diff options
| -rw-r--r-- | fs/nfs/nfs4proc.c | 31 | ||||
| -rw-r--r-- | fs/nfs/nfs4xdr.c | 14 | ||||
| -rw-r--r-- | include/linux/nfs_xdr.h | 2 |
3 files changed, 18 insertions, 29 deletions
diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c index 6b94f2d52532..1e50326d00dd 100644 --- a/fs/nfs/nfs4proc.c +++ b/fs/nfs/nfs4proc.c @@ -3739,7 +3739,7 @@ static void nfs4_write_cached_acl(struct inode *inode, struct page **pages, size struct nfs4_cached_acl *acl; size_t buflen = sizeof(*acl) + acl_len; - if (pages && buflen <= PAGE_SIZE) { + if (buflen <= PAGE_SIZE) { acl = kmalloc(buflen, GFP_KERNEL); if (acl == NULL) goto out; @@ -3784,7 +3784,6 @@ static ssize_t __nfs4_get_acl_uncached(struct inode *inode, void *buf, size_t bu }; unsigned int npages = DIV_ROUND_UP(buflen, PAGE_SIZE); int ret = -ENOMEM, i; - size_t acl_len = 0; /* As long as we're doing a round trip to the server anyway, * let's be prepared for a page of acl data. */ @@ -3807,11 +3806,6 @@ static ssize_t __nfs4_get_acl_uncached(struct inode *inode, void *buf, size_t bu args.acl_len = npages * PAGE_SIZE; args.acl_pgbase = 0; - /* Let decode_getfacl know not to fail if the ACL data is larger than - * the page we send as a guess */ - if (buf == NULL) - res.acl_flags |= NFS4_ACL_LEN_REQUEST; - dprintk("%s buf %p buflen %zu npages %d args.acl_len %zu\n", __func__, buf, buflen, npages, args.acl_len); ret = nfs4_call_sync(NFS_SERVER(inode)->client, NFS_SERVER(inode), @@ -3819,20 +3813,19 @@ static ssize_t __nfs4_get_acl_uncached(struct inode *inode, void *buf, size_t bu if (ret) goto out_free; - acl_len = res.acl_len; - if (acl_len > args.acl_len) - nfs4_write_cached_acl(inode, NULL, 0, acl_len); - else - nfs4_write_cached_acl(inode, pages, res.acl_data_offset, - acl_len); - if (buf) { + /* Handle the case where the passed-in buffer is too short */ + if (res.acl_flags & NFS4_ACL_TRUNC) { + /* Did the user only issue a request for the acl length? */ + if (buf == NULL) + goto out_ok; ret = -ERANGE; - if (acl_len > buflen) - goto out_free; - _copy_from_pages(buf, pages, res.acl_data_offset, - acl_len); + goto out_free; } - ret = acl_len; + nfs4_write_cached_acl(inode, pages, res.acl_data_offset, res.acl_len); + if (buf) + _copy_from_pages(buf, pages, res.acl_data_offset, res.acl_len); +out_ok: + ret = res.acl_len; out_free: for (i = 0; i < npages; i++) if (pages[i]) diff --git a/fs/nfs/nfs4xdr.c b/fs/nfs/nfs4xdr.c index 1bfbd67c556d..541e796e6db5 100644 --- a/fs/nfs/nfs4xdr.c +++ b/fs/nfs/nfs4xdr.c @@ -5072,18 +5072,14 @@ static int decode_getacl(struct xdr_stream *xdr, struct rpc_rqst *req, * are stored with the acl data to handle the problem of * variable length bitmaps.*/ res->acl_data_offset = xdr_stream_pos(xdr) - pg_offset; - - /* We ignore &savep and don't do consistency checks on - * the attr length. Let userspace figure it out.... */ res->acl_len = attrlen; - if (attrlen > (xdr->nwords << 2)) { - if (res->acl_flags & NFS4_ACL_LEN_REQUEST) { - /* getxattr interface called with a NULL buf */ - goto out; - } + + /* Check for receive buffer overflow */ + if (res->acl_len > (xdr->nwords << 2) || + res->acl_len + res->acl_data_offset > xdr->buf->page_len) { + res->acl_flags |= NFS4_ACL_TRUNC; dprintk("NFS: acl reply: attrlen %u > page_len %u\n", attrlen, xdr->nwords << 2); - return -EINVAL; } } else status = -EOPNOTSUPP; diff --git a/include/linux/nfs_xdr.h b/include/linux/nfs_xdr.h index ac7c8ae254f2..be9cf3c7e79e 100644 --- a/include/linux/nfs_xdr.h +++ b/include/linux/nfs_xdr.h @@ -652,7 +652,7 @@ struct nfs_getaclargs { }; /* getxattr ACL interface flags */ -#define NFS4_ACL_LEN_REQUEST 0x0001 /* zero length getxattr buffer */ +#define NFS4_ACL_TRUNC 0x0001 /* ACL was truncated */ struct nfs_getaclres { size_t acl_len; size_t acl_data_offset; |