Re: [libvirt] [PATCH] Allocate buffer to hold xend response

Subject: [PATCH] Allocate buffer to hold xend response There are cases when a response from xend can exceed 4096 bytes, in which case anything beyond 4096 is ignored. This patch changes the current fixed-size, stack-allocated buffer to a dynamically allocated buffer based on Content-Length in HTTP header. --- src/xen/xend_internal.c | 80 ++++++++++++++++++++++++----------------------- 1 files changed, 41 insertions(+), 39 deletions(-) diff --git a/src/xen/xend_internal.c b/src/xen/xend_internal.c index e763bad..0c1a738 100644 --- a/src/xen/xend_internal.c +++ b/src/xen/xend_internal.c @@ -302,17 +302,19 @@ istartswith(const char *haystack, const char *needle) * xend_req: * @fd: the file descriptor * @content: the buffer to store the content - * @n_content: the size of the buffer * * Read the HTTP response from a Xen Daemon request. + * If the response contains content, memory is allocated to + * hold the content. * - * Returns the HTTP return code. + * Returns the HTTP return code and @content is set to the + * allocated memory containing HTTP content. */ static int -xend_req(int fd, char *content, size_t n_content) +xend_req(int fd, char **content) { char buffer[4096]; - int content_length = -1; + int content_length = 0; int retcode = 0; while (sreads(fd, buffer, sizeof(buffer)) > 0) { @@ -325,19 +327,17 @@ xend_req(int fd, char *content, size_t n_content) retcode = atoi(buffer + 9); } - if (content_length > -1) { + if (content_length > 0) { ssize_t ret; - if ((unsigned int) content_length > (n_content + 1)) - content_length = n_content - 1; + if (VIR_ALLOC_N(*content, content_length) < 0 ) { + virReportOOMError(); + return -1; + } - ret = sread(fd, content, content_length); + ret = sread(fd, *content, content_length); if (ret < 0) return -1; - - content[ret] = 0; - } else { - content[0] = 0; }