cregit-Linux how code gets into the kernel

Release 4.17 net/compat.c

Directory: net
/*
 * 32bit Socket syscall emulation. Based on arch/sparc64/kernel/sys_sparc32.c.
 *
 * Copyright (C) 2000           VA Linux Co
 * Copyright (C) 2000           Don Dugger <n0ano@valinux.com>
 * Copyright (C) 1999           Arun Sharma <arun.sharma@intel.com>
 * Copyright (C) 1997,1998      Jakub Jelinek (jj@sunsite.mff.cuni.cz)
 * Copyright (C) 1997           David S. Miller (davem@caip.rutgers.edu)
 * Copyright (C) 2000           Hewlett-Packard Co.
 * Copyright (C) 2000           David Mosberger-Tang <davidm@hpl.hp.com>
 * Copyright (C) 2000,2001      Andi Kleen, SuSE Labs
 */

#include <linux/kernel.h>
#include <linux/gfp.h>
#include <linux/fs.h>
#include <linux/types.h>
#include <linux/file.h>
#include <linux/icmpv6.h>
#include <linux/socket.h>
#include <linux/syscalls.h>
#include <linux/filter.h>
#include <linux/compat.h>
#include <linux/security.h>
#include <linux/audit.h>
#include <linux/export.h>

#include <net/scm.h>
#include <net/sock.h>
#include <net/ip.h>
#include <net/ipv6.h>
#include <linux/uaccess.h>
#include <net/compat.h>


int get_compat_msghdr(struct msghdr *kmsg, struct compat_msghdr __user *umsg, struct sockaddr __user **save_addr, struct iovec **iov) { struct compat_msghdr msg; ssize_t err; if (copy_from_user(&msg, umsg, sizeof(*umsg))) return -EFAULT; kmsg->msg_flags = msg.msg_flags; kmsg->msg_namelen = msg.msg_namelen; if (!msg.msg_name) kmsg->msg_namelen = 0; if (kmsg->msg_namelen < 0) return -EINVAL; if (kmsg->msg_namelen > sizeof(struct sockaddr_storage)) kmsg->msg_namelen = sizeof(struct sockaddr_storage); kmsg->msg_control = compat_ptr(msg.msg_control); kmsg->msg_controllen = msg.msg_controllen; if (save_addr) *save_addr = compat_ptr(msg.msg_name); if (msg.msg_name && kmsg->msg_namelen) { if (!save_addr) { err = move_addr_to_kernel(compat_ptr(msg.msg_name), kmsg->msg_namelen, kmsg->msg_name); if (err < 0) return err; } } else { kmsg->msg_name = NULL; kmsg->msg_namelen = 0; } if (msg.msg_iovlen > UIO_MAXIOV) return -EMSGSIZE; kmsg->msg_iocb = NULL; return compat_import_iovec(save_addr ? READ : WRITE, compat_ptr(msg.msg_iov), msg.msg_iovlen, UIO_FASTIOV, iov, &kmsg->msg_iter); }

Contributors

PersonTokensPropCommitsCommitProp
Al Viro12447.15%642.86%
Andi Kleen5019.01%17.14%
Stephen Rothwell2911.03%17.14%
Catalin Marinas228.37%17.14%
Dan Carpenter228.37%214.29%
Andrey Ryabinin93.42%17.14%
Tadeusz Struk62.28%17.14%
Benjamin LaHaise10.38%17.14%
Total263100.00%14100.00%

/* Bleech... */ #define CMSG_COMPAT_ALIGN(len) ALIGN((len), sizeof(s32)) #define CMSG_COMPAT_DATA(cmsg) \ ((void __user *)((char __user *)(cmsg) + sizeof(struct compat_cmsghdr))) #define CMSG_COMPAT_SPACE(len) \ (sizeof(struct compat_cmsghdr) + CMSG_COMPAT_ALIGN(len)) #define CMSG_COMPAT_LEN(len) \ (sizeof(struct compat_cmsghdr) + (len)) #define CMSG_COMPAT_FIRSTHDR(msg) \ (((msg)->msg_controllen) >= sizeof(struct compat_cmsghdr) ? \ (struct compat_cmsghdr __user *)((msg)->msg_control) : \ (struct compat_cmsghdr __user *)NULL) #define CMSG_COMPAT_OK(ucmlen, ucmsg, mhdr) \ ((ucmlen) >= sizeof(struct compat_cmsghdr) && \ (ucmlen) <= (unsigned long) \ ((mhdr)->msg_controllen - \ ((char *)(ucmsg) - (char *)(mhdr)->msg_control)))
static inline struct compat_cmsghdr __user *cmsg_compat_nxthdr(struct msghdr *msg, struct compat_cmsghdr __user *cmsg, int cmsg_len) { char __user *ptr = (char __user *)cmsg + CMSG_COMPAT_ALIGN(cmsg_len); if ((unsigned long)(ptr + 1 - (char __user *)msg->msg_control) > msg->msg_controllen) return NULL; return (struct compat_cmsghdr __user *)ptr; }

Contributors

PersonTokensPropCommitsCommitProp
Stephen Rothwell5367.95%133.33%
Al Viro1417.95%133.33%
Andi Kleen1114.10%133.33%
Total78100.00%3100.00%

/* There is a lot of hair here because the alignment rules (and * thus placement) of cmsg headers and length are different for * 32-bit apps. -DaveM */
int cmsghdr_from_user_compat_to_kern(struct msghdr *kmsg, struct sock *sk, unsigned char *stackbuf, int stackbuf_size) { struct compat_cmsghdr __user *ucmsg; struct cmsghdr *kcmsg, *kcmsg_base; compat_size_t ucmlen; __kernel_size_t kcmlen, tmp; int err = -EFAULT; BUILD_BUG_ON(sizeof(struct compat_cmsghdr) != CMSG_COMPAT_ALIGN(sizeof(struct compat_cmsghdr))); kcmlen = 0; kcmsg_base = kcmsg = (struct cmsghdr *)stackbuf; ucmsg = CMSG_COMPAT_FIRSTHDR(kmsg); while (ucmsg != NULL) { if (get_user(ucmlen, &ucmsg->cmsg_len)) return -EFAULT; /* Catch bogons. */ if (!CMSG_COMPAT_OK(ucmlen, ucmsg, kmsg)) return -EINVAL; tmp = ((ucmlen - sizeof(*ucmsg)) + sizeof(struct cmsghdr)); tmp = CMSG_ALIGN(tmp); kcmlen += tmp; ucmsg = cmsg_compat_nxthdr(kmsg, ucmsg, ucmlen); } if (kcmlen == 0) return -EINVAL; /* The kcmlen holds the 64-bit version of the control length. * It may not be modified as we do not stick it into the kmsg * until we have successfully copied over all of the data * from the user. */ if (kcmlen > stackbuf_size) kcmsg_base = kcmsg = sock_kmalloc(sk, kcmlen, GFP_KERNEL); if (kcmsg == NULL) return -ENOBUFS; /* Now copy them over neatly. */ memset(kcmsg, 0, kcmlen); ucmsg = CMSG_COMPAT_FIRSTHDR(kmsg); while (ucmsg != NULL) { if (__get_user(ucmlen, &ucmsg->cmsg_len)) goto Efault; if (!CMSG_COMPAT_OK(ucmlen, ucmsg, kmsg)) goto Einval; tmp = ((ucmlen - sizeof(*ucmsg)) + sizeof(struct cmsghdr)); if ((char *)kcmsg_base + kcmlen - (char *)kcmsg < CMSG_ALIGN(tmp)) goto Einval; kcmsg->cmsg_len = tmp; tmp = CMSG_ALIGN(tmp); if (__get_user(kcmsg->cmsg_level, &ucmsg->cmsg_level) || __get_user(kcmsg->cmsg_type, &ucmsg->cmsg_type) || copy_from_user(CMSG_DATA(kcmsg), CMSG_COMPAT_DATA(ucmsg), (ucmlen - sizeof(*ucmsg)))) goto Efault; /* Advance. */ kcmsg = (struct cmsghdr *)((char *)kcmsg + tmp); ucmsg = cmsg_compat_nxthdr(kmsg, ucmsg, ucmlen); } /* * check the length of messages copied in is the same as the * what we get from the first loop */ if ((char *)kcmsg - (char *)kcmsg_base != kcmlen) goto Einval; /* Ok, looks like we made it. Hook it up and return success. */ kmsg->msg_control = kcmsg_base; kmsg->msg_controllen = kcmlen; return 0; Einval: err = -EINVAL; Efault: if (kcmsg_base != (struct cmsghdr *)stackbuf) sock_kfree_s(sk, kcmsg_base, kcmlen); return err; }

Contributors

PersonTokensPropCommitsCommitProp
Andi Kleen29061.05%112.50%
Al Viro9319.58%225.00%
Stephen Rothwell479.89%112.50%
David S. Miller224.63%225.00%
Meng Xu204.21%112.50%
Benjamin LaHaise30.63%112.50%
Total475100.00%8100.00%


int put_cmsg_compat(struct msghdr *kmsg, int level, int type, int len, void *data) { struct compat_cmsghdr __user *cm = (struct compat_cmsghdr __user *) kmsg->msg_control; struct compat_cmsghdr cmhdr; struct compat_timeval ctv; struct compat_timespec cts[3]; int cmlen; if (cm == NULL || kmsg->msg_controllen < sizeof(*cm)) { kmsg->msg_flags |= MSG_CTRUNC; return 0; /* XXX: return error? check spec. */ } if (!COMPAT_USE_64BIT_TIME) { if (level == SOL_SOCKET && type == SCM_TIMESTAMP) { struct timeval *tv = (struct timeval *)data; ctv.tv_sec = tv->tv_sec; ctv.tv_usec = tv->tv_usec; data = &ctv; len = sizeof(ctv); } if (level == SOL_SOCKET && (type == SCM_TIMESTAMPNS || type == SCM_TIMESTAMPING)) { int count = type == SCM_TIMESTAMPNS ? 1 : 3; int i; struct timespec *ts = (struct timespec *)data; for (i = 0; i < count; i++) { cts[i].tv_sec = ts[i].tv_sec; cts[i].tv_nsec = ts[i].tv_nsec; } data = &cts; len = sizeof(cts[0]) * count; } } cmlen = CMSG_COMPAT_LEN(len); if (kmsg->msg_controllen < cmlen) { kmsg->msg_flags |= MSG_CTRUNC; cmlen = kmsg->msg_controllen; } cmhdr.cmsg_level = level; cmhdr.cmsg_type = type; cmhdr.cmsg_len = cmlen; if (copy_to_user(cm, &cmhdr, sizeof cmhdr)) return -EFAULT; if (copy_to_user(CMSG_COMPAT_DATA(cm), data, cmlen - sizeof(struct compat_cmsghdr))) return -EFAULT; cmlen = CMSG_COMPAT_SPACE(len); if (kmsg->msg_controllen < cmlen) cmlen = kmsg->msg_controllen; kmsg->msg_control += cmlen; kmsg->msg_controllen -= cmlen; return 0; }

Contributors

PersonTokensPropCommitsCommitProp
Andi Kleen21056.45%220.00%
Patrick Ohly5615.05%220.00%
Eric Dumazet4913.17%110.00%
Benjamin LaHaise236.18%110.00%
Wei Yongjun143.76%110.00%
Jesper Juhl112.96%110.00%
H. J. Lu71.88%110.00%
Al Viro20.54%110.00%
Total372100.00%10100.00%


void scm_detach_fds_compat(struct msghdr *kmsg, struct scm_cookie *scm) { struct compat_cmsghdr __user *cm = (struct compat_cmsghdr __user *) kmsg->msg_control; int fdmax = (kmsg->msg_controllen - sizeof(struct compat_cmsghdr)) / sizeof(int); int fdnum = scm->fp->count; struct file **fp = scm->fp->fp; int __user *cmfptr; int err = 0, i; if (fdnum < fdmax) fdmax = fdnum; for (i = 0, cmfptr = (int __user *) CMSG_COMPAT_DATA(cm); i < fdmax; i++, cmfptr++) { int new_fd; err = security_file_receive(fp[i]); if (err) break; err = get_unused_fd_flags(MSG_CMSG_CLOEXEC & kmsg->msg_flags ? O_CLOEXEC : 0); if (err < 0) break; new_fd = err; err = put_user(new_fd, cmfptr); if (err) { put_unused_fd(new_fd); break; } /* Bump the usage count and install the file. */ fd_install(new_fd, get_file(fp[i])); } if (i > 0) { int cmlen = CMSG_COMPAT_LEN(i * sizeof(int)); err = put_user(SOL_SOCKET, &cm->cmsg_level); if (!err) err = put_user(SCM_RIGHTS, &cm->cmsg_type); if (!err) err = put_user(cmlen, &cm->cmsg_len); if (!err) { cmlen = CMSG_COMPAT_SPACE(i * sizeof(int)); kmsg->msg_control += cmlen; kmsg->msg_controllen -= cmlen; } } if (i < fdnum) kmsg->msg_flags |= MSG_CTRUNC; /* * All of the files that fit in the message have had their * usage counts incremented, so we just free the list. */ __scm_destroy(scm); }

Contributors

PersonTokensPropCommitsCommitProp
Andi Kleen27887.15%116.67%
Mitchell Blank Jr.154.70%116.67%
Ulrich Drepper123.76%116.67%
Al Viro72.19%233.33%
Benjamin LaHaise72.19%116.67%
Total319100.00%6100.00%

/* allocate a 64-bit sock_fprog on the user stack for duration of syscall. */
struct sock_fprog __user *get_compat_bpf_fprog(char __user *optval) { struct compat_sock_fprog __user *fprog32 = (struct compat_sock_fprog __user *)optval; struct sock_fprog __user *kfprog = compat_alloc_user_space(sizeof(struct sock_fprog)); struct compat_sock_fprog f32; struct sock_fprog f; if (copy_from_user(&f32, fprog32, sizeof(*fprog32))) return NULL; memset(&f, 0, sizeof(f)); f.len = f32.len; f.filter = compat_ptr(f32.filter); if (copy_to_user(kfprog, &f, sizeof(struct sock_fprog))) return NULL; return kfprog; }

Contributors

PersonTokensPropCommitsCommitProp
Al Viro4637.40%222.22%
Andi Kleen2923.58%222.22%
David S. Miller2117.07%111.11%
Stephen Rothwell1411.38%111.11%
Willem de Bruijn108.13%111.11%
Dmitry Mishin21.63%111.11%
Randolph Chung10.81%111.11%
Total123100.00%9100.00%

EXPORT_SYMBOL_GPL(get_compat_bpf_fprog);
static int do_set_attach_filter(struct socket *sock, int level, int optname, char __user *optval, unsigned int optlen) { struct sock_fprog __user *kfprog; kfprog = get_compat_bpf_fprog(optval); if (!kfprog) return -EFAULT; return sock_setsockopt(sock, level, optname, (char __user *)kfprog, sizeof(struct sock_fprog)); }

Contributors

PersonTokensPropCommitsCommitProp
Willem de Bruijn4461.97%120.00%
Andi Kleen2129.58%120.00%
David S. Miller34.23%120.00%
Dmitry Mishin22.82%120.00%
Al Viro11.41%120.00%
Total71100.00%5100.00%


static int do_set_sock_timeout(struct socket *sock, int level, int optname, char __user *optval, unsigned int optlen) { struct compat_timeval __user *up = (struct compat_timeval __user *)optval; struct timeval ktime; mm_segment_t old_fs; int err; if (optlen < sizeof(*up)) return -EINVAL; if (!access_ok(VERIFY_READ, up, sizeof(*up)) || __get_user(ktime.tv_sec, &up->tv_sec) || __get_user(ktime.tv_usec, &up->tv_usec)) return -EFAULT; old_fs = get_fs(); set_fs(KERNEL_DS); err = sock_setsockopt(sock, level, optname, (char *)&ktime, sizeof(ktime)); set_fs(old_fs); return err; }

Contributors

PersonTokensPropCommitsCommitProp
Andi Kleen12483.22%120.00%
Stephen Rothwell1510.07%120.00%
Dmitry Mishin64.03%120.00%
Al Viro32.01%120.00%
David S. Miller10.67%120.00%
Total149100.00%5100.00%


static int compat_sock_setsockopt(struct socket *sock, int level, int optname, char __user *optval, unsigned int optlen) { if (optname == SO_ATTACH_FILTER || optname == SO_ATTACH_REUSEPORT_CBPF) return do_set_attach_filter(sock, level, optname, optval, optlen); if (!COMPAT_USE_64BIT_TIME && (optname == SO_RCVTIMEO || optname == SO_SNDTIMEO)) return do_set_sock_timeout(sock, level, optname, optval, optlen); return sock_setsockopt(sock, level, optname, optval, optlen); }

Contributors

PersonTokensPropCommitsCommitProp
Dmitry Mishin8389.25%125.00%
Lance Richardson55.38%125.00%
Helge Deller44.30%125.00%
David S. Miller11.08%125.00%
Total93100.00%4100.00%


static int __compat_sys_setsockopt(int fd, int level, int optname, char __user *optval, unsigned int optlen) { int err; struct socket *sock = sockfd_lookup(fd, &err); if (sock) { err = security_socket_setsockopt(sock, level, optname); if (err) { sockfd_put(sock); return err; } if (level == SOL_SOCKET) err = compat_sock_setsockopt(sock, level, optname, optval, optlen); else if (sock->ops->compat_setsockopt) err = sock->ops->compat_setsockopt(sock, level, optname, optval, optlen); else err = sock->ops->setsockopt(sock, level, optname, optval, optlen); sockfd_put(sock); } return err; }

Contributors

PersonTokensPropCommitsCommitProp
Dmitry Mishin8356.08%116.67%
Andi Kleen3523.65%233.33%
Dominik Brodowski2214.86%116.67%
Eric Dumazet53.38%116.67%
David Woodhouse32.03%116.67%
Total148100.00%6100.00%

COMPAT_SYSCALL_DEFINE5(setsockopt, int, fd, int, level, int, optname, char __user *, optval, unsigned int, optlen) { return __compat_sys_setsockopt(fd, level, optname, optval, optlen); }
static int do_get_sock_timeout(struct socket *sock, int level, int optname, char __user *optval, int __user *optlen) { struct compat_timeval __user *up; struct timeval ktime; mm_segment_t old_fs; int len, err; up = (struct compat_timeval __user *) optval; if (get_user(len, optlen)) return -EFAULT; if (len < sizeof(*up)) return -EINVAL; len = sizeof(ktime); old_fs = get_fs(); set_fs(KERNEL_DS); err = sock_getsockopt(sock, level, optname, (char *) &ktime, &len); set_fs(old_fs); if (!err) { if (put_user(sizeof(*up), optlen) || !access_ok(VERIFY_WRITE, up, sizeof(*up)) || __put_user(ktime.tv_sec, &up->tv_sec) || __put_user(ktime.tv_usec, &up->tv_usec)) err = -EFAULT; } return err; }

Contributors

PersonTokensPropCommitsCommitProp
Andi Kleen15782.20%125.00%
Stephen Rothwell157.85%125.00%
Al Viro136.81%125.00%
Dmitry Mishin63.14%125.00%
Total191100.00%4100.00%


static int compat_sock_getsockopt(struct socket *sock, int level, int optname, char __user *optval, int __user *optlen) { if (!COMPAT_USE_64BIT_TIME && (optname == SO_RCVTIMEO || optname == SO_SNDTIMEO)) return do_get_sock_timeout(sock, level, optname, optval, optlen); return sock_getsockopt(sock, level, optname, optval, optlen); }

Contributors

PersonTokensPropCommitsCommitProp
Andi Kleen4260.00%125.00%
Dmitry Mishin2130.00%125.00%
Lance Richardson57.14%125.00%
Al Viro22.86%125.00%
Total70100.00%4100.00%


int compat_sock_get_timestamp(struct sock *sk, struct timeval __user *userstamp) { struct compat_timeval __user *ctv; int err; struct timeval tv; if (COMPAT_USE_64BIT_TIME) return sock_get_timestamp(sk, userstamp); ctv = (struct compat_timeval __user *) userstamp; err = -ENOENT; if (!sock_flag(sk, SOCK_TIMESTAMP)) sock_enable_timestamp(sk, SOCK_TIMESTAMP); tv = ktime_to_timeval(sk->sk_stamp); if (tv.tv_sec == -1) return err; if (tv.tv_sec == 0) { sk->sk_stamp = ktime_get_real(); tv = ktime_to_timeval(sk->sk_stamp); } err = 0; if (put_user(tv.tv_sec, &ctv->tv_sec) || put_user(tv.tv_usec, &ctv->tv_usec)) err = -EFAULT; return err; }

Contributors

PersonTokensPropCommitsCommitProp
Shaun Pereira10365.19%125.00%
Eric Dumazet2817.72%125.00%
H. J. Lu2515.82%125.00%
Patrick Ohly21.27%125.00%
Total158100.00%4100.00%

EXPORT_SYMBOL(compat_sock_get_timestamp);
int compat_sock_get_timestampns(struct sock *sk, struct timespec __user *userstamp) { struct compat_timespec __user *ctv; int err; struct timespec ts; if (COMPAT_USE_64BIT_TIME) return sock_get_timestampns (sk, userstamp); ctv = (struct compat_timespec __user *) userstamp; err = -ENOENT; if (!sock_flag(sk, SOCK_TIMESTAMP)) sock_enable_timestamp(sk, SOCK_TIMESTAMP); ts = ktime_to_timespec(sk->sk_stamp); if (ts.tv_sec == -1) return err; if (ts.tv_sec == 0) { sk->sk_stamp = ktime_get_real(); ts = ktime_to_timespec(sk->sk_stamp); } err = 0; if (put_user(ts.tv_sec, &ctv->tv_sec) || put_user(ts.tv_nsec, &ctv->tv_nsec)) err = -EFAULT; return err; }

Contributors

PersonTokensPropCommitsCommitProp
Eric Dumazet13182.91%133.33%
H. J. Lu2515.82%133.33%
Patrick Ohly21.27%133.33%
Total158100.00%3100.00%

EXPORT_SYMBOL(compat_sock_get_timestampns);