git: 971cb62e0b23 - stable/13 - cpuset: Byte swap cpuset for compat32 on big endian architectures
- Go to: [ bottom of page ] [ top of archives ] [ this month ]
Date: Mon, 23 May 2022 22:11:38 UTC
The branch stable/13 has been updated by jhibbits:
URL: https://cgit.FreeBSD.org/src/commit/?id=971cb62e0b23f0a962f3348d82e70b331fe41268
commit 971cb62e0b23f0a962f3348d82e70b331fe41268
Author: Justin Hibbits <jhibbits@FreeBSD.org>
AuthorDate: 2022-05-12 20:38:22 +0000
Commit: Justin Hibbits <jhibbits@FreeBSD.org>
CommitDate: 2022-05-23 22:11:21 +0000
cpuset: Byte swap cpuset for compat32 on big endian architectures
Summary:
BITSET uses long as its basic underlying type, which is dependent on the
compile type, meaning on 32-bit builds the basic type is 32 bits, but on
64-bit builds it's 64 bits. On little endian architectures this doesn't
matter, because the LSB is always at the low bit, so the words get
effectively concatenated moving between 32-bit and 64-bit, but on
big-endian architectures it throws a wrench in, as setting bit 0 in
32-bit mode is equivalent to setting bit 32 in 64-bit mode. To
demonstrate:
32-bit mode:
BIT_SET(foo, 0): 0x00000001
64-bit sees: 0x0000000100000000
cpuset is the only system interface that uses bitsets, so solve this
by swapping the integer sub-components at the copyin/copyout points.
Reviewed by: kib
Sponsored by: Juniper Networks, Inc.
Differential Revision: https://reviews.freebsd.org/D35225
(cherry picked from commit 47a57144af25a7bd768b29272d50a36fdf2874ba)
---
sys/compat/freebsd32/freebsd32_misc.c | 70 +++++++++++++++++++++++++++++++++--
sys/kern/kern_cpuset.c | 33 +++++++++++------
sys/sys/cpuset.h | 9 +++++
sys/sys/syscallsubr.h | 10 +++--
4 files changed, 102 insertions(+), 20 deletions(-)
diff --git a/sys/compat/freebsd32/freebsd32_misc.c b/sys/compat/freebsd32/freebsd32_misc.c
index 177a7bf05ee4..af5d91d59fbc 100644
--- a/sys/compat/freebsd32/freebsd32_misc.c
+++ b/sys/compat/freebsd32/freebsd32_misc.c
@@ -3249,13 +3249,72 @@ freebsd32_cpuset_getid(struct thread *td,
PAIR32TO64(id_t, uap->id), uap->setid));
}
+static int
+copyin32_set(const void *u, void *k, size_t size)
+{
+#if __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__
+ int rv;
+ struct bitset *kb = k;
+ int *p;
+
+ rv = copyin(u, k, size);
+ if (rv != 0)
+ return (rv);
+
+ p = (int *)kb->__bits;
+ /* Loop through swapping words.
+ * `size' is in bytes, we need bits. */
+ for (int i = 0; i < __bitset_words(size * 8); i++) {
+ int tmp = p[0];
+ p[0] = p[1];
+ p[1] = tmp;
+ p += 2;
+ }
+ return (0);
+#else
+ return (copyin(u, k, size));
+#endif
+}
+
+static int
+copyout32_set(const void *k, void *u, size_t size)
+{
+#if __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__
+ const struct bitset *kb = k;
+ struct bitset *ub = u;
+ const int *kp = (const int *)kb->__bits;
+ int *up = (int *)ub->__bits;
+ int rv;
+
+ for (int i = 0; i < __bitset_words(CPU_SETSIZE); i++) {
+ /* `size' is in bytes, we need bits. */
+ for (int i = 0; i < __bitset_words(size * 8); i++) {
+ rv = suword32(up, kp[1]);
+ if (rv == 0)
+ rv = suword32(up + 1, kp[0]);
+ if (rv != 0)
+ return (EFAULT);
+ }
+ }
+ return (0);
+#else
+ return (copyout(k, u, size));
+#endif
+}
+
+static const struct cpuset_copy_cb cpuset_copy32_cb = {
+ .copyin = copyin32_set,
+ .copyout = copyout32_set
+};
+
int
freebsd32_cpuset_getaffinity(struct thread *td,
struct freebsd32_cpuset_getaffinity_args *uap)
{
return (kern_cpuset_getaffinity(td, uap->level, uap->which,
- PAIR32TO64(id_t,uap->id), uap->cpusetsize, uap->mask));
+ PAIR32TO64(id_t,uap->id), uap->cpusetsize, uap->mask,
+ &cpuset_copy32_cb));
}
int
@@ -3264,7 +3323,8 @@ freebsd32_cpuset_setaffinity(struct thread *td,
{
return (kern_cpuset_setaffinity(td, uap->level, uap->which,
- PAIR32TO64(id_t,uap->id), uap->cpusetsize, uap->mask));
+ PAIR32TO64(id_t,uap->id), uap->cpusetsize, uap->mask,
+ &cpuset_copy32_cb));
}
int
@@ -3273,7 +3333,8 @@ freebsd32_cpuset_getdomain(struct thread *td,
{
return (kern_cpuset_getdomain(td, uap->level, uap->which,
- PAIR32TO64(id_t,uap->id), uap->domainsetsize, uap->mask, uap->policy));
+ PAIR32TO64(id_t,uap->id), uap->domainsetsize, uap->mask, uap->policy,
+ &cpuset_copy32_cb));
}
int
@@ -3282,7 +3343,8 @@ freebsd32_cpuset_setdomain(struct thread *td,
{
return (kern_cpuset_setdomain(td, uap->level, uap->which,
- PAIR32TO64(id_t,uap->id), uap->domainsetsize, uap->mask, uap->policy));
+ PAIR32TO64(id_t,uap->id), uap->domainsetsize, uap->mask, uap->policy,
+ &cpuset_copy32_cb));
}
int
diff --git a/sys/kern/kern_cpuset.c b/sys/kern/kern_cpuset.c
index 962e7abb44b7..9c81dd7a7874 100644
--- a/sys/kern/kern_cpuset.c
+++ b/sys/kern/kern_cpuset.c
@@ -51,6 +51,7 @@ __FBSDID("$FreeBSD$");
#include <sys/sched.h>
#include <sys/smp.h>
#include <sys/syscallsubr.h>
+#include <sys/sysent.h>
#include <sys/capsicum.h>
#include <sys/cpuset.h>
#include <sys/domainset.h>
@@ -1740,6 +1741,11 @@ cpuset_check_capabilities(struct thread *td, cpulevel_t level, cpuwhich_t which,
return (0);
}
+static const struct cpuset_copy_cb copy_set = {
+ .copyin = copyin,
+ .copyout = copyout
+};
+
#ifndef _SYS_SYSPROTO_H_
struct cpuset_args {
cpusetid_t *setid;
@@ -1881,12 +1887,12 @@ sys_cpuset_getaffinity(struct thread *td, struct cpuset_getaffinity_args *uap)
{
return (kern_cpuset_getaffinity(td, uap->level, uap->which,
- uap->id, uap->cpusetsize, uap->mask));
+ uap->id, uap->cpusetsize, uap->mask, ©_set));
}
int
kern_cpuset_getaffinity(struct thread *td, cpulevel_t level, cpuwhich_t which,
- id_t id, size_t cpusetsize, cpuset_t *maskp)
+ id_t id, size_t cpusetsize, cpuset_t *maskp, const struct cpuset_copy_cb *cb)
{
struct thread *ttd;
struct cpuset *nset;
@@ -1973,7 +1979,7 @@ kern_cpuset_getaffinity(struct thread *td, cpulevel_t level, cpuwhich_t which,
if (p)
PROC_UNLOCK(p);
if (error == 0)
- error = copyout(mask, maskp, size);
+ error = cb->copyout(mask, maskp, size);
out:
free(mask, M_TEMP);
return (error);
@@ -1993,12 +1999,13 @@ sys_cpuset_setaffinity(struct thread *td, struct cpuset_setaffinity_args *uap)
{
return (kern_cpuset_setaffinity(td, uap->level, uap->which,
- uap->id, uap->cpusetsize, uap->mask));
+ uap->id, uap->cpusetsize, uap->mask, ©_set));
}
int
kern_cpuset_setaffinity(struct thread *td, cpulevel_t level, cpuwhich_t which,
- id_t id, size_t cpusetsize, const cpuset_t *maskp)
+ id_t id, size_t cpusetsize, const cpuset_t *maskp,
+ const struct cpuset_copy_cb *cb)
{
struct cpuset *nset;
struct cpuset *set;
@@ -2013,7 +2020,7 @@ kern_cpuset_setaffinity(struct thread *td, cpulevel_t level, cpuwhich_t which,
if (error != 0)
return (error);
mask = malloc(cpusetsize, M_TEMP, M_WAITOK | M_ZERO);
- error = copyin(maskp, mask, cpusetsize);
+ error = cb->cpuset_copyin(maskp, mask, cpusetsize);
if (error)
goto out;
/*
@@ -2118,12 +2125,13 @@ sys_cpuset_getdomain(struct thread *td, struct cpuset_getdomain_args *uap)
{
return (kern_cpuset_getdomain(td, uap->level, uap->which,
- uap->id, uap->domainsetsize, uap->mask, uap->policy));
+ uap->id, uap->domainsetsize, uap->mask, uap->policy, ©_set));
}
int
kern_cpuset_getdomain(struct thread *td, cpulevel_t level, cpuwhich_t which,
- id_t id, size_t domainsetsize, domainset_t *maskp, int *policyp)
+ id_t id, size_t domainsetsize, domainset_t *maskp, int *policyp,
+ const struct cpuset_copy_cb *cb)
{
struct domainset outset;
struct thread *ttd;
@@ -2221,7 +2229,7 @@ kern_cpuset_getdomain(struct thread *td, cpulevel_t level, cpuwhich_t which,
}
DOMAINSET_COPY(&outset.ds_mask, mask);
if (error == 0)
- error = copyout(mask, maskp, domainsetsize);
+ error = cb->copyout(mask, maskp, domainsetsize);
if (error == 0)
if (suword32(policyp, outset.ds_policy) != 0)
error = EFAULT;
@@ -2245,12 +2253,13 @@ sys_cpuset_setdomain(struct thread *td, struct cpuset_setdomain_args *uap)
{
return (kern_cpuset_setdomain(td, uap->level, uap->which,
- uap->id, uap->domainsetsize, uap->mask, uap->policy));
+ uap->id, uap->domainsetsize, uap->mask, uap->policy, ©_set));
}
int
kern_cpuset_setdomain(struct thread *td, cpulevel_t level, cpuwhich_t which,
- id_t id, size_t domainsetsize, const domainset_t *maskp, int policy)
+ id_t id, size_t domainsetsize, const domainset_t *maskp, int policy,
+ const struct cpuset_copy_cb *cb)
{
struct cpuset *nset;
struct cpuset *set;
@@ -2271,7 +2280,7 @@ kern_cpuset_setdomain(struct thread *td, cpulevel_t level, cpuwhich_t which,
return (error);
memset(&domain, 0, sizeof(domain));
mask = malloc(domainsetsize, M_TEMP, M_WAITOK | M_ZERO);
- error = copyin(maskp, mask, domainsetsize);
+ error = cb->copyin(maskp, mask, domainsetsize);
if (error)
goto out;
/*
diff --git a/sys/sys/cpuset.h b/sys/sys/cpuset.h
index 0ce470d5f569..4f55cdc27103 100644
--- a/sys/sys/cpuset.h
+++ b/sys/sys/cpuset.h
@@ -154,6 +154,15 @@ struct prison;
struct proc;
struct thread;
+/*
+ * Callbacks for copying in/out a cpuset or domainset. Used for alternate
+ * ABIs, like compat32.
+ */
+struct cpuset_copy_cb {
+ int (*copyin)(const void *, void *, size_t);
+ int (*copyout)(const void *, void *, size_t);
+};
+
struct cpuset *cpuset_thread0(void);
struct cpuset *cpuset_ref(struct cpuset *);
void cpuset_rel(struct cpuset *);
diff --git a/sys/sys/syscallsubr.h b/sys/sys/syscallsubr.h
index 2f1c35dba48b..5653c36f1db4 100644
--- a/sys/sys/syscallsubr.h
+++ b/sys/sys/syscallsubr.h
@@ -39,6 +39,7 @@
#include <sys/_uio.h>
struct __wrusage;
+struct cpuset_copy_cb;
struct file;
struct filecaps;
enum idtype;
@@ -115,16 +116,17 @@ int kern_connectat(struct thread *td, int dirfd, int fd,
int kern_copy_file_range(struct thread *td, int infd, off_t *inoffp,
int outfd, off_t *outoffp, size_t len, unsigned int flags);
int kern_cpuset_getaffinity(struct thread *td, cpulevel_t level,
- cpuwhich_t which, id_t id, size_t cpusetsize, cpuset_t *maskp);
+ cpuwhich_t which, id_t id, size_t cpusetsize, cpuset_t *maskp,
+ const struct cpuset_copy_cb *cb);
int kern_cpuset_setaffinity(struct thread *td, cpulevel_t level,
cpuwhich_t which, id_t id, size_t cpusetsize,
- const cpuset_t *maskp);
+ const cpuset_t *maskp, const struct cpuset_copy_cb *cb);
int kern_cpuset_getdomain(struct thread *td, cpulevel_t level,
cpuwhich_t which, id_t id, size_t domainsetsize,
- domainset_t *maskp, int *policyp);
+ domainset_t *maskp, int *policyp, const struct cpuset_copy_cb *cb);
int kern_cpuset_setdomain(struct thread *td, cpulevel_t level,
cpuwhich_t which, id_t id, size_t domainsetsize,
- const domainset_t *maskp, int policy);
+ const domainset_t *maskp, int policy, const struct cpuset_copy_cb *cb);
int kern_cpuset_getid(struct thread *td, cpulevel_t level,
cpuwhich_t which, id_t id, cpusetid_t *setid);
int kern_cpuset_setid(struct thread *td, cpuwhich_t which,