linux-stable.git, branch v6.12.91

Linux 6.12.91

2026-05-23T11:05:02+00:00

Link: https://lore.kernel.org/r/20260520162111.222830634@linuxfoundation.org
Tested-by: Brett A C Sheffield 
Tested-by: Francesco Dolcini 
Tested-by: Pavel Machek (CIP) 
Tested-by: Mark Brown 
Signed-off-by: Greg Kroah-Hartman

netfs: Fix potential uninitialised var in netfs_extract_user_iter()

2026-05-23T11:05:02+00:00

commit 7e3d8db899d54af39fafb2eb3392b0cdae9973b5 upstream.

In netfs_extract_user_iter(), if it's given a zero-length iterator, it will
fall through the loop without setting ret, and so the error handling
behaviour will be undefined, depending on whether ret happens to be
negative.  The value of ret then propagates back up the callstack.

Fix this by presetting ret to 0.

Fixes: 85dd2c8ff368 ("netfs: Add a function to extract a UBUF or IOVEC into a BVEC iterator")
Closes: https://sashiko.dev/#/patchset/20260414082004.3756080-1-dhowells%40redhat.com
Signed-off-by: David Howells 
Link: https://patch.msgid.link/20260512123404.719402-9-dhowells@redhat.com
cc: Paulo Alcantara 
cc: Matthew Wilcox 
cc: netfs@lists.linux.dev
cc: linux-fsdevel@vger.kernel.org
Signed-off-by: Christian Brauner 
Signed-off-by: Greg Kroah-Hartman

net: skbuff: propagate shared-frag marker through frag-transfer helpers

2026-05-23T11:05:02+00:00

commit 48f6a5356a33dd78e7144ae1faef95ffc990aae0 upstream.

Two frag-transfer helpers (__pskb_copy_fclone() and skb_shift()) fail
to propagate the SKBFL_SHARED_FRAG bit in skb_shinfo()->flags when
moving frags from source to destination.  __pskb_copy_fclone() defers
the rest of the shinfo metadata to skb_copy_header() after copying
frag descriptors, but that helper only carries over gso_{size,segs,
type} and never touches skb_shinfo()->flags; skb_shift() moves frag
descriptors directly and leaves flags untouched.  As a result, the
destination skb keeps a reference to the same externally-owned or
page-cache-backed pages while reporting skb_has_shared_frag() as
false.

The mismatch is harmful in any in-place writer that uses
skb_has_shared_frag() to decide whether shared pages must be detoured
through skb_cow_data().  ESP input is one such writer (esp4.c,
esp6.c), and a single nft 'dup to ' rule -- or any other
nf_dup_ipv4() / xt_TEE caller -- is enough to land a pskb_copy()'d
skb in esp_input() with the marker stripped, letting an unprivileged
user write into the page cache of a root-owned read-only file via
authencesn-ESN stray writes.

Set SKBFL_SHARED_FRAG on the destination whenever frag descriptors
were actually moved from the source.  skb_copy() and skb_copy_expand()
share skb_copy_header() too but linearize all paged data into freshly
allocated head storage and emerge with nr_frags == 0, so
skb_has_shared_frag() returns false on its own; they need no change.

The same omission exists in skb_gro_receive() and skb_gro_receive_list().
The former moves the incoming skb's frag descriptors into the
accumulator's last sub-skb via two paths (a direct frag-move loop and
the head_frag + memcpy path); the latter chains the incoming skb whole
onto p's frag_list.  Downstream skb_segment() reads only
skb_shinfo(p)->flags, and skb_segment_list() reuses each sub-skb's
shinfo as the nskb -- both p and lp must carry the marker.

The same omission also exists in tcp_clone_payload(), which builds an
MTU probe skb by moving frag descriptors from skbs on sk_write_queue
into a freshly allocated nskb.  The helper falls into the same family
and warrants the same fix for consistency; no TCP TX-side in-place
writer is currently known to reach a user page through this gap, but
a future consumer depending on the marker would regress silently.

The same omission exists in skb_segment(): the per-iteration flag
merge takes only head_skb's flag, and the inner switch that rebinds
frag_skb to list_skb on head_skb-frags exhaustion does not fold the
new frag_skb's flag into nskb.  Fold frag_skb's flag at both sites
so segments drawing frags from frag_list members carry the marker.

Fixes: cef401de7be8 ("net: fix possible wrong checksum generation")
Fixes: f4c50a4034e6 ("xfrm: esp: avoid in-place decrypt on shared skb frags")
Suggested-by: Sabrina Dubroca 
Suggested-by: Sultan Alsawaf 
Suggested-by: Ben Hutchings 
Suggested-by: Lin Ma 
Suggested-by: Jingguo Tan 
Suggested-by: Aaron Esau 
Cc: stable@vger.kernel.org
Signed-off-by: Hyunwoo Kim 
Tested-by: Rajat Gupta 
Link: https://patch.msgid.link/ageeJfJHwgzmKXbh@v4bel
Signed-off-by: Paolo Abeni 
Signed-off-by: Greg Kroah-Hartman

net: skbuff: preserve shared-frag marker during coalescing

2026-05-23T11:05:02+00:00

commit f84eca5817390257cef78013d0112481c503b4a3 upstream.

skb_try_coalesce() can attach paged frags from @from to @to.  If @from
has SKBFL_SHARED_FRAG set, the resulting @to skb can contain the same
externally-owned or page-cache-backed frags, but the shared-frag marker
is currently lost.

That breaks the invariant relied on by later in-place writers.  In
particular, ESP input checks skb_has_shared_frag() before deciding
whether an uncloned nonlinear skb can skip skb_cow_data().  If TCP
receive coalescing has moved shared frags into an unmarked skb, ESP can
see skb_has_shared_frag() as false and decrypt in place over page-cache
backed frags.

Propagate SKBFL_SHARED_FRAG when skb_try_coalesce() transfers paged
frags.  The tailroom copy path does not need the marker because it copies
bytes into @to's linear data rather than transferring frag descriptors.

Fixes: cef401de7be8 ("net: fix possible wrong checksum generation")
Fixes: f4c50a4034e6 ("xfrm: esp: avoid in-place decrypt on shared skb frags")
Signed-off-by: William Bowling 
Reviewed-by: Eric Dumazet 
Tested-by: Jiayuan Chen 
Link: https://patch.msgid.link/20260513041635.1289541-1-vakzz@zellic.io
Signed-off-by: Jakub Kicinski 
Signed-off-by: Greg Kroah-Hartman

net/rds: reset op_nents when zerocopy page pin fails

2026-05-23T11:05:02+00:00

commit e174929793195e0cd6a4adb0cad731b39f9019b4 upstream.

When iov_iter_get_pages2() fails in rds_message_zcopy_from_user(),
the pinned pages are released with put_page(), and
rm->data.op_mmp_znotifier is cleared.  But we fail to properly
clear rm->data.op_nents.

Later when rds_message_purge() is called from rds_sendmsg() the
cleanup loop iterates over the incorrectly non zero number of
op_nents and frees them again.

Fix this by properly resetting op_nents when it should be in
rds_message_zcopy_from_user().

Fixes: 0cebaccef3ac ("rds: zerocopy Tx support.")
Signed-off-by: Allison Henderson 
Reviewed-by: Simon Horman 
Link: https://patch.msgid.link/20260505234336.2132721-1-achender@kernel.org
Signed-off-by: Jakub Kicinski 
Signed-off-by: Greg Kroah-Hartman

mptcp: pm: ADD_ADDR rtx: resched blocked ADD_ADDR quicker

2026-05-23T11:05:02+00:00

[ Upstream commit 3cf12492891c4b5ff54dda404a2de4ec54c9e1b5 ]

When an ADD_ADDR needs to be retransmitted and another one has already
been prepared -- e.g. multiple ADD_ADDRs have been sent in a row and
need to be retransmitted later -- this additional retransmission will
need to wait.

In this case, the timer was reset to TCP_RTO_MAX / 8, which is ~15
seconds. This delay is unnecessary long: it should just be rescheduled
at the next opportunity, e.g. after the retransmission timeout.

Without this modification, some issues can be seen from time to time in
the selftests when multiple ADD_ADDRs are sent, and the host takes time
to process them, e.g. the "signal addresses, ADD_ADDR timeout" MPTCP
Join selftest, especially with a debug kernel config.

Note that on older kernels, 'timeout' is not available. It should be
enough to replace it by one second (HZ).

Fixes: 00cfd77b9063 ("mptcp: retransmit ADD_ADDR when timeout")
Cc: stable@vger.kernel.org
Reviewed-by: Mat Martineau 
Signed-off-by: Matthieu Baerts (NGI0) 
Link: https://patch.msgid.link/20260505-net-mptcp-pm-fixes-7-1-rc3-v1-6-fca8091060a4@kernel.org
Signed-off-by: Jakub Kicinski 
[ replaced `TCP_RTO_MAX / 8` with `HZ` ]
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

mptcp: pm: ADD_ADDR rtx: fix potential data-race

2026-05-23T11:05:02+00:00

[ Upstream commit 5cd6e0ad79d2615264f63929f8b457ad97ae550d ]

This mptcp_pm_add_timer() helper is executed as a timer callback in
softirq context. To avoid any data races, the socket lock needs to be
held with bh_lock_sock().

If the socket is in use, retry again soon after, similar to what is done
with the keepalive timer.

Fixes: 00cfd77b9063 ("mptcp: retransmit ADD_ADDR when timeout")
Cc: stable@vger.kernel.org
Reviewed-by: Mat Martineau 
Signed-off-by: Matthieu Baerts (NGI0) 
Link: https://patch.msgid.link/20260505-net-mptcp-pm-fixes-7-1-rc3-v1-3-fca8091060a4@kernel.org
Signed-off-by: Jakub Kicinski 
[ applied hunk to `net/mptcp/pm_netlink.c` instead of `net/mptcp/pm.c` ]
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

mptcp: pm: kernel: correctly retransmit ADD_ADDR ID 0

2026-05-23T11:05:02+00:00

[ Upstream commit b12014d2d36eaed4e4bec5f1ac7e91110eeb100d ]

When adding the ADD_ADDR to the list, the address including the IP, port
and ID are copied. On the other hand, when the endpoint corresponds to
the one from the initial subflow, the ID is set to 0, as specified by
the MPTCP protocol.

The issue is that the ID was reset after having copied the ID in the
ADD_ADDR entry. So the retransmission was done, but using a different ID
than the initial one.

Fixes: 8b8ed1b429f8 ("mptcp: pm: reuse ID 0 after delete and re-add")
Cc: stable@vger.kernel.org
Reviewed-by: Mat Martineau 
Signed-off-by: Matthieu Baerts (NGI0) 
Link: https://patch.msgid.link/20260505-net-mptcp-pm-fixes-7-1-rc3-v1-1-fca8091060a4@kernel.org
Signed-off-by: Jakub Kicinski 
[ applied to net/mptcp/pm_netlink.c instead of upstream's pm_kernel.c ]
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

spi: sifive: fix controller deregistration

2026-05-23T11:05:02+00:00

[ Upstream commit 0f25236694a2854627c1597465a071e6bb6fe572 ]

Make sure to deregister the controller before disabling underlying
resources like interrupts during driver unbind.

Note that clocks were also disabled before the recent commit
140039c23aca ("spi: sifive: Simplify clock handling with
devm_clk_get_enabled()").

Fixes: 484a9a68d669 ("spi: sifive: Add driver for the SiFive SPI controller")
Cc: stable@vger.kernel.org	# 5.1
Cc: Yash Shah 
Signed-off-by: Johan Hovold 
Link: https://patch.msgid.link/20260410081757.503099-15-johan@kernel.org
Signed-off-by: Mark Brown 
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

spi: sifive: Simplify clock handling with devm_clk_get_enabled()

2026-05-23T11:05:01+00:00

[ Upstream commit 140039c23aca067b9ff0242e3c0ce96276bb95f3 ]

Replace devm_clk_get() followed by clk_prepare_enable() with
devm_clk_get_enabled() for the bus clock. This reduces boilerplate code
and error handling, as the managed API automatically disables the clock
when the device is removed or if probe fails.

Remove the now-unnecessary clk_disable_unprepare() calls from the probe
error path and the remove callback. Adjust the error handling to use the
existing put_host label.

Signed-off-by: Pei Xiao 
Link: https://patch.msgid.link/73d0d8ecb4e1af5a558d6a7866c0f886d94fe3d1.1773885292.git.xiaopei01@kylinos.cn
Signed-off-by: Mark Brown 
Stable-dep-of: 0f25236694a2 ("spi: sifive: fix controller deregistration")
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman