linux-stable.git/net, branch v5.4.301

net: rtnetlink: fix module reference count leak issue in rtnetlink_rcv_msg

2025-10-29T13:00:01+00:00

commit 5b22f62724a0a09e00d301abf5b57b0c12be8a16 upstream.

When bulk delete command is received in the rtnetlink_rcv_msg function,
if bulk delete is not supported, module_put is not called to release
the reference counting. As a result, module reference count is leaked.

Fixes: a6cec0bcd342 ("net: rtnetlink: add bulk delete support flag")
Signed-off-by: Zhengchao Shao 
Acked-by: Nikolay Aleksandrov 
Link: https://lore.kernel.org/r/20220815024629.240367-1-shaozhengchao@huawei.com
Signed-off-by: Jakub Kicinski 
Signed-off-by: Greg Kroah-Hartman

sctp: avoid NULL dereference when chunk data buffer is missing

2025-10-29T12:59:59+00:00

[ Upstream commit 441f0647f7673e0e64d4910ef61a5fb8f16bfb82 ]

chunk->skb pointer is dereferenced in the if-block where it's supposed
to be NULL only.

chunk->skb can only be NULL if chunk->head_skb is not. Check for frag_list
instead and do it just before replacing chunk->skb. We're sure that
otherwise chunk->skb is non-NULL because of outer if() condition.

Fixes: 90017accff61 ("sctp: Add GSO support")
Signed-off-by: Alexey Simakov 
Acked-by: Marcelo Ricardo Leitner 
Link: https://patch.msgid.link/20251021130034.6333-1-bigalex934@gmail.com
Signed-off-by: Jakub Kicinski 
Signed-off-by: Sasha Levin

rtnetlink: Allow deleting FDB entries in user namespace

2025-10-29T12:59:59+00:00

[ Upstream commit bf29555f5bdc017bac22ca66fcb6c9f46ec8788f ]

Creating FDB entries is possible from a non-initial user namespace when
having CAP_NET_ADMIN, yet, when deleting FDB entries, processes receive
an EPERM because the capability is always checked against the initial
user namespace. This restricts the FDB management from unprivileged
containers.

Drop the netlink_capable check in rtnl_fdb_del as it was originally
dropped in c5c351088ae7 and reintroduced in 1690be63a27b without
intention.

This patch was tested using a container on GyroidOS, where it was
possible to delete FDB entries from an unprivileged user namespace and
private network namespace.

Fixes: 1690be63a27b ("bridge: Add vlan support to static neighbors")
Reviewed-by: Michael Weiß 
Tested-by: Harshal Gohel 
Signed-off-by: Johannes Wiesböck 
Reviewed-by: Ido Schimmel 
Reviewed-by: Nikolay Aleksandrov 
Link: https://patch.msgid.link/20251015201548.319871-1-johannes.wiesboeck@aisec.fraunhofer.de
Signed-off-by: Jakub Kicinski 
Signed-off-by: Sasha Levin

net: rtnetlink: add NLM_F_BULK support to rtnl_fdb_del

2025-10-29T12:59:59+00:00

[ Upstream commit 9e83425993f38bb89e0ea07849ba0039a748e85b ]

When NLM_F_BULK is specified in a fdb del message we need to handle it
differently. First since this is a new call we can strictly validate the
passed attributes, at first only ifindex and vlan are allowed as these
will be the initially supported filter attributes, any other attribute
is rejected. The mac address is no longer mandatory, but we use it
to error out in older kernels because it cannot be specified with bulk
request (the attribute is not allowed) and then we have to dispatch
the call to ndo_fdb_del_bulk if the device supports it. The del bulk
callback can do further validation of the attributes if necessary.

Signed-off-by: Nikolay Aleksandrov 
Signed-off-by: David S. Miller 
Stable-dep-of: bf29555f5bdc ("rtnetlink: Allow deleting FDB entries in user namespace")
Signed-off-by: Sasha Levin

net: rtnetlink: add bulk delete support flag

2025-10-29T12:59:59+00:00

[ Upstream commit a6cec0bcd34264be8887791594be793b3f12719f ]

Add a new rtnl flag (RTNL_FLAG_BULK_DEL_SUPPORTED) which is used to
verify that the delete operation allows bulk object deletion. Also emit
a warning if anyone tries to set it for non-delete kind.

Suggested-by: David Ahern 
Signed-off-by: Nikolay Aleksandrov 
Signed-off-by: David S. Miller 
Stable-dep-of: bf29555f5bdc ("rtnetlink: Allow deleting FDB entries in user namespace")
Signed-off-by: Sasha Levin

net: rtnetlink: add helper to extract msg type's kind

2025-10-29T12:59:58+00:00

[ Upstream commit 2e9ea3e30f696fd438319c07836422bb0bbb4608 ]

Add a helper which extracts the msg type's kind using the kind mask (0x3).

Signed-off-by: Nikolay Aleksandrov 
Signed-off-by: David S. Miller 
Stable-dep-of: bf29555f5bdc ("rtnetlink: Allow deleting FDB entries in user namespace")
Signed-off-by: Sasha Levin

net: rtnetlink: add msg kind names

2025-10-29T12:59:58+00:00

[ Upstream commit 12dc5c2cb7b269c5a1c6d02844f40bfce942a7a6 ]

Add rtnl kind names instead of using raw values. We'll need to
check for DEL kind later to validate bulk flag support.

Signed-off-by: Nikolay Aleksandrov 
Signed-off-by: David S. Miller 
Stable-dep-of: bf29555f5bdc ("rtnetlink: Allow deleting FDB entries in user namespace")
Signed-off-by: Sasha Levin

net: rtnetlink: remove redundant assignment to variable err

2025-10-29T12:59:58+00:00

[ Upstream commit 7d3118016787b5c05da94b3bcdb96c9d6ff82c44 ]

The variable err is being initializeed with a value that is never read
and it is being updated later with a new value. The initialization
is redundant and can be removed.

Addresses-Coverity: ("Unused value")
Signed-off-by: Colin Ian King 
Signed-off-by: David S. Miller 
Stable-dep-of: bf29555f5bdc ("rtnetlink: Allow deleting FDB entries in user namespace")
Signed-off-by: Sasha Levin

tls: don't rely on tx_work during send()

2025-10-29T12:59:57+00:00

[ Upstream commit 7f846c65ca11e63d2409868ff039081f80e42ae4 ]

With async crypto, we rely on tx_work to actually transmit records
once encryption completes. But while send() is running, both the
tx_lock and socket lock are held, so tx_work_handler cannot process
the queue of encrypted records, and simply reschedules itself. During
a large send(), this could last a long time, and use a lot of memory.

Transmit any pending encrypted records before restarting the main
loop of tls_sw_sendmsg_locked.

Fixes: a42055e8d2c3 ("net/tls: Add support for async encryption of records for performance")
Reported-by: Jann Horn 
Signed-off-by: Sabrina Dubroca 
Link: https://patch.msgid.link/8396631478f70454b44afb98352237d33f48d34d.1760432043.git.sd@queasysnail.net
Signed-off-by: Jakub Kicinski 
Signed-off-by: Sasha Levin

tls: always set record_type in tls_process_cmsg

2025-10-29T12:59:57+00:00

[ Upstream commit b6fe4c29bb51cf239ecf48eacf72b924565cb619 ]

When userspace wants to send a non-DATA record (via the
TLS_SET_RECORD_TYPE cmsg), we need to send any pending data from a
previous MSG_MORE send() as a separate DATA record. If that DATA record
is encrypted asynchronously, tls_handle_open_record will return
-EINPROGRESS. This is currently treated as an error by
tls_process_cmsg, and it will skip setting record_type to the correct
value, but the caller (tls_sw_sendmsg_locked) handles that return
value correctly and proceeds with sending the new message with an
incorrect record_type (DATA instead of whatever was requested in the
cmsg).

Always set record_type before handling the open record. If
tls_handle_open_record returns an error, record_type will be
ignored. If it succeeds, whether with synchronous crypto (returning 0)
or asynchronous (returning -EINPROGRESS), the caller will proceed
correctly.

Fixes: a42055e8d2c3 ("net/tls: Add support for async encryption of records for performance")
Reported-by: Jann Horn 
Signed-off-by: Sabrina Dubroca 
Link: https://patch.msgid.link/0457252e578a10a94e40c72ba6288b3a64f31662.1760432043.git.sd@queasysnail.net
Signed-off-by: Jakub Kicinski 
Signed-off-by: Sasha Levin