Currently only the drivers that implement shaper or queue APIs
are grabbing instance lock. Add an explicit opt-in for the
drivers that want to grab the lock without implementing the above
APIs.
There is a 3-byte hole after @up, use it:
/* --- cacheline 47 boundary (3008 bytes) --- */
u32 napi_defer_hard_irqs; /* 3008 4 */
bool up; /* 3012 1 */
/* XXX 3 bytes hole, try to pack */
struct mutex lock; /* 3016 144 */
/* XXX last struct has 1 hole */
Cc: Saeed Mahameed <saeed@kernel.org>
Signed-off-by: Stanislav Fomichev <sdf@fomichev.me>
Link: https://patch.msgid.link/20250305163732.2766420-13-sdf@fomichev.me
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Protect all ethtool callbacks and PHY related state with the netdev
instance lock, for drivers which want / need to have their ops
instance-locked. Basically take the lock everywhere we take rtnl_lock.
It was tempting to take the lock in ethnl_ops_begin(), but turns
out we actually nest those calls (when generating notifications).
Tested-by: Maxime Chevallier <maxime.chevallier@bootlin.com>
Cc: Saeed Mahameed <saeed@kernel.org>
Signed-off-by: Stanislav Fomichev <sdf@fomichev.me>
Link: https://patch.msgid.link/20250305163732.2766420-11-sdf@fomichev.me
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
To preserve the atomicity, hold the lock while applying multiple
attributes. The major issue with a full conversion to the instance
lock are software nesting devices (bonding/team/vrf/etc). Those
devices call into the core stack for their lower (potentially
real hw) devices. To avoid explicitly wrapping all those places
into instance lock/unlock, introduce new API boundaries:
- (some) existing dev_xxx calls are now considered "external"
(to drivers) APIs and they transparently grab the instance
lock if needed (dev_api.c)
- new netif_xxx calls are internal core stack API (naming is
sketchy, I've tried netdev_xxx_locked per Jakub's suggestion,
but it feels a bit verbose; but happy to get back to this
naming scheme if this is the preference)
This avoids touching most of the existing ioctl/sysfs/drivers paths.
Note the special handling of ndo_xxx_slave operations: I exploit
the fact that none of the drivers that call these functions
need/use instance lock. At the same time, they use dev_xxx
APIs, so the lower device has to be unlocked.
Changes in unregister_netdevice_many_notify (to protect dev->state
with instance lock) trigger lockdep - the loop over close_list
(mostly from cleanup_net) introduces spurious ordering issues.
netdev_lock_cmp_fn has a justification on why it's ok to suppress
for now.
Cc: Saeed Mahameed <saeed@kernel.org>
Signed-off-by: Stanislav Fomichev <sdf@fomichev.me>
Link: https://patch.msgid.link/20250305163732.2766420-7-sdf@fomichev.me
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
For the drivers that use queue management API, switch to the mode where
core stack holds the netdev instance lock. This affects the following
drivers:
- bnxt
- gve
- netdevsim
Originally I locked only start/stop, but switched to holding the
lock over all iterations to make them look atomic to the device
(feels like it should be easier to reason about).
Reviewed-by: Eric Dumazet <edumazet@google.com>
Cc: Saeed Mahameed <saeed@kernel.org>
Signed-off-by: Stanislav Fomichev <sdf@fomichev.me>
Link: https://patch.msgid.link/20250305163732.2766420-6-sdf@fomichev.me
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
For the drivers that use shaper API, switch to the mode where
core stack holds the netdev lock. This affects two drivers:
* iavf - already grabs netdev lock in ndo_open/ndo_stop, so mostly
remove these
* netdevsim - switch to _locked APIs to avoid deadlock
iavf_close diff is a bit confusing, the existing call looks like this:
iavf_close() {
netdev_lock()
..
netdev_unlock()
wait_event_timeout(down_waitqueue)
}
I change it to the following:
netdev_lock()
iavf_close() {
..
netdev_unlock()
wait_event_timeout(down_waitqueue)
netdev_lock() // reusing this lock call
}
netdev_unlock()
Since I'm reusing existing netdev_lock call, so it looks like I only
add netdev_unlock.
Cc: Saeed Mahameed <saeed@kernel.org>
Signed-off-by: Stanislav Fomichev <sdf@fomichev.me>
Link: https://patch.msgid.link/20250305163732.2766420-2-sdf@fomichev.me
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
After blamed commit rtm_to_fib_config() now calls
lwtunnel_valid_encap_type{_attr}() without RTNL held,
triggering an unlock balance in __rtnl_unlock,
as reported by syzbot [1]
IPv6 and rtm_to_nh_config() are not yet converted.
Add a temporary @rtnl_is_held parameter to lwtunnel_valid_encap_type()
and lwtunnel_valid_encap_type_attr().
While we are at it replace the two rcu_dereference()
in lwtunnel_valid_encap_type() with more appropriate
rcu_access_pointer().
[1]
syz-executor245/5836 is trying to release lock (rtnl_mutex) at:
[<ffffffff89d0e38c>] __rtnl_unlock+0x6c/0xf0 net/core/rtnetlink.c:142
but there are no more locks to release!
other info that might help us debug this:
no locks held by syz-executor245/5836.
stack backtrace:
CPU: 0 UID: 0 PID: 5836 Comm: syz-executor245 Not tainted 6.14.0-rc4-syzkaller-00873-g3424291dd242 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120
print_unlock_imbalance_bug+0x25b/0x2d0 kernel/locking/lockdep.c:5289
__lock_release kernel/locking/lockdep.c:5518 [inline]
lock_release+0x47e/0xa30 kernel/locking/lockdep.c:5872
__mutex_unlock_slowpath+0xec/0x800 kernel/locking/mutex.c:891
__rtnl_unlock+0x6c/0xf0 net/core/rtnetlink.c:142
lwtunnel_valid_encap_type+0x38a/0x5f0 net/core/lwtunnel.c:169
lwtunnel_valid_encap_type_attr+0x113/0x270 net/core/lwtunnel.c:209
rtm_to_fib_config+0x949/0x14e0 net/ipv4/fib_frontend.c:808
inet_rtm_newroute+0xf6/0x2a0 net/ipv4/fib_frontend.c:917
rtnetlink_rcv_msg+0x791/0xcf0 net/core/rtnetlink.c:6919
netlink_rcv_skb+0x206/0x480 net/netlink/af_netlink.c:2534
netlink_unicast_kernel net/netlink/af_netlink.c:1313 [inline]
netlink_unicast+0x7f6/0x990 net/netlink/af_netlink.c:1339
netlink_sendmsg+0x8de/0xcb0 net/netlink/af_netlink.c:1883
sock_sendmsg_nosec net/socket.c:709 [inline]
Fixes: 1dd2af7963 ("ipv4: fib: Convert RTM_NEWROUTE and RTM_DELROUTE to per-netns RTNL.")
Reported-by: syzbot+3f18ef0f7df107a3f6a0@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/netdev/67c6f87a.050a0220.38b91b.0147.GAE@google.com/T/#u
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Link: https://patch.msgid.link/20250304125918.2763514-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Heiner Kallweit says:
====================
net: phy: move PHY package code to its own source file
This series contributes to cleaning up phylib by moving PHY package
related code to its own source file.
====================
Link: https://patch.msgid.link/5c5e60b3-0378-4960-8cf0-07ce0e219c68@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Choong Yong Liang says:
====================
Enable SGMII and 2500BASEX interface mode switching for Intel platforms
During the interface mode change, the 'phylink_major_config' function will
be triggered in phylink. The modification of the following functions will
support the switching between SGMII and 2500BASE-X interface modes for
the Intel platform:
- xpcs_switch_interface_mode: Re-initiates clause 37 auto-negotiation for
the SGMII interface mode to perform auto-negotiation.
- mac_finish: Configures the SerDes according to the interface mode.
With the above changes, the code will work as follows during the interface
mode change. The PCS will reconfigure according to the pcs_neg_mode and the
selected interface mode. Then, the MAC driver will perform SerDes
configuration in 'mac_finish' based on the selected interface mode. During
the SerDes configuration, the selected interface mode will identify TSN
lane registers from FIA and then send IPC commands to the Power Management
Controller (PMC) through the PMC driver/API. The PMC will act as a proxy to
program the PLL registers.
====================
Link: https://patch.msgid.link/20250227121522.1802832-1-yong.liang.choong@linux.intel.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Intel platform will configure the SerDes through PMC API based on the
provided interface mode.
This patch adds several new functions below:-
- intel_tsn_lane_is_available(): This new function reads FIA lane
ownership registers and common lane registers through IPC commands
to know which lane the mGbE port is assigned to.
- intel_mac_finish(): To configure the SerDes based on the assigned
lane and latest interface mode, it sends IPC command to the PMC through
PMC driver/API. The PMC acts as a proxy for R/W on behalf of the driver.
- intel_set_reg_access(): Set the register access to the available TSN
interface.
Signed-off-by: Choong Yong Liang <yong.liang.choong@linux.intel.com>
Link: https://patch.msgid.link/20250227121522.1802832-6-yong.liang.choong@linux.intel.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
The xpcs_switch_interface_mode function was introduced to handle
interface switching.
According to the XPCS datasheet, a soft reset is required to initiate
Clause 37 auto-negotiation when the XPCS switches interface modes.
When the interface mode switches from 2500BASE-X to SGMII,
re-initiating Clause 37 auto-negotiation is required for the SGMII
interface mode to function properly.
Signed-off-by: Choong Yong Liang <yong.liang.choong@linux.intel.com>
Link: https://patch.msgid.link/20250227121522.1802832-3-yong.liang.choong@linux.intel.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
The phylink_expects_phy() function allows MAC drivers to check if they are
expecting a PHY to attach. The checking condition in phylink_expects_phy()
aims to achieve the same result as the checking condition in
phylink_attach_phy().
However, the checking condition in phylink_expects_phy() uses
pl->link_config.interface, while phylink_attach_phy() uses
pl->link_interface.
Initially, both pl->link_interface and pl->link_config.interface are set
to SGMII, and pl->cfg_link_an_mode is set to MLO_AN_INBAND.
When the interface switches from SGMII to 2500BASE-X,
pl->link_config.interface is updated by phylink_major_config().
At this point, pl->cfg_link_an_mode remains MLO_AN_INBAND, and
pl->link_config.interface is set to 2500BASE-X.
Subsequently, when the STMMAC interface is taken down
administratively and brought back up, it is blocked by
phylink_expects_phy().
Since phylink_expects_phy() and phylink_attach_phy() aim to achieve the
same result, phylink_expects_phy() should check pl->link_interface,
which never changes, instead of pl->link_config.interface, which is
updated by phylink_major_config().
Reviewed-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Signed-off-by: Choong Yong Liang <yong.liang.choong@linux.intel.com>
Link: https://patch.msgid.link/20250227121522.1802832-2-yong.liang.choong@linux.intel.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Wojtek Wasko says:
====================
Permission checks for dynamic POSIX clocks
Dynamic clocks - such as PTP clocks - extend beyond the standard POSIX
clock API by using ioctl calls. While file permissions are enforced for
standard POSIX operations, they are not implemented for ioctl calls,
since the POSIX layer cannot differentiate between calls which modify
the clock's state (like enabling PPS output generation) and those that
don't (such as retrieving the clock's PPS capabilities).
On the other hand, drivers implementing the dynamic clocks lack the
necessary information context to enforce permission checks themselves.
Additionally, POSIX clock layer requires the WRITE permission even for
readonly adjtime() operations before invoking the callback.
Add a struct file pointer to the POSIX clock context and use it to
implement the appropriate permission checks on PTP chardevs. Permit
readonly adjtime() for dynamic clocks. Add a readonly option to testptp.
Changes in v4:
- Allow readonly adjtime() for dynamic clocks, as suggested by Thomas
Changes in v3:
- Reword the log message for commit against posix-clock and fix
documentation of struct posix_clock_context, as suggested by Thomas
Changes in v2:
- Store file pointer in POSIX clock context rather than fmode in the PTP
clock's private data, as suggested by Richard.
- Move testptp.c changes into separate patch.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
PTP Hardware Clocks no longer require WRITE permission to perform
readonly operations, such as listing device capabilities or listening to
EXTTS events once they have been enabled by a process with WRITE
permissions.
Add '-r' option to testptp to open the PHC in readonly mode instead of
the default read-write mode. Skip enabling EXTTS if readonly mode is
requested.
Acked-by: Richard Cochran <richardcochran@gmail.com>
Reviewed-by: Vadim Fedorenko <vadim.fedorenko@linux.dev>
Signed-off-by: Wojtek Wasko <wwasko@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Many devices implement highly accurate clocks, which the kernel manages
as PTP Hardware Clocks (PHCs). Userspace applications rely on these
clocks to timestamp events, trace workload execution, correlate
timescales across devices, and keep various clocks in sync.
The kernel’s current implementation of PTP clocks does not enforce file
permissions checks for most device operations except for POSIX clock
operations, where file mode is verified in the POSIX layer before
forwarding the call to the PTP subsystem. Consequently, it is common
practice to not give unprivileged userspace applications any access to
PTP clocks whatsoever by giving the PTP chardevs 600 permissions. An
example of users running into this limitation is documented in [1].
Additionally, POSIX layer requires WRITE permission even for readonly
adjtime() calls which are used in PTP layer to return current frequency
offset applied to the PHC.
Add permission checks for functions that modify the state of a PTP
device. Continue enforcing permission checks for POSIX clock operations
(settime, adjtime) in the POSIX layer. Only require WRITE access for
dynamic clocks adjtime() if any flags are set in the modes field.
[1] https://lists.nwtime.org/sympa/arc/linuxptp-users/2024-01/msg00036.html
Changes in v4:
- Require FMODE_WRITE in ajtime() only for calls modifying the clock in
any way.
Acked-by: Richard Cochran <richardcochran@gmail.com>
Reviewed-by: Vadim Fedorenko <vadim.fedorenko@linux.dev>
Signed-off-by: Wojtek Wasko <wwasko@nvidia.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
File descriptor based pc_clock_*() operations of dynamic posix clocks
have access to the file pointer and implement permission checks in the
generic code before invoking the relevant dynamic clock callback.
Character device operations (open, read, poll, ioctl) do not implement a
generic permission control and the dynamic clock callbacks have no
access to the file pointer to implement them.
Extend struct posix_clock_context with a struct file pointer and
initialize it in posix_clock_open(), so that all dynamic clock callbacks
can access it.
Acked-by: Richard Cochran <richardcochran@gmail.com>
Reviewed-by: Vadim Fedorenko <vadim.fedorenko@linux.dev>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Wojtek Wasko <wwasko@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The new stats calculations add several additional calls to
macb/gem_update_stats() and accesses to bp->hw_stats. These are
protected by a spinlock since commit fa52f15c74 ("net: cadence: macb:
Synchronize stats calculations"), which was applied in parallel. Add
some locking now that the net has been merged into net-next.
Fixes: f6af690a29 ("net: cadence: macb: Report standard stats")
Signed-off-by: Sean Anderson <sean.anderson@linux.dev>
Link: https://patch.msgid.link/20250303231832.1648274-1-sean.anderson@linux.dev
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Eric Dumazet says:
====================
tcp: scale connect() under pressure
Adoption of bhash2 in linux-6.1 made some operations almost twice
more expensive, because of additional locks.
This series adds RCU in __inet_hash_connect() to help the
case where many attempts need to be made before finding
an available 4-tuple.
This brings a ~200 % improvement in this experiment:
Server:
ulimit -n 40000; neper/tcp_crr -T 200 -F 30000 -6 --nolog
Client:
ulimit -n 40000; neper/tcp_crr -T 200 -F 30000 -6 --nolog -c -H server
Before series:
utime_start=0.288582
utime_end=1.548707
stime_start=20.637138
stime_end=2002.489845
num_transactions=484453
latency_min=0.156279245
latency_max=20.922042756
latency_mean=1.546521274
latency_stddev=3.936005194
num_samples=312537
throughput=47426.00
perf top on the client:
49.54% [kernel] [k] _raw_spin_lock
25.87% [kernel] [k] _raw_spin_lock_bh
5.97% [kernel] [k] queued_spin_lock_slowpath
5.67% [kernel] [k] __inet_hash_connect
3.53% [kernel] [k] __inet6_check_established
3.48% [kernel] [k] inet6_ehashfn
0.64% [kernel] [k] rcu_all_qs
After this series:
utime_start=0.271607
utime_end=3.847111
stime_start=18.407684
stime_end=1997.485557
num_transactions=1350742
latency_min=0.014131929
latency_max=17.895073144
latency_mean=0.505675853 # Nice reduction of latency metrics
latency_stddev=2.125164772
num_samples=307884
throughput=139866.80 # 194 % increase
perf top on client:
56.86% [kernel] [k] __inet6_check_established
17.96% [kernel] [k] __inet_hash_connect
13.88% [kernel] [k] inet6_ehashfn
2.52% [kernel] [k] rcu_all_qs
2.01% [kernel] [k] __cond_resched
0.41% [kernel] [k] _raw_spin_lock
====================
Link: https://patch.msgid.link/20250302124237.3913746-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
When __inet_hash_connect() has to try many 4-tuples before
finding an available one, we see a high spinlock cost from
the many spin_lock_bh(&head->lock) performed in its loop.
This patch adds an RCU lookup to avoid the spinlock cost.
check_established() gets a new @rcu_lookup argument.
First reason is to not make any changes while head->lock
is not held.
Second reason is to not make this RCU lookup a second time
after the spinlock has been acquired.
Tested:
Server:
ulimit -n 40000; neper/tcp_crr -T 200 -F 30000 -6 --nolog
Client:
ulimit -n 40000; neper/tcp_crr -T 200 -F 30000 -6 --nolog -c -H server
Before series:
utime_start=0.288582
utime_end=1.548707
stime_start=20.637138
stime_end=2002.489845
num_transactions=484453
latency_min=0.156279245
latency_max=20.922042756
latency_mean=1.546521274
latency_stddev=3.936005194
num_samples=312537
throughput=47426.00
perf top on the client:
49.54% [kernel] [k] _raw_spin_lock
25.87% [kernel] [k] _raw_spin_lock_bh
5.97% [kernel] [k] queued_spin_lock_slowpath
5.67% [kernel] [k] __inet_hash_connect
3.53% [kernel] [k] __inet6_check_established
3.48% [kernel] [k] inet6_ehashfn
0.64% [kernel] [k] rcu_all_qs
After this series:
utime_start=0.271607
utime_end=3.847111
stime_start=18.407684
stime_end=1997.485557
num_transactions=1350742
latency_min=0.014131929
latency_max=17.895073144
latency_mean=0.505675853 # Nice reduction of latency metrics
latency_stddev=2.125164772
num_samples=307884
throughput=139866.80 # 190 % increase
perf top on client:
56.86% [kernel] [k] __inet6_check_established
17.96% [kernel] [k] __inet_hash_connect
13.88% [kernel] [k] inet6_ehashfn
2.52% [kernel] [k] rcu_all_qs
2.01% [kernel] [k] __cond_resched
0.41% [kernel] [k] _raw_spin_lock
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Jason Xing <kerneljasonxing@gmail.com>
Tested-by: Jason Xing <kerneljasonxing@gmail.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Link: https://patch.msgid.link/20250302124237.3913746-5-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
When __inet_hash_connect() has to try many 4-tuples before
finding an available one, we see a high spinlock cost from
__inet_check_established() and/or __inet6_check_established().
This patch adds an RCU lookup to avoid the spinlock
acquisition when the 4-tuple is found in the hash table.
Note that there are still spin_lock_bh() calls in
__inet_hash_connect() to protect inet_bind_hashbucket,
this will be fixed later in this series.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Jason Xing <kerneljasonxing@gmail.com>
Tested-by: Jason Xing <kerneljasonxing@gmail.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Link: https://patch.msgid.link/20250302124237.3913746-2-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
The address of a data structure member was determined before
a corresponding null pointer check in the implementation of
the function “tipc_link_tnl_prepare”.
Thus avoid the risk for undefined behaviour by moving the definition
for the local variable “fdefq” into an if branch at the end.
This issue was detected by using the Coccinelle software.
Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Link: https://patch.msgid.link/08fe8fc3-19c3-4324-8719-0ee74b0f32c9@web.de
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Commit 29b036be1b ("selftests: drv-net: test XDP, HDS auto and
the ioctl path") added a new test case in the net tree, now that
this code has made its way to net-next convert it to use the env.rpath()
helper instead of manually computing the relative path.
Acked-by: Stanislav Fomichev <sdf@fomichev.me>
Link: https://patch.msgid.link/20250228212956.25399-1-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
For PPPoE, PPTP, and PPPoL2TP, the start_xmit() function directly
forwards packets to the underlying network stack and never returns
anything other than 1. So these interfaces do not require a qdisc,
and the IFF_NO_QUEUE flag should be set.
Introduces a direct_xmit flag in struct ppp_channel to indicate when
IFF_NO_QUEUE should be applied. The flag is set in ppp_connect_channel()
for relevant protocols.
While at it, remove the usused latency member from struct ppp_channel.
Signed-off-by: Qingfang Deng <dqfext@gmail.com>
Reviewed-by: Toke Høiland-Jørgensen <toke@redhat.com>
Link: https://patch.msgid.link/20250301135517.695809-1-dqfext@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Lee Trager says:
====================
eth: fbnic: Cleanup macros and string function
We have received some feedback that the macros we use for reading FW mailbox
attributes are too large in scope and confusing to understanding. Additionally
the string function did not provide errors allowing it to silently succeed.
This patch set fixes theses issues.
====================
Link: https://patch.msgid.link/20250228191935.3953712-1-lee@trager.us
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Replace the firmware field macros with new macros which follow typical
kernel standards. No variables are required to be predefined for use and
results are now returned. These macros are prefixed with fta or fbnic
TLV attribute.
Signed-off-by: Lee Trager <lee@trager.us>
Link: https://patch.msgid.link/20250228191935.3953712-4-lee@trager.us
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Allow fbnic_tlv_attr_get_string() to return an error code. In the event the
source mailbox attribute is missing return -EINVAL. Like nla_strscpy() return
-E2BIG when the source string is larger than the destination string. In this
case the amount of data copied is equal to dstsize.
Signed-off-by: Lee Trager <lee@trager.us>
Link: https://patch.msgid.link/20250228191935.3953712-3-lee@trager.us
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
