From: Trond Myklebust Subject: NFSv3: Fix posix ACL code References: 465854 Patch-mainline: 2.6.29-rc7 Upstream commit ae46141ff08f1965b17c531b571953c39ce8b9e2. Fix a memory leak due to allocation in the XDR layer. In cases where the RPC call needs to be retransmitted, we end up allocating new pages without clearing the old ones. Fix this by moving the allocation into nfs3_proc_setacls(). Also fix an issue discovered by Kevin Rudd, whereby the amount of memory reserved for the acls in the xdr_buf->head was miscalculated, and causing corruption. Signed-off-by: Trond Myklebust Signed-off-by: Suresh Jayaraman --- fs/nfs/nfs3acl.c | 27 +++++++++++++++++++++------ fs/nfs/nfs3xdr.c | 34 +++++++++++++--------------------- include/linux/nfs_xdr.h | 2 ++ include/linux/nfsacl.h | 3 +++ 4 files changed, 39 insertions(+), 27 deletions(-) Index: linux-2.6.27-SLE11_BRANCH/fs/nfs/nfs3acl.c =================================================================== --- linux-2.6.27-SLE11_BRANCH.orig/fs/nfs/nfs3acl.c +++ linux-2.6.27-SLE11_BRANCH/fs/nfs/nfs3acl.c @@ -291,7 +291,7 @@ static int nfs3_proc_setacls(struct inod { struct nfs_server *server = NFS_SERVER(inode); struct nfs_fattr fattr; - struct page *pages[NFSACL_MAXPAGES] = { }; + struct page *pages[NFSACL_MAXPAGES]; struct nfs3_setaclargs args = { .inode = inode, .mask = NFS_ACL, @@ -302,7 +302,7 @@ static int nfs3_proc_setacls(struct inod .rpc_argp = &args, .rpc_resp = &fattr, }; - int status, count; + int status; status = -EOPNOTSUPP; if (!nfs_server_capable(inode, NFS_CAP_ACLS)) @@ -318,6 +318,20 @@ static int nfs3_proc_setacls(struct inod if (S_ISDIR(inode->i_mode)) { args.mask |= NFS_DFACL; args.acl_default = dfacl; + args.len = nfsacl_size(acl, dfacl); + } else + args.len = nfsacl_size(acl, NULL); + + if (args.len > NFS_ACL_INLINE_BUFSIZE) { + unsigned int npages = 1 + ((args.len - 1) >> PAGE_SHIFT); + + status = -ENOMEM; + do { + args.pages[args.npages] = alloc_page(GFP_KERNEL); + if (args.pages[args.npages] == NULL) + goto out_freepages; + args.npages++; + } while (args.npages < npages); } dprintk("NFS call setacl\n"); @@ -327,10 +341,6 @@ static int nfs3_proc_setacls(struct inod nfs_zap_acl_cache(inode); dprintk("NFS reply setacl: %d\n", status); - /* pages may have been allocated at the xdr layer. */ - for (count = 0; count < NFSACL_MAXPAGES && args.pages[count]; count++) - __free_page(args.pages[count]); - switch (status) { case 0: status = nfs_refresh_inode(inode, &fattr); @@ -344,6 +354,11 @@ static int nfs3_proc_setacls(struct inod case -ENOTSUPP: status = -EOPNOTSUPP; } +out_freepages: + while (args.npages != 0) { + args.npages--; + __free_page(args.pages[args.npages]); + } out: return status; } Index: linux-2.6.27-SLE11_BRANCH/fs/nfs/nfs3xdr.c =================================================================== --- linux-2.6.27-SLE11_BRANCH.orig/fs/nfs/nfs3xdr.c +++ linux-2.6.27-SLE11_BRANCH/fs/nfs/nfs3xdr.c @@ -82,8 +82,10 @@ #define NFS3_commitres_sz (1+NFS3_wcc_data_sz+2) #define ACL3_getaclargs_sz (NFS3_fh_sz+1) -#define ACL3_setaclargs_sz (NFS3_fh_sz+1+2*(2+5*3)) -#define ACL3_getaclres_sz (1+NFS3_post_op_attr_sz+1+2*(2+5*3)) +#define ACL3_setaclargs_sz (NFS3_fh_sz+1+ \ + XDR_QUADLEN(NFS_ACL_INLINE_BUFSIZE)) +#define ACL3_getaclres_sz (1+NFS3_post_op_attr_sz+1+ \ + XDR_QUADLEN(NFS_ACL_INLINE_BUFSIZE)) #define ACL3_setaclres_sz (1+NFS3_post_op_attr_sz) /* @@ -703,28 +705,18 @@ nfs3_xdr_setaclargs(struct rpc_rqst *req struct nfs3_setaclargs *args) { struct xdr_buf *buf = &req->rq_snd_buf; - unsigned int base, len_in_head, len = nfsacl_size( - (args->mask & NFS_ACL) ? args->acl_access : NULL, - (args->mask & NFS_DFACL) ? args->acl_default : NULL); - int count, err; + unsigned int base; + int err; p = xdr_encode_fhandle(p, NFS_FH(args->inode)); *p++ = htonl(args->mask); - base = (char *)p - (char *)buf->head->iov_base; - /* put as much of the acls into head as possible. */ - len_in_head = min_t(unsigned int, buf->head->iov_len - base, len); - len -= len_in_head; - req->rq_slen = xdr_adjust_iovec(req->rq_svec, p + (len_in_head >> 2)); - - for (count = 0; (count << PAGE_SHIFT) < len; count++) { - args->pages[count] = alloc_page(GFP_KERNEL); - if (!args->pages[count]) { - while (count) - __free_page(args->pages[--count]); - return -ENOMEM; - } - } - xdr_encode_pages(buf, args->pages, 0, len); + req->rq_slen = xdr_adjust_iovec(req->rq_svec, p); + base = req->rq_slen; + + if (args->npages != 0) + xdr_encode_pages(buf, args->pages, 0, args->len); + else + req->rq_slen += args->len; err = nfsacl_encode(buf, base, args->inode, (args->mask & NFS_ACL) ? Index: linux-2.6.27-SLE11_BRANCH/include/linux/nfs_xdr.h =================================================================== --- linux-2.6.27-SLE11_BRANCH.orig/include/linux/nfs_xdr.h +++ linux-2.6.27-SLE11_BRANCH/include/linux/nfs_xdr.h @@ -404,6 +404,8 @@ struct nfs3_setaclargs { int mask; struct posix_acl * acl_access; struct posix_acl * acl_default; + size_t len; + unsigned int npages; struct page ** pages; }; Index: linux-2.6.27-SLE11_BRANCH/include/linux/nfsacl.h =================================================================== --- linux-2.6.27-SLE11_BRANCH.orig/include/linux/nfsacl.h +++ linux-2.6.27-SLE11_BRANCH/include/linux/nfsacl.h @@ -37,6 +37,9 @@ #define NFSACL_MAXPAGES ((2*(8+12*NFS_ACL_MAX_ENTRIES) + PAGE_SIZE-1) \ >> PAGE_SHIFT) +#define NFS_ACL_MAX_ENTRIES_INLINE (5) +#define NFS_ACL_INLINE_BUFSIZE ((2*(2+3*NFS_ACL_MAX_ENTRIES_INLINE)) << 2) + static inline unsigned int nfsacl_size(struct posix_acl *acl_access, struct posix_acl *acl_default) {