6.6-stable review patch. If anyone has any objections, please let me know.
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From: Mohammad Shehar Yaar Tausif sheharyaar48@gmail.com
[ Upstream commit af253aef183a31ce62d2e39fc520b0ebfb562bb9 ]
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 andrii@kernel.org Tested-by: Christian Kujau lists@nerdbynature.de Signed-off-by: Mohammad Shehar Yaar Tausif sheharyaar48@gmail.com Signed-off-by: Vlastimil Babka vbabka@suse.cz Link: https://lore.kernel.org/r/20240710100521.15061-2-vbabka@suse.cz Signed-off-by: Alexei Starovoitov ast@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- 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 146824cc96893..e8d02212da703 100644 --- a/kernel/bpf/bpf_local_storage.c +++ b/kernel/bpf/bpf_local_storage.c @@ -808,8 +808,8 @@ 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;