Fix vn_open/vn_rdwr error handling

1) In vn_open(), if fstat64() returned an error, the real errno
was being obscured by calling close().

2) Add error handling for both pwrite64() calls in vn_rdwr().

Signed-off-by: Ricardo M. Correia <Ricardo.M.Correia@Sun.COM>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>

diff --git a/lib/libzpool/kernel.c b/lib/libzpool/kernel.c
index ef264061f97769482c884a99ed9ba01333dc9aa5..adbe6ba085cff37f263a7fec0cea717a942a074a 100644 (file)
--- a/lib/libzpool/kernel.c
+++ b/lib/libzpool/kernel.c
@@ -328,6 +328,7 @@ vn_open(char *path, int x1, int flags, int mode, vnode_t **vpp, int x2, int x3)
        int old_umask;
        char realpath[MAXPATHLEN];
        struct stat64 st;
+       int err;
 
        /*
         * If we're accessing a real disk from userland, we need to use
@@ -376,8 +377,9 @@ vn_open(char *path, int x1, int flags, int mode, vnode_t **vpp, int x2, int x3)
                return (errno);
 
        if (fstat64(fd, &st) == -1) {
+               err = errno;
                close(fd);
-               return (errno);
+               return (err);
        }
 
        (void) fcntl(fd, F_SETFD, FD_CLOEXEC);
@@ -415,26 +417,32 @@ int
 vn_rdwr(int uio, vnode_t *vp, void *addr, ssize_t len, offset_t offset,
        int x1, int x2, rlim64_t x3, void *x4, ssize_t *residp)
 {
-       ssize_t iolen, split;
+       ssize_t rc, done = 0, split;
 
        if (uio == UIO_READ) {
-               iolen = pread64(vp->v_fd, addr, len, offset);
+               rc = pread64(vp->v_fd, addr, len, offset);
        } else {
                /*
                 * To simulate partial disk writes, we split writes into two
                 * system calls so that the process can be killed in between.
                 */
                split = (len > 0 ? rand() % len : 0);
-               iolen = pwrite64(vp->v_fd, addr, split, offset);
-               iolen += pwrite64(vp->v_fd, (char *)addr + split,
-                   len - split, offset + split);
+               rc = pwrite64(vp->v_fd, addr, split, offset);
+               if (rc != -1) {
+                       done = rc;
+                       rc = pwrite64(vp->v_fd, (char *)addr + split,
+                           len - split, offset + split);
+               }
        }
 
-       if (iolen == -1)
+       if (rc == -1)
                return (errno);
+
+       done += rc;
+
        if (residp)
-               *residp = len - iolen;
-       else if (iolen != len)
+               *residp = len - done;
+       else if (done != len)
                return (EIO);
        return (0);
 }