Ensure that directory entry padding bytes are zeroed.

Directory entries must be padded to maintain alignment; in many
filesystems the padding was not initialized, resulting in stack
memory being copied out to userspace.  With the ino64 work there
are also some explicit pad fields in struct dirent.  Add a subroutine
to clear these bytes and use it in the in-tree filesystems.  The
NFS client is omitted for now as it was fixed separately in r340787.

Reported by:	Thomas Barabosch, Fraunhofer FKIE
Reviewed by:	kib
MFC after:	3 days
Sponsored by:	The FreeBSD Foundation
This commit is contained in:
Mark Johnston 2018-11-23 22:24:59 +00:00
parent 759436eb7c
commit 6d2e2df764
20 changed files with 50 additions and 33 deletions

View File

@ -262,9 +262,9 @@ sfs_readdir_common(uint64_t parent_id, uint64_t id, struct vop_readdir_args *ap,
entry.d_fileno = id;
entry.d_type = DT_DIR;
entry.d_name[0] = '.';
entry.d_name[1] = '\0';
entry.d_namlen = 1;
entry.d_reclen = sizeof(entry);
dirent_terminate(&entry);
error = vfs_read_dirent(ap, &entry, uio->uio_offset);
if (error != 0)
return (SET_ERROR(error));
@ -277,9 +277,9 @@ sfs_readdir_common(uint64_t parent_id, uint64_t id, struct vop_readdir_args *ap,
entry.d_type = DT_DIR;
entry.d_name[0] = '.';
entry.d_name[1] = '.';
entry.d_name[2] = '\0';
entry.d_namlen = 2;
entry.d_reclen = sizeof(entry);
dirent_terminate(&entry);
error = vfs_read_dirent(ap, &entry, uio->uio_offset);
if (error != 0)
return (SET_ERROR(error));
@ -694,6 +694,7 @@ zfsctl_root_readdir(ap)
strcpy(entry.d_name, node->snapdir->sn_name);
entry.d_namlen = strlen(entry.d_name);
entry.d_reclen = sizeof(entry);
dirent_terminate(&entry);
error = vfs_read_dirent(ap, &entry, uio->uio_offset);
if (error != 0) {
if (error == ENAMETOOLONG)
@ -1099,6 +1100,7 @@ zfsctl_snapdir_readdir(ap)
entry.d_reclen = sizeof(entry);
/* NOTE: d_off is the offset for the *next* entry. */
entry.d_off = cookie + dots_offset;
dirent_terminate(&entry);
error = vfs_read_dirent(ap, &entry, uio->uio_offset);
if (error != 0) {
if (error == ENAMETOOLONG)

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@ -2547,6 +2547,7 @@ zfs_readdir(vnode_t *vp, uio_t *uio, cred_t *cr, int *eofp, int *ncookies, u_lon
next = &odp->d_off;
(void) strlcpy(odp->d_name, zap.za_name, odp->d_namlen + 1);
odp->d_type = type;
dirent_terminate(odp);
odp = (dirent64_t *)((intptr_t)odp + reclen);
}
outcount += reclen;

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@ -34,6 +34,7 @@
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/condvar.h>
#include <sys/dirent.h>
@ -44,7 +45,6 @@ __FBSDID("$FreeBSD$");
#include <sys/namei.h>
#include <sys/signalvar.h>
#include <sys/stat.h>
#include <sys/systm.h>
#include <sys/taskqueue.h>
#include <sys/tree.h>
#include <sys/vnode.h>
@ -354,14 +354,11 @@ autofs_readdir_one(struct uio *uio, const char *name, int fileno,
size_t *reclenp)
{
struct dirent dirent;
size_t namlen, padded_namlen, reclen;
size_t namlen, reclen;
int error;
namlen = strlen(name);
padded_namlen = roundup2(namlen + 1, __alignof(struct dirent));
KASSERT(padded_namlen <= MAXNAMLEN, ("%zd > MAXNAMLEN", padded_namlen));
reclen = offsetof(struct dirent, d_name) + padded_namlen;
reclen = _GENERIC_DIRLEN(namlen);
if (reclenp != NULL)
*reclenp = reclen;
@ -376,7 +373,7 @@ autofs_readdir_one(struct uio *uio, const char *name, int fileno,
dirent.d_type = DT_DIR;
dirent.d_namlen = namlen;
memcpy(dirent.d_name, name, namlen);
memset(dirent.d_name + namlen, 0, padded_namlen - namlen);
dirent_terminate(&dirent);
error = uiomove(&dirent, reclen, uio);
return (error);

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@ -380,8 +380,8 @@ iso_uiodir(idp,dp,off)
{
int error;
dp->d_name[dp->d_namlen] = 0;
dp->d_reclen = GENERIC_DIRSIZ(dp);
dirent_terminate(dp);
if (idp->uio->uio_resid < dp->d_reclen) {
idp->eofflag = 0;

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@ -226,7 +226,7 @@ devfs_newdirent(char *name, int namelen)
de->de_dirent->d_namlen = namelen;
de->de_dirent->d_reclen = GENERIC_DIRSIZ(&d);
bcopy(name, de->de_dirent->d_name, namelen);
de->de_dirent->d_name[namelen] = '\0';
dirent_terminate(de->de_dirent);
vfs_timestamp(&de->de_ctime);
de->de_mtime = de->de_atime = de->de_ctime;
de->de_links = 1;

View File

@ -223,9 +223,9 @@ ext2_readdir(struct vop_readdir_args *ap)
dstdp.d_fileno = dp->e2d_ino;
dstdp.d_reclen = GENERIC_DIRSIZ(&dstdp);
bcopy(dp->e2d_name, dstdp.d_name, dstdp.d_namlen);
dstdp.d_name[dstdp.d_namlen] = '\0';
/* NOTE: d_off is the offset of the *next* entry. */
dstdp.d_off = offset + dp->e2d_reclen;
dirent_terminate(&dstdp);
if (dstdp.d_reclen > uio->uio_resid) {
if (uio->uio_resid == startresid)
error = EINVAL;

View File

@ -561,8 +561,8 @@ fdesc_readdir(struct vop_readdir_args *ap)
dp->d_namlen = i + 1;
dp->d_reclen = UIO_MX;
bcopy("..", dp->d_name, dp->d_namlen);
dp->d_name[i + 1] = '\0';
dp->d_type = DT_DIR;
dirent_terminate(dp);
break;
default:
if (fdp->fd_ofiles[fcnt].fde_file == NULL)
@ -572,6 +572,7 @@ fdesc_readdir(struct vop_readdir_args *ap)
dp->d_type = (fmp->flags & FMNT_LINRDLNKF) == 0 ?
DT_CHR : DT_LNK;
dp->d_fileno = i + FD_DESC;
dirent_terminate(dp);
break;
}
/* NOTE: d_off is the offset of the *next* entry. */

View File

@ -357,7 +357,7 @@ fuse_internal_readdir_processdata(struct uio *uio,
memcpy((char *)cookediov->base + sizeof(struct dirent) -
MAXNAMLEN - 1,
(char *)buf + FUSE_NAME_OFFSET, fudge->namelen);
((char *)cookediov->base)[bytesavail - 1] = '\0';
dirent_terminate(de);
err = uiomove(cookediov->base, cookediov->len, uio);
if (err) {

View File

@ -1550,16 +1550,18 @@ msdosfs_readdir(struct vop_readdir_args *ap)
switch (n) {
case 0:
dirbuf.d_namlen = 1;
strcpy(dirbuf.d_name, ".");
dirbuf.d_name[0] = '.';
break;
case 1:
dirbuf.d_namlen = 2;
strcpy(dirbuf.d_name, "..");
dirbuf.d_name[0] = '.';
dirbuf.d_name[1] = '.';
break;
}
dirbuf.d_reclen = GENERIC_DIRSIZ(&dirbuf);
/* NOTE: d_off is the offset of the *next* entry. */
dirbuf.d_off = offset + sizeof(struct direntry);
dirent_terminate(&dirbuf);
if (uio->uio_resid < dirbuf.d_reclen)
goto out;
error = uiomove(&dirbuf, dirbuf.d_reclen, uio);

View File

@ -1226,7 +1226,6 @@ nandfs_readdir(struct vop_readdir_args *ap)
ndirent = (struct nandfs_dir_entry *)pos;
name_len = ndirent->name_len;
memset(&dirent, 0, sizeof(struct dirent));
dirent.d_fileno = ndirent->inode;
if (dirent.d_fileno) {
dirent.d_type = ndirent->file_type;
@ -1235,6 +1234,7 @@ nandfs_readdir(struct vop_readdir_args *ap)
dirent.d_reclen = GENERIC_DIRSIZ(&dirent);
/* NOTE: d_off is the offset of the *next* entry. */
dirent.d_off = diroffset + ndirent->rec_len;
dirent_terminate(&dirent);
DPRINTF(READDIR, ("copying `%*.*s`\n", name_len,
name_len, dirent.d_name));
}
@ -1243,12 +1243,12 @@ nandfs_readdir(struct vop_readdir_args *ap)
* If there isn't enough space in the uio to return a
* whole dirent, break off read
*/
if (uio->uio_resid < GENERIC_DIRSIZ(&dirent))
if (uio->uio_resid < dirent.d_reclen)
break;
/* Transfer */
if (dirent.d_fileno)
uiomove(&dirent, GENERIC_DIRSIZ(&dirent), uio);
uiomove(&dirent, dirent.d_reclen, uio);
/* Advance */
diroffset += ndirent->rec_len;

View File

@ -828,7 +828,6 @@ pfs_readdir(struct vop_readdir_args *va)
/* PFS_DELEN was picked to fit PFS_NAMLEN */
for (i = 0; i < PFS_NAMELEN - 1 && pn->pn_name[i] != '\0'; ++i)
pfsent->entry.d_name[i] = pn->pn_name[i];
pfsent->entry.d_name[i] = 0;
pfsent->entry.d_namlen = i;
/* NOTE: d_off is the offset of the *next* entry. */
pfsent->entry.d_off = offset + PFS_DELEN;
@ -855,6 +854,7 @@ pfs_readdir(struct vop_readdir_args *va)
panic("%s has unexpected node type: %d", pn->pn_name, pn->pn_type);
}
PFS_TRACE(("%s", pfsent->entry.d_name));
dirent_terminate(&pfsent->entry);
STAILQ_INSERT_TAIL(&lst, pfsent, link);
offset += PFS_DELEN;
resid -= PFS_DELEN;

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@ -106,8 +106,8 @@ smbfs_readvdir(struct vnode *vp, struct uio *uio, struct ucred *cred)
de.d_namlen = offset + 1;
de.d_name[0] = '.';
de.d_name[1] = '.';
de.d_name[offset + 1] = '\0';
de.d_type = DT_DIR;
dirent_terminate(&de);
error = uiomove(&de, DE_SIZE, uio);
if (error)
goto out;
@ -156,7 +156,7 @@ smbfs_readvdir(struct vnode *vp, struct uio *uio, struct ucred *cred)
de.d_type = (ctx->f_attr.fa_attr & SMB_FA_DIR) ? DT_DIR : DT_REG;
de.d_namlen = ctx->f_nmlen;
bcopy(ctx->f_name, de.d_name, de.d_namlen);
de.d_name[de.d_namlen] = '\0';
dirent_terminate(&de);
if (smbfs_fastlookup) {
error = smbfs_nget(vp->v_mount, vp, ctx->f_name,
ctx->f_nmlen, &ctx->f_attr, &newvp);

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@ -39,6 +39,7 @@
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/dirent.h>
#include <sys/fnv_hash.h>
#include <sys/lock.h>
@ -50,7 +51,6 @@ __FBSDID("$FreeBSD$");
#include <sys/random.h>
#include <sys/rwlock.h>
#include <sys/stat.h>
#include <sys/systm.h>
#include <sys/sysctl.h>
#include <sys/vnode.h>
#include <sys/vmmeter.h>
@ -1120,8 +1120,8 @@ tmpfs_dir_getdotdent(struct tmpfs_node *node, struct uio *uio)
dent.d_type = DT_DIR;
dent.d_namlen = 1;
dent.d_name[0] = '.';
dent.d_name[1] = '\0';
dent.d_reclen = GENERIC_DIRSIZ(&dent);
dirent_terminate(&dent);
if (dent.d_reclen > uio->uio_resid)
error = EJUSTRETURN;
@ -1164,8 +1164,8 @@ tmpfs_dir_getdotdotdent(struct tmpfs_node *node, struct uio *uio)
dent.d_namlen = 2;
dent.d_name[0] = '.';
dent.d_name[1] = '.';
dent.d_name[2] = '\0';
dent.d_reclen = GENERIC_DIRSIZ(&dent);
dirent_terminate(&dent);
if (dent.d_reclen > uio->uio_resid)
error = EJUSTRETURN;
@ -1285,8 +1285,8 @@ tmpfs_dir_getdents(struct tmpfs_node *node, struct uio *uio, int maxcookies,
d.d_namlen = de->td_namelen;
MPASS(de->td_namelen < sizeof(d.d_name));
(void)memcpy(d.d_name, de->ud.td_name, de->td_namelen);
d.d_name[de->td_namelen] = '\0';
d.d_reclen = GENERIC_DIRSIZ(&d);
dirent_terminate(&d);
/* Stop reading if the directory entry we are treating is
* bigger than the amount of data that can be returned. */

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@ -46,6 +46,7 @@
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/dirent.h>
#include <sys/limits.h>
#include <sys/lock.h>
@ -56,7 +57,6 @@ __FBSDID("$FreeBSD$");
#include <sys/kernel.h>
#include <sys/rwlock.h>
#include <sys/stat.h>
#include <sys/systm.h>
#include <sys/sysctl.h>
#include <sys/vnode.h>

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@ -39,6 +39,7 @@
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/dirent.h>
#include <sys/fcntl.h>
#include <sys/limits.h>
@ -51,7 +52,6 @@ __FBSDID("$FreeBSD$");
#include <sys/rwlock.h>
#include <sys/sched.h>
#include <sys/stat.h>
#include <sys/systm.h>
#include <sys/sysctl.h>
#include <sys/unistd.h>
#include <sys/vnode.h>

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@ -843,10 +843,10 @@ udf_readdir(struct vop_readdir_args *a)
dir.d_fileno = node->hash_id;
dir.d_type = DT_DIR;
dir.d_name[0] = '.';
dir.d_name[1] = '\0';
dir.d_namlen = 1;
dir.d_reclen = GENERIC_DIRSIZ(&dir);
dir.d_off = 1;
dirent_terminate(&dir);
uiodir.dirent = &dir;
error = udf_uiodir(&uiodir, dir.d_reclen, uio, 1);
if (error)
@ -856,10 +856,10 @@ udf_readdir(struct vop_readdir_args *a)
dir.d_type = DT_DIR;
dir.d_name[0] = '.';
dir.d_name[1] = '.';
dir.d_name[2] = '\0';
dir.d_namlen = 2;
dir.d_reclen = GENERIC_DIRSIZ(&dir);
dir.d_off = 2;
dirent_terminate(&dir);
uiodir.dirent = &dir;
error = udf_uiodir(&uiodir, dir.d_reclen, uio, 2);
} else {
@ -870,6 +870,7 @@ udf_readdir(struct vop_readdir_args *a)
DT_DIR : DT_UNKNOWN;
dir.d_reclen = GENERIC_DIRSIZ(&dir);
dir.d_off = ds->this_off;
dirent_terminate(&dir);
uiodir.dirent = &dir;
error = udf_uiodir(&uiodir, dir.d_reclen, uio,
ds->this_off);

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@ -1428,7 +1428,6 @@ mqfs_readdir(struct vop_readdir_args *ap)
entry.d_fileno = pn->mn_fileno;
for (i = 0; i < MQFS_NAMELEN - 1 && pn->mn_name[i] != '\0'; ++i)
entry.d_name[i] = pn->mn_name[i];
entry.d_name[i] = 0;
entry.d_namlen = i;
switch (pn->mn_type) {
case mqfstype_root:
@ -1447,6 +1446,7 @@ mqfs_readdir(struct vop_readdir_args *ap)
panic("%s has unexpected node type: %d", pn->mn_name,
pn->mn_type);
}
dirent_terminate(&entry);
if (entry.d_reclen > uio->uio_resid)
break;
if (offset >= uio->uio_offset) {

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@ -43,6 +43,7 @@ __FBSDID("$FreeBSD$");
#include "opt_inet6.h"
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/dirent.h>
#include <sys/jail.h>
#include <sys/kernel.h>
@ -55,7 +56,6 @@ __FBSDID("$FreeBSD$");
#include <sys/refcount.h>
#include <sys/signalvar.h>
#include <sys/socket.h>
#include <sys/systm.h>
#include <sys/vnode.h>
#include <netinet/in.h>

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@ -126,6 +126,19 @@ struct freebsd11_dirent {
#ifdef _KERNEL
#define GENERIC_DIRSIZ(dp) _GENERIC_DIRSIZ(dp)
/*
* Ensure that padding bytes are zeroed and that the name is NUL-terminated.
*/
static inline void
dirent_terminate(struct dirent *dp)
{
dp->d_pad0 = 0;
dp->d_pad1 = 0;
memset(dp->d_name + dp->d_namlen, 0,
dp->d_reclen - (__offsetof(struct dirent, d_name) + dp->d_namlen));
}
#endif
#endif /* !_SYS_DIRENT_H_ */

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@ -2217,9 +2217,9 @@ ufs_readdir(ap)
dstdp.d_fileno = dp->d_ino;
dstdp.d_reclen = GENERIC_DIRSIZ(&dstdp);
bcopy(dp->d_name, dstdp.d_name, dstdp.d_namlen);
dstdp.d_name[dstdp.d_namlen] = '\0';
/* NOTE: d_off is the offset of the *next* entry. */
dstdp.d_off = offset + dp->d_reclen;
dirent_terminate(&dstdp);
if (dstdp.d_reclen > uio->uio_resid) {
if (uio->uio_resid == startresid)
error = EINVAL;