtc, at least if you're using the usual helpers. Which seems to be the case, and is breaking uapi - further even if the ctm change itself would not result in flicker, this can hide modesets for other reasons. Which again breaks the uapi v2: I forgot the case of adding unrelated crtc state. Add that case and link to the existing kerneldoc explainers. This has come up in an irc discussion with Manasi and Ville about intel's bigjoiner mode. Also cc everyone involved in the msm irc discussion, more people joined after I sent out v1. v3: Wording polish from Pekka and Thomas Acked-by: Pekka Paalanen <pekka.paalanen@collabora.com> Acked-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org> Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com> Cc: Maxime Ripard <mripard@kernel.org> Cc: Thomas Zimmermann <tzimmermann@suse.de> Cc: David Airlie <airlied@gmail.com> Cc: Daniel Vetter <daniel@ffwll.ch> Cc: Pekka Paalanen <pekka.paalanen@collabora.com> Cc: Rob Clark <robdclark@gmail.com> Cc: Simon Ser <contact@emersion.fr> Cc: Manasi Navare <navaremanasi@google.com> Cc: Ville Syrjälä <ville.syrjala@linux.intel.com> Cc: Abhinav Kumar <quic_abhinavk@quicinc.com> Cc: Dmitry Baryshkov <dmitry.baryshkov@linaro.org> Signed-off-by: Simona Vetter <simona.vetter@intel.com> Signed-off-by: Simona Vetter <simona.vetter@ffwll.ch> Link: https://patchwork.freedesktop.org/patch/msgid/20250108172417.160831-1-simona.vetter@ffwll.ch Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit c5e3306a424b52e38ad2c28c7f3399fcd03e383d ]

msm is automagically upgrading normal commits to full modesets, and
that's a big no-no:

- for one this results in full on->off->on transitions on all these
  crtc, at least if you're using the usual helpers. Which seems to be
  the case, and is breaking uapi

- further even if the ctm change itself would not result in flicker,
  this can hide modesets for other reasons. Which again breaks the
  uapi

v2: I forgot the case of adding unrelated crtc state. Add that case
and link to the existing kerneldoc explainers. This has come up in an
irc discussion with Manasi and Ville about intel's bigjoiner mode.
Also cc everyone involved in the msm irc discussion, more people
joined after I sent out v1.

v3: Wording polish from Pekka and Thomas

Acked-by: Pekka Paalanen <pekka.paalanen@collabora.com>
Acked-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Maxime Ripard <mripard@kernel.org>
Cc: Thomas Zimmermann <tzimmermann@suse.de>
Cc: David Airlie <airlied@gmail.com>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: Pekka Paalanen <pekka.paalanen@collabora.com>
Cc: Rob Clark <robdclark@gmail.com>
Cc: Simon Ser <contact@emersion.fr>
Cc: Manasi Navare <navaremanasi@google.com>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Abhinav Kumar <quic_abhinavk@quicinc.com>
Cc: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Signed-off-by: Simona Vetter <simona.vetter@intel.com>
Signed-off-by: Simona Vetter <simona.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20250108172417.160831-1-simona.vetter@ffwll.ch
Signed-off-by: Sasha Levin <sashal@kernel.org>
rcu: fix header guard for rcu_all_qs() 2025-06-04T12:32:34+00:00 Ankur Arora ankur.a.arora@oracle.com 2024-12-13T04:06:52+00:00 55fbc3c00256540b211d4ea2455e21e9b1194b78 [ Upstream commit ad6b5b73ff565e88aca7a7d1286788d80c97ba71 ] rcu_all_qs() is defined for !CONFIG_PREEMPT_RCU but the declaration is conditioned on CONFIG_PREEMPTION. With CONFIG_PREEMPT_LAZY, CONFIG_PREEMPTION=y does not imply CONFIG_PREEMPT_RCU=y. Decouple the two. Cc: Paul E. McKenney <paulmck@kernel.org> Reviewed-by: Frederic Weisbecker <frederic@kernel.org> Reviewed-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Ankur Arora <ankur.a.arora@oracle.com> Signed-off-by: Paul E. McKenney <paulmck@kernel.org> Signed-off-by: Boqun Feng <boqun.feng@gmail.com> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit ad6b5b73ff565e88aca7a7d1286788d80c97ba71 ]

rcu_all_qs() is defined for !CONFIG_PREEMPT_RCU but the declaration
is conditioned on CONFIG_PREEMPTION.

With CONFIG_PREEMPT_LAZY, CONFIG_PREEMPTION=y does not imply
CONFIG_PREEMPT_RCU=y.

Decouple the two.

Cc: Paul E. McKenney <paulmck@kernel.org>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Reviewed-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Ankur Arora <ankur.a.arora@oracle.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Boqun Feng <boqun.feng@gmail.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
net/mlx4_core: Avoid impossible mlx4_db_alloc() order value 2025-06-04T12:32:33+00:00 Kees Cook kees@kernel.org 2025-02-10T17:45:05+00:00 ebe4325f2b52e8c0a760ac0bab53900e549b93f7 [ Upstream commit 4a6f18f28627e121bd1f74b5fcc9f945d6dbeb1e ] GCC can see that the value range for "order" is capped, but this leads it to consider that it might be negative, leading to a false positive warning (with GCC 15 with -Warray-bounds -fdiagnostics-details): ../drivers/net/ethernet/mellanox/mlx4/alloc.c:691:47: error: array subscript -1 is below array bounds of 'long unsigned int *[2]' [-Werror=array-bounds=] 691 | i = find_first_bit(pgdir->bits[o], MLX4_DB_PER_PAGE >> o); | ~~~~~~~~~~~^~~ 'mlx4_alloc_db_from_pgdir': events 1-2 691 | i = find_first_bit(pgdir->bits[o], MLX4_DB_PER_PAGE >> o); | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ | | | | | (2) out of array bounds here | (1) when the condition is evaluated to true In file included from ../drivers/net/ethernet/mellanox/mlx4/mlx4.h:53, from ../drivers/net/ethernet/mellanox/mlx4/alloc.c:42: ../include/linux/mlx4/device.h:664:33: note: while referencing 'bits' 664 | unsigned long *bits[2]; | ^~~~ Switch the argument to unsigned int, which removes the compiler needing to consider negative values. Signed-off-by: Kees Cook <kees@kernel.org> Link: https://patch.msgid.link/20250210174504.work.075-kees@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit 4a6f18f28627e121bd1f74b5fcc9f945d6dbeb1e ]

GCC can see that the value range for "order" is capped, but this leads
it to consider that it might be negative, leading to a false positive
warning (with GCC 15 with -Warray-bounds -fdiagnostics-details):

../drivers/net/ethernet/mellanox/mlx4/alloc.c:691:47: error: array subscript -1 is below array bounds of 'long unsigned int *[2]' [-Werror=array-bounds=]
  691 |                 i = find_first_bit(pgdir->bits[o], MLX4_DB_PER_PAGE >> o);
      |                                    ~~~~~~~~~~~^~~
  'mlx4_alloc_db_from_pgdir': events 1-2
  691 |                 i = find_first_bit(pgdir->bits[o], MLX4_DB_PER_PAGE >> o);                        |                     ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
      |                     |                         |                                                   |                     |                         (2) out of array bounds here
      |                     (1) when the condition is evaluated to true                             In file included from ../drivers/net/ethernet/mellanox/mlx4/mlx4.h:53,
                 from ../drivers/net/ethernet/mellanox/mlx4/alloc.c:42:
../include/linux/mlx4/device.h:664:33: note: while referencing 'bits'
  664 |         unsigned long          *bits[2];
      |                                 ^~~~

Switch the argument to unsigned int, which removes the compiler needing
to consider negative values.

Signed-off-by: Kees Cook <kees@kernel.org>
Link: https://patch.msgid.link/20250210174504.work.075-kees@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>