diff options
| author | Heiko Carstens <heiko.carstens@de.ibm.com> | 2012-07-31 16:15:36 +0200 |
|---|---|---|
| committer | James Morris <james.l.morris@oracle.com> | 2012-08-03 14:27:40 +1000 |
| commit | de4bb3b9c788ea5504dfe094e34d831e8395075d (patch) | |
| tree | e957a72a3c695d442838b2fef184da8ad5acc193 | |
| parent | 663728418e3494f8e4a82f5d1b2f23c22d11be35 (diff) | |
| download | lwn-de4bb3b9c788ea5504dfe094e34d831e8395075d.tar.gz lwn-de4bb3b9c788ea5504dfe094e34d831e8395075d.zip | |
samples/seccomp: fix endianness bug in LO_ARG define
The LO_ARG define needs to consider endianness also for 32 bit builds.
The "bpf_fancy" test case didn't work on s390 in 32 bit and compat mode
because the LO_ARG define resulted in a BPF program which read the upper
halve of the 64 bit system call arguments instead of the lower halves.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Acked-by: Kees Cook <keescook@chromium.org>
Signed-off-by: James Morris <james.l.morris@oracle.com>
| -rw-r--r-- | samples/seccomp/bpf-helper.h | 15 |
1 files changed, 10 insertions, 5 deletions
diff --git a/samples/seccomp/bpf-helper.h b/samples/seccomp/bpf-helper.h index 643279dd30fb..38ee70f3cd5b 100644 --- a/samples/seccomp/bpf-helper.h +++ b/samples/seccomp/bpf-helper.h @@ -59,6 +59,16 @@ void seccomp_bpf_print(struct sock_filter *filter, size_t count); #define FIND_LABEL(labels, label) seccomp_bpf_label((labels), #label) #define EXPAND(...) __VA_ARGS__ + +/* Ensure that we load the logically correct offset. */ +#if __BYTE_ORDER == __LITTLE_ENDIAN +#define LO_ARG(idx) offsetof(struct seccomp_data, args[(idx)]) +#elif __BYTE_ORDER == __BIG_ENDIAN +#define LO_ARG(idx) offsetof(struct seccomp_data, args[(idx)]) + sizeof(__u32) +#else +#error "Unknown endianness" +#endif + /* Map all width-sensitive operations */ #if __BITS_PER_LONG == 32 @@ -70,21 +80,16 @@ void seccomp_bpf_print(struct sock_filter *filter, size_t count); #define JLE(x, jt) JLE32(x, EXPAND(jt)) #define JA(x, jt) JA32(x, EXPAND(jt)) #define ARG(i) ARG_32(i) -#define LO_ARG(idx) offsetof(struct seccomp_data, args[(idx)]) #elif __BITS_PER_LONG == 64 /* Ensure that we load the logically correct offset. */ #if __BYTE_ORDER == __LITTLE_ENDIAN #define ENDIAN(_lo, _hi) _lo, _hi -#define LO_ARG(idx) offsetof(struct seccomp_data, args[(idx)]) #define HI_ARG(idx) offsetof(struct seccomp_data, args[(idx)]) + sizeof(__u32) #elif __BYTE_ORDER == __BIG_ENDIAN #define ENDIAN(_lo, _hi) _hi, _lo -#define LO_ARG(idx) offsetof(struct seccomp_data, args[(idx)]) + sizeof(__u32) #define HI_ARG(idx) offsetof(struct seccomp_data, args[(idx)]) -#else -#error "Unknown endianness" #endif union arg64 { |