linux-stable.git/include/linux, branch v6.1.73

genirq/affinity: Move group_cpus_evenly() into lib/

2024-01-10T16:10:33+00:00

[ Upstream commit f7b3ea8cf72f3d6060fe08e461805181e7450a13 ]

group_cpus_evenly() has become a generic function which can be used for
other subsystems than the interrupt subsystem, so move it into lib/.

Signed-off-by: Ming Lei 
Signed-off-by: Thomas Gleixner 
Reviewed-by: Christoph Hellwig 
Reviewed-by: Jens Axboe 
Link: https://lore.kernel.org/r/20221227022905.352674-6-ming.lei@redhat.com
Stable-dep-of: 0263f92fadbb ("lib/group_cpus.c: avoid acquiring cpu hotplug lock in group_cpus_evenly")
Signed-off-by: Sasha Levin

bpf, sockmap: af_unix stream sockets need to hold ref for pair sock

2024-01-10T16:10:32+00:00

[ Upstream commit 8866730aed5100f06d3d965c22f1c61f74942541 ]

AF_UNIX stream sockets are a paired socket. So sending on one of the pairs
will lookup the paired socket as part of the send operation. It is possible
however to put just one of the pairs in a BPF map. This currently increments
the refcnt on the sock in the sockmap to ensure it is not free'd by the
stack before sockmap cleans up its state and stops any skbs being sent/recv'd
to that socket.

But we missed a case. If the peer socket is closed it will be free'd by the
stack. However, the paired socket can still be referenced from BPF sockmap
side because we hold a reference there. Then if we are sending traffic through
BPF sockmap to that socket it will try to dereference the free'd pair in its
send logic creating a use after free. And following splat:

   [59.900375] BUG: KASAN: slab-use-after-free in sk_wake_async+0x31/0x1b0
   [59.901211] Read of size 8 at addr ffff88811acbf060 by task kworker/1:2/954
   [...]
   [59.905468] Call Trace:
   [59.905787]  
   [59.906066]  dump_stack_lvl+0x130/0x1d0
   [59.908877]  print_report+0x16f/0x740
   [59.910629]  kasan_report+0x118/0x160
   [59.912576]  sk_wake_async+0x31/0x1b0
   [59.913554]  sock_def_readable+0x156/0x2a0
   [59.914060]  unix_stream_sendmsg+0x3f9/0x12a0
   [59.916398]  sock_sendmsg+0x20e/0x250
   [59.916854]  skb_send_sock+0x236/0xac0
   [59.920527]  sk_psock_backlog+0x287/0xaa0

To fix let BPF sockmap hold a refcnt on both the socket in the sockmap and its
paired socket. It wasn't obvious how to contain the fix to bpf_unix logic. The
primarily problem with keeping this logic in bpf_unix was: In the sock close()
we could handle the deref by having a close handler. But, when we are destroying
the psock through a map delete operation we wouldn't have gotten any signal
thorugh the proto struct other than it being replaced. If we do the deref from
the proto replace its too early because we need to deref the sk_pair after the
backlog worker has been stopped.

Given all this it seems best to just cache it at the end of the psock and eat 8B
for the af_unix and vsock users. Notice dgram sockets are OK because they handle
locking already.

Fixes: 94531cfcbe79 ("af_unix: Add unix_stream_proto for sockmap")
Signed-off-by: John Fastabend 
Signed-off-by: Daniel Borkmann 
Reviewed-by: Jakub Sitnicki 
Link: https://lore.kernel.org/bpf/20231129012557.95371-2-john.fastabend@gmail.com
Signed-off-by: Sasha Levin

filemap: add a per-mapping stable writes flag

2024-01-10T16:10:32+00:00

[ Upstream commit 762321dab9a72760bf9aec48362f932717c9424d ]

folio_wait_stable waits for writeback to finish before modifying the
contents of a folio again, e.g. to support check summing of the data
in the block integrity code.

Currently this behavior is controlled by the SB_I_STABLE_WRITES flag
on the super_block, which means it is uniform for the entire file system.
This is wrong for the block device pseudofs which is shared by all
block devices, or file systems that can use multiple devices like XFS
witht the RT subvolume or btrfs (although btrfs currently reimplements
folio_wait_stable anyway).

Add a per-address_space AS_STABLE_WRITES flag to control the behavior
in a more fine grained way.  The existing SB_I_STABLE_WRITES is kept
to initialize AS_STABLE_WRITES to the existing default which covers
most cases.

Signed-off-by: Christoph Hellwig 
Link: https://lore.kernel.org/r/20231025141020.192413-2-hch@lst.de
Tested-by: Ilya Dryomov 
Reviewed-by: Matthew Wilcox (Oracle) 
Reviewed-by: Darrick J. Wong 
Signed-off-by: Christian Brauner 
Stable-dep-of: 1898efcdbed3 ("block: update the stable_writes flag in bdev_add")
Signed-off-by: Sasha Levin

mm, netfs, fscache: stop read optimisation when folio removed from pagecache

2024-01-10T16:10:31+00:00

[ Upstream commit b4fa966f03b7401ceacd4ffd7227197afb2b8376 ]

Fscache has an optimisation by which reads from the cache are skipped
until we know that (a) there's data there to be read and (b) that data
isn't entirely covered by pages resident in the netfs pagecache.  This is
done with two flags manipulated by fscache_note_page_release():

	if (...
	    test_bit(FSCACHE_COOKIE_HAVE_DATA, &cookie->flags) &&
	    test_bit(FSCACHE_COOKIE_NO_DATA_TO_READ, &cookie->flags))
		clear_bit(FSCACHE_COOKIE_NO_DATA_TO_READ, &cookie->flags);

where the NO_DATA_TO_READ flag causes cachefiles_prepare_read() to
indicate that netfslib should download from the server or clear the page
instead.

The fscache_note_page_release() function is intended to be called from
->releasepage() - but that only gets called if PG_private or PG_private_2
is set - and currently the former is at the discretion of the network
filesystem and the latter is only set whilst a page is being written to
the cache, so sometimes we miss clearing the optimisation.

Fix this by following Willy's suggestion[1] and adding an address_space
flag, AS_RELEASE_ALWAYS, that causes filemap_release_folio() to always call
->release_folio() if it's set, even if PG_private or PG_private_2 aren't
set.

Note that this would require folio_test_private() and page_has_private() to
become more complicated.  To avoid that, in the places[*] where these are
used to conditionalise calls to filemap_release_folio() and
try_to_release_page(), the tests are removed the those functions just
jumped to unconditionally and the test is performed there.

[*] There are some exceptions in vmscan.c where the check guards more than
just a call to the releaser.  I've added a function, folio_needs_release()
to wrap all the checks for that.

AS_RELEASE_ALWAYS should be set if a non-NULL cookie is obtained from
fscache and cleared in ->evict_inode() before truncate_inode_pages_final()
is called.

Additionally, the FSCACHE_COOKIE_NO_DATA_TO_READ flag needs to be cleared
and the optimisation cancelled if a cachefiles object already contains data
when we open it.

[dwysocha@redhat.com: call folio_mapping() inside folio_needs_release()]
  Link: https://github.com/DaveWysochanskiRH/kernel/commit/902c990e311120179fa5de99d68364b2947b79ec
Link: https://lkml.kernel.org/r/20230628104852.3391651-3-dhowells@redhat.com
Fixes: 1f67e6d0b188 ("fscache: Provide a function to note the release of a page")
Fixes: 047487c947e8 ("cachefiles: Implement the I/O routines")
Signed-off-by: David Howells 
Signed-off-by: Dave Wysochanski 
Reported-by: Rohith Surabattula 
Suggested-by: Matthew Wilcox 
Tested-by: SeongJae Park 
Cc: Daire Byrne 
Cc: Matthew Wilcox 
Cc: Linus Torvalds 
Cc: Steve French 
Cc: Shyam Prasad N 
Cc: Rohith Surabattula 
Cc: Dave Wysochanski 
Cc: Dominique Martinet 
Cc: Ilya Dryomov 
Cc: Andreas Dilger 
Cc: Jingbo Xu 
Cc: "Theodore Ts'o" 
Cc: Xiubo Li 
Signed-off-by: Andrew Morton 
Stable-dep-of: 1898efcdbed3 ("block: update the stable_writes flag in bdev_add")
Signed-off-by: Sasha Levin

f2fs: convert to use bitmap API

2024-01-10T16:10:30+00:00

[ Upstream commit 447286ebadaafa551550704ff0b42eb08b1d1cb2 ]

Let's use BIT() and GENMASK() instead of open it.

Signed-off-by: Yangtao Li 
Reviewed-by: Chao Yu 
Signed-off-by: Jaegeuk Kim 
Stable-dep-of: f5f3bd903a5d ("f2fs: set the default compress_level on ioctl")
Signed-off-by: Sasha Levin

bpf: handle ldimm64 properly in check_cfg()

2024-01-10T16:10:29+00:00

[ Upstream commit 3feb263bb516ee7e1da0acd22b15afbb9a7daa19 ]

ldimm64 instructions are 16-byte long, and so have to be handled
appropriately in check_cfg(), just like the rest of BPF verifier does.

This has implications in three places:
  - when determining next instruction for non-jump instructions;
  - when determining next instruction for callback address ldimm64
    instructions (in visit_func_call_insn());
  - when checking for unreachable instructions, where second half of
    ldimm64 is expected to be unreachable;

We take this also as an opportunity to report jump into the middle of
ldimm64. And adjust few test_verifier tests accordingly.

Acked-by: Eduard Zingerman 
Reported-by: Hao Sun 
Fixes: 475fb78fbf48 ("bpf: verifier (add branch/goto checks)")
Signed-off-by: Andrii Nakryiko 
Link: https://lore.kernel.org/r/20231110002638.4168352-2-andrii@kernel.org
Signed-off-by: Alexei Starovoitov 
Signed-off-by: Sasha Levin

bpf: decouple prune and jump points

2024-01-10T16:10:29+00:00

[ Upstream commit bffdeaa8a5af7200b0e74c9d5a41167f86626a36 ]

BPF verifier marks some instructions as prune points. Currently these
prune points serve two purposes.

It's a point where verifier tries to find previously verified state and
check current state's equivalence to short circuit verification for
current code path.

But also currently it's a point where jump history, used for precision
backtracking, is updated. This is done so that non-linear flow of
execution could be properly backtracked.

Such coupling is coincidental and unnecessary. Some prune points are not
part of some non-linear jump path, so don't need update of jump history.
On the other hand, not all instructions which have to be recorded in
jump history necessarily are good prune points.

This patch splits prune and jump points into independent flags.
Currently all prune points are marked as jump points to minimize amount
of changes in this patch, but next patch will perform some optimization
of prune vs jmp point placement.

No functional changes are intended.

Acked-by: John Fastabend 
Signed-off-by: Andrii Nakryiko 
Link: https://lore.kernel.org/r/20221206233345.438540-2-andrii@kernel.org
Signed-off-by: Alexei Starovoitov 
Stable-dep-of: 3feb263bb516 ("bpf: handle ldimm64 properly in check_cfg()")
Signed-off-by: Sasha Levin

udp: lockless UDP_ENCAP_L2TPINUDP / UDP_GRO

2024-01-10T16:10:28+00:00

[ Upstream commit ac9a7f4ce5dda1472e8f44096f33066c6ec1a3b4 ]

Move udp->encap_enabled to udp->udp_flags.

Add udp_test_and_set_bit() helper to allow lockless
udp_tunnel_encap_enable() implementation.

Signed-off-by: Eric Dumazet 
Reviewed-by: Willem de Bruijn 
Signed-off-by: Paolo Abeni 
Stable-dep-of: 70a36f571362 ("udp: annotate data-races around udp->encap_type")
Signed-off-by: Sasha Levin

udp: move udp->accept_udp_{l4|fraglist} to udp->udp_flags

2024-01-10T16:10:28+00:00

[ Upstream commit f5f52f0884a595ff99ab1a608643fe4025fca2d5 ]

These are read locklessly, move them to udp_flags to fix data-races.

Signed-off-by: Eric Dumazet 
Reviewed-by: Willem de Bruijn 
Signed-off-by: Paolo Abeni 
Stable-dep-of: 70a36f571362 ("udp: annotate data-races around udp->encap_type")
Signed-off-by: Sasha Levin

udp: move udp->gro_enabled to udp->udp_flags

2024-01-10T16:10:28+00:00

[ Upstream commit e1dc0615c6b08ef36414f08c011965b8fb56198b ]

syzbot reported that udp->gro_enabled can be read locklessly.
Use one atomic bit from udp->udp_flags.

Fixes: e20cf8d3f1f7 ("udp: implement GRO for plain UDP sockets.")
Reported-by: syzbot 
Signed-off-by: Eric Dumazet 
Reviewed-by: Willem de Bruijn 
Signed-off-by: Paolo Abeni 
Signed-off-by: Sasha Levin