linux.git/kernel/bpf/offload.c, branch v6.18.21

net: move misc netdev_lock flavors to a separate header

2025-03-08T17:06:50+00:00

Move the more esoteric helpers for netdev instance lock to
a dedicated header. This avoids growing netdevice.h to infinity
and makes rebuilding the kernel much faster (after touching
the header with the helpers).

The main netdev_lock() / netdev_unlock() functions are used
in static inlines in netdevice.h and will probably be used
most commonly, so keep them in netdevice.h.

Acked-by: Stanislav Fomichev 
Link: https://patch.msgid.link/20250307183006.2312761-1-kuba@kernel.org
Signed-off-by: Jakub Kicinski

bpf: fix a possible NULL deref in bpf_map_offload_map_alloc()

2025-03-08T03:09:39+00:00

Call bpf_dev_offload_check() before netdev_lock_ops().

This is needed if attr->map_ifindex is not valid.

Oops: general protection fault, probably for non-canonical address 0xdffffc0000000197: 0000 [#1] PREEMPT SMP KASAN PTI
KASAN: null-ptr-deref in range [0x0000000000000cb8-0x0000000000000cbf]
 RIP: 0010:netdev_need_ops_lock include/linux/netdevice.h:2792 [inline]
 RIP: 0010:netdev_lock_ops include/linux/netdevice.h:2803 [inline]
 RIP: 0010:bpf_map_offload_map_alloc+0x19a/0x910 kernel/bpf/offload.c:533
Call Trace:
 
  map_create+0x946/0x11c0 kernel/bpf/syscall.c:1455
  __sys_bpf+0x6d3/0x820 kernel/bpf/syscall.c:5777
  __do_sys_bpf kernel/bpf/syscall.c:5902 [inline]
  __se_sys_bpf kernel/bpf/syscall.c:5900 [inline]
  __x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:5900
  do_syscall_x64 arch/x86/entry/common.c:52 [inline]
  do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83

Fixes: 97246d6d21c2 ("net: hold netdev instance lock during ndo_bpf")
Reported-by: syzbot+0c7bfd8cf3aecec92708@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/netdev/67caa2b1.050a0220.15b4b9.0077.GAE@google.com/T/#u
Signed-off-by: Eric Dumazet 
Acked-by: Stanislav Fomichev 
Link: https://patch.msgid.link/20250307074303.1497911-1-edumazet@google.com
Signed-off-by: Jakub Kicinski

net: hold netdev instance lock during ndo_bpf

2025-03-06T20:59:44+00:00

Cover the paths that come via bpf system call and XSK bind.

Cc: Saeed Mahameed 
Signed-off-by: Stanislav Fomichev 
Link: https://patch.msgid.link/20250305163732.2766420-10-sdf@fomichev.me
Signed-off-by: Jakub Kicinski

Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net

2023-09-21T19:49:45+00:00

Cross-merge networking fixes after downstream PR.

No conflicts.

Signed-off-by: Paolo Abeni

bpf: Allow to use kfunc XDP hints and frags together

2023-09-15T18:39:46+00:00

There is no fundamental reason, why multi-buffer XDP and XDP kfunc RX hints
cannot coexist in a single program.

Allow those features to be used together by modifying the flags condition
for dev-bound-only programs, segments are still prohibited for fully
offloaded programs, hence additional check.

Suggested-by: Stanislav Fomichev 
Link: https://lore.kernel.org/bpf/CAKH8qBuzgtJj=OKMdsxEkyML36VsAuZpcrsXcyqjdKXSJCBq=Q@mail.gmail.com/
Reviewed-by: Maciej Fijalkowski 
Signed-off-by: Larysa Zaremba 
Acked-by: Stanislav Fomichev 
Link: https://lore.kernel.org/r/20230915083914.65538-1-larysa.zaremba@intel.com
Signed-off-by: Martin KaFai Lau

bpf: expose information about supported xdp metadata kfunc

2023-09-15T18:26:58+00:00

Add new xdp-rx-metadata-features member to netdev netlink
which exports a bitmask of supported kfuncs. Most of the patch
is autogenerated (headers), the only relevant part is netdev.yaml
and the changes in netdev-genl.c to marshal into netlink.

Example output on veth:

$ ip link add veth0 type veth peer name veth1 # ifndex == 12
$ ./tools/net/ynl/samples/netdev 12

Select ifc ($ifindex; or 0 = dump; or -2 ntf check): 12
   veth1[12]    xdp-features (23): basic redirect rx-sg xdp-rx-metadata-features (3): timestamp hash xdp-zc-max-segs=0

Cc: netdev@vger.kernel.org
Cc: Willem de Bruijn 
Signed-off-by: Stanislav Fomichev 
Link: https://lore.kernel.org/r/20230913171350.369987-3-sdf@google.com
Signed-off-by: Martin KaFai Lau

bpf: make it easier to add new metadata kfunc

2023-09-15T18:26:58+00:00

No functional changes.

Instead of having hand-crafted code in bpf_dev_bound_resolve_kfunc,
move kfunc <> xmo handler relationship into XDP_METADATA_KFUNC_xxx.
This way, any time new kfunc is added, we don't have to touch
bpf_dev_bound_resolve_kfunc.

Also document XDP_METADATA_KFUNC_xxx arguments since we now have
more than two and it might be confusing what is what.

Cc: netdev@vger.kernel.org
Cc: Willem de Bruijn 
Signed-off-by: Stanislav Fomichev 
Link: https://lore.kernel.org/r/20230913171350.369987-2-sdf@google.com
Signed-off-by: Martin KaFai Lau

bpf: Avoid dummy bpf_offload_netdev in __bpf_prog_dev_bound_init

2023-09-12T05:06:06+00:00

Fix for a bug observable under the following sequence of events:
1. Create a network device that does not support XDP offload.
2. Load a device bound XDP program with BPF_F_XDP_DEV_BOUND_ONLY flag
   (such programs are not offloaded).
3. Load a device bound XDP program with zero flags
   (such programs are offloaded).

At step (2) __bpf_prog_dev_bound_init() associates with device (1)
a dummy bpf_offload_netdev struct with .offdev field set to NULL.
At step (3) __bpf_prog_dev_bound_init() would reuse dummy struct
allocated at step (2).
However, downstream usage of the bpf_offload_netdev assumes that
.offdev field can't be NULL, e.g. in bpf_prog_offload_verifier_prep().

Adjust __bpf_prog_dev_bound_init() to require bpf_offload_netdev
with non-NULL .offdev for offloaded BPF programs.

Fixes: 2b3486bc2d23 ("bpf: Introduce device-bound XDP programs")
Reported-by: syzbot+291100dcb32190ec02a8@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/bpf/000000000000d97f3c060479c4f8@google.com/
Signed-off-by: Eduard Zingerman 
Link: https://lore.kernel.org/r/20230912005539.2248244-2-eddyz87@gmail.com
Signed-off-by: Martin KaFai Lau

net: invert the netdevice.h vs xdp.h dependency

2023-08-03T15:38:07+00:00

xdp.h is far more specific and is included in only 67 other
files vs netdevice.h's 1538 include sites.
Make xdp.h include netdevice.h, instead of the other way around.
This decreases the incremental allmodconfig builds size when
xdp.h is touched from 5947 to 662 objects.

Move bpf_prog_run_xdp() to xdp.h, seems appropriate and filter.h
is a mega-header in its own right so it's nice to avoid xdp.h
getting included there as well.

The only unfortunate part is that the typedef for xdp_features_t
has to move to netdevice.h, since its embedded in struct netdevice.

Signed-off-by: Jakub Kicinski 
Acked-by: Jesper Dangaard Brouer 
Link: https://lore.kernel.org/r/20230803010230.1755386-4-kuba@kernel.org
Signed-off-by: Martin KaFai Lau

bpf: netdev: init the offload table earlier

2023-05-15T14:07:41+00:00

Some netdevices may get unregistered before late_initcall(),
we have to move the hashtable init earlier.

Fixes: f1fc43d03946 ("bpf: Move offload initialization into late_initcall")
Closes: https://bugzilla.kernel.org/show_bug.cgi?id=217399
Signed-off-by: Jakub Kicinski 
Acked-by: Stanislav Fomichev 
Link: https://lore.kernel.org/r/20230505215836.491485-1-kuba@kernel.org
Signed-off-by: Alexei Starovoitov