The branch stable/13 has been updated by jhibbits:

URL: 
https://cgit.FreeBSD.org/src/commit/?id=971cb62e0b23f0a962f3348d82e70b331fe41268

commit 971cb62e0b23f0a962f3348d82e70b331fe41268
Author:     Justin Hibbits <jhibb...@freebsd.org>
AuthorDate: 2022-05-12 20:38:22 +0000
Commit:     Justin Hibbits <jhibb...@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, &copy_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, &copy_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, &copy_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, &copy_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,

Reply via email to