diff options
author | Hugh Dickins <hughd@google.com> | 2012-10-07 20:32:51 -0700 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2012-10-21 09:32:39 -0700 |
commit | b080b7e727de8abc0c883de3d6a85a7ac3da31a5 (patch) | |
tree | 7d256c3ce23966ffe167f81b47b289c7c7adf51e /fs | |
parent | 5224f4e0e077c6c6336dc9640c81ea9799e620a6 (diff) |
tmpfs,ceph,gfs2,isofs,reiserfs,xfs: fix fh_len checking
commit 35c2a7f4908d404c9124c2efc6ada4640ca4d5d5 upstream.
Fuzzing with trinity oopsed on the 1st instruction of shmem_fh_to_dentry(),
u64 inum = fid->raw[2];
which is unhelpfully reported as at the end of shmem_alloc_inode():
BUG: unable to handle kernel paging request at ffff880061cd3000
IP: [<ffffffff812190d0>] shmem_alloc_inode+0x40/0x40
Oops: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC
Call Trace:
[<ffffffff81488649>] ? exportfs_decode_fh+0x79/0x2d0
[<ffffffff812d77c3>] do_handle_open+0x163/0x2c0
[<ffffffff812d792c>] sys_open_by_handle_at+0xc/0x10
[<ffffffff83a5f3f8>] tracesys+0xe1/0xe6
Right, tmpfs is being stupid to access fid->raw[2] before validating that
fh_len includes it: the buffer kmalloc'ed by do_sys_name_to_handle() may
fall at the end of a page, and the next page not be present.
But some other filesystems (ceph, gfs2, isofs, reiserfs, xfs) are being
careless about fh_len too, in fh_to_dentry() and/or fh_to_parent(), and
could oops in the same way: add the missing fh_len checks to those.
Reported-by: Sasha Levin <levinsasha928@gmail.com>
Signed-off-by: Hugh Dickins <hughd@google.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Sage Weil <sage@inktank.com>
Cc: Steven Whitehouse <swhiteho@redhat.com>
Cc: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'fs')
-rw-r--r-- | fs/ceph/export.c | 18 | ||||
-rw-r--r-- | fs/gfs2/export.c | 4 | ||||
-rw-r--r-- | fs/isofs/export.c | 2 | ||||
-rw-r--r-- | fs/reiserfs/inode.c | 6 | ||||
-rw-r--r-- | fs/xfs/xfs_export.c | 3 |
5 files changed, 27 insertions, 6 deletions
diff --git a/fs/ceph/export.c b/fs/ceph/export.c index 8e1b60e557b..02ce90972d8 100644 --- a/fs/ceph/export.c +++ b/fs/ceph/export.c @@ -99,7 +99,7 @@ static int ceph_encode_fh(struct inode *inode, u32 *rawfh, int *max_len, * FIXME: we should try harder by querying the mds for the ino. */ static struct dentry *__fh_to_dentry(struct super_block *sb, - struct ceph_nfs_fh *fh) + struct ceph_nfs_fh *fh, int fh_len) { struct ceph_mds_client *mdsc = ceph_sb_to_client(sb)->mdsc; struct inode *inode; @@ -107,6 +107,9 @@ static struct dentry *__fh_to_dentry(struct super_block *sb, struct ceph_vino vino; int err; + if (fh_len < sizeof(*fh) / 4) + return ERR_PTR(-ESTALE); + dout("__fh_to_dentry %llx\n", fh->ino); vino.ino = fh->ino; vino.snap = CEPH_NOSNAP; @@ -150,7 +153,7 @@ static struct dentry *__fh_to_dentry(struct super_block *sb, * convert connectable fh to dentry */ static struct dentry *__cfh_to_dentry(struct super_block *sb, - struct ceph_nfs_confh *cfh) + struct ceph_nfs_confh *cfh, int fh_len) { struct ceph_mds_client *mdsc = ceph_sb_to_client(sb)->mdsc; struct inode *inode; @@ -158,6 +161,9 @@ static struct dentry *__cfh_to_dentry(struct super_block *sb, struct ceph_vino vino; int err; + if (fh_len < sizeof(*cfh) / 4) + return ERR_PTR(-ESTALE); + dout("__cfh_to_dentry %llx (%llx/%x)\n", cfh->ino, cfh->parent_ino, cfh->parent_name_hash); @@ -207,9 +213,11 @@ static struct dentry *ceph_fh_to_dentry(struct super_block *sb, struct fid *fid, int fh_len, int fh_type) { if (fh_type == 1) - return __fh_to_dentry(sb, (struct ceph_nfs_fh *)fid->raw); + return __fh_to_dentry(sb, (struct ceph_nfs_fh *)fid->raw, + fh_len); else - return __cfh_to_dentry(sb, (struct ceph_nfs_confh *)fid->raw); + return __cfh_to_dentry(sb, (struct ceph_nfs_confh *)fid->raw, + fh_len); } /* @@ -230,6 +238,8 @@ static struct dentry *ceph_fh_to_parent(struct super_block *sb, if (fh_type == 1) return ERR_PTR(-ESTALE); + if (fh_len < sizeof(*cfh) / 4) + return ERR_PTR(-ESTALE); pr_debug("fh_to_parent %llx/%d\n", cfh->parent_ino, cfh->parent_name_hash); diff --git a/fs/gfs2/export.c b/fs/gfs2/export.c index e8ed6d4a618..4767774a5f3 100644 --- a/fs/gfs2/export.c +++ b/fs/gfs2/export.c @@ -161,6 +161,8 @@ static struct dentry *gfs2_fh_to_dentry(struct super_block *sb, struct fid *fid, case GFS2_SMALL_FH_SIZE: case GFS2_LARGE_FH_SIZE: case GFS2_OLD_FH_SIZE: + if (fh_len < GFS2_SMALL_FH_SIZE) + return NULL; this.no_formal_ino = ((u64)be32_to_cpu(fh[0])) << 32; this.no_formal_ino |= be32_to_cpu(fh[1]); this.no_addr = ((u64)be32_to_cpu(fh[2])) << 32; @@ -180,6 +182,8 @@ static struct dentry *gfs2_fh_to_parent(struct super_block *sb, struct fid *fid, switch (fh_type) { case GFS2_LARGE_FH_SIZE: case GFS2_OLD_FH_SIZE: + if (fh_len < GFS2_LARGE_FH_SIZE) + return NULL; parent.no_formal_ino = ((u64)be32_to_cpu(fh[4])) << 32; parent.no_formal_ino |= be32_to_cpu(fh[5]); parent.no_addr = ((u64)be32_to_cpu(fh[6])) << 32; diff --git a/fs/isofs/export.c b/fs/isofs/export.c index 1d3804492aa..2b4f2358ead 100644 --- a/fs/isofs/export.c +++ b/fs/isofs/export.c @@ -175,7 +175,7 @@ static struct dentry *isofs_fh_to_parent(struct super_block *sb, { struct isofs_fid *ifid = (struct isofs_fid *)fid; - if (fh_type != 2) + if (fh_len < 2 || fh_type != 2) return NULL; return isofs_export_iget(sb, diff --git a/fs/reiserfs/inode.c b/fs/reiserfs/inode.c index 855da58db14..63ce6be94c4 100644 --- a/fs/reiserfs/inode.c +++ b/fs/reiserfs/inode.c @@ -1573,8 +1573,10 @@ struct dentry *reiserfs_fh_to_dentry(struct super_block *sb, struct fid *fid, reiserfs_warning(sb, "reiserfs-13077", "nfsd/reiserfs, fhtype=%d, len=%d - odd", fh_type, fh_len); - fh_type = 5; + fh_type = fh_len; } + if (fh_len < 2) + return NULL; return reiserfs_get_dentry(sb, fid->raw[0], fid->raw[1], (fh_type == 3 || fh_type >= 5) ? fid->raw[2] : 0); @@ -1583,6 +1585,8 @@ struct dentry *reiserfs_fh_to_dentry(struct super_block *sb, struct fid *fid, struct dentry *reiserfs_fh_to_parent(struct super_block *sb, struct fid *fid, int fh_len, int fh_type) { + if (fh_type > fh_len) + fh_type = fh_len; if (fh_type < 4) return NULL; diff --git a/fs/xfs/xfs_export.c b/fs/xfs/xfs_export.c index 42679223a0f..8c6d1d70278 100644 --- a/fs/xfs/xfs_export.c +++ b/fs/xfs/xfs_export.c @@ -189,6 +189,9 @@ xfs_fs_fh_to_parent(struct super_block *sb, struct fid *fid, struct xfs_fid64 *fid64 = (struct xfs_fid64 *)fid; struct inode *inode = NULL; + if (fh_len < xfs_fileid_length(fileid_type)) + return NULL; + switch (fileid_type) { case FILEID_INO32_GEN_PARENT: inode = xfs_nfs_get_inode(sb, fid->i32.parent_ino, |