d/freebsd-skq
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

Rework linux accept(2). This makes the code flow easier to follow,

Browse Source 
and fixes a bug where calling accept(2) could result in closing fd 0.

Note that the code still contains a number of problems: it makes
assumptions about l_sockaddr_in being the same as sockaddr_in,
the EFAULT-related code looks like it doesn't work at all, and the
socket type check is racy.  Those will be addressed later on;
I'm trying to work in small steps to avoid breaking one thing while
fixing another.

It fixes Redis, among other things.

Reviewed by:	kib
MFC after:	2 weeks
Sponsored by:	The FreeBSD Foundation
Differential Revision:	https://reviews.freebsd.org/D25461
This commit is contained in:
trasz 2020-07-01 10:37:08 +00:00
parent e478a9ec1d
commit 967382a845
1 changed files with 32 additions and 23 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

55
sys/compat/linux/linux_socket.c
View File

@ -40,6 +40,7 @@ __FBSDID("$FreeBSD$");
#include <sys/capsicum.h> #include <sys/capsicum.h>
#include <sys/fcntl.h> #include <sys/fcntl.h>
#include <sys/file.h> #include <sys/file.h>
#include <sys/filedesc.h>
#include <sys/limits.h> #include <sys/limits.h>
#include <sys/lock.h> #include <sys/lock.h>
#include <sys/malloc.h> #include <sys/malloc.h>
@ -611,17 +612,19 @@ linux_accept_common(struct thread *td, int s, l_uintptr_t addr,
{ {
struct l_sockaddr *lsa; struct l_sockaddr *lsa;
struct sockaddr *sa; struct sockaddr *sa;
struct file *fp; struct file *fp, *fp1;
int bflags, len; int bflags, len;
struct socket *so; struct socket *so;
int error, error1; int error, error1;
bflags = 0; bflags = 0;
fp = NULL;
sa = NULL;
error = linux_set_socket_flags(flags, &bflags); error = linux_set_socket_flags(flags, &bflags);
if (error != 0) if (error != 0)
return (error); return (error);
sa = NULL;
if (PTRIN(addr) == NULL) { if (PTRIN(addr) == NULL) {
len = 0; len = 0;
error = kern_accept4(td, s, NULL, NULL, bflags, NULL); error = kern_accept4(td, s, NULL, NULL, bflags, NULL);
@ -632,48 +635,54 @@ linux_accept_common(struct thread *td, int s, l_uintptr_t addr,
if (len < 0) if (len < 0)
return (EINVAL); return (EINVAL);
error = kern_accept4(td, s, &sa, &len, bflags, &fp); error = kern_accept4(td, s, &sa, &len, bflags, &fp);
if (error == 0)
fdrop(fp, td);
} }
/*
* Translate errno values into ones used by Linux.
*/
if (error != 0) { if (error != 0) {
/* /*
* XXX. This is wrong, different sockaddr structures * XXX. This is wrong, different sockaddr structures
* have different sizes. * have different sizes.
*/ */
if (error == EFAULT && namelen != sizeof(struct sockaddr_in)) switch (error) {
{ case EFAULT:
error = EINVAL; if (namelen != sizeof(struct sockaddr_in))
goto out; error = EINVAL;
} break;
if (error == EINVAL) { case EINVAL:
error1 = getsock_cap(td, s, &cap_accept_rights, &fp, NULL, NULL); error1 = getsock_cap(td, s, &cap_accept_rights, &fp1, NULL, NULL);
if (error1 != 0) { if (error1 != 0) {
error = error1; error = error1;
goto out; break;
} }
so = fp->f_data; so = fp1->f_data;
if (so->so_type == SOCK_DGRAM) if (so->so_type == SOCK_DGRAM)
error = EOPNOTSUPP; error = EOPNOTSUPP;
fdrop(fp, td); fdrop(fp1, td);
break;
} }
goto out; return (error);
} }
if (len != 0 && error == 0) { if (len != 0) {
error = bsd_to_linux_sockaddr(sa, &lsa, len); error = bsd_to_linux_sockaddr(sa, &lsa, len);
if (error == 0) if (error == 0)
error = copyout(lsa, PTRIN(addr), len); error = copyout(lsa, PTRIN(addr), len);
free(lsa, M_SONAME); free(lsa, M_SONAME);
}
/*
* XXX: We should also copyout the len, shouldn't we?
*/
if (error != 0) {
fdclose(td, fp, td->td_retval[0]);
td->td_retval[0] = 0;
}
}
if (fp != NULL)
fdrop(fp, td);
free(sa, M_SONAME); free(sa, M_SONAME);
out:
if (error != 0) {
(void)kern_close(td, td->td_retval[0]);
td->td_retval[0] = 0;
}
return (error); return (error);
} }