> On May 5, 2016, at 10:17 AM, Steve Dickson <SteveD@xxxxxxxxxx> wrote:
>
> Hello,
>
> On 05/04/2016 10:15 AM, Kornievskaia, Olga wrote:
>> I’m having a hard time picturing what you have in mind. I don’t see how you can allocate,
>> populate and free in one routine. The logic is we allocate memory, then read the upcall
>> and only then we create the thread. If either upcall or creation of the thread
>> fails we need to free the allocated memory.
> Something like this:
>
> gssd_clnt_gssd_cb(int UNUSED(fd), short UNUSED(which), void *data)
> {
> struct clnt_info *clp = data;
> - pthread_t th;
> - int ret;
> + struct clnt_upcall_info *info;
>
> - ret = pthread_create(&th, NULL, (void *)handle_gssd_upcall,
> - (void *)clp);
> - if (ret != 0) {
> - printerr(0, "ERROR: pthread_create failed: ret %d: %s\n",
> - ret, strerror(errno));
> + info = alloc_upcall_info(clp);
> + if (info == NULL)
> + return;
> +
> + info->lbuflen = read(clp->gssd_fd, info->lbuf, sizeof(info->lbuf));
> + if (info->lbuflen <= 0 || info->lbuf[info->lbuflen-1] != '\n') {
> + printerr(0, "WARNING: %s: failed reading request\n", __func__);
> + free(info);
> return;
> }
> - wait_for_child_and_detach(th);
> + info->lbuf[info->lbuflen-1] = 0;
> +
> + start_upcall_thread(handle_gssd_upcall, info);
> +
> + free(info);
> + return;
Gotcha! Sounds good! You can make the modifications. Or just in case since you are traveling, I’ll just send another patch. Please also add any other lines like Modified-by or Signed-off-by that are need.
> }
>
> static void
> gssd_clnt_krb5_cb(int UNUSED(fd), short UNUSED(which), void *data)
> {
> struct clnt_info *clp = data;
> - pthread_t th;
> - int ret;
> + struct clnt_upcall_info *info;
>
> - ret = pthread_create(&th, NULL, (void *)handle_krb5_upcall,
> - (void *)clp);
> - if (ret != 0) {
> - printerr(0, "ERROR: pthread_create failed: ret %d: %s\n",
> - ret, strerror(errno));
> + info = alloc_upcall_info(clp);
> + if (info == NULL)
> + return;
> +
> + if (read(clp->krb5_fd, &info->uid,
> + sizeof(info->uid)) < (ssize_t)sizeof(info->uid)) {
> + printerr(0, "WARNING: %s: failed reading uid from krb5 "
> + "upcall pipe: %s\n", __func__, strerror(errno));
> + free(info);
> return;
> }
> - wait_for_child_and_detach(th);
> +
> + start_upcall_thread(handle_krb5_upcall, info);
> +
> + free(info);
> + return;
> }
>
> Then utils/gssd/gssd_proc.c looks something like this:
>
> diff --git a/utils/gssd/gssd_proc.c b/utils/gssd/gssd_proc.c
> index afaaf9e..f1bd571 100644
> --- a/utils/gssd/gssd_proc.c
> +++ b/utils/gssd/gssd_proc.c
> @@ -79,7 +79,6 @@
> #include "nfsrpc.h"
> #include "nfslib.h"
> #include "gss_names.h"
> -#include "misc.h"
>
> /* Encryption types supported by the kernel rpcsec_gss code */
> int num_krb5_enctypes = 0;
> @@ -708,45 +707,21 @@ out_return_error:
> goto out;
> }
>
> -/* signal to the parent thread that we have read from the file descriptor.
> - * it should allow the parent to proceed to poll on the descriptor for
> - * the next upcall from the kernel.
> - */
> -static inline void
> -signal_parent_event_consumed(void)
> -{
> - pthread_mutex_lock(&pmutex);
> - thread_started = true;
> - pthread_cond_signal(&pcond);
> - pthread_mutex_unlock(&pmutex);
> -}
> -
> void
> -handle_krb5_upcall(struct clnt_info *clp)
> +handle_krb5_upcall(struct clnt_upcall_info *info)
> {
> - uid_t uid;
> - int status;
> -
> - status = read(clp->krb5_fd, &uid, sizeof(uid)) < (ssize_t)sizeof(uid);
> - signal_parent_event_consumed();
> -
> - if (status) {
> - printerr(0, "WARNING: failed reading uid from krb5 "
> - "upcall pipe: %s\n", strerror(errno));
> - return;
> - }
> + struct clnt_info *clp = info->clp;
>
> - printerr(2, "\n%s: uid %d (%s)\n", __func__, uid, clp->relpath);
> + printerr(2, "\n%s: uid %d (%s)\n", __func__, info->uid, clp->relpath);
>
> - process_krb5_upcall(clp, uid, clp->krb5_fd, NULL, NULL);
> + process_krb5_upcall(clp, info->uid, clp->krb5_fd, NULL, NULL);
> }
>
> void
> -handle_gssd_upcall(struct clnt_info *clp)
> +handle_gssd_upcall(struct clnt_upcall_info *info)
> {
> + struct clnt_info *clp = info->clp;
> uid_t uid;
> - char lbuf[RPC_CHAN_BUF_SIZE];
> - int lbuflen = 0;
> char *p;
> char *mech = NULL;
> char *uidstr = NULL;
> @@ -754,19 +729,9 @@ handle_gssd_upcall(struct clnt_info *clp)
> char *service = NULL;
> char *enctypes = NULL;
>
> - lbuflen = read(clp->gssd_fd, lbuf, sizeof(lbuf));
> - signal_parent_event_consumed();
> -
> - if (lbuflen <= 0 || lbuf[lbuflen-1] != '\n') {
> - printerr(0, "WARNING: handle_gssd_upcall: "
> - "failed reading request\n");
> - return;
> - }
> - lbuf[lbuflen-1] = 0;
> -
> - printerr(2, "\n%s: '%s' (%s)\n", __func__, lbuf, clp->relpath);
> + printerr(2, "\n%s: '%s' (%s)\n", __func__, info->lbuf, clp->relpath);
>
> - for (p = strtok(lbuf, " "); p; p = strtok(NULL, " ")) {
> + for (p = strtok(info->lbuf, " "); p; p = strtok(NULL, " ")) {
> if (!strncmp(p, "mech=", strlen("mech=")))
> mech = p + strlen("mech=");
> else if (!strncmp(p, "uid=", strlen("uid=")))
> @@ -782,7 +747,7 @@ handle_gssd_upcall(struct clnt_info *clp)
> if (!mech || strlen(mech) < 1) {
> printerr(0, "WARNING: handle_gssd_upcall: "
> "failed to find gss mechanism name "
> - "in upcall string '%s'\n", lbuf);
> + "in upcall string '%s'\n", info->lbuf);
> return;
> }
>
> @@ -795,7 +760,7 @@ handle_gssd_upcall(struct clnt_info *clp)
> if (!uidstr) {
> printerr(0, "WARNING: handle_gssd_upcall: "
> "failed to find uid "
> - "in upcall string '%s'\n", lbuf);
> + "in upcall string '%s'\n", info->lbuf);
> return;
> }
>
> @@ -808,7 +773,7 @@ handle_gssd_upcall(struct clnt_info *clp)
> if (target && strlen(target) < 1) {
> printerr(0, "WARNING: handle_gssd_upcall: "
> "failed to parse target name "
> - "in upcall string '%s'\n", lbuf);
> + "in upcall string '%s'\n", info->lbuf);
> return;
> }
>
> @@ -823,7 +788,7 @@ handle_gssd_upcall(struct clnt_info *clp)
> if (service && strlen(service) < 1) {
> printerr(0, "WARNING: handle_gssd_upcall: "
> "failed to parse service type "
> - "in upcall string '%s'\n", lbuf);
> + "in upcall string '%s'\n", info->lbuf);
> return;
> }
>
> @@ -835,5 +800,7 @@ handle_gssd_upcall(struct clnt_info *clp)
> "received unknown gss mech '%s'\n", mech);
> do_error_downcall(clp->gssd_fd, uid, -EACCES);
> }
> +
> + return;
> }
>
> steved.
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