When reading the console, xen overwrites the contents of the buffer,
so there is no need to zero the buffer before passing it to xen.
Instead, add a NULL at the end of the buffer.
While we are at it, change the zalloc() of the buffer back to
malloc() as it was before bdf4131 (libxl: don't leak buf in
libxl_xen_console_read_start error handling, 2013-12-03). The comment
in that commit message says that the intent of the commit was to
change malloc+memset to zalloc(), but only for the
libxl_xen_console_reader struct, not for the buffer.
Signed-off-by: Javi Merino <javi.mer...@cloud.com>
---
tools/libs/light/libxl_console.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/tools/libs/light/libxl_console.c b/tools/libs/light/libxl_console.c
index 012fd996fba9..f42f6a51ee6f 100644
--- a/tools/libs/light/libxl_console.c
+++ b/tools/libs/light/libxl_console.c
@@ -780,7 +780,7 @@ libxl_xen_console_reader *
unsigned int size = 16384 + 1;
cr = libxl__zalloc(NOGC, sizeof(libxl_xen_console_reader));
- cr->buffer = libxl__zalloc(NOGC, size);
+ cr->buffer = libxl__malloc(NOGC, size);
cr->size = size;
cr->clear = clear;
cr->incremental = 1;
@@ -808,7 +808,6 @@ int libxl_xen_console_read_line(libxl_ctx *ctx,
unsigned int nr_chars = cr->size - 1;
GC_INIT(ctx);
- memset(cr->buffer, 0, cr->size);
ret = xc_readconsolering(ctx->xch, cr->buffer, &nr_chars,
cr->clear, cr->incremental, &cr->index);
if (ret < 0) {
@@ -818,6 +817,7 @@ int libxl_xen_console_read_line(libxl_ctx *ctx,
}
if (!ret) {
if (nr_chars) {
+ cr->buffer[nr_chars] = '\0';
*line_r = cr->buffer;
ret = 1;
} else {
--
2.45.2
