From: Heiko Carstens <[email protected]> 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 <[email protected]> --- samples/seccomp/bpf-helper.h | 15 ++++++++++----- 1 file changed, 10 insertions(+), 5 deletions(-) diff --git a/samples/seccomp/bpf-helper.h b/samples/seccomp/bpf-helper.h index 643279d..38ee70f 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 { -- 1.7.11.4 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
