multiple: fix bad type cast

When using inode_ctx_get() or inode_ctx_set(), a 'uint64_t *' is expected.
In many cases, the value to retrieve or store is a pointer, which will be
of smaller size in some architectures (for example 32-bits). In this case,
directly passing the address of the pointer casted to an 'uint64_t *' is
wrong and can cause memory corruption.

Backport of:
> Change-Id: Iae616da9dda528df6743fa2f65ae5cff5ad23258
> Signed-off-by: Xavi Hernandez <xhernandez@redhat.com>
> Fixes: bz#1785611

Change-Id: Iae616da9dda528df6743fa2f65ae5cff5ad23258
Signed-off-by: Xavi Hernandez <xhernandez@redhat.com>
Fixes: bz#1785323

2 files changed, 27 insertions, 11 deletions

diff --git a/xlators/storage/posix/src/posix-helpers.c b/xlators/storage/posix/src/posix-helpers.c
index d2beeed1f4a..0ee412875ef 100644
--- a/xlators/storage/posix/src/posix-helpers.c
+++ b/xlators/storage/posix/src/posix-helpers.c
@@ -2828,7 +2828,8 @@ __posix_inode_ctx_get(inode_t *inode, xlator_t *this)
     pthread_mutex_init(&ctx_p->write_atomic_lock, NULL);
     pthread_mutex_init(&ctx_p->pgfid_lock, NULL);
 
-    ret = __inode_ctx_set(inode, this, (uint64_t *)&ctx_p);
+    ctx_uint = (uint64_t)(uintptr_t)ctx_p;
+    ret = __inode_ctx_set(inode, this, &ctx_uint);
     if (ret < 0) {
         pthread_mutex_destroy(&ctx_p->xattrop_lock);
         pthread_mutex_destroy(&ctx_p->write_atomic_lock);
diff --git a/xlators/storage/posix/src/posix-metadata.c b/xlators/storage/posix/src/posix-metadata.c
index 9efaf999402..0b6f04f337f 100644
--- a/xlators/storage/posix/src/posix-metadata.c
+++ b/xlators/storage/posix/src/posix-metadata.c
@@ -243,6 +243,7 @@ int
 __posix_get_mdata_xattr(xlator_t *this, const char *real_path, int _fd,
                         inode_t *inode, struct iatt *stbuf)
 {
+    uint64_t ctx;
     posix_mdata_t *mdata = NULL;
     int ret = -1;
     int op_errno = 0;
@@ -250,7 +251,10 @@ __posix_get_mdata_xattr(xlator_t *this, const char *real_path, int _fd,
     /* Handle readdirp: inode might be null, time attributes should be served
      * from xattr not from backend's file attributes */
     if (inode) {
-        ret = __inode_ctx_get1(inode, this, (uint64_t *)&mdata);
+        ret = __inode_ctx_get1(inode, this, &ctx);
+        if (ret == 0) {
+            mdata = (posix_mdata_t *)(uintptr_t)ctx;
+        }
     } else {
         ret = -1;
     }
@@ -275,7 +279,8 @@ __posix_get_mdata_xattr(xlator_t *this, const char *real_path, int _fd,
              * down scenario
              */
             if (inode) {
-                __inode_ctx_set1(inode, this, (uint64_t *)&mdata);
+                ctx = (uint64_t)(uintptr_t)mdata;
+                __inode_ctx_set1(inode, this, &ctx);
             }
         } else {
             /* Failed to get mdata from disk, xattr missing.
@@ -357,6 +362,7 @@ posix_set_mdata_xattr_legacy_files(xlator_t *this, inode_t *inode,
                                    const char *realpath,
                                    struct mdata_iatt *mdata_iatt, int *op_errno)
 {
+    uint64_t ctx;
     posix_mdata_t *mdata = NULL;
     posix_mdata_t imdata = {
         0,
@@ -369,10 +375,11 @@ posix_set_mdata_xattr_legacy_files(xlator_t *this, inode_t *inode,
 
     LOCK(&inode->lock);
     {
-        ret = __inode_ctx_get1(inode, this, (uint64_t *)&mdata);
-        if (ret == 0 && mdata) {
+        ret = __inode_ctx_get1(inode, this, &ctx);
+        if (ret == 0 && ctx) {
+            mdata = (posix_mdata_t *)(uintptr_t)ctx;
             mdata_already_set = _gf_true;
-        } else if (ret == -1 || !mdata) {
+        } else {
             mdata = GF_CALLOC(1, sizeof(posix_mdata_t), gf_posix_mt_mdata_attr);
             if (!mdata) {
                 gf_msg(this->name, GF_LOG_ERROR, ENOMEM, P_MSG_NOMEM,
@@ -389,7 +396,8 @@ posix_set_mdata_xattr_legacy_files(xlator_t *this, inode_t *inode,
                 /* Got mdata from disk. This is a race, another client
                  * has healed the xattr during lookup. So set it in inode
                  * ctx */
-                __inode_ctx_set1(inode, this, (uint64_t *)&mdata);
+                ctx = (uint64_t)(uintptr_t)mdata;
+                __inode_ctx_set1(inode, this, &ctx);
                 mdata_already_set = _gf_true;
             } else {
                 *op_errno = 0;
@@ -402,7 +410,8 @@ posix_set_mdata_xattr_legacy_files(xlator_t *this, inode_t *inode,
                 mdata->mtime.tv_sec = mdata_iatt->ia_mtime;
                 mdata->mtime.tv_nsec = mdata_iatt->ia_mtime_nsec;
 
-                __inode_ctx_set1(inode, this, (uint64_t *)&mdata);
+                ctx = (uint64_t)(uintptr_t)mdata;
+                __inode_ctx_set1(inode, this, &ctx);
             }
         }
 
@@ -451,6 +460,7 @@ posix_set_mdata_xattr(xlator_t *this, const char *real_path, int fd,
                       struct iatt *stbuf, posix_mdata_flag_t *flag,
                       gf_boolean_t update_utime)
 {
+    uint64_t ctx;
     posix_mdata_t *mdata = NULL;
     int ret = -1;
     int op_errno = 0;
@@ -466,7 +476,10 @@ posix_set_mdata_xattr(xlator_t *this, const char *real_path, int fd,
 
     LOCK(&inode->lock);
     {
-        ret = __inode_ctx_get1(inode, this, (uint64_t *)&mdata);
+        ret = __inode_ctx_get1(inode, this, &ctx);
+        if (ret == 0) {
+            mdata = (posix_mdata_t *)(uintptr_t)ctx;
+        }
         if (ret == -1 || !mdata) {
             /*
              * Do we need to fetch the data from xattr
@@ -489,7 +502,8 @@ posix_set_mdata_xattr(xlator_t *this, const char *real_path, int fd,
                  * is hit when in-memory status is lost due to brick
                  * down scenario
                  */
-                __inode_ctx_set1(inode, this, (uint64_t *)&mdata);
+                ctx = (uint64_t)(uintptr_t)mdata;
+                __inode_ctx_set1(inode, this, &ctx);
             } else {
                 /*
                  * This is the first time creating the time attr. This happens
@@ -523,7 +537,8 @@ posix_set_mdata_xattr(xlator_t *this, const char *real_path, int fd,
                 mdata->mtime.tv_sec = time->tv_sec;
                 mdata->mtime.tv_nsec = time->tv_nsec;
 
-                __inode_ctx_set1(inode, this, (uint64_t *)&mdata);
+                ctx = (uint64_t)(uintptr_t)mdata;
+                __inode_ctx_set1(inode, this, &ctx);
             }
         }