Re: [RFC] [PATCH] audit: log 32-bit socketcalls

On Thu, Jan 12, 2017 at 7:36 AM, Richard Guy Briggs <rgb(a)redhat.com&gt; wrote: > 32-bit socketcalls were not being logged by audit on x86_64 systems. > Log them. > > See: https://github.com/linux-audit/audit-kernel/issues/14 > > Signed-off-by: Richard Guy Briggs <rgb(a)redhat.com&gt; > --- > net/compat.c | 18 ++++++++++++++++-- > 1 files changed, 16 insertions(+), 2 deletions(-) You should CC netdev on this patch; I'd also mention that you are simply duplicating the normal socketcall() auditing in the compat version (the only real difference being the argument size handling workaround).

> diff --git a/net/compat.c b/net/compat.c > index 1cd2ec0..86cacab 100644 > --- a/net/compat.c > +++ b/net/compat.c > @@ -22,6 +22,7 @@ > #include <linux/filter.h> > #include <linux/compat.h> > #include <linux/security.h> > +#include <linux/audit.h> > #include <linux/export.h> > > #include <net/scm.h> > @@ -781,14 +782,27 @@ COMPAT_SYSCALL_DEFINE5(recvmmsg, int, fd, struct compat_mmsghdr __user *, mmsg, > > COMPAT_SYSCALL_DEFINE2(socketcall, int, call, u32 __user *, args) > { > + unsigned int len, i; > int ret; > - u32 a[6]; > + u32 a[AUDITSC_ARGS]; > + unsigned long aa[AUDITSC_ARGS]; > u32 a0, a1; > > if (call < SYS_SOCKET || call > SYS_SENDMMSG) > return -EINVAL; > - if (copy_from_user(a, args, nas[call])) > + len = nas[call]; > + if (len > sizeof(a)) > + return -EINVAL; > + > + if (copy_from_user(a, args, len)) > return -EFAULT; > + > + for (i=0; i < len/sizeof(a[0]); i++) > + aa[i] = (unsigned long)a[i]; It will be interesting to see if you get push back on this loop outside of audit_socketcall(); folks may want to see it wrapped up inside a audit_socketcall_compat() (or similar) function so it isn't needlessly called in a number of cases. However, considering it is compat code, and not the common case it may be okay.

> + ret = audit_socketcall(len/sizeof(a[0]), aa); > + if (ret) > + return ret; > + > a0 = a[0]; > a1 = a[1]; > > -- > 1.7.1 -- paul moore www.paul-moore.com