From 162cf592b577cccf04515100563e819d9eba5c4a Mon Sep 17 00:00:00 2001 From: Fernando Fernandez Mancera Date: Wed, 28 Oct 2026 23:53:50 +0100 Subject: [PATCH] net/smc: fix limit_smc_hs sysctl on big-endian architecture net->smc.limit_smc_hs is a bool, but its sysctl entry uses proc_dointvec_minmax() with .maxlen = sizeof(int), so the handler accesses four bytes at the address of a one-byte field. On little-endian this works with the extra bytes being written in struct padding. On big-endian (tested on s390x) the bool sits at the most significant byte of the int therefore the bool stays false and the "1" goes into padding. The sysctl reads back 1 but SMC sockets created afterwards see limit_smc_hs as disabled. Fix this by using proc_dobool() handler and adjust the maxlen to the right value. Fixes: f8406a2fd279 ("net/smc: add sysctl for smc_limit_hs") Signed-off-by: Fernando Fernandez Mancera Link: https://patch.msgid.link/20261028225350.3753-1-fmancera@suse.de Signed-off-by: Jakub Kicinski --- net/smc/smc_sysctl.c | 6 ++---- 1 file changed, 2 insertions(+), 4 deletions(-) diff --git a/net/smc/smc_sysctl.c b/net/smc/smc_sysctl.c index 09dad48337f6..f58cf256f61a 100644 --- a/net/smc/smc_sysctl.c +++ b/net/smc/smc_sysctl.c @@ -160,11 +160,9 @@ static const struct ctl_table smc_table[] = { { .procname = "limit_smc_hs", .data = &init_net.smc.limit_smc_hs, - .maxlen = sizeof(int), + .maxlen = sizeof(bool), .mode = 0644, - .proc_handler = proc_dointvec_minmax, - .extra1 = SYSCTL_ZERO, - .extra2 = SYSCTL_ONE, + .proc_handler = proc_dobool, }, { .procname = "smcr_max_send_wr",