From af253aef183a31ce62d2e39fc520b0ebfb562bb9 Mon Sep 17 00:00:00 2001 From: Mohammad Shehar Yaar Tausif Date: Wed, 10 Jul 2024 12:05:22 +0200 Subject: [PATCH] bpf: fix order of args in call to bpf_map_kvcalloc The original function call passed size of smap->bucket before the number of buckets which raises the error 'calloc-transposed-args' on compilation. Vlastimil Babka added: The order of parameters can be traced back all the way to 6ac99e8f23d4 ("bpf: Introduce bpf sk local storage") accross several refactorings, and that's why the commit is used as a Fixes: tag. In v6.10-rc1, a different commit 2c321f3f70bc ("mm: change inlined allocation helpers to account at the call site") however exposed the order of args in a way that gcc-14 has enough visibility to start warning about it, because (in !CONFIG_MEMCG case) bpf_map_kvcalloc is then a macro alias for kvcalloc instead of a static inline wrapper. To sum up the warning happens when the following conditions are all met: - gcc-14 is used (didn't see it with gcc-13) - commit 2c321f3f70bc is present - CONFIG_MEMCG is not enabled in .config - CONFIG_WERROR turns this from a compiler warning to error Fixes: 6ac99e8f23d4 ("bpf: Introduce bpf sk local storage") Reviewed-by: Andrii Nakryiko Tested-by: Christian Kujau Signed-off-by: Mohammad Shehar Yaar Tausif Signed-off-by: Vlastimil Babka Link: https://lore.kernel.org/r/20240710100521.15061-2-vbabka@suse.cz Signed-off-by: Alexei Starovoitov --- kernel/bpf/bpf_local_storage.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/kernel/bpf/bpf_local_storage.c b/kernel/bpf/bpf_local_storage.c index 976cb258a0ed..c938dea5ddbf 100644 --- a/kernel/bpf/bpf_local_storage.c +++ b/kernel/bpf/bpf_local_storage.c @@ -782,8 +782,8 @@ bpf_local_storage_map_alloc(union bpf_attr *attr, nbuckets = max_t(u32, 2, nbuckets); smap->bucket_log = ilog2(nbuckets); - smap->buckets = bpf_map_kvcalloc(&smap->map, sizeof(*smap->buckets), - nbuckets, GFP_USER | __GFP_NOWARN); + smap->buckets = bpf_map_kvcalloc(&smap->map, nbuckets, + sizeof(*smap->buckets), GFP_USER | __GFP_NOWARN); if (!smap->buckets) { err = -ENOMEM; goto free_smap;