LU-3587 changelogs: Correct KUC code max changelog msg size

The kernel to userspace communication routines (KUC) allocate
and limit the maximum cs_buf size to CR_MAXSIZE.  However this
fails to account for the fact that the buffer is assumed to begin
with a struct kuc_hdr.  To allocate and account for that space,
we introduce a new define, KUC_CHANGELOG_MSG_MAXSIZE.

Change-Id: I623746126dd64c8016366ee5fdce094129e4103e
Signed-off-by: Christopher J. Morrone <morrone2@llnl.gov>
Reviewed-on: http://review.whamcloud.com/7406
Tested-by: Hudson
Tested-by: Maloo <whamcloud.maloo@gmail.com>
Reviewed-by: Andreas Dilger <andreas.dilger@intel.com>
Reviewed-by: jacques-Charles Lafoucriere <jacques-charles.lafoucriere@cea.fr>
Reviewed-by: Oleg Drokin <oleg.drokin@intel.com>

diff --git a/libcfs/include/libcfs/libcfs_kernelcomm.h b/libcfs/include/libcfs/libcfs_kernelcomm.h
index acf4779..c630ba3 100644 (file)
--- a/libcfs/include/libcfs/libcfs_kernelcomm.h
+++ b/libcfs/include/libcfs/libcfs_kernelcomm.h
@@ -61,6 +61,8 @@ struct kuc_hdr {
         __u16 kuc_msglen;     /* Including header */
 } __attribute__((aligned(sizeof(__u64))));
 
         __u16 kuc_msglen;     /* Including header */
 } __attribute__((aligned(sizeof(__u64))));
 

+#define KUC_CHANGELOG_MSG_MAXSIZE (sizeof(struct kuc_hdr)+CR_MAXSIZE)
+

 #define KUC_MAGIC  0x191C /*Lustre9etLinC */
 #define KUC_FL_BLOCK 0x01   /* Wait for send */
 
 #define KUC_MAGIC  0x191C /*Lustre9etLinC */
 #define KUC_FL_BLOCK 0x01   /* Wait for send */
 

diff --git a/lustre/mdc/mdc_request.c b/lustre/mdc/mdc_request.c
index b435b07..24b50c7 100644 (file)
--- a/lustre/mdc/mdc_request.c
+++ b/lustre/mdc/mdc_request.c
@@ -1531,16 +1531,16 @@ out:
 
 static struct kuc_hdr *changelog_kuc_hdr(char *buf, int len, int flags)
 {
 
 static struct kuc_hdr *changelog_kuc_hdr(char *buf, int len, int flags)
 {

-        struct kuc_hdr *lh = (struct kuc_hdr *)buf;
+       struct kuc_hdr *lh = (struct kuc_hdr *)buf;

 
 

-        LASSERT(len <= CR_MAXSIZE);
+       LASSERT(len <= KUC_CHANGELOG_MSG_MAXSIZE);

 
 

-        lh->kuc_magic = KUC_MAGIC;
-        lh->kuc_transport = KUC_TRANSPORT_CHANGELOG;
-        lh->kuc_flags = flags;
-        lh->kuc_msgtype = CL_RECORD;
-        lh->kuc_msglen = len;
-        return lh;
+       lh->kuc_magic = KUC_MAGIC;
+       lh->kuc_transport = KUC_TRANSPORT_CHANGELOG;
+       lh->kuc_flags = flags;
+       lh->kuc_msgtype = CL_RECORD;
+       lh->kuc_msglen = len;
+       return lh;

 }
 
 #define D_CHANGELOG 0
 }
 
 #define D_CHANGELOG 0


@@ -1598,18 +1598,18 @@ static int changelog_kkuc_cb(const struct lu_env *env, struct llog_handle *llh,
 
 static int mdc_changelog_send_thread(void *csdata)
 {
 
 static int mdc_changelog_send_thread(void *csdata)
 {

-        struct changelog_show *cs = csdata;
-        struct llog_ctxt *ctxt = NULL;
-        struct llog_handle *llh = NULL;
-        struct kuc_hdr *kuch;
-        int rc;
+       struct changelog_show *cs = csdata;
+       struct llog_ctxt *ctxt = NULL;
+       struct llog_handle *llh = NULL;
+       struct kuc_hdr *kuch;
+       int rc;

 
 

-        CDEBUG(D_CHANGELOG, "changelog to fp=%p start "LPU64"\n",
-               cs->cs_fp, cs->cs_startrec);
+       CDEBUG(D_CHANGELOG, "changelog to fp=%p start "LPU64"\n",
+              cs->cs_fp, cs->cs_startrec);

 
 

-        OBD_ALLOC(cs->cs_buf, CR_MAXSIZE);
-        if (cs->cs_buf == NULL)
-                GOTO(out, rc = -ENOMEM);
+       OBD_ALLOC(cs->cs_buf, KUC_CHANGELOG_MSG_MAXSIZE);
+       if (cs->cs_buf == NULL)
+               GOTO(out, rc = -ENOMEM);

 
         /* Set up the remote catalog handle */
         ctxt = llog_get_context(cs->cs_obd, LLOG_CHANGELOG_REPL_CTXT);
 
         /* Set up the remote catalog handle */
         ctxt = llog_get_context(cs->cs_obd, LLOG_CHANGELOG_REPL_CTXT);


@@ -1644,7 +1644,7 @@ out:
         if (ctxt)
                 llog_ctxt_put(ctxt);
        if (cs->cs_buf)
         if (ctxt)
                 llog_ctxt_put(ctxt);
        if (cs->cs_buf)

-               OBD_FREE(cs->cs_buf, CR_MAXSIZE);
+               OBD_FREE(cs->cs_buf, KUC_CHANGELOG_MSG_MAXSIZE);

        OBD_FREE_PTR(cs);
        return rc;
 }
        OBD_FREE_PTR(cs);
        return rc;
 }

diff --git a/lustre/utils/liblustreapi.c b/lustre/utils/liblustreapi.c
index ed8ce97..015036d 100644 (file)
--- a/lustre/utils/liblustreapi.c
+++ b/lustre/utils/liblustreapi.c
@@ -3945,24 +3945,24 @@ static inline int changelog_extend_rec(struct changelog_ext_rec *ext)
  */
 int llapi_changelog_recv(void *priv, struct changelog_ext_rec **rech)
 {
  */
 int llapi_changelog_recv(void *priv, struct changelog_ext_rec **rech)
 {

-        struct changelog_private *cp = (struct changelog_private *)priv;
-        struct kuc_hdr *kuch;
-        int rc = 0;
+       struct changelog_private *cp = (struct changelog_private *)priv;
+       struct kuc_hdr *kuch;
+       int rc = 0;

 
 

-        if (!cp || (cp->magic != CHANGELOG_PRIV_MAGIC))
-                return -EINVAL;
-        if (rech == NULL)
-                return -EINVAL;
-        kuch = malloc(CR_MAXSIZE + sizeof(*kuch));
-        if (kuch == NULL)
-                return -ENOMEM;
+       if (!cp || (cp->magic != CHANGELOG_PRIV_MAGIC))
+               return -EINVAL;
+       if (rech == NULL)
+               return -EINVAL;
+       kuch = malloc(KUC_CHANGELOG_MSG_MAXSIZE);
+       if (kuch == NULL)
+               return -ENOMEM;

 
 repeat:
 
 repeat:

-        rc = libcfs_ukuc_msg_get(&cp->kuc, (char *)kuch,
-                                 CR_MAXSIZE + sizeof(*kuch),
-                                 KUC_TRANSPORT_CHANGELOG);
-        if (rc < 0)
-                goto out_free;
+       rc = libcfs_ukuc_msg_get(&cp->kuc, (char *)kuch,
+                                KUC_CHANGELOG_MSG_MAXSIZE,
+                                KUC_TRANSPORT_CHANGELOG);
+       if (rc < 0)
+               goto out_free;

 
         if ((kuch->kuc_transport != KUC_TRANSPORT_CHANGELOG) ||
             ((kuch->kuc_msgtype != CL_RECORD) &&
 
         if ((kuch->kuc_transport != KUC_TRANSPORT_CHANGELOG) ||
             ((kuch->kuc_msgtype != CL_RECORD) &&