Steady stream of fixes. Last two weeks feel comparable to the two
weeks before the merge window. Lots of AI-aided bug discovery.
A newer big source is Sashiko/Gemini (Roman Gushchin's system),
which points out issues in existing code during patch review
(maybe 25% of fixes here likely originating from Sashiko).
Nice thing is these are often fixed by the respective maintainers,
not drive-bys.
Current release - new code bugs:
- kconfig: MDIO_PIC64HPSC should depend on ARCH_MICROCHIP
Previous releases - regressions:
- add async ndo_set_rx_mode and switch drivers which we promised
to be called under the per-netdev mutex to it
- dsa: remove duplicate netdev_lock_ops() for conduit ethtool ops
- hv_sock: report EOF instead of -EIO for FIN
- vsock/virtio: fix MSG_PEEK calculation on bytes to copy
Previous releases - always broken:
- ipv6: fix possible UAF in icmpv6_rcv()
- icmp: validate reply type before using icmp_pointers
- af_unix: drop all SCM attributes for SOCKMAP
- netfilter: fix a number of bugs in the osf (OS fingerprinting)
- eth: intel: fix timestamp interrupt configuration for E825C
Misc:
- bunch of data-race annotations
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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Merge tag 'net-7.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Pull networking fixes from Jakub Kicinski:
"Including fixes from Netfilter.
Steady stream of fixes. Last two weeks feel comparable to the two
weeks before the merge window. Lots of AI-aided bug discovery. A newer
big source is Sashiko/Gemini (Roman Gushchin's system), which points
out issues in existing code during patch review (maybe 25% of fixes
here likely originating from Sashiko). Nice thing is these are often
fixed by the respective maintainers, not drive-bys.
Current release - new code bugs:
- kconfig: MDIO_PIC64HPSC should depend on ARCH_MICROCHIP
Previous releases - regressions:
- add async ndo_set_rx_mode and switch drivers which we promised to
be called under the per-netdev mutex to it
- dsa: remove duplicate netdev_lock_ops() for conduit ethtool ops
- hv_sock: report EOF instead of -EIO for FIN
- vsock/virtio: fix MSG_PEEK calculation on bytes to copy
Previous releases - always broken:
- ipv6: fix possible UAF in icmpv6_rcv()
- icmp: validate reply type before using icmp_pointers
- af_unix: drop all SCM attributes for SOCKMAP
- netfilter: fix a number of bugs in the osf (OS fingerprinting)
- eth: intel: fix timestamp interrupt configuration for E825C
Misc:
- bunch of data-race annotations"
* tag 'net-7.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (148 commits)
rxrpc: Fix error handling in rxgk_extract_token()
rxrpc: Fix re-decryption of RESPONSE packets
rxrpc: Fix rxrpc_input_call_event() to only unshare DATA packets
rxrpc: Fix missing validation of ticket length in non-XDR key preparsing
rxgk: Fix potential integer overflow in length check
rxrpc: Fix conn-level packet handling to unshare RESPONSE packets
rxrpc: Fix potential UAF after skb_unshare() failure
rxrpc: Fix rxkad crypto unalignment handling
rxrpc: Fix memory leaks in rxkad_verify_response()
net: rds: fix MR cleanup on copy error
m68k: mvme147: Make me the maintainer
net: txgbe: fix firmware version check
selftests/bpf: check epoll readiness during reuseport migration
tcp: call sk_data_ready() after listener migration
vhost_net: fix sleeping with preempt-disabled in vhost_net_busy_poll()
ipv6: Cap TLV scan in ip6_tnl_parse_tlv_enc_lim
tipc: fix double-free in tipc_buf_append()
llc: Return -EINPROGRESS from llc_ui_connect()
ipv4: icmp: validate reply type before using icmp_pointers
selftests/net: packetdrill: cover RFC 5961 5.2 challenge ACK on both edges
...
- cx92755: convert I2C bindings to DT schema
- mediatek: add optional bus power management during transfers
- pxa: handle early bus busy condition
- MAINTAINERS: update I2C RUST entry
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Merge tag 'i2c-for-7.1-rc1-part2' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux
Pull more i2c updates from Wolfram Sang:
- cx92755: convert I2C bindings to DT schema
- mediatek: add optional bus power management during transfers
- pxa: handle early bus busy condition
- MAINTAINERS: update I2C RUST entry
* tag 'i2c-for-7.1-rc1-part2' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux:
MAINTAINERS: add Rust I2C tree and update Igor Korotin's email
i2c: mediatek: add bus regulator control for power saving
dt-bindings: i2c: cnxt,cx92755-i2c: Convert to DT schema
i2c: pxa: handle 'Early Bus Busy' condition on Armada 3700
- use register_sys_off_handler(SYS_OFF_MODE_RESTART) instead of the
deprecated register_restart_handler()
- drop custom ucontext.h and reuse asm-generic ucontext.h
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Merge tag 'xtensa-20260422' of https://github.com/jcmvbkbc/linux-xtensa
Pull Xtensa updates from Max Filippov:
- use register_sys_off_handler(SYS_OFF_MODE_RESTART) instead of
the deprecated register_restart_handler()
- drop custom ucontext.h and reuse asm-generic ucontext.h
* tag 'xtensa-20260422' of https://github.com/jcmvbkbc/linux-xtensa:
xtensa: uapi: Reuse asm-generic ucontext.h
xtensa: xtfpga: Use register_sys_off_handler(SYS_OFF_MODE_RESTART)
xtensa: xt2000: Use register_sys_off_handler(SYS_OFF_MODE_RESTART)
xtensa: ISS: Use register_sys_off_handler(SYS_OFF_MODE_RESTART)
Andrew Lunn says:
====================
Remove a number of ISA and PCMCIA Ethernet drivers
These old drivers have not been much of a Maintenance burden until
recently. Now there are more newbies using AI and fuzzers finding
issues, resulting in more work for Maintainers. Fixing these old
drivers make little sense, if it is not clear they have users.
These mostly ISA and PCMCIA Ethernet devices, mostly from the last
century, a couple from 2001 or 2002. It seems unlikely they are still
used. However, remove them one patch at a time so they can be brought
back if somebody still has the hardware, runs modern kernels and wants
to take up the roll of driver Maintainer.
====================
Link: https://patch.msgid.link/20260422-v7-0-0-net-next-driver-removal-v1-v2-0-08a5b59784d5@lunn.ch
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
The smc91c92 was written by David A Hinds in 1999. It is an PCMCIA
device, so unlikely to be used with modern kernels.
Remove the Documentation as well, since it refers to kernel versions
1.2.13 until 1.3.71 and FTP sites which no longer exist.
Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Link: https://patch.msgid.link/20260422-v7-0-0-net-next-driver-removal-v1-v2-8-08a5b59784d5@lunn.ch
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Christian Brauner <brauner@kernel.org> says:
ep_remove() (via __ep_remove_file()) cleared file->f_ep under
file->f_lock but then kept using @file in the same critical section:
is_file_epoll(), hlist_del_rcu() through the head, spin_unlock. A
concurrent __fput() on the watched eventpoll caught the transient
NULL in eventpoll_release()'s lockless fast path, skipped
eventpoll_release_file() entirely, and ran to ep_eventpoll_release()
-> ep_clear_and_put() -> ep_free(). That kfree()s the struct
eventpoll whose embedded ->refs hlist_head is exactly where
epi->fllink.pprev points and the subsequent hlist_del_rcu()'s
"*pprev = next" scribbles into freed kmalloc-192 memory, which is
the slab-use-after-free KASAN caught.
struct file is SLAB_TYPESAFE_BY_RCU on top of that so the same window
also lets the slot recycle while ep_remove() is still nominally
inside file->f_lock. The upshot is an attacker-influencable
kmem_cache_free() against the wrong slab cache.
The comment on eventpoll_release()'s fast path - "False positives
simply cannot happen because the file in on the way to be removed
and nobody ( but eventpoll ) has still a reference to this file" -
was itself the wrong invariant this race exploits.
The fix pins @file via epi_fget() at the top of ep_remove() and
gates the f_ep clear / hlist_del_rcu() on the pin succeeding. With
the pin held __fput() cannot start which transitively keeps the
watched struct eventpoll alive across the critical section and also
prevents the struct file slot from recycling. Both UAFs are closed.
If the pin fails __fput() is already in flight on @file. Because we
bail before clearing f_ep that path takes eventpoll_release()'s slow
path into eventpoll_release_file() which blocks on ep->mtx until
ep_clear_and_put() drops it and then cleans up the orphaned epi. The
bailed epi's share of ep->refcount stays intact so
ep_clear_and_put()'s trailing ep_refcount_dec_and_test() cannot free
the eventpoll out from under eventpoll_release_file().
With epi_fget() now gating every ep_remove() call the epi->dying
flag becomes vestigial. epi->dying == true always coincides with
file_ref_get() == false because __fput() is reachable only once the
refcount hits zero and the refcount is monotone there. The last
patch drops the flag and leaves a single coordination mechanism
instead of two.
* patches from https://patch.msgid.link/20260423-work-epoll-uaf-v1-0-2470f9eec0f5@kernel.org:
eventpoll: drop vestigial epi->dying flag
eventpoll: drop dead bool return from __ep_remove_epi()
eventpoll: refresh eventpoll_release() fast-path comment
eventpoll: move f_lock acquisition into __ep_remove_file()
eventpoll: fix ep_remove struct eventpoll / struct file UAF
eventpoll: move epi_fget() up
eventpoll: rename ep_remove_safe() back to ep_remove()
eventpoll: kill __ep_remove()
eventpoll: split __ep_remove()
eventpoll: use hlist_is_singular_node() in __ep_remove()
Link: https://patch.msgid.link/20260423-work-epoll-uaf-v1-0-2470f9eec0f5@kernel.org
Signed-off-by: Christian Brauner <brauner@kernel.org>
With ep_remove() now pinning @file via epi_fget() across the
f_ep clear and hlist_del_rcu(), the dying flag no longer
orchestrates anything: it was set in eventpoll_release_file()
(which only runs from __fput(), i.e. after @file's refcount has
reached zero) and read in __ep_remove() / ep_remove() as a cheap
bail before attempting the same synchronization epi_fget() now
provides unconditionally.
The implication is simple: epi->dying == true always coincides
with file_ref_get(&file->f_ref) == false, because __fput() is
reachable only once the refcount hits zero and the refcount is
monotone in that state. The READ_ONCE(epi->dying) in ep_remove()
therefore selects exactly the same callers that epi_fget() would
reject, just one atomic cheaper. That's not worth a struct
field, a second coordination mechanism, and the comments on
both.
Refresh the eventpoll_release_file() comment to describe what
actually makes the path race-free now (the pin in ep_remove()).
No functional change: the correctness argument is unchanged,
only the mechanism is now a single one instead of two.
Link: https://patch.msgid.link/20260423-work-epoll-uaf-v1-10-2470f9eec0f5@kernel.org
Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>
ep_remove_epi() always returns true -- the "can be disposed"
answer was meaningful back when the dying-check lived inside the
pre-split __ep_remove(), but after that check moved to ep_remove()
the return value is just noise. Both callers gate on it
unconditionally:
if (ep_remove_epi(ep, epi))
WARN_ON_ONCE(ep_refcount_dec_and_test(ep));
dispose = ep_remove_epi(ep, epi);
...
if (dispose && ep_refcount_dec_and_test(ep))
ep_free(ep);
Make ep_remove_epi() return void, drop the dispose local in
eventpoll_release_file(), and the useless conditionals at both
callers. No functional change.
Link: https://patch.msgid.link/20260423-work-epoll-uaf-v1-9-2470f9eec0f5@kernel.org
Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>
The old comment justified the lockless READ_ONCE(file->f_ep) check
with "False positives simply cannot happen because the file is on
the way to be removed and nobody ( but eventpoll ) has still a
reference to this file." That reasoning was the root of the UAF
fixed in "eventpoll: fix ep_remove struct eventpoll / struct file
UAF": __ep_remove() could clear f_ep while another close raced
past the fast path and freed the watched eventpoll / recycled the
struct file slot.
With ep_remove() now pinning @file via epi_fget() across the f_ep
clear and hlist_del_rcu(), the invariant is re-established for the
right reason: anyone who might clear f_ep holds @file alive for
the duration, so a NULL observation really does mean no
concurrent eventpoll path has work left on this file. Refresh the
comment accordingly so the next reader doesn't inherit the broken
model.
Link: https://patch.msgid.link/20260423-work-epoll-uaf-v1-8-2470f9eec0f5@kernel.org
Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>
Let the helper own its critical section end-to-end: take &file->f_lock
at the top, read file->f_ep inside the lock, release on exit. Callers
(ep_remove() and eventpoll_release_file()) no longer need to wrap the
call, and the function-comment lock-handoff contract is gone.
Link: https://patch.msgid.link/20260423-work-epoll-uaf-v1-7-2470f9eec0f5@kernel.org
Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>
ep_remove() (via ep_remove_file()) cleared file->f_ep under
file->f_lock but then kept using @file inside the critical section
(is_file_epoll(), hlist_del_rcu() through the head, spin_unlock).
A concurrent __fput() taking the eventpoll_release() fastpath in
that window observed the transient NULL, skipped
eventpoll_release_file() and ran to f_op->release / file_free().
For the epoll-watches-epoll case, f_op->release is
ep_eventpoll_release() -> ep_clear_and_put() -> ep_free(), which
kfree()s the watched struct eventpoll. Its embedded ->refs
hlist_head is exactly where epi->fllink.pprev points, so the
subsequent hlist_del_rcu()'s "*pprev = next" scribbles into freed
kmalloc-192 memory.
In addition, struct file is SLAB_TYPESAFE_BY_RCU, so the slot
backing @file could be recycled by alloc_empty_file() --
reinitializing f_lock and f_ep -- while ep_remove() is still
nominally inside that lock. The upshot is an attacker-controllable
kmem_cache_free() against the wrong slab cache.
Pin @file via epi_fget() at the top of ep_remove() and gate the
critical section on the pin succeeding. With the pin held @file
cannot reach refcount zero, which holds __fput() off and
transitively keeps the watched struct eventpoll alive across the
hlist_del_rcu() and the f_lock use, closing both UAFs.
If the pin fails @file has already reached refcount zero and its
__fput() is in flight. Because we bailed before clearing f_ep,
that path takes the eventpoll_release() slow path into
eventpoll_release_file() and blocks on ep->mtx until the waiter
side's ep_clear_and_put() drops it. The bailed epi's share of
ep->refcount stays intact, so the trailing ep_refcount_dec_and_test()
in ep_clear_and_put() cannot free the eventpoll out from under
eventpoll_release_file(); the orphaned epi is then cleaned up
there.
A successful pin also proves we are not racing
eventpoll_release_file() on this epi, so drop the now-redundant
re-check of epi->dying under f_lock. The cheap lockless
READ_ONCE(epi->dying) fast-path bailout stays.
Fixes: 58c9b016e1 ("epoll: use refcount to reduce ep_mutex contention")
Reported-by: Jaeyoung Chung <jjy600901@snu.ac.kr>
Link: https://patch.msgid.link/20260423-work-epoll-uaf-v1-6-2470f9eec0f5@kernel.org
Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>
With __ep_remove() gone, the double-underscore on __ep_remove_file()
and __ep_remove_epi() no longer contrasts with a __-less parent and
just reads as noise. Rename both to ep_remove_file() and
ep_remove_epi(). No functional change.
Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>
Remove the boolean conditional in __ep_remove() and restructure the code
so the check for racing with eventpoll_release_file() are only done in
the ep_remove_safe() path where they belong.
Link: https://patch.msgid.link/20260423-work-epoll-uaf-v1-3-2470f9eec0f5@kernel.org
Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>
Replace the open-coded "epi is the only entry in file->f_ep" check
with hlist_is_singular_node(). Same semantics, and the helper avoids
the head-cacheline access in the common false case.
Link: https://patch.msgid.link/20260423-work-epoll-uaf-v1-1-2470f9eec0f5@kernel.org
Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>
When a metadata block is referenced by multiple inodes and tracked by
metadata bh infrastructure (which is forbidden and generally indicates
filesystem corruption), it can happen that mmb_mark_buffer_dirty() is
called for two different mmb structures in parallel. This can lead to a
corruption of mmb linked list. Handle that situation gracefully (at
least from mmb POV) by serializing on setting bh->b_mmb.
Reported-by: Ruikai Peng <ruikai@pwno.io>
Signed-off-by: Jan Kara <jack@suse.cz>
Link: https://patch.msgid.link/20260423090311.10955-2-jack@suse.cz
Signed-off-by: Christian Brauner <brauner@kernel.org>
Use the correct parameter name ("__ns") for function parameter kernel-doc
to avoid 3 warnings:
Warning: include/linux/nstree.h:68 function parameter '__ns' not described in 'ns_tree_add_raw'
Warning: include/linux/nstree.h:77 function parameter '__ns' not described in 'ns_tree_add'
Warning: include/linux/nstree.h:88 function parameter '__ns' not described in 'ns_tree_remove'
Fixes: 885fc8ac0a ("nstree: make iterator generic")
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Link: https://patch.msgid.link/20260416215429.948898-1-rdunlap@infradead.org
Signed-off-by: Christian Brauner <brauner@kernel.org>
[BUG]
Recently, our internal syzkaller testing uncovered a null pointer
dereference issue:
BUG: kernel NULL pointer dereference, address: 0000000000000000
...
[ 51.111664] filemap_read_folio+0x25/0xe0
[ 51.112410] filemap_fault+0xad7/0x1250
[ 51.113112] __do_fault+0x4b/0x460
[ 51.113699] do_pte_missing+0x5bc/0x1db0
[ 51.114250] ? __pte_offset_map+0x23/0x170
[ 51.114822] __handle_mm_fault+0x9f8/0x1680
...
Crash analysis showed the file involved was an AIO ring file. The
phenomenon triggered is the same as the issue described in [1].
[CAUSE]
Consider the following scenario: userspace sets up an AIO context via
io_setup(), which creates a VMA covering the entire ring buffer. Then
userspace calls mremap() with the AIO ring address as the source, a smaller
old_len (less than the full ring size), MREMAP_MAYMOVE set, and without
MREMAP_DONTUNMAP. The kernel will relocate the requested portion to a new
destination address.
During this move, __split_vma() splits the original AIO ring VMA. The
requested portion is unmapped from the source and re-established at the
destination, while the remainder stays at the original source address as
an orphan VMA. The aio_ring_mremap() callback fires on the new destination
VMA, updating ctx->mmap_base to the destination address. But the callback
is unaware that only a partial region was moved and that an orphan VMA
still exists at the source:
source(AIO):
+-------------------+---------------------+
| moved to dest | orphan VMA (AIO) |
+-------------------+---------------------+
A A+partial_len A+ctx->mmap_size
dest:
+-------------------+
| moved VMA (AIO) |
+-------------------+
B B+partial_len
Later, io_destroy() calls vm_munmap(ctx->mmap_base, ctx->mmap_size), which
unmaps the destination. This not only fails to unmap the orphan VMA at the
source, but also overshoots the destination VMA and may unmap unrelated
mappings adjacent to it! After put_aio_ring_file() calls truncate_setsize()
to remove all pages from the pagecache, any subsequent access to the orphan
VMA triggers filemap_fault(), which calls a_ops->read_folio(). Since aio
does not implement read_folio, this results in a NULL pointer dereference.
[FIX]
Note that expanding mremap (new_len > old_len) is already rejected because
AIO ring VMAs are created with VM_DONTEXPAND. The only problematic case is
a partial move where "old_len == new_len" but both are smaller than the
full ring size.
Fix this by checking in aio_ring_mremap() that the new VMA covers the
entire ring. This ensures the AIO ring is always moved as a whole,
preventing orphan VMAs and the subsequent crash.
[1]: https://lore.kernel.org/all/20260413010814.548568-1-wozizhi@huawei.com/
Signed-off-by: Zizhi Wo <wozizhi@huaweicloud.com>
Link: https://patch.msgid.link/20260418060634.3713620-1-wozizhi@huaweicloud.com
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Christian Brauner <brauner@kernel.org>
fuse_add_dirent_to_cache() computes a serialized dirent size from the
server-controlled namelen field and copies the dirent into a single
page-cache page. The existing logic only checks whether the dirent fits
in the remaining space of the current page and advances to a fresh page
if not. It never checks whether the dirent itself exceeds PAGE_SIZE.
As a result, a malicious FUSE server can return a dirent with
namelen=4095, producing a serialized record size of 4120 bytes. On 4 KiB
page systems this causes memcpy() to overflow the cache page by 24 bytes
into the following kernel page.
Reject dirents that cannot fit in a single page before copying them into
the readdir cache.
Fixes: 69e3455115 ("fuse: allow caching readdir")
Cc: stable@vger.kernel.org # v6.16+
Assisted-by: Bynario AI
Signed-off-by: Samuel Page <sam@bynar.io>
Reported-by: Qi Tang <tpluszz77@gmail.com>
Reported-by: Zijun Hu <nightu@northwestern.edu>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Link: https://patch.msgid.link/20260420090139.662772-1-mszeredi@redhat.com
Signed-off-by: Christian Brauner <brauner@kernel.org>
inode_switch_wbs_work_fn() has a loop like:
wb_get(new_wb);
while (1) {
list = llist_del_all(&new_wb->switch_wbs_ctxs);
/* Nothing to do? */
if (!list)
break;
... process the items ...
}
Now adding of items to the list looks like:
wb_queue_isw()
if (llist_add(&isw->list, &wb->switch_wbs_ctxs))
queue_work(isw_wq, &wb->switch_work);
Because inode_switch_wbs_work_fn() loops when processing isw items, it
can happen that wb->switch_work is pending while wb->switch_wbs_ctxs is
empty. This is a problem because in that case wb can get freed (no isw
items -> no wb reference) while the work is still pending causing
use-after-free issues.
We cannot just fix this by cancelling work when freeing wb because that
could still trigger problematic 0 -> 1 transitions on wb refcount due to
wb_get() in inode_switch_wbs_work_fn(). It could be all handled with
more careful code but that seems unnecessarily complex so let's avoid
that until it is proven that the looping actually brings practical
benefit. Just remove the loop from inode_switch_wbs_work_fn() instead.
That way when wb_queue_isw() queues work, we are guaranteed we have
added the first item to wb->switch_wbs_ctxs and nobody is going to
remove it (and drop the wb reference it holds) until the queued work
runs.
Fixes: e1b849cfa6 ("writeback: Avoid contention on wb->list_lock when switching inodes")
CC: stable@vger.kernel.org
Signed-off-by: Jan Kara <jack@suse.cz>
Link: https://patch.msgid.link/20260413093618.17244-2-jack@suse.cz
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>
[BUG]
Recently, our internal syzkaller testing uncovered a null pointer
dereference issue:
BUG: kernel NULL pointer dereference, address: 0000000000000000
...
[ 51.111664] filemap_read_folio+0x25/0xe0
[ 51.112410] filemap_fault+0xad7/0x1250
[ 51.113112] __do_fault+0x4b/0x460
[ 51.113699] do_pte_missing+0x5bc/0x1db0
[ 51.114250] ? __pte_offset_map+0x23/0x170
[ 51.114822] __handle_mm_fault+0x9f8/0x1680
[ 51.115408] handle_mm_fault+0x24c/0x570
[ 51.115958] do_user_addr_fault+0x226/0xa50
...
Crash analysis showed the file involved was an AIO ring file.
[CAUSE]
PARENT process CHILD process
t=0 io_setup(1, &ctx)
[access ctx addr]
fork()
io_destroy
vm_munmap // not affect child vma
percpu_ref_put
...
put_aio_ring_file
t=1 [access ctx addr] // pagefault
...
__do_fault
filemap_fault
max_idx = DIV_ROUND_UP(i_size_read(inode), PAGE_SIZE)
t=2 truncate_setsize
truncate_pagecache
t=3 filemap_get_folio // no folio, create folio
__filemap_get_folio(..., FGP_CREAT, ...) // page_not_uptodate
filemap_read_folio(file, mapping->a_ops->read_folio, folio) // oops!
At t=0, the parent process calls io_setup and then fork. The child process
gets its own VMA but without any PTEs. The parent then calls io_destroy.
Before i_size is truncated to 0, at t=1 the child process accesses this AIO
ctx address and triggers a pagefault. After the max_idx check passes, at
t=2 the parent calls truncate_setsize and truncate_pagecache. At t=3 the
child fails to obtain the folio, falls into the "page_not_uptodate" path,
and hits this problem because AIO does not implement "read_folio".
[Fix]
Fix this by marking the AIO ring buffer VMA with VM_DONTCOPY so
that fork()'s dup_mmap() skips it entirely. This is the correct
semantic because:
1) The child's ioctx_table is already reset to NULL by mm_init_aio() during
fork(), so the child has no AIO context and no way to perform any AIO
operations on this mapping.
2) The AIO ring VMA is only meaningful in conjunction with its associated
kioctx, which is never inherited across fork(). So child process with no
AIO context has no legitimate reason to access the ring buffer. Delivering
SIGSEGV on such an erroneous access is preferable to a kernel crash.
Signed-off-by: Zizhi Wo <wozizhi@huaweicloud.com>
Link: https://patch.msgid.link/20260413010814.548568-1-wozizhi@huawei.com
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Christian Brauner <brauner@kernel.org>
Mingyu Wang says:
====================
net: packetengines: remove obsolete PCI drivers
As discussed with Andrew Lunn, this patch series removes the obsolete
hamachi and yellowfin PCI drivers. Both drivers support hardware that
is over two decades old and no longer in active use.
Removing them eliminates dead code and reduces the overall maintenance
burden on the netdev subsystem.
====================
Jakub: trim defconfigs appropriately
Link: https://patch.msgid.link/20260422044820.485660-1-25181214217@stu.xidian.edu.cn
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Similar to the hamachi driver, the yellowfin driver supports hardware
that is over two decades old and no longer in active use.
Since yellowfin was the last remaining driver in the packetengines
vendor directory, we can now safely remove the entire directory and
drop its associated references from the parent Kconfig and Makefile.
This eliminates dead code and reduces the overall maintenance burden
on the netdev subsystem.
Signed-off-by: Mingyu Wang <25181214217@stu.xidian.edu.cn>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Link: https://patch.msgid.link/20260422044820.485660-3-25181214217@stu.xidian.edu.cn
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
The PacketEngine Hamachi driver is for PCI hardware that has been
obsolete for over two decades. It recently triggered arithmetic
exceptions during automated fuzzing.
As suggested by maintainers, remove the driver entirely to eliminate
dead code and reduce the maintenance burden.
Signed-off-by: Mingyu Wang <25181214217@stu.xidian.edu.cn>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Link: https://patch.msgid.link/20260422044820.485660-2-25181214217@stu.xidian.edu.cn
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
David Howells says:
====================
rxrpc: Miscellaneous fixes
Here are some fixes for rxrpc, as found by Sashiko[1]:
(1) Fix rxrpc_input_call_event() to only unshare DATA packets.
(2) Fix re-decryption of RESPONSE packets where a partially decrypted
skbuff gets requeued if there was a failure due to ENOMEM.
(3) Fix error handling in rxgk_extract_token() where the ENOMEM case is
unhandled.
Link: https://sashiko.dev/#/patchset/20260422161438.2593376-4-dhowells@redhat.com [1]
====================
Link: https://patch.msgid.link/20260423200909.3049438-1-dhowells@redhat.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
If a RESPONSE packet gets a temporary failure during processing, it may end
up in a partially decrypted state - and then get requeued for a retry.
Fix this by just discarding the packet; we will send another CHALLENGE
packet and thereby elicit a further response. Similarly, discard an
incoming CHALLENGE packet if we get an error whilst generating a RESPONSE;
the server will send another CHALLENGE.
Fixes: 17926a7932 ("[AF_RXRPC]: Provide secure RxRPC sockets for use by userspace and kernel both")
Closes: https://sashiko.dev/#/patchset/20260422161438.2593376-4-dhowells@redhat.com
Signed-off-by: David Howells <dhowells@redhat.com>
cc: Marc Dionne <marc.dionne@auristor.com>
cc: Jeffrey Altman <jaltman@auristor.com>
cc: Simon Horman <horms@kernel.org>
cc: linux-afs@lists.infradead.org
cc: stable@kernel.org
Link: https://patch.msgid.link/20260423200909.3049438-3-dhowells@redhat.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
David Howells says:
====================
rxrpc: Miscellaneous fixes
Here are some fixes for rxrpc, as found by Sashiko[1]:
(1) Fix leaks in rxkad_verify_response().
(2) Fix handling of rxkad-encrypted packets with crypto-misaligned
lengths.
(3) Fix problem with unsharing DATA packets potentially causing a crash in
the caller.
(4) Fix lack of unsharing of RESPONSE packets.
(5) Fix integer overflow in RxGK ticket length check.
(6) Fix missing length check in RxKAD tickets.
====================
Link: https://patch.msgid.link/20260422161438.2593376-1-dhowells@redhat.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
In rxrpc_preparse(), there are two paths for parsing key payloads: the
XDR path (for large payloads) and the non-XDR path (for payloads <= 28
bytes). While the XDR path (rxrpc_preparse_xdr_rxkad()) correctly
validates the ticket length against AFSTOKEN_RK_TIX_MAX, the non-XDR
path fails to do so.
This allows an unprivileged user to provide a very large ticket length.
When this key is later read via rxrpc_read(), the total
token size (toksize) calculation results in a value that exceeds
AFSTOKEN_LENGTH_MAX, triggering a WARN_ON().
[ 2001.302904] WARNING: CPU: 2 PID: 2108 at net/rxrpc/key.c:778 rxrpc_read+0x109/0x5c0 [rxrpc]
Fix this by adding a check in the non-XDR parsing path of rxrpc_preparse()
to ensure the ticket length does not exceed AFSTOKEN_RK_TIX_MAX,
bringing it into parity with the XDR parsing logic.
Fixes: 8a7a3eb4dd ("KEYS: RxRPC: Use key preparsing")
Fixes: 84924aac08 ("rxrpc: Fix checker warning")
Reported-by: Anderson Nascimento <anderson@allelesecurity.com>
Signed-off-by: Anderson Nascimento <anderson@allelesecurity.com>
Signed-off-by: David Howells <dhowells@redhat.com>
cc: Marc Dionne <marc.dionne@auristor.com>
cc: Jeffrey Altman <jaltman@auristor.com>
cc: Simon Horman <horms@kernel.org>
cc: linux-afs@lists.infradead.org
cc: stable@kernel.org
Link: https://patch.msgid.link/20260422161438.2593376-7-dhowells@redhat.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
The security operations that verify the RESPONSE packets decrypt bits of it
in place - however, the sk_buff may be shared with a packet sniffer, which
would lead to the sniffer seeing an apparently corrupt packet (actually
decrypted).
Fix this by handing a copy of the packet off to the specific security
handler if the packet was cloned.
Fixes: 17926a7932 ("[AF_RXRPC]: Provide secure RxRPC sockets for use by userspace and kernel both")
Closes: https://sashiko.dev/#/patchset/20260408121252.2249051-1-dhowells%40redhat.com
Signed-off-by: David Howells <dhowells@redhat.com>
cc: Marc Dionne <marc.dionne@auristor.com>
cc: Jeffrey Altman <jaltman@auristor.com>
cc: Simon Horman <horms@kernel.org>
cc: linux-afs@lists.infradead.org
cc: stable@kernel.org
Link: https://patch.msgid.link/20260422161438.2593376-5-dhowells@redhat.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
If skb_unshare() fails to unshare a packet due to allocation failure in
rxrpc_input_packet(), the skb pointer in the parent (rxrpc_io_thread())
will be NULL'd out. This will likely cause the call to
trace_rxrpc_rx_done() to oops.
Fix this by moving the unsharing down to where rxrpc_input_call_event()
calls rxrpc_input_call_packet(). There are a number of places prior to
that where we ignore DATA packets for a variety of reasons (such as the
call already being complete) for which an unshare is then avoided.
And with that, rxrpc_input_packet() doesn't need to take a pointer to the
pointer to the packet, so change that to just a pointer.
Fixes: 2d1faf7a0c ("rxrpc: Simplify skbuff accounting in receive path")
Closes: https://sashiko.dev/#/patchset/20260408121252.2249051-1-dhowells%40redhat.com
Signed-off-by: David Howells <dhowells@redhat.com>
cc: Marc Dionne <marc.dionne@auristor.com>
cc: Jeffrey Altman <jaltman@auristor.com>
cc: Simon Horman <horms@kernel.org>
cc: linux-afs@lists.infradead.org
cc: stable@kernel.org
Link: https://patch.msgid.link/20260422161438.2593376-4-dhowells@redhat.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Fix rxkad_verify_response() to free the ticket and the server key under all
circumstances by initialising the ticket pointer to NULL and then making
all paths through the function after the first allocation has been done go
through a single common epilogue that just releases everything - where all
the releases skip on a NULL pointer.
Fixes: 57af281e53 ("rxrpc: Tidy up abort generation infrastructure")
Fixes: ec832bd06d ("rxrpc: Don't retain the server key in the connection")
Closes: https://sashiko.dev/#/patchset/20260408121252.2249051-1-dhowells%40redhat.com
Signed-off-by: David Howells <dhowells@redhat.com>
cc: Marc Dionne <marc.dionne@auristor.com>
cc: Jeffrey Altman <jaltman@auristor.com>
cc: Simon Horman <horms@kernel.org>
cc: linux-afs@lists.infradead.org
cc: stable@kernel.org
Link: https://patch.msgid.link/20260422161438.2593376-2-dhowells@redhat.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
