smb: client: improve compound padding in encryption

After commit f7f291e14dde ("cifs: fix oops during encryption"), the
encryption layer can handle vmalloc'd buffers as well as kmalloc'd
buffers, so there is no need to inefficiently squash request iovs
into a single one to handle padding in compound requests.

Cc: David Howells <dhowells@redhat.com>
Signed-off-by: Paulo Alcantara (Red Hat) <pc@manguebit.com>
Signed-off-by: Steve French <stfrench@microsoft.com>

diff --git a/fs/smb/client/cifsglob.h b/fs/smb/client/cifsglob.h
index 63d194ebbd7d9b7edfa8b74fc2b15b3afa2655c7..fc33dfe7e925453e6366144934bffa30af5bbe58 100644 (file)
--- a/fs/smb/client/cifsglob.h
+++ b/fs/smb/client/cifsglob.h
@@ -2230,7 +2230,7 @@ static inline int cifs_get_num_sgs(const struct smb_rqst *rqst,
                        struct kvec *iov = &rqst[i].rq_iov[j];
 
                        addr = (unsigned long)iov->iov_base + skip;
-                       if (unlikely(is_vmalloc_addr((void *)addr))) {
+                       if (is_vmalloc_or_module_addr((void *)addr)) {
                                len = iov->iov_len - skip;
                                nents += DIV_ROUND_UP(offset_in_page(addr) + len,
                                                      PAGE_SIZE);
@@ -2257,7 +2257,7 @@ static inline void cifs_sg_set_buf(struct sg_table *sgtable,
        unsigned int off = offset_in_page(addr);
 
        addr &= PAGE_MASK;
-       if (unlikely(is_vmalloc_addr((void *)addr))) {
+       if (is_vmalloc_or_module_addr((void *)addr)) {
                do {
                        unsigned int len = min_t(unsigned int, buflen, PAGE_SIZE - off);
 

diff --git a/fs/smb/client/smb2ops.c b/fs/smb/client/smb2ops.c
index 7571fefeb83aa19d32a44e66b6f9ffe4e526c4c6..fa96ebed831082d029e85db6373304a1a867a21e 100644 (file)
--- a/fs/smb/client/smb2ops.c
+++ b/fs/smb/client/smb2ops.c
@@ -2606,7 +2606,7 @@ smb2_set_next_command(struct cifs_tcon *tcon, struct smb_rqst *rqst)
        struct cifs_ses *ses = tcon->ses;
        struct TCP_Server_Info *server = ses->server;
        unsigned long len = smb_rqst_len(server, rqst);
-       int i, num_padding;
+       int num_padding;
 
        shdr = (struct smb2_hdr *)(rqst->rq_iov[0].iov_base);
        if (shdr == NULL) {
@@ -2615,44 +2615,13 @@ smb2_set_next_command(struct cifs_tcon *tcon, struct smb_rqst *rqst)
        }
 
        /* SMB headers in a compound are 8 byte aligned. */
-
-       /* No padding needed */
-       if (!(len & 7))
-               goto finished;
-
-       num_padding = 8 - (len & 7);
-       if (!smb3_encryption_required(tcon)) {
-               /*
-                * If we do not have encryption then we can just add an extra
-                * iov for the padding.
-                */
+       if (!IS_ALIGNED(len, 8)) {
+               num_padding = 8 - (len & 7);
                rqst->rq_iov[rqst->rq_nvec].iov_base = smb2_padding;
                rqst->rq_iov[rqst->rq_nvec].iov_len = num_padding;
                rqst->rq_nvec++;
                len += num_padding;
-       } else {
-               /*
-                * We can not add a small padding iov for the encryption case
-                * because the encryption framework can not handle the padding
-                * iovs.
-                * We have to flatten this into a single buffer and add
-                * the padding to it.
-                */
-               for (i = 1; i < rqst->rq_nvec; i++) {
-                       memcpy(rqst->rq_iov[0].iov_base +
-                              rqst->rq_iov[0].iov_len,
-                              rqst->rq_iov[i].iov_base,
-                              rqst->rq_iov[i].iov_len);
-                       rqst->rq_iov[0].iov_len += rqst->rq_iov[i].iov_len;
-               }
-               memset(rqst->rq_iov[0].iov_base + rqst->rq_iov[0].iov_len,
-                      0, num_padding);
-               rqst->rq_iov[0].iov_len += num_padding;
-               len += num_padding;
-               rqst->rq_nvec = 1;
        }
-
- finished:
        shdr->NextCommand = cpu_to_le32(len);
 }
 

diff --git a/fs/smb/client/transport.c b/fs/smb/client/transport.c
index 91812150186c01bc1545c9ea7ecd88413ebd5b88..0dc80959ce48852f58f7cd9204c151cfdf246591 100644 (file)
--- a/fs/smb/client/transport.c
+++ b/fs/smb/client/transport.c
@@ -418,19 +418,16 @@ out:
        return rc;
 }
 
-struct send_req_vars {
-       struct smb2_transform_hdr tr_hdr;
-       struct smb_rqst rqst[MAX_COMPOUND];
-       struct kvec iov;
-};
-
 static int
 smb_send_rqst(struct TCP_Server_Info *server, int num_rqst,
              struct smb_rqst *rqst, int flags)
 {
-       struct send_req_vars *vars;
-       struct smb_rqst *cur_rqst;
-       struct kvec *iov;
+       struct smb2_transform_hdr tr_hdr;
+       struct smb_rqst new_rqst[MAX_COMPOUND] = {};
+       struct kvec iov = {
+               .iov_base = &tr_hdr,
+               .iov_len = sizeof(tr_hdr),
+       };
        int rc;
 
        if (flags & CIFS_COMPRESS_REQ)
@@ -447,26 +444,15 @@ smb_send_rqst(struct TCP_Server_Info *server, int num_rqst,
                return -EIO;
        }
 
-       vars = kzalloc(sizeof(*vars), GFP_NOFS);
-       if (!vars)
-               return -ENOMEM;
-       cur_rqst = vars->rqst;
-       iov = &vars->iov;
-
-       iov->iov_base = &vars->tr_hdr;
-       iov->iov_len = sizeof(vars->tr_hdr);
-       cur_rqst[0].rq_iov = iov;
-       cur_rqst[0].rq_nvec = 1;
+       new_rqst[0].rq_iov = &iov;
+       new_rqst[0].rq_nvec = 1;
 
        rc = server->ops->init_transform_rq(server, num_rqst + 1,
-                                           &cur_rqst[0], rqst);
-       if (rc)
-               goto out;
-
-       rc = __smb_send_rqst(server, num_rqst + 1, &cur_rqst[0]);
-       smb3_free_compound_rqst(num_rqst, &cur_rqst[1]);
-out:
-       kfree(vars);
+                                           new_rqst, rqst);
+       if (!rc) {
+               rc = __smb_send_rqst(server, num_rqst + 1, new_rqst);
+               smb3_free_compound_rqst(num_rqst, &new_rqst[1]);
+       }
        return rc;
 }