diff options
| author | Tw <tw19881113@gmail.com> | 2026-08-28 08:34:10 +0800 |
|---|---|---|
| committer | Andrii Nakryiko <andrii@kernel.org> | 2026-08-28 10:28:04 -0700 |
| commit | cd35e1b10182c42b4ae31ee49119463b17d8ba7f (patch) | |
| tree | f3414d087af2ebcc7af8855c0c20afc61b259771 /tools/lib | |
| parent | 5e875ae9e9ffd5c76c6bdf8982f99de340dd46af (diff) | |
| download | linux-next-cd35e1b10182c42b4ae31ee49119463b17d8ba7f.tar.gz linux-next-cd35e1b10182c42b4ae31ee49119463b17d8ba7f.zip | |
libbpf: Fix for the potential undefined behavior due to shifting
When compiling libbpf with sanitation, ubsan will report the following:
```
left shift of 1 by 31 places cannot be represented in type 'int'
```
This may lead to undefined behavior according to the compiler implementation,
let's fix it by casting to unsigned counterpart before shifting.
Signed-off-by: Tan Wei <tw19881113@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20260828003448.1684064-1-tw19881113@gmail.com
Diffstat (limited to 'tools/lib')
| -rw-r--r-- | tools/lib/bpf/libbpf.c | 2 | ||||
| -rw-r--r-- | tools/lib/bpf/libbpf_internal.h | 4 |
2 files changed, 3 insertions, 3 deletions
diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c index b749c01742ee..f09cbfd8e729 100644 --- a/tools/lib/bpf/libbpf.c +++ b/tools/lib/bpf/libbpf.c @@ -11738,7 +11738,7 @@ static int perf_event_open_probe(bool uprobe, bool retprobe, const char *name, errstr(bit)); return bit; } - attr.config |= 1 << bit; + attr.config |= 1ULL << bit; } attr.size = attr_sz; attr.type = type; diff --git a/tools/lib/bpf/libbpf_internal.h b/tools/lib/bpf/libbpf_internal.h index 4c46d34fc055..cb4d96233844 100644 --- a/tools/lib/bpf/libbpf_internal.h +++ b/tools/lib/bpf/libbpf_internal.h @@ -77,7 +77,7 @@ #define JUMPTABLES_SEC ".jumptables" #define BTF_INFO_ENC(kind, kind_flag, vlen) \ - ((!!(kind_flag) << 31) | ((kind) << 24) | ((vlen) & BTF_MAX_VLEN)) + (((__u32)(!!(kind_flag)) << 31) | ((kind) << 24) | ((vlen) & BTF_MAX_VLEN)) #define BTF_TYPE_ENC(name, info, size_or_type) (name), (info), (size_or_type) #define BTF_INT_ENC(encoding, bits_offset, nr_bits) \ ((encoding) << 24 | (bits_offset) << 16 | (nr_bits)) @@ -259,7 +259,7 @@ static inline enum btf_func_linkage btf_func_linkage(const struct btf_type *t) static inline __u32 btf_type_info(int kind, int vlen, int kflag) { - return (kflag << 31) | (kind << 24) | vlen; + return ((__u32)kflag << 31) | (kind << 24) | vlen; } enum map_def_parts { |