From: Yehor Malikov <[email protected]>

The fdset_event_dispatch thread runs in a loop checking the destroy
flag after each epoll_wait iteration. During process exit,
rte_eal_cleanup() frees hugepage memory while the fdset thread is
still running. Since the fdset structure was allocated with
rte_zmalloc() (hugepage-backed), accessing it after rte_eal_cleanup()
causes use-after-free.

Switch fdset allocation from rte_zmalloc/rte_free to libc
calloc/free. The fdset is a control-path structure that does not
need hugepage memory. Using libc allocation ensures the fdset
remains valid after rte_eal_cleanup() releases hugepages.

Fixes: e68a6feaa3b3 ("vhost: improve fdset initialization")

Signed-off-by: Yehor Malikov <[email protected]>
---
 .mailmap           | 1 +
 lib/vhost/fd_man.c | 7 ++++---
 2 files changed, 5 insertions(+), 3 deletions(-)

diff --git a/.mailmap b/.mailmap
index fc53ed2a55..711a6ceff5 100644
--- a/.mailmap
+++ b/.mailmap
@@ -1840,6 +1840,7 @@ Yaroslav Brustinov <[email protected]>
 Yash Sharma <[email protected]>
 Yasufumi Ogawa <[email protected]> <[email protected]>
 Yelena Krivosheev <[email protected]>
+Yehor Malikov <[email protected]>
 Yerden Zhumabekov <[email protected]> <[email protected]>
 Yevgeny Kliteynik <[email protected]>
 Yi Chen <[email protected]>
diff --git a/lib/vhost/fd_man.c b/lib/vhost/fd_man.c
index f9147edee7..fae6d787b6 100644
--- a/lib/vhost/fd_man.c
+++ b/lib/vhost/fd_man.c
@@ -8,9 +8,10 @@
 #include <sys/epoll.h>
 #include <unistd.h>
 
+#include <stdlib.h>
+
 #include <rte_common.h>
 #include <rte_log.h>
-#include <rte_malloc.h>
 #include <rte_string_fns.h>
 #include <rte_thread.h>
 
@@ -94,7 +95,7 @@ fdset_init(const char *name)
                return fdset;
        }
 
-       fdset = rte_zmalloc(NULL, sizeof(*fdset), 0);
+       fdset = calloc(1, sizeof(*fdset));
        if (!fdset) {
                VHOST_FDMAN_LOG(ERR, "failed to alloc fdset %s", name);
                goto err_unlock;
@@ -142,7 +143,7 @@ fdset_init(const char *name)
 err_epoll:
        close(fdset->epfd);
 err_free:
-       rte_free(fdset);
+       free(fdset);
 err_unlock:
        pthread_mutex_unlock(&fdsets_mutex);
 
-- 
2.52.0

Reply via email to