int32_t NaClSysFtruncate(struct NaClAppThread *natp,
int d,
uint32_t lengthp) {
struct NaClApp *nap = natp->nap;
struct NaClDesc *ndp;
nacl_abi_off_t length;
int32_t retval = -NACL_ABI_EINVAL;
NaClLog(3,
("Entered NaClSysFtruncate(0x%08"NACL_PRIxPTR", %d,"
" 0x%"NACL_PRIx32")\n"),
(uintptr_t) natp, d, lengthp);
ndp = NaClAppGetDesc(nap, d);
if (NULL == ndp) {
retval = -NACL_ABI_EBADF;
goto cleanup;
}
if (!NaClCopyInFromUser(nap, &length, lengthp, sizeof length)) {
retval = -NACL_ABI_EFAULT;
goto cleanup_unref;
}
NaClLog(4, "length 0x%08"NACL_PRIx64"\n", (uint64_t) length);
retval = (*((struct NaClDescVtbl const *) ndp->base.vtbl)->
Ftruncate)(ndp, length);
cleanup_unref:
NaClDescUnref(ndp);
cleanup:
return retval;
}
/*
* This implements 64-bit offsets, so we use |offp| as an in/out
* address so we can have a 64 bit return value.
*/
int32_t NaClSysLseek(struct NaClAppThread *natp,
int d,
uint32_t offp,
int whence) {
struct NaClApp *nap = natp->nap;
nacl_abi_off_t offset;
nacl_off64_t retval64;
int32_t retval = -NACL_ABI_EINVAL;
struct NaClDesc *ndp;
NaClLog(3,
("Entered NaClSysLseek(0x%08"NACL_PRIxPTR", %d,"
" 0x%08"NACL_PRIx32", %d)\n"),
(uintptr_t) natp, d, offp, whence);
ndp = NaClAppGetDesc(nap, d);
if (NULL == ndp) {
retval = -NACL_ABI_EBADF;
goto cleanup;
}
if (!NaClCopyInFromUser(nap, &offset, offp, sizeof offset)) {
retval = -NACL_ABI_EFAULT;
goto cleanup_unref;
}
NaClLog(4, "offset 0x%08"NACL_PRIx64"\n", (uint64_t) offset);
retval64 = (*((struct NaClDescVtbl const *) ndp->base.vtbl)->
Seek)(ndp, (nacl_off64_t) offset, whence);
if (NaClOff64IsNegErrno(&retval64)) {
retval = (int32_t) retval64;
} else {
if (NaClCopyOutToUser(nap, offp, &retval64, sizeof retval64)) {
retval = 0;
} else {
NaClLog(LOG_FATAL,
"NaClSysLseek: in/out ptr became invalid at copyout?\n");
}
}
cleanup_unref:
NaClDescUnref(ndp);
cleanup:
return retval;
}
int32_t NaClSysTruncate(struct NaClAppThread *natp,
uint32_t pathname,
uint32_t length_addr) {
struct NaClApp *nap = natp->nap;
char path[NACL_CONFIG_PATH_MAX];
int32_t retval = -NACL_ABI_EINVAL;
nacl_abi_off_t length;
if (!NaClAclBypassChecks)
return -NACL_ABI_EACCES;
retval = CopyPathFromUser(nap, path, sizeof path, pathname);
if (0 != retval)
return retval;
if (!NaClCopyInFromUser(nap, &length, length_addr, sizeof length))
return -NACL_ABI_EFAULT;
retval = NaClHostDescTruncate(path, length);
NaClLog(3, "NaClHostDescTruncate '%s' %"NACL_PRId64" -> %d\n",
path, length, retval);
return retval;
}
int32_t NaClSysImcRecvmsg(struct NaClAppThread *natp,
int d,
uint32_t nanimhp,
int flags) {
struct NaClApp *nap = natp->nap;
int32_t retval = -NACL_ABI_EINVAL;
ssize_t ssize_retval;
uintptr_t sysaddr;
size_t i;
struct NaClDesc *ndp;
struct NaClAbiNaClImcMsgHdr kern_nanimh;
struct NaClAbiNaClImcMsgIoVec kern_naiov[NACL_ABI_IMC_IOVEC_MAX];
struct NaClImcMsgIoVec kern_iov[NACL_ABI_IMC_IOVEC_MAX];
int32_t usr_desc[NACL_ABI_IMC_USER_DESC_MAX];
struct NaClImcTypedMsgHdr recv_hdr;
struct NaClDesc *new_desc[NACL_ABI_IMC_DESC_MAX];
nacl_abi_size_t num_user_desc;
struct NaClDesc *invalid_desc = NULL;
NaClLog(3,
("Entered NaClSysImcRecvMsg(0x%08"NACL_PRIxPTR", %d,"
" 0x%08"NACL_PRIx32")\n"),
(uintptr_t) natp, d, nanimhp);
/*
* First, we validate user-supplied message headers before
* allocating a receive buffer.
*/
if (!NaClCopyInFromUser(nap, &kern_nanimh, nanimhp, sizeof kern_nanimh)) {
NaClLog(4, "NaClImcMsgHdr not in user address space\n");
retval = -NACL_ABI_EFAULT;
goto cleanup_leave;
}
/* copy before validating */
if (kern_nanimh.iov_length > NACL_ABI_IMC_IOVEC_MAX) {
NaClLog(4, "gather/scatter array too large: %"NACL_PRIdNACL_SIZE"\n",
kern_nanimh.iov_length);
retval = -NACL_ABI_EINVAL;
goto cleanup_leave;
}
if (kern_nanimh.desc_length > NACL_ABI_IMC_USER_DESC_MAX) {
NaClLog(4, "handle vector too long: %"NACL_PRIdNACL_SIZE"\n",
kern_nanimh.desc_length);
retval = -NACL_ABI_EINVAL;
goto cleanup_leave;
}
if (kern_nanimh.iov_length > 0) {
/*
* Copy IOV array into kernel space. Validate this snapshot and do
* user->kernel address conversions on this snapshot.
*/
if (!NaClCopyInFromUser(nap, kern_naiov, (uintptr_t) kern_nanimh.iov,
(kern_nanimh.iov_length * sizeof kern_naiov[0]))) {
NaClLog(4, "gather/scatter array not in user address space\n");
retval = -NACL_ABI_EFAULT;
goto cleanup_leave;
}
/*
* Convert every IOV base from user to system address, validate
* range of bytes are really in user address space.
*/
for (i = 0; i < kern_nanimh.iov_length; ++i) {
sysaddr = NaClUserToSysAddrRange(nap,
(uintptr_t) kern_naiov[i].base,
kern_naiov[i].length);
if (kNaClBadAddress == sysaddr) {
NaClLog(4, "iov number %"NACL_PRIuS" not entirely in user space\n", i);
retval = -NACL_ABI_EFAULT;
goto cleanup_leave;
}
kern_iov[i].base = (void *) sysaddr;
kern_iov[i].length = kern_naiov[i].length;
}
}
if (kern_nanimh.desc_length > 0) {
sysaddr = NaClUserToSysAddrRange(nap,
(uintptr_t) kern_nanimh.descv,
kern_nanimh.desc_length * sizeof(int32_t));
if (kNaClBadAddress == sysaddr) {
retval = -NACL_ABI_EFAULT;
goto cleanup_leave;
}
}
ndp = NaClAppGetDesc(nap, d);
if (NULL == ndp) {
NaClLog(4, "receiving descriptor invalid\n");
retval = -NACL_ABI_EBADF;
goto cleanup_leave;
}
recv_hdr.iov = kern_iov;
recv_hdr.iov_length = kern_nanimh.iov_length;
recv_hdr.ndescv = new_desc;
recv_hdr.ndesc_length = NACL_ARRAY_SIZE(new_desc);
memset(new_desc, 0, sizeof new_desc);
recv_hdr.flags = 0; /* just to make it obvious; IMC will clear it for us */
/* lock user memory ranges in kern_naiov */
for (i = 0; i < kern_nanimh.iov_length; ++i) {
NaClVmIoWillStart(nap,
kern_naiov[i].base,
kern_naiov[i].base + kern_naiov[i].length - 1);
}
ssize_retval = NACL_VTBL(NaClDesc, ndp)->RecvMsg(ndp, &recv_hdr, flags);
/* unlock user memory ranges in kern_naiov */
for (i = 0; i < kern_nanimh.iov_length; ++i) {
NaClVmIoHasEnded(nap,
kern_naiov[i].base,
kern_naiov[i].base + kern_naiov[i].length - 1);
}
/*
* retval is number of user payload bytes received and excludes the
* header bytes.
*/
NaClLog(3, "NaClSysImcRecvMsg: RecvMsg() returned %"NACL_PRIdS"\n",
ssize_retval);
if (NaClSSizeIsNegErrno(&ssize_retval)) {
/* negative error numbers all have valid 32-bit representations,
* so this cast is safe. */
retval = (int32_t) ssize_retval;
goto cleanup;
} else if (ssize_retval > INT32_MAX || ssize_retval < INT32_MIN) {
retval = -NACL_ABI_EOVERFLOW;
goto cleanup;
} else {
/* cast is safe due to range check above */
retval = (int32_t) ssize_retval;
}
/*
* NB: recv_hdr.flags may contain NACL_ABI_MESSAGE_TRUNCATED and/or
* NACL_ABI_HANDLES_TRUNCATED.
*/
kern_nanimh.flags = recv_hdr.flags;
/*
* Now internalize the NaClHandles as NaClDesc objects.
*/
num_user_desc = recv_hdr.ndesc_length;
if (kern_nanimh.desc_length < num_user_desc) {
kern_nanimh.flags |= NACL_ABI_RECVMSG_DESC_TRUNCATED;
for (i = kern_nanimh.desc_length; i < num_user_desc; ++i) {
NaClDescUnref(new_desc[i]);
new_desc[i] = NULL;
}
num_user_desc = kern_nanimh.desc_length;
}
invalid_desc = (struct NaClDesc *) NaClDescInvalidMake();
/* prepare to write out to user space the descriptor numbers */
for (i = 0; i < num_user_desc; ++i) {
if (invalid_desc == new_desc[i]) {
usr_desc[i] = kKnownInvalidDescNumber;
NaClDescUnref(new_desc[i]);
} else {
usr_desc[i] = NaClAppSetDescAvail(nap, new_desc[i]);
}
new_desc[i] = NULL;
}
if (0 != num_user_desc &&
!NaClCopyOutToUser(nap, (uintptr_t) kern_nanimh.descv, usr_desc,
num_user_desc * sizeof usr_desc[0])) {
NaClLog(LOG_FATAL,
("NaClSysImcRecvMsg: in/out ptr (descv %"NACL_PRIxPTR
") became invalid at copyout?\n"),
(uintptr_t) kern_nanimh.descv);
}
kern_nanimh.desc_length = num_user_desc;
if (!NaClCopyOutToUser(nap, nanimhp, &kern_nanimh, sizeof kern_nanimh)) {
NaClLog(LOG_FATAL,
"NaClSysImcRecvMsg: in/out ptr (iov) became"
" invalid at copyout?\n");
}
/* copy out updated desc count, flags */
cleanup:
if (retval < 0) {
for (i = 0; i < NACL_ARRAY_SIZE(new_desc); ++i) {
if (NULL != new_desc[i]) {
NaClDescUnref(new_desc[i]);
new_desc[i] = NULL;
}
}
}
NaClDescUnref(ndp);
NaClDescSafeUnref(invalid_desc);
NaClLog(3, "NaClSysImcRecvMsg: returning %d\n", retval);
cleanup_leave:
return retval;
}
/*
* This function converts addresses from user addresses to system
* addresses, copying into kernel space as needed to avoid TOCvTOU
* races, then invokes the descriptor's SendMsg() method.
*/
int32_t NaClSysImcSendmsg(struct NaClAppThread *natp,
int d,
uint32_t nanimhp,
int flags) {
struct NaClApp *nap = natp->nap;
int32_t retval = -NACL_ABI_EINVAL;
ssize_t ssize_retval;
uintptr_t sysaddr;
/* copy of user-space data for validation */
struct NaClAbiNaClImcMsgHdr kern_nanimh;
struct NaClAbiNaClImcMsgIoVec kern_naiov[NACL_ABI_IMC_IOVEC_MAX];
struct NaClImcMsgIoVec kern_iov[NACL_ABI_IMC_IOVEC_MAX];
int32_t usr_desc[NACL_ABI_IMC_USER_DESC_MAX];
/* kernel-side representatin of descriptors */
struct NaClDesc *kern_desc[NACL_ABI_IMC_USER_DESC_MAX];
struct NaClImcTypedMsgHdr kern_msg_hdr;
struct NaClDesc *ndp;
size_t i;
NaClLog(3,
("Entered NaClSysImcSendmsg(0x%08"NACL_PRIxPTR", %d,"
" 0x%08"NACL_PRIx32", 0x%x)\n"),
(uintptr_t) natp, d, nanimhp, flags);
if (!NaClCopyInFromUser(nap, &kern_nanimh, nanimhp, sizeof kern_nanimh)) {
NaClLog(4, "NaClImcMsgHdr not in user address space\n");
retval = -NACL_ABI_EFAULT;
goto cleanup_leave;
}
/* copy before validating contents */
/*
* Some of these checks duplicate checks that will be done in the
* nrd xfer library, but it is better to check before doing the
* address translation of memory/descriptor vectors if those vectors
* might be too long. Plus, we need to copy and validate vectors
* for TOCvTOU race protection, and we must prevent overflows. The
* nrd xfer library's checks should never fire when called from the
* service runtime, but the nrd xfer library might be called from
* other code.
*/
if (kern_nanimh.iov_length > NACL_ABI_IMC_IOVEC_MAX) {
NaClLog(4, "gather/scatter array too large\n");
retval = -NACL_ABI_EINVAL;
goto cleanup_leave;
}
if (kern_nanimh.desc_length > NACL_ABI_IMC_USER_DESC_MAX) {
NaClLog(4, "handle vector too long\n");
retval = -NACL_ABI_EINVAL;
goto cleanup_leave;
}
if (kern_nanimh.iov_length > 0) {
if (!NaClCopyInFromUser(nap, kern_naiov, (uintptr_t) kern_nanimh.iov,
(kern_nanimh.iov_length * sizeof kern_naiov[0]))) {
NaClLog(4, "gather/scatter array not in user address space\n");
retval = -NACL_ABI_EFAULT;
goto cleanup_leave;
}
for (i = 0; i < kern_nanimh.iov_length; ++i) {
sysaddr = NaClUserToSysAddrRange(nap,
(uintptr_t) kern_naiov[i].base,
kern_naiov[i].length);
if (kNaClBadAddress == sysaddr) {
retval = -NACL_ABI_EFAULT;
goto cleanup_leave;
}
kern_iov[i].base = (void *) sysaddr;
kern_iov[i].length = kern_naiov[i].length;
}
}
ndp = NaClAppGetDesc(nap, d);
if (NULL == ndp) {
retval = -NACL_ABI_EBADF;
goto cleanup_leave;
}
/*
* make things easier for cleaup exit processing
*/
memset(kern_desc, 0, sizeof kern_desc);
retval = -NACL_ABI_EINVAL;
kern_msg_hdr.iov = kern_iov;
kern_msg_hdr.iov_length = kern_nanimh.iov_length;
if (0 == kern_nanimh.desc_length) {
kern_msg_hdr.ndescv = 0;
kern_msg_hdr.ndesc_length = 0;
} else {
if (!NaClCopyInFromUser(nap, usr_desc, kern_nanimh.descv,
kern_nanimh.desc_length * sizeof usr_desc[0])) {
retval = -NACL_ABI_EFAULT;
goto cleanup;
}
for (i = 0; i < kern_nanimh.desc_length; ++i) {
if (kKnownInvalidDescNumber == usr_desc[i]) {
kern_desc[i] = (struct NaClDesc *) NaClDescInvalidMake();
} else {
/* NaCl modules are ILP32, so this works on ILP32 and LP64 systems */
kern_desc[i] = NaClAppGetDesc(nap, usr_desc[i]);
}
if (NULL == kern_desc[i]) {
retval = -NACL_ABI_EBADF;
goto cleanup;
}
}
kern_msg_hdr.ndescv = kern_desc;
kern_msg_hdr.ndesc_length = kern_nanimh.desc_length;
}
kern_msg_hdr.flags = kern_nanimh.flags;
/* lock user memory ranges in kern_naiov */
for (i = 0; i < kern_nanimh.iov_length; ++i) {
NaClVmIoWillStart(nap,
kern_naiov[i].base,
kern_naiov[i].base + kern_naiov[i].length - 1);
}
ssize_retval = NACL_VTBL(NaClDesc, ndp)->SendMsg(ndp, &kern_msg_hdr, flags);
/* unlock user memory ranges in kern_naiov */
for (i = 0; i < kern_nanimh.iov_length; ++i) {
NaClVmIoHasEnded(nap,
kern_naiov[i].base,
kern_naiov[i].base + kern_naiov[i].length - 1);
}
if (NaClSSizeIsNegErrno(&ssize_retval)) {
/*
* NaClWouldBlock uses TSD (for both the errno-based and
* GetLastError()-based implementations), so this is threadsafe.
*/
if (0 != (flags & NACL_DONT_WAIT) && NaClWouldBlock()) {
retval = -NACL_ABI_EAGAIN;
} else if (-NACL_ABI_EMSGSIZE == ssize_retval) {
/*
* Allow the caller to handle the case when imc_sendmsg fails because
* the message is too large for the system to send in one piece.
*/
retval = -NACL_ABI_EMSGSIZE;
} else {
/*
* TODO(bsy): the else case is some mysterious internal error.
* Should we destroy the ndp or otherwise mark it as bad? Was
* the failure atomic? Did it send some partial data? Linux
* implementation appears okay.
*/
retval = -NACL_ABI_EIO;
}
} else if (ssize_retval > INT32_MAX || ssize_retval < INT32_MIN) {
retval = -NACL_ABI_EOVERFLOW;
} else {
/* cast is safe due to range checks above */
retval = (int32_t)ssize_retval;
}
cleanup:
for (i = 0; i < kern_nanimh.desc_length; ++i) {
if (NULL != kern_desc[i]) {
NaClDescUnref(kern_desc[i]);
kern_desc[i] = NULL;
}
}
NaClDescUnref(ndp);
cleanup_leave:
NaClLog(3, "NaClSysImcSendmsg: returning %d\n", retval);
return retval;
}
