3.2-stable review patch. If anyone has any objections, please let me know.
------------------ From: Sachin Prabhu <[email protected]> commit 5794d21ef4639f0e33440927bb903f9598c21e92 upstream. When attempting to cache ACLs returned from the server, if the bitmap size + the ACL size is greater than a PAGE_SIZE but the ACL size itself is smaller than a PAGE_SIZE, we can read past the buffer page boundary. Signed-off-by: Sachin Prabhu <[email protected]> Reported-by: Jian Li <[email protected]> Signed-off-by: Trond Myklebust <[email protected]> Signed-off-by: Ben Hutchings <[email protected]> --- fs/nfs/nfs4proc.c | 12 +++++------- fs/nfs/nfs4xdr.c | 2 +- 2 files changed, 6 insertions(+), 8 deletions(-) diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c index f5f125f..2ce0698 100644 --- a/fs/nfs/nfs4proc.c +++ b/fs/nfs/nfs4proc.c @@ -3628,16 +3628,16 @@ out: return ret; } -static void nfs4_write_cached_acl(struct inode *inode, const char *buf, size_t acl_len) +static void nfs4_write_cached_acl(struct inode *inode, struct page **pages, size_t pgbase, size_t acl_len) { struct nfs4_cached_acl *acl; - if (buf && acl_len <= PAGE_SIZE) { + if (pages && acl_len <= PAGE_SIZE) { acl = kmalloc(sizeof(*acl) + acl_len, GFP_KERNEL); if (acl == NULL) goto out; acl->cached = 1; - memcpy(acl->data, buf, acl_len); + _copy_from_pages(acl->data, pages, pgbase, acl_len); } else { acl = kmalloc(sizeof(*acl), GFP_KERNEL); if (acl == NULL) @@ -3670,7 +3670,6 @@ static ssize_t __nfs4_get_acl_uncached(struct inode *inode, void *buf, size_t bu struct nfs_getaclres res = { .acl_len = buflen, }; - void *resp_buf; struct rpc_message msg = { .rpc_proc = &nfs4_procedures[NFSPROC4_CLNT_GETACL], .rpc_argp = &args, @@ -3705,7 +3704,6 @@ static ssize_t __nfs4_get_acl_uncached(struct inode *inode, void *buf, size_t bu * the page we send as a guess */ if (buf == NULL) res.acl_flags |= NFS4_ACL_LEN_REQUEST; - resp_buf = page_address(pages[0]); dprintk("%s buf %p buflen %zu npages %d args.acl_len %zu\n", __func__, buf, buflen, npages, args.acl_len); @@ -3716,9 +3714,9 @@ static ssize_t __nfs4_get_acl_uncached(struct inode *inode, void *buf, size_t bu acl_len = res.acl_len - res.acl_data_offset; if (acl_len > args.acl_len) - nfs4_write_cached_acl(inode, NULL, acl_len); + nfs4_write_cached_acl(inode, NULL, 0, acl_len); else - nfs4_write_cached_acl(inode, resp_buf + res.acl_data_offset, + nfs4_write_cached_acl(inode, pages, res.acl_data_offset, acl_len); if (buf) { ret = -ERANGE; diff --git a/fs/nfs/nfs4xdr.c b/fs/nfs/nfs4xdr.c index 9312dd7..203c096 100644 --- a/fs/nfs/nfs4xdr.c +++ b/fs/nfs/nfs4xdr.c @@ -4940,7 +4940,7 @@ static int decode_getacl(struct xdr_stream *xdr, struct rpc_rqst *req, res->acl_len = attrlen; goto out; } - dprintk("NFS: acl reply: attrlen %zu > page_len %u\n", + dprintk("NFS: acl reply: attrlen %u > page_len %zu\n", attrlen, page_len); return -EINVAL; } -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
