From 8efdb7ba1b2acce9fb63ccc2e7982e19fdf5be86 Mon Sep 17 00:00:00 2001 From: Peter Maydell Date: Thu, 12 Aug 2021 16:15:25 +0100 Subject: [PATCH] softmmu/physmem.c: Check return value from realpath() The realpath() function can return NULL on error, so we need to check for it to avoid crashing when we try to strstr() into it. This can happen if we run out of memory, or if /sys/ is not mounted, among other situations. Fixes: Coverity 1459913, 1460474 Fixes: ce317be98db0 ("exec: fetch the alignment of Linux devdax pmem character device nodes") Signed-off-by: Peter Maydell Reviewed-by: Jingqi Liu Message-id: 20210812151525.31456-1-peter.maydell@linaro.org --- softmmu/physmem.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/softmmu/physmem.c b/softmmu/physmem.c index 31baf3a887..23e77cb771 100644 --- a/softmmu/physmem.c +++ b/softmmu/physmem.c @@ -1451,6 +1451,9 @@ static int64_t get_file_align(int fd) path = g_strdup_printf("/sys/dev/char/%d:%d", major(st.st_rdev), minor(st.st_rdev)); rpath = realpath(path, NULL); + if (!rpath) { + return -errno; + } rc = daxctl_new(&ctx); if (rc) {