linux.git/net/core/dev.c, branch v6.7-rc2 Linux kernel source tree net: Fix undefined behavior in netdev name allocation 2023-11-15T11:05:08+00:00 Gal Pressman gal@nvidia.com 2023-11-14T07:56:18+00:00 674e318089468ece99aef4796eaef7add57f36b2 Cited commit removed the strscpy() call and kept the snprintf() only. It is common to use 'dev->name' as the format string before a netdev is registered, this results in 'res' and 'name' pointers being equal. According to POSIX, if copying takes place between objects that overlap as a result of a call to sprintf() or snprintf(), the results are undefined. Add back the strscpy() and use 'buf' as an intermediate buffer. Fixes: 7ad17b04dc7b ("net: trust the bitmap in __dev_alloc_name()") Cc: Jakub Kicinski <kuba@kernel.org> Reviewed-by: Vlad Buslov <vladbu@nvidia.com> Signed-off-by: Gal Pressman <gal@nvidia.com> Reviewed-by: Jakub Kicinski <kuba@kernel.org> Reviewed-by: Simon Horman <horms@kernel.org> Reviewed-by: Jiri Pirko <jiri@nvidia.com> Signed-off-by: David S. Miller <davem@davemloft.net> 
Cited commit removed the strscpy() call and kept the snprintf() only.

It is common to use 'dev->name' as the format string before a netdev is
registered, this results in 'res' and 'name' pointers being equal.
According to POSIX, if copying takes place between objects that overlap
as a result of a call to sprintf() or snprintf(), the results are
undefined.

Add back the strscpy() and use 'buf' as an intermediate buffer.

Fixes: 7ad17b04dc7b ("net: trust the bitmap in __dev_alloc_name()")
Cc: Jakub Kicinski <kuba@kernel.org>
Reviewed-by: Vlad Buslov <vladbu@nvidia.com>
Signed-off-by: Gal Pressman <gal@nvidia.com>
Reviewed-by: Jakub Kicinski <kuba@kernel.org>
Reviewed-by: Simon Horman <horms@kernel.org>
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Merge tag 'for-netdev' of ssh://gitolite.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next 2023-10-27T03:02:41+00:00 Jakub Kicinski kuba@kernel.org 2023-10-27T03:02:40+00:00 c6f9b7138bf5c6b826175c9e0ad5f5dbfff4fa36 Daniel Borkmann says: ==================== pull-request: bpf-next 2023-10-26 We've added 51 non-merge commits during the last 10 day(s) which contain a total of 75 files changed, 5037 insertions(+), 200 deletions(-). The main changes are: 1) Add open-coded task, css_task and css iterator support. One of the use cases is customizable OOM victim selection via BPF, from Chuyi Zhou. 2) Fix BPF verifier's iterator convergence logic to use exact states comparison for convergence checks, from Eduard Zingerman, Andrii Nakryiko and Alexei Starovoitov. 3) Add BPF programmable net device where bpf_mprog defines the logic of its xmit routine. It can operate in L3 and L2 mode, from Daniel Borkmann and Nikolay Aleksandrov. 4) Batch of fixes for BPF per-CPU kptr and re-enable unit_size checking for global per-CPU allocator, from Hou Tao. 5) Fix libbpf which eagerly assumed that SHT_GNU_verdef ELF section was going to be present whenever a binary has SHT_GNU_versym section, from Andrii Nakryiko. 6) Fix BPF ringbuf correctness to fold smp_mb__before_atomic() into atomic_set_release(), from Paul E. McKenney. 7) Add a warning if NAPI callback missed xdp_do_flush() under CONFIG_DEBUG_NET which helps checking if drivers were missing the former, from Sebastian Andrzej Siewior. 8) Fix missed RCU read-lock in bpf_task_under_cgroup() which was throwing a warning under sleepable programs, from Yafang Shao. 9) Avoid unnecessary -EBUSY from htab_lock_bucket by disabling IRQ before checking map_locked, from Song Liu. 10) Make BPF CI linked_list failure test more robust, from Kumar Kartikeya Dwivedi. 11) Enable samples/bpf to be built as PIE in Fedora, from Viktor Malik. 12) Fix xsk starving when multiple xsk sockets were associated with a single xsk_buff_pool, from Albert Huang. 13) Clarify the signed modulo implementation for the BPF ISA standardization document that it uses truncated division, from Dave Thaler. 14) Improve BPF verifier's JEQ/JNE branch taken logic to also consider signed bounds knowledge, from Andrii Nakryiko. 15) Add an option to XDP selftests to use multi-buffer AF_XDP xdp_hw_metadata and mark used XDP programs as capable to use frags, from Larysa Zaremba. 16) Fix bpftool's BTF dumper wrt printing a pointer value and another one to fix struct_ops dump in an array, from Manu Bretelle. * tag 'for-netdev' of ssh://gitolite.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (51 commits) netkit: Remove explicit active/peer ptr initialization selftests/bpf: Fix selftests broken by mitigations=off samples/bpf: Allow building with custom bpftool samples/bpf: Fix passing LDFLAGS to libbpf samples/bpf: Allow building with custom CFLAGS/LDFLAGS bpf: Add more WARN_ON_ONCE checks for mismatched alloc and free selftests/bpf: Add selftests for netkit selftests/bpf: Add netlink helper library bpftool: Extend net dump with netkit progs bpftool: Implement link show support for netkit libbpf: Add link-based API for netkit tools: Sync if_link uapi header netkit, bpf: Add bpf programmable net device bpf: Improve JEQ/JNE branch taken logic bpf: Fold smp_mb__before_atomic() into atomic_set_release() bpf: Fix unnecessary -EBUSY from htab_lock_bucket xsk: Avoid starving the xsk further down the list bpf: print full verifier states on infinite loop detection selftests/bpf: test if state loops are detected in a tricky case bpf: correct loop detection for iterators convergence ... ==================== Link: https://lore.kernel.org/r/20231026150509.2824-1-daniel@iogearbox.net Signed-off-by: Jakub Kicinski <kuba@kernel.org> 
Daniel Borkmann says:

====================
pull-request: bpf-next 2023-10-26

We've added 51 non-merge commits during the last 10 day(s) which contain
a total of 75 files changed, 5037 insertions(+), 200 deletions(-).

The main changes are:

1) Add open-coded task, css_task and css iterator support.
   One of the use cases is customizable OOM victim selection via BPF,
   from Chuyi Zhou.

2) Fix BPF verifier's iterator convergence logic to use exact states
   comparison for convergence checks, from Eduard Zingerman,
   Andrii Nakryiko and Alexei Starovoitov.

3) Add BPF programmable net device where bpf_mprog defines the logic
   of its xmit routine. It can operate in L3 and L2 mode,
   from Daniel Borkmann and Nikolay Aleksandrov.

4) Batch of fixes for BPF per-CPU kptr and re-enable unit_size checking
   for global per-CPU allocator, from Hou Tao.

5) Fix libbpf which eagerly assumed that SHT_GNU_verdef ELF section
   was going to be present whenever a binary has SHT_GNU_versym section,
   from Andrii Nakryiko.

6) Fix BPF ringbuf correctness to fold smp_mb__before_atomic() into
   atomic_set_release(), from Paul E. McKenney.

7) Add a warning if NAPI callback missed xdp_do_flush() under
   CONFIG_DEBUG_NET which helps checking if drivers were missing
   the former, from Sebastian Andrzej Siewior.

8) Fix missed RCU read-lock in bpf_task_under_cgroup() which was throwing
   a warning under sleepable programs, from Yafang Shao.

9) Avoid unnecessary -EBUSY from htab_lock_bucket by disabling IRQ before
   checking map_locked, from Song Liu.

10) Make BPF CI linked_list failure test more robust,
    from Kumar Kartikeya Dwivedi.

11) Enable samples/bpf to be built as PIE in Fedora, from Viktor Malik.

12) Fix xsk starving when multiple xsk sockets were associated with
    a single xsk_buff_pool, from Albert Huang.

13) Clarify the signed modulo implementation for the BPF ISA standardization
    document that it uses truncated division, from Dave Thaler.

14) Improve BPF verifier's JEQ/JNE branch taken logic to also consider
    signed bounds knowledge, from Andrii Nakryiko.

15) Add an option to XDP selftests to use multi-buffer AF_XDP
    xdp_hw_metadata and mark used XDP programs as capable to use frags,
    from Larysa Zaremba.

16) Fix bpftool's BTF dumper wrt printing a pointer value and another
    one to fix struct_ops dump in an array, from Manu Bretelle.

* tag 'for-netdev' of ssh://gitolite.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (51 commits)
  netkit: Remove explicit active/peer ptr initialization
  selftests/bpf: Fix selftests broken by mitigations=off
  samples/bpf: Allow building with custom bpftool
  samples/bpf: Fix passing LDFLAGS to libbpf
  samples/bpf: Allow building with custom CFLAGS/LDFLAGS
  bpf: Add more WARN_ON_ONCE checks for mismatched alloc and free
  selftests/bpf: Add selftests for netkit
  selftests/bpf: Add netlink helper library
  bpftool: Extend net dump with netkit progs
  bpftool: Implement link show support for netkit
  libbpf: Add link-based API for netkit
  tools: Sync if_link uapi header
  netkit, bpf: Add bpf programmable net device
  bpf: Improve JEQ/JNE branch taken logic
  bpf: Fold smp_mb__before_atomic() into atomic_set_release()
  bpf: Fix unnecessary -EBUSY from htab_lock_bucket
  xsk: Avoid starving the xsk further down the list
  bpf: print full verifier states on infinite loop detection
  selftests/bpf: test if state loops are detected in a tricky case
  bpf: correct loop detection for iterators convergence
  ...
====================

Link: https://lore.kernel.org/r/20231026150509.2824-1-daniel@iogearbox.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
net: remove else after return in dev_prep_valid_name() 2023-10-24T20:02:59+00:00 Jakub Kicinski kuba@kernel.org 2023-10-23T15:23:46+00:00 ce4cfa2318afcd74cc41992e306a28fa04e5d484 Remove unnecessary else clauses after return. I copied this if / else construct from somewhere, it makes the code harder to read. Reviewed-by: Jiri Pirko <jiri@nvidia.com> Link: https://lore.kernel.org/r/20231023152346.3639749-7-kuba@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org> 
Remove unnecessary else clauses after return.
I copied this if / else construct from somewhere,
it makes the code harder to read.

Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Link: https://lore.kernel.org/r/20231023152346.3639749-7-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
net: remove dev_valid_name() check from __dev_alloc_name() 2023-10-24T20:02:58+00:00 Jakub Kicinski kuba@kernel.org 2023-10-23T15:23:45+00:00 70e1b14c1bcbbb0854311ff8bed6cf4db75d5f05 __dev_alloc_name() is only called by dev_prep_valid_name(), which already checks that name is valid. Reviewed-by: Jiri Pirko <jiri@nvidia.com> Link: https://lore.kernel.org/r/20231023152346.3639749-6-kuba@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org> 
__dev_alloc_name() is only called by dev_prep_valid_name(),
which already checks that name is valid.

Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Link: https://lore.kernel.org/r/20231023152346.3639749-6-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
net: trust the bitmap in __dev_alloc_name() 2023-10-24T20:02:58+00:00 Jakub Kicinski kuba@kernel.org 2023-10-23T15:23:44+00:00 7ad17b04dc7bdcdd1f85e460c38da55b0afa2422 Prior to restructuring __dev_alloc_name() handled both printf and non-printf names. In a clever attempt at code reuse it always prints the name into a buffer and checks if it's a duplicate. Trust the bitmap, and return an error if its full. This shrinks the possible ID space by one from 32K to 32K - 1, as previously the max value would have been tried as a valid ID. It seems very unlikely that anyone would care as we heard no requests to increase the max beyond 32k. Reviewed-by: Jiri Pirko <jiri@nvidia.com> Link: https://lore.kernel.org/r/20231023152346.3639749-5-kuba@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org> 
Prior to restructuring __dev_alloc_name() handled both printf
and non-printf names. In a clever attempt at code reuse it
always prints the name into a buffer and checks if it's
a duplicate.

Trust the bitmap, and return an error if its full.

This shrinks the possible ID space by one from 32K to 32K - 1,
as previously the max value would have been tried as a valid ID.
It seems very unlikely that anyone would care as we heard
no requests to increase the max beyond 32k.

Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Link: https://lore.kernel.org/r/20231023152346.3639749-5-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
net: reduce indentation of __dev_alloc_name() 2023-10-24T20:02:58+00:00 Jakub Kicinski kuba@kernel.org 2023-10-23T15:23:43+00:00 9a810468126c846299d867f73dd7053064c29be1 All callers of __dev_valid_name() go thru dev_prep_valid_name() which handles the non-printf case. Focus __dev_alloc_name() on the sprintf case, remove the indentation level. Minor functional change of returning -EINVAL if % is not found, which should now never happen. Reviewed-by: Jiri Pirko <jiri@nvidia.com> Link: https://lore.kernel.org/r/20231023152346.3639749-4-kuba@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org> 
All callers of __dev_valid_name() go thru dev_prep_valid_name()
which handles the non-printf case. Focus __dev_alloc_name() on
the sprintf case, remove the indentation level.

Minor functional change of returning -EINVAL if % is not found,
which should now never happen.

Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Link: https://lore.kernel.org/r/20231023152346.3639749-4-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
net: make dev_alloc_name() call dev_prep_valid_name() 2023-10-24T20:02:58+00:00 Jakub Kicinski kuba@kernel.org 2023-10-23T15:23:42+00:00 556c755a4d8143007c745b6ad894611a04173b53 __dev_alloc_name() handles both the sprintf and non-sprintf target names. This complicates the code. dev_prep_valid_name() already handles the non-sprintf case, before calling __dev_alloc_name(), make the only other caller also go thru dev_prep_valid_name(). This way we can drop the non-sprintf handling in __dev_alloc_name() in one of the next changes. commit 55a5ec9b7710 ("Revert "net: core: dev_get_valid_name is now the same as dev_alloc_name_ns"") and commit 029b6d140550 ("Revert "net: core: maybe return -EEXIST in __dev_alloc_name"") tell us that we can't start returning -EEXIST from dev_alloc_name() on name duplicates. Bite the bullet and pass the expected errno to dev_prep_valid_name(). dev_prep_valid_name() must now propagate out the allocated id for printf names. Reviewed-by: Jiri Pirko <jiri@nvidia.com> Link: https://lore.kernel.org/r/20231023152346.3639749-3-kuba@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org> 
__dev_alloc_name() handles both the sprintf and non-sprintf
target names. This complicates the code.

dev_prep_valid_name() already handles the non-sprintf case,
before calling __dev_alloc_name(), make the only other caller
also go thru dev_prep_valid_name(). This way we can drop
the non-sprintf handling in __dev_alloc_name() in one of
the next changes.

commit 55a5ec9b7710 ("Revert "net: core: dev_get_valid_name is now the same as dev_alloc_name_ns"") and
commit 029b6d140550 ("Revert "net: core: maybe return -EEXIST in __dev_alloc_name"")
tell us that we can't start returning -EEXIST from dev_alloc_name()
on name duplicates. Bite the bullet and pass the expected errno to
dev_prep_valid_name().

dev_prep_valid_name() must now propagate out the allocated id
for printf names.

Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Link: https://lore.kernel.org/r/20231023152346.3639749-3-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
net: don't use input buffer of __dev_alloc_name() as a scratch space 2023-10-24T20:02:58+00:00 Jakub Kicinski kuba@kernel.org 2023-10-23T15:23:41+00:00 bd07063dd11f6fda903802a5868960be3690d327 Callers of __dev_alloc_name() want to pass dev->name as the output buffer. Make __dev_alloc_name() not clobber that buffer on failure, and remove the workarounds in callers. dev_alloc_name_ns() is now completely unnecessary. The extra strscpy() added here will be gone by the end of the patch series. Reviewed-by: Jiri Pirko <jiri@nvidia.com> Link: https://lore.kernel.org/r/20231023152346.3639749-2-kuba@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org> 
Callers of __dev_alloc_name() want to pass dev->name as
the output buffer. Make __dev_alloc_name() not clobber
that buffer on failure, and remove the workarounds
in callers.

dev_alloc_name_ns() is now completely unnecessary.

The extra strscpy() added here will be gone by the end
of the patch series.

Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Link: https://lore.kernel.org/r/20231023152346.3639749-2-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2023-10-19T20:29:01+00:00 Jakub Kicinski kuba@kernel.org 2023-10-19T20:13:03+00:00 041c3466f39d7073bbc7fb91c4e5d14170d5eb08 Cross-merge networking fixes after downstream PR. net/mac80211/key.c 02e0e426a2fb ("wifi: mac80211: fix error path key leak") 2a8b665e6bcc ("wifi: mac80211: remove key_mtx") 7d6904bf26b9 ("Merge wireless into wireless-next") https://lore.kernel.org/all/20231012113648.46eea5ec@canb.auug.org.au/ Adjacent changes: drivers/net/ethernet/ti/Kconfig a602ee3176a8 ("net: ethernet: ti: Fix mixed module-builtin object") 98bdeae9502b ("net: cpmac: remove driver to prepare for platform removal") Signed-off-by: Jakub Kicinski <kuba@kernel.org> 
Cross-merge networking fixes after downstream PR.

net/mac80211/key.c
  02e0e426a2fb ("wifi: mac80211: fix error path key leak")
  2a8b665e6bcc ("wifi: mac80211: remove key_mtx")
  7d6904bf26b9 ("Merge wireless into wireless-next")
https://lore.kernel.org/all/20231012113648.46eea5ec@canb.auug.org.au/

Adjacent changes:

drivers/net/ethernet/ti/Kconfig
  a602ee3176a8 ("net: ethernet: ti: Fix mixed module-builtin object")
  98bdeae9502b ("net: cpmac: remove driver to prepare for platform removal")

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
net: move altnames together with the netdevice 2023-10-19T13:51:16+00:00 Jakub Kicinski kuba@kernel.org 2023-10-18T01:38:16+00:00 8e15aee621618a3ee3abecaf1fd8c1428098b7ef The altname nodes are currently not moved to the new netns when netdevice itself moves: [ ~]# ip netns add test [ ~]# ip -netns test link add name eth0 type dummy [ ~]# ip -netns test link property add dev eth0 altname some-name [ ~]# ip -netns test link show dev some-name 2: eth0: <BROADCAST,NOARP> mtu 1500 qdisc noop state DOWN mode DEFAULT group default qlen 1000 link/ether 1e:67:ed:19:3d:24 brd ff:ff:ff:ff:ff:ff altname some-name [ ~]# ip -netns test link set dev eth0 netns 1 [ ~]# ip link ... 3: eth0: <BROADCAST,NOARP> mtu 1500 qdisc noop state DOWN mode DEFAULT group default qlen 1000 link/ether 02:40:88:62:ec:b8 brd ff:ff:ff:ff:ff:ff altname some-name [ ~]# ip li show dev some-name Device "some-name" does not exist. Remove them from the hash table when device is unlisted and add back when listed again. Fixes: 36fbf1e52bd3 ("net: rtnetlink: add linkprop commands to add and delete alternative ifnames") Reviewed-by: Jiri Pirko <jiri@nvidia.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Paolo Abeni <pabeni@redhat.com> 
The altname nodes are currently not moved to the new netns
when netdevice itself moves:

  [ ~]# ip netns add test
  [ ~]# ip -netns test link add name eth0 type dummy
  [ ~]# ip -netns test link property add dev eth0 altname some-name
  [ ~]# ip -netns test link show dev some-name
  2: eth0: <BROADCAST,NOARP> mtu 1500 qdisc noop state DOWN mode DEFAULT group default qlen 1000
      link/ether 1e:67:ed:19:3d:24 brd ff:ff:ff:ff:ff:ff
      altname some-name
  [ ~]# ip -netns test link set dev eth0 netns 1
  [ ~]# ip link
  ...
  3: eth0: <BROADCAST,NOARP> mtu 1500 qdisc noop state DOWN mode DEFAULT group default qlen 1000
      link/ether 02:40:88:62:ec:b8 brd ff:ff:ff:ff:ff:ff
      altname some-name
  [ ~]# ip li show dev some-name
  Device "some-name" does not exist.

Remove them from the hash table when device is unlisted
and add back when listed again.

Fixes: 36fbf1e52bd3 ("net: rtnetlink: add linkprop commands to add and delete alternative ifnames")
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>