- Add conditional VFS Giant locking to getdents_common() (linux ABIs),

  ibcs2_getdents(), ibcs2_read(), ogetdirentries(), svr4_sys_getdents(),
  and svr4_sys_getdents64() similar to that in getdirentries().
- Mark ibcs2_getdents(), ibcs2_read(), linux_getdents(), linux_getdents64(),
  linux_readdir(), ogetdirentries(), svr4_sys_getdents(), and
  svr4_sys_getdents64() MPSAFE.

10 files changed, 63 insertions, 33 deletions

diff --git a/sys/amd64/linux32/syscalls.master b/sys/amd64/linux32/syscalls.master
index 4fa88e5..6cfbcb0 100644
--- a/sys/amd64/linux32/syscalls.master
+++ b/sys/amd64/linux32/syscalls.master
@@ -169,7 +169,7 @@
 87	AUE_SWAPON	MNOPROTO	{ int swapon(char *name); }
 88	AUE_REBOOT	MSTD	{ int linux_reboot(l_int magic1, \
 				    l_int magic2, l_uint cmd, void *arg); }
-89	AUE_O_GETDENTS	STD	{ int linux_readdir(l_uint fd, \
+89	AUE_O_GETDENTS	MSTD	{ int linux_readdir(l_uint fd, \
 				    struct l_dirent *dent, l_uint count); }
 90	AUE_MMAP	MSTD	{ int linux_mmap(struct l_mmap_argv *ptr); }
 91	AUE_MUNMAP	MNOPROTO	{ int munmap(caddr_t addr, int len); }
@@ -246,7 +246,7 @@
 140	AUE_LSEEK	MSTD	{ int linux_llseek(l_int fd, l_ulong ohigh, \
 				    l_ulong olow, l_loff_t *res, \
 				    l_uint whence); }
-141	AUE_O_GETDENTS	STD	{ int linux_getdents(l_uint fd, void *dent, \
+141	AUE_O_GETDENTS	MSTD	{ int linux_getdents(l_uint fd, void *dent, \
 				    l_uint count); }
 142	AUE_SELECT	MSTD	{ int linux_select(l_int nfds, \
 				    l_fd_set *readfds, l_fd_set *writefds, \
@@ -381,7 +381,7 @@
 				    l_size_t len, u_char *vec); }
 219	AUE_MADVISE	MNOPROTO { int madvise(void *addr, size_t len, \
 				    int behav); }
-220	AUE_O_GETDENTS	STD	{ int linux_getdents64(l_uint fd, \
+220	AUE_O_GETDENTS	MSTD	{ int linux_getdents64(l_uint fd, \
 				    void *dirent, l_uint count); }
 221	AUE_FCNTL	MSTD	{ int linux_fcntl64(l_uint fd, l_uint cmd, \
 				    uintptr_t arg); }
diff --git a/sys/compat/linux/linux_file.c b/sys/compat/linux/linux_file.c
index ca6b7a6..cd50aa4 100644
--- a/sys/compat/linux/linux_file.c
+++ b/sys/compat/linux/linux_file.c
@@ -259,7 +259,17 @@ getdents_common(struct thread *td, struct linux_getdents64_args *args,
 	struct l_dirent64 linux_dirent64;
 	int buflen, error, eofflag, nbytes, justone;
 	u_long *cookies = NULL, *cookiep;
-	int ncookies;
+	int ncookies, vfslocked;
+
+	nbytes = args->count;
+	if (nbytes == 1) {
+		/* readdir(2) case. Always struct dirent. */
+		if (is64bit)
+			return (EINVAL);
+		nbytes = sizeof(linux_dirent);
+		justone = 1;
+	} else
+		justone = 0;
 
 	if ((error = getvnode(td->td_proc->p_fd, args->fd, &fp)) != 0)
 		return (error);
@@ -270,23 +280,13 @@ getdents_common(struct thread *td, struct linux_getdents64_args *args,
 	}
 
 	vp = fp->f_vnode;
+	vfslocked = VFS_LOCK_GIANT(vp->v_mount);
 	if (vp->v_type != VDIR) {
+		VFS_UNLOCK_GIANT(vfslocked);
 		fdrop(fp, td);
 		return (EINVAL);
 	}
 
-	nbytes = args->count;
-	if (nbytes == 1) {
-		/* readdir(2) case. Always struct dirent. */
-		if (is64bit) {
-			fdrop(fp, td);
-			return (EINVAL);
-		}
-		nbytes = sizeof(linux_dirent);
-		justone = 1;
-	} else
-		justone = 0;
-
 	off = fp->f_offset;
 
 	buflen = max(LINUX_DIRBLKSIZ, nbytes);
@@ -439,6 +439,7 @@ out:
 		free(cookies, M_TEMP);
 
 	VOP_UNLOCK(vp, 0, td);
+	VFS_UNLOCK_GIANT(vfslocked);
 	fdrop(fp, td);
 	free(buf, M_TEMP);
 	return (error);
diff --git a/sys/compat/svr4/svr4_misc.c b/sys/compat/svr4/svr4_misc.c
index affe6eb..00abe84 100644
--- a/sys/compat/svr4/svr4_misc.c
+++ b/sys/compat/svr4/svr4_misc.c
@@ -240,7 +240,7 @@ svr4_sys_getdents64(td, uap)
 	struct iovec aiov;
 	off_t off;
 	struct svr4_dirent64 svr4_dirent;
-	int buflen, error, eofflag, nbytes, justone;
+	int buflen, error, eofflag, nbytes, justone, vfslocked;
 	u_long *cookies = NULL, *cookiep;
 	int ncookies;
 
@@ -256,8 +256,9 @@ svr4_sys_getdents64(td, uap)
 	}
 
 	vp = fp->f_vnode;
-
+	vfslocked = VFS_LOCK_GIANT(vp->v_mount);
 	if (vp->v_type != VDIR) {
+		VFS_UNLOCK_GIANT(vfslocked);
 		fdrop(fp, td);
 		return (EINVAL);
 	}
@@ -394,6 +395,7 @@ eof:
 	td->td_retval[0] = nbytes - resid;
 out:
 	VOP_UNLOCK(vp, 0, td);
+	VFS_UNLOCK_GIANT(vfslocked);
 	fdrop(fp, td);
 	if (cookies)
 		free(cookies, M_TEMP);
@@ -418,7 +420,7 @@ svr4_sys_getdents(td, uap)
 	struct iovec aiov;
 	struct svr4_dirent idb;
 	off_t off;		/* true file offset */
-	int buflen, error, eofflag;
+	int buflen, error, eofflag, vfslocked;
 	u_long *cookiebuf = NULL, *cookie;
 	int ncookies = 0, *retval = td->td_retval;
 
@@ -434,7 +436,9 @@ svr4_sys_getdents(td, uap)
 	}
 
 	vp = fp->f_vnode;
+	vfslocked = VFS_LOCK_GIANT(vp->v_mount);
 	if (vp->v_type != VDIR) {
+		VFS_UNLOCK_GIANT(vfslocked);
 		fdrop(fp, td);
 		return (EINVAL);
 	}
@@ -524,6 +528,7 @@ eof:
 	*retval = uap->nbytes - resid;
 out:
 	VOP_UNLOCK(vp, 0, td);
+	VFS_UNLOCK_GIANT(vfslocked);
 	fdrop(fp, td);
 	if (cookiebuf)
 		free(cookiebuf, M_TEMP);
diff --git a/sys/compat/svr4/syscalls.master b/sys/compat/svr4/syscalls.master
index 32a1541..344b0c2 100644
--- a/sys/compat/svr4/syscalls.master
+++ b/sys/compat/svr4/syscalls.master
@@ -136,7 +136,7 @@
 78	AUE_NULL	UNIMPL	rfsys
 79	AUE_NULL	MNOPROTO	{ int rmdir(char *path); }
 80	AUE_NULL	MNOPROTO	{ int mkdir(char *path, int mode); }
-81	AUE_NULL	STD	{ int svr4_sys_getdents(int fd, char *buf, \
+81	AUE_NULL	MSTD	{ int svr4_sys_getdents(int fd, char *buf, \
 				    int nbytes); }
 82	AUE_NULL	UNIMPL	libattach
 83	AUE_NULL	UNIMPL	libdetach
@@ -325,7 +325,7 @@
 210	AUE_NULL	UNIMPL	signotifywait
 211	AUE_NULL	UNIMPL	lwp_sigredirect
 212	AUE_NULL	UNIMPL	lwp_alarm
-213	AUE_NULL	STD	{ int svr4_sys_getdents64(int fd, \
+213	AUE_NULL	MSTD	{ int svr4_sys_getdents64(int fd, \
 				    struct svr4_dirent64 *dp, int nbytes); }
 ;213	AUE_NULL	UNIMPL	getdents64
 214	AUE_NULL	MSTD	{ caddr_t svr4_sys_mmap64(void *addr, \
diff --git a/sys/i386/ibcs2/ibcs2_misc.c b/sys/i386/ibcs2/ibcs2_misc.c
index c875075..042505f 100644
--- a/sys/i386/ibcs2/ibcs2_misc.c
+++ b/sys/i386/ibcs2/ibcs2_misc.c
@@ -329,7 +329,7 @@ ibcs2_getdents(td, uap)
 	struct iovec aiov;
 	struct ibcs2_dirent idb;
 	off_t off;			/* true file offset */
-	int buflen, error, eofflag;
+	int buflen, error, eofflag, vfslocked;
 	u_long *cookies = NULL, *cookiep;
 	int ncookies;
 #define	BSD_DIRENT(cp)		((struct dirent *)(cp))
@@ -342,7 +342,9 @@ ibcs2_getdents(td, uap)
 		return (EBADF);
 	}
 	vp = fp->f_vnode;
+	vfslocked = VFS_LOCK_GIANT(vp->v_mount);
 	if (vp->v_type != VDIR) {	/* XXX  vnode readdir op should do this */
+		VFS_UNLOCK_GIANT(vfslocked);
 		fdrop(fp, td);
 		return (EINVAL);
 	}
@@ -459,6 +461,7 @@ eof:
 	td->td_retval[0] = uap->nbytes - resid;
 out:
 	VOP_UNLOCK(vp, 0, td);
+	VFS_UNLOCK_GIANT(vfslocked);
 	fdrop(fp, td);
 	if (cookies)
 		free(cookies, M_TEMP);
@@ -484,7 +487,7 @@ ibcs2_read(td, uap)
 		char name[14];
 	} idb;
 	off_t off;			/* true file offset */
-	int buflen, error, eofflag, size;
+	int buflen, error, eofflag, size, vfslocked;
 	u_long *cookies = NULL, *cookiep;
 	int ncookies;
 
@@ -499,7 +502,9 @@ ibcs2_read(td, uap)
 		return (EBADF);
 	}
 	vp = fp->f_vnode;
+	vfslocked = VFS_LOCK_GIANT(vp->v_mount);
 	if (vp->v_type != VDIR) {
+		VFS_UNLOCK_GIANT(vfslocked);
 		fdrop(fp, td);
 		return read(td, (struct read_args *)uap);
 	}
@@ -622,6 +627,7 @@ eof:
 	td->td_retval[0] = uap->nbytes - resid;
 out:
 	VOP_UNLOCK(vp, 0, td);
+	VFS_UNLOCK_GIANT(vfslocked);
 	fdrop(fp, td);
 	if (cookies)
 		free(cookies, M_TEMP);
diff --git a/sys/i386/ibcs2/syscalls.master b/sys/i386/ibcs2/syscalls.master
index ed79cb5..fe4302e6 100644
--- a/sys/i386/ibcs2/syscalls.master
+++ b/sys/i386/ibcs2/syscalls.master
@@ -39,7 +39,7 @@
 1	AUE_EXIT	MNOPROTO { void sys_exit(int rval); } exit \
 				    sys_exit_args void
 2	AUE_FORK	MNOPROTO { int fork(void); }
-3	AUE_NULL	STD	{ int ibcs2_read(int fd, char *buf, \
+3	AUE_NULL	MSTD	{ int ibcs2_read(int fd, char *buf, \
 				    u_int nbytes); }
 4	AUE_NULL	MNOPROTO { int write(int fd, char *buf, \
 				    u_int nbytes); }
@@ -146,7 +146,7 @@
 78	AUE_NULL	UNIMPL	rfs_rfsys
 79	AUE_RMDIR	MSTD	{ int ibcs2_rmdir(char *path); }
 80	AUE_MKDIR	MSTD	{ int ibcs2_mkdir(char *path, int mode); }
-81	AUE_GETDIRENTRIES	STD	{ int ibcs2_getdents(int fd, char *buf, \
+81	AUE_GETDIRENTRIES	MSTD	{ int ibcs2_getdents(int fd, char *buf, \
 				    int nbytes); }
 82	AUE_NULL	UNIMPL	nosys
 83	AUE_NULL	UNIMPL	nosys
diff --git a/sys/i386/linux/syscalls.master b/sys/i386/linux/syscalls.master
index 6d30f68..6365f7b 100644
--- a/sys/i386/linux/syscalls.master
+++ b/sys/i386/linux/syscalls.master
@@ -169,7 +169,7 @@
 87	AUE_SWAPON	MNOPROTO	{ int swapon(char *name); }
 88	AUE_REBOOT	MSTD	{ int linux_reboot(l_int magic1, \
 				    l_int magic2, l_uint cmd, void *arg); }
-89	AUE_O_GETDENTS	STD	{ int linux_readdir(l_uint fd, \
+89	AUE_O_GETDENTS	MSTD	{ int linux_readdir(l_uint fd, \
 				    struct l_dirent *dent, l_uint count); }
 90	AUE_MMAP	MSTD	{ int linux_mmap(struct l_mmap_argv *ptr); }
 91	AUE_MUNMAP	MNOPROTO	{ int munmap(caddr_t addr, int len); }
@@ -248,7 +248,7 @@
 140	AUE_LSEEK	MSTD	{ int linux_llseek(l_int fd, l_ulong ohigh, \
 				    l_ulong olow, l_loff_t *res, \
 				    l_uint whence); }
-141	AUE_O_GETDENTS	STD	{ int linux_getdents(l_uint fd, void *dent, \
+141	AUE_O_GETDENTS	MSTD	{ int linux_getdents(l_uint fd, void *dent, \
 				    l_uint count); }
 142	AUE_SELECT	MSTD	{ int linux_select(l_int nfds, \
 				    l_fd_set *readfds, l_fd_set *writefds, \
@@ -383,7 +383,7 @@
 				    l_size_t len, u_char *vec); }
 219	AUE_MADVISE	MNOPROTO { int madvise(void *addr, size_t len, \
 				    int behav); }
-220	AUE_O_GETDENTS	STD	{ int linux_getdents64(l_uint fd, \
+220	AUE_O_GETDENTS	MSTD	{ int linux_getdents64(l_uint fd, \
 				    void *dirent, l_uint count); }
 221	AUE_FCNTL	MSTD	{ int linux_fcntl64(l_uint fd, l_uint cmd, \
 				    l_ulong arg); }
diff --git a/sys/kern/syscalls.master b/sys/kern/syscalls.master
index ba53824..ecd8c8f 100644
--- a/sys/kern/syscalls.master
+++ b/sys/kern/syscalls.master
@@ -304,7 +304,7 @@
 154	AUE_NULL	UNIMPL	nosys
 ; 155 is initialized by the NFS code, if present.
 155	AUE_NFSSVC	MNOIMPL	{ int nfssvc(int flag, caddr_t argp); }
-156	AUE_GETDIRENTRIES	COMPAT	{ int getdirentries(int fd, char *buf, \
+156	AUE_GETDIRENTRIES	MCOMPAT	{ int getdirentries(int fd, char *buf, \
 				    u_int count, long *basep); }
 157	AUE_STATFS	MCOMPAT4	{ int statfs(char *path, \
 				    struct ostatfs *buf); }
diff --git a/sys/kern/vfs_extattr.c b/sys/kern/vfs_extattr.c
index 4d6868c..e9f83f0 100644
--- a/sys/kern/vfs_extattr.c
+++ b/sys/kern/vfs_extattr.c
@@ -3569,7 +3569,7 @@ ogetdirentries(td, uap)
 	struct iovec aiov, kiov;
 	struct dirent *dp, *edp;
 	caddr_t dirbuf;
-	int error, eofflag, readcnt;
+	int error, eofflag, readcnt, vfslocked;
 	long loff;
 
 	/* XXX arbitrary sanity limit on `count'. */
@@ -3583,7 +3583,9 @@ ogetdirentries(td, uap)
 	}
 	vp = fp->f_vnode;
 unionread:
+	vfslocked = VFS_LOCK_GIANT(vp->v_mount);
 	if (vp->v_type != VDIR) {
+		VFS_UNLOCK_GIANT(vfslocked);
 		fdrop(fp, td);
 		return (EINVAL);
 	}
@@ -3601,6 +3603,7 @@ unionread:
 	error = mac_check_vnode_readdir(td->td_ucred, vp);
 	if (error) {
 		VOP_UNLOCK(vp, 0, td);
+		VFS_UNLOCK_GIANT(vfslocked);
 		fdrop(fp, td);
 		return (error);
 	}
@@ -3658,15 +3661,19 @@ unionread:
 	}
 	VOP_UNLOCK(vp, 0, td);
 	if (error) {
+		VFS_UNLOCK_GIANT(vfslocked);
 		fdrop(fp, td);
 		return (error);
 	}
 	if (uap->count == auio.uio_resid) {
 		if (union_dircheckp) {
 			error = union_dircheckp(td, &vp, fp);
-			if (error == -1)
+			if (error == -1) {
+				VFS_UNLOCK_GIANT(vfslocked);
 				goto unionread;
+			}
 			if (error) {
+				VFS_UNLOCK_GIANT(vfslocked);
 				fdrop(fp, td);
 				return (error);
 			}
@@ -3685,10 +3692,12 @@ unionread:
 			fp->f_data = vp;
 			fp->f_offset = 0;
 			vput(tvp);
+			VFS_UNLOCK_GIANT(vfslocked);
 			goto unionread;
 		}
 		VOP_UNLOCK(vp, 0, td);
 	}
+	VFS_UNLOCK_GIANT(vfslocked);
 	error = copyout(&loff, uap->basep, sizeof(long));
 	fdrop(fp, td);
 	td->td_retval[0] = uap->count - auio.uio_resid;
diff --git a/sys/kern/vfs_syscalls.c b/sys/kern/vfs_syscalls.c
index 4d6868c..e9f83f0 100644
--- a/sys/kern/vfs_syscalls.c
+++ b/sys/kern/vfs_syscalls.c
@@ -3569,7 +3569,7 @@ ogetdirentries(td, uap)
 	struct iovec aiov, kiov;
 	struct dirent *dp, *edp;
 	caddr_t dirbuf;
-	int error, eofflag, readcnt;
+	int error, eofflag, readcnt, vfslocked;
 	long loff;
 
 	/* XXX arbitrary sanity limit on `count'. */
@@ -3583,7 +3583,9 @@ ogetdirentries(td, uap)
 	}
 	vp = fp->f_vnode;
 unionread:
+	vfslocked = VFS_LOCK_GIANT(vp->v_mount);
 	if (vp->v_type != VDIR) {
+		VFS_UNLOCK_GIANT(vfslocked);
 		fdrop(fp, td);
 		return (EINVAL);
 	}
@@ -3601,6 +3603,7 @@ unionread:
 	error = mac_check_vnode_readdir(td->td_ucred, vp);
 	if (error) {
 		VOP_UNLOCK(vp, 0, td);
+		VFS_UNLOCK_GIANT(vfslocked);
 		fdrop(fp, td);
 		return (error);
 	}
@@ -3658,15 +3661,19 @@ unionread:
 	}
 	VOP_UNLOCK(vp, 0, td);
 	if (error) {
+		VFS_UNLOCK_GIANT(vfslocked);
 		fdrop(fp, td);
 		return (error);
 	}
 	if (uap->count == auio.uio_resid) {
 		if (union_dircheckp) {
 			error = union_dircheckp(td, &vp, fp);
-			if (error == -1)
+			if (error == -1) {
+				VFS_UNLOCK_GIANT(vfslocked);
 				goto unionread;
+			}
 			if (error) {
+				VFS_UNLOCK_GIANT(vfslocked);
 				fdrop(fp, td);
 				return (error);
 			}
@@ -3685,10 +3692,12 @@ unionread:
 			fp->f_data = vp;
 			fp->f_offset = 0;
 			vput(tvp);
+			VFS_UNLOCK_GIANT(vfslocked);
 			goto unionread;
 		}
 		VOP_UNLOCK(vp, 0, td);
 	}
+	VFS_UNLOCK_GIANT(vfslocked);
 	error = copyout(&loff, uap->basep, sizeof(long));
 	fdrop(fp, td);
 	td->td_retval[0] = uap->count - auio.uio_resid;