RE: [PATCH 1/2] audit: Add syscall return code handling for compat task

Sent: 14 April 2021 09:02 When 32-bit userspace application is running on 64-bit kernel, the 32-bit syscall return code would be changed from u32 to u64 in regs_return_value and then changed to s64. Hence the negative return code recorded by audit would end up being a big positive number like below. type=SYSCALL msg=audit(1611110715.887:582): arch=40000028 syscall=322 success=yes exit=4294967283 This patch forces the u32->s32->s64 for compat tasks. Signed-off-by: He Zhe <zhe.he(a)windriver.com&gt; --- include/linux/audit.h | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/include/linux/audit.h b/include/linux/audit.h index 82b7c1116a85..32cb853f3029 100644 --- a/include/linux/audit.h +++ b/include/linux/audit.h @@ -334,7 +334,9 @@ static inline void audit_syscall_exit(void *pt_regs) { if (unlikely(audit_context())) { int success = is_syscall_success(pt_regs); - long return_code = regs_return_value(pt_regs); + long return_code = is_compat_task() ?

+ (s64)(s32)regs_return_value(pt_regs) : + regs_return_value(pt_regs); __audit_syscall_exit(success, return_code); } -- 2.17.1