In arraymap.c: In bpf_array_map_seq_start() and bpf_array_map_seq_next() cast return values from the __percpu address space to the generic address space via uintptr_t [1]. Correct the declaration of pptr pointer in __bpf_array_map_seq_show() to void __percpu * and cast the value from the generic address space to the __percpu address space via uintptr_t [1]. In hashtab.c: Assign the return value from bpf_mem_cache_alloc() to void pointer and cast the value to void __percpu ** (void pointer to percpu void pointer) before dereferencing. In memalloc.c: Explicitly declare __percpu variables. Cast obj to void __percpu **. In helpers.c: Cast ptr in BPF_CALL_1 and BPF_CALL_2 from generic address space to __percpu address space via const uintptr_t [1]. Found by GCC's named address space checks. There were no changes in the resulting object files. [1] https://sparse.docs.kernel.org/en/latest/annotations.html#address-space-name Signed-off-by: Uros Bizjak <ubizjak@xxxxxxxxx> Cc: Alexei Starovoitov <ast@xxxxxxxxxx> Cc: Daniel Borkmann <daniel@xxxxxxxxxxxxx> Cc: Andrii Nakryiko <andrii@xxxxxxxxxx> Cc: Martin KaFai Lau <martin.lau@xxxxxxxxx> Cc: Eduard Zingerman <eddyz87@xxxxxxxxx> Cc: Song Liu <song@xxxxxxxxxx> Cc: Yonghong Song <yonghong.song@xxxxxxxxx> Cc: John Fastabend <john.fastabend@xxxxxxxxx> Cc: KP Singh <kpsingh@xxxxxxxxxx> Cc: Stanislav Fomichev <sdf@xxxxxxxxxxx> Cc: Hao Luo <haoluo@xxxxxxxxxx> Cc: Jiri Olsa <jolsa@xxxxxxxxxx> --- v2: - cast return values from the __percpu address space to the generic address space in bpf_array_map_seq_{start,next}(). - correct the declaration of pptr pointer in __bpf_array_map_seq_show() to void __percpu * --- kernel/bpf/arraymap.c | 8 ++++---- kernel/bpf/hashtab.c | 9 +++++---- kernel/bpf/helpers.c | 4 ++-- kernel/bpf/memalloc.c | 12 ++++++------ 4 files changed, 17 insertions(+), 16 deletions(-) diff --git a/kernel/bpf/arraymap.c b/kernel/bpf/arraymap.c index 188e3c2effb2..a43e62e2a8bb 100644 --- a/kernel/bpf/arraymap.c +++ b/kernel/bpf/arraymap.c @@ -600,7 +600,7 @@ static void *bpf_array_map_seq_start(struct seq_file *seq, loff_t *pos) array = container_of(map, struct bpf_array, map); index = info->index & array->index_mask; if (info->percpu_value_buf) - return array->pptrs[index]; + return (void *)(uintptr_t)array->pptrs[index]; return array_map_elem_ptr(array, index); } @@ -619,7 +619,7 @@ static void *bpf_array_map_seq_next(struct seq_file *seq, void *v, loff_t *pos) array = container_of(map, struct bpf_array, map); index = info->index & array->index_mask; if (info->percpu_value_buf) - return array->pptrs[index]; + return (void *)(uintptr_t)array->pptrs[index]; return array_map_elem_ptr(array, index); } @@ -632,7 +632,7 @@ static int __bpf_array_map_seq_show(struct seq_file *seq, void *v) struct bpf_iter_meta meta; struct bpf_prog *prog; int off = 0, cpu = 0; - void __percpu **pptr; + void __percpu *pptr; u32 size; meta.seq = seq; @@ -648,7 +648,7 @@ static int __bpf_array_map_seq_show(struct seq_file *seq, void *v) if (!info->percpu_value_buf) { ctx.value = v; } else { - pptr = v; + pptr = (void __percpu *)(uintptr_t)v; size = array->elem_size; for_each_possible_cpu(cpu) { copy_map_value_long(map, info->percpu_value_buf + off, diff --git a/kernel/bpf/hashtab.c b/kernel/bpf/hashtab.c index be1f64c20125..45c7195b65ba 100644 --- a/kernel/bpf/hashtab.c +++ b/kernel/bpf/hashtab.c @@ -1049,14 +1049,15 @@ static struct htab_elem *alloc_htab_elem(struct bpf_htab *htab, void *key, pptr = htab_elem_get_ptr(l_new, key_size); } else { /* alloc_percpu zero-fills */ - pptr = bpf_mem_cache_alloc(&htab->pcpu_ma); - if (!pptr) { + void *ptr = bpf_mem_cache_alloc(&htab->pcpu_ma); + + if (!ptr) { bpf_mem_cache_free(&htab->ma, l_new); l_new = ERR_PTR(-ENOMEM); goto dec_count; } - l_new->ptr_to_pptr = pptr; - pptr = *(void **)pptr; + l_new->ptr_to_pptr = ptr; + pptr = *(void __percpu **)ptr; } pcpu_init_value(htab, pptr, value, onallcpus); diff --git a/kernel/bpf/helpers.c b/kernel/bpf/helpers.c index d02ae323996b..dd7529153146 100644 --- a/kernel/bpf/helpers.c +++ b/kernel/bpf/helpers.c @@ -715,7 +715,7 @@ BPF_CALL_2(bpf_per_cpu_ptr, const void *, ptr, u32, cpu) if (cpu >= nr_cpu_ids) return (unsigned long)NULL; - return (unsigned long)per_cpu_ptr((const void __percpu *)ptr, cpu); + return (unsigned long)per_cpu_ptr((const void __percpu *)(const uintptr_t)ptr, cpu); } const struct bpf_func_proto bpf_per_cpu_ptr_proto = { @@ -728,7 +728,7 @@ const struct bpf_func_proto bpf_per_cpu_ptr_proto = { BPF_CALL_1(bpf_this_cpu_ptr, const void *, percpu_ptr) { - return (unsigned long)this_cpu_ptr((const void __percpu *)percpu_ptr); + return (unsigned long)this_cpu_ptr((const void __percpu *)(const uintptr_t)percpu_ptr); } const struct bpf_func_proto bpf_this_cpu_ptr_proto = { diff --git a/kernel/bpf/memalloc.c b/kernel/bpf/memalloc.c index dec892ded031..b3858a76e0b3 100644 --- a/kernel/bpf/memalloc.c +++ b/kernel/bpf/memalloc.c @@ -138,8 +138,8 @@ static struct llist_node notrace *__llist_del_first(struct llist_head *head) static void *__alloc(struct bpf_mem_cache *c, int node, gfp_t flags) { if (c->percpu_size) { - void **obj = kmalloc_node(c->percpu_size, flags, node); - void *pptr = __alloc_percpu_gfp(c->unit_size, 8, flags); + void __percpu **obj = kmalloc_node(c->percpu_size, flags, node); + void __percpu *pptr = __alloc_percpu_gfp(c->unit_size, 8, flags); if (!obj || !pptr) { free_percpu(pptr); @@ -253,7 +253,7 @@ static void alloc_bulk(struct bpf_mem_cache *c, int cnt, int node, bool atomic) static void free_one(void *obj, bool percpu) { if (percpu) { - free_percpu(((void **)obj)[1]); + free_percpu(((void __percpu **)obj)[1]); kfree(obj); return; } @@ -509,8 +509,8 @@ static void prefill_mem_cache(struct bpf_mem_cache *c, int cpu) */ int bpf_mem_alloc_init(struct bpf_mem_alloc *ma, int size, bool percpu) { - struct bpf_mem_caches *cc, __percpu *pcc; - struct bpf_mem_cache *c, __percpu *pc; + struct bpf_mem_caches *cc; struct bpf_mem_caches __percpu *pcc; + struct bpf_mem_cache *c; struct bpf_mem_cache __percpu *pc; struct obj_cgroup *objcg = NULL; int cpu, i, unit_size, percpu_size = 0; @@ -591,7 +591,7 @@ int bpf_mem_alloc_percpu_init(struct bpf_mem_alloc *ma, struct obj_cgroup *objcg int bpf_mem_alloc_percpu_unit_init(struct bpf_mem_alloc *ma, int size) { - struct bpf_mem_caches *cc, __percpu *pcc; + struct bpf_mem_caches *cc; struct bpf_mem_caches __percpu *pcc; int cpu, i, unit_size, percpu_size; struct obj_cgroup *objcg; struct bpf_mem_cache *c; -- 2.46.0
