This series continues the migration to sockopt_t, as described in [1]. do_ip_getsockopt() and do_ipv6_getsockopt() are the last two switches still taking a sockptr_t pair, and everything they forward to now takes a sockopt_t, so convert them both.
Patch 1 settles what a negative optlen means on SOL_IPV6 before the conversion makes it matter. do_ip_getsockopt() rejects it, but do_ipv6_getsockopt() never has, and the int options answer it as 4. Treat it as 4, as David Laight suggested, instead of failing callers that rely on it. Patch 2 fixes a latent bug in sockopt_expand_out() [2] itself: it caps the expansion at INT_MAX, but iov_iter_revert() refuses to unroll past the smaller MAX_RW_COUNT. MCAST_MSFILTER has to move before the switches above it. It is the last option with the quirk sockopt_expand_out() was added for [2]: optlen only covers the fixed part, and the real reply size comes from the gf_numsrc field inside it. Patches 3 and 4 convert it on both families, and store the reply length only after the final copy succeeds, so a copy failure can't report a changed optlen. Patches 5 and 6 convert the switches themselves. Each wrapper keeps its __user prototype and builds the sockopt_t, so the proto layer is untouched. ipv6_getsockopt() cannot use sockopt_init_user(), which rejects a negative optlen, so patch 6 moves the clamp of patch 1 up there and builds the sockopt_t after it. Patch 7 grows the selftest with an ip and an ipv6 fixture, pinning the returned length, errno and reply bytes. The temporary sockptr_t-to-sockopt_t glue can go away once the higher level callers take sockopt_t too. For now, the series keeps the proto callbacks unchanged and converts only the leaf helpers. Link: https://lore.kernel.org/all/[email protected]/ [1] Link: https://lore.kernel.org/all/[email protected]/ [2] To: David Ahern <[email protected]> To: Ido Schimmel <[email protected]> To: David S. Miller <[email protected]> To: Eric Dumazet <[email protected]> To: Jakub Kicinski <[email protected]> To: Paolo Abeni <[email protected]> To: Simon Horman <[email protected]> To: Alexei Starovoitov <[email protected]> To: Daniel Borkmann <[email protected]> To: Andrii Nakryiko <[email protected]> To: Eduard Zingerman <[email protected]> To: Kumar Kartikeya Dwivedi <[email protected]> To: Martin KaFai Lau <[email protected]> To: Song Liu <[email protected]> To: Yonghong Song <[email protected]> To: Jiri Olsa <[email protected]> To: Emil Tsalapatis <[email protected]> To: Ihor Solodrai <[email protected]> To: John Fastabend <[email protected]> To: Stanislav Fomichev <[email protected]> To: Shuah Khan <[email protected]> Cc: [email protected] Cc: [email protected] Cc: [email protected] Cc: [email protected] To: Stanislav Fomichev <[email protected]> Cc: [email protected] Signed-off-by: Breno Leitao <[email protected]> --- Changes in v2: - Treat a negative optlen as 4 instead of rejecting it with -EINVAL as v1 did, per David Laight and Stanislav Fomichev. - Fix sashiko findings - Link to v1: https://patch.msgid.link/[email protected] --- Breno Leitao (7): ipv6: treat a negative optlen as 4 in do_ipv6_getsockopt() net: cap sockopt_expand_out() at MAX_RW_COUNT ipv6: mcast: convert ip6_mc_msfget() to sockopt_t ipv4: igmp: convert ip_mc_gsfget() to sockopt_t ipv4: convert do_ip_getsockopt() to sockopt_t ipv6: convert do_ipv6_getsockopt() to sockopt_t selftests: net: getsockopt_iter: cover ip and ipv6 include/linux/igmp.h | 2 +- include/linux/mroute.h | 4 +- include/linux/mroute6.h | 5 +- include/linux/net.h | 27 +- include/net/ip.h | 3 +- include/net/ipv6.h | 4 +- net/core/filter.c | 36 ++- net/ipv4/igmp.c | 23 +- net/ipv4/ip_sockglue.c | 118 ++++----- net/ipv4/ipmr.c | 11 +- net/ipv6/ip6mr.c | 13 +- net/ipv6/ipv6_sockglue.c | 117 +++++---- net/ipv6/mcast.c | 19 +- tools/testing/selftests/net/getsockopt_iter.c | 359 ++++++++++++++++++++++++++ 14 files changed, 577 insertions(+), 164 deletions(-) --- base-commit: aac26bee2287c88af5be5a5ff96d783b19a28790 change-id: 20260924-sockopt_expand_out_v2-ee4bc7ba4cea Best regards, -- Breno Leitao <[email protected]>
