On Sat, 30 Nov 2019 20:42:27 +0100
Markus Armbruster <arm...@redhat.com> wrote:
> When os_mem_prealloc() fails, file_ram_alloc() calls qemu_ram_munmap()
> and returns null. Except it doesn't when its @errp argument is null,
> because it checks for failure with (errp && *errp). Messed up in
> commit 056b68af77 "fix qemu exit on memory hotplug when allocation
> fails at prealloc time".
>
> The bug can't bite as no caller actually passes null. Fix it anyway.
>
> Cc: Igor Mammedov <imamm...@redhat.com>
> Signed-off-by: Markus Armbruster <arm...@redhat.com>
Reviewed-by: Igor Mammedov <imamm...@redhat.com>
> ---
> exec.c | 6 ++++--
> 1 file changed, 4 insertions(+), 2 deletions(-)
>
> diff --git a/exec.c b/exec.c
> index ffdb518535..45695a5f2d 100644
> --- a/exec.c
> +++ b/exec.c
> @@ -1841,6 +1841,7 @@ static void *file_ram_alloc(RAMBlock *block,
> bool truncate,
> Error **errp)
> {
> + Error *err = NULL;
> MachineState *ms = MACHINE(qdev_get_machine());
> void *area;
>
> @@ -1898,8 +1899,9 @@ static void *file_ram_alloc(RAMBlock *block,
> }
>
> if (mem_prealloc) {
> - os_mem_prealloc(fd, area, memory, ms->smp.cpus, errp);
> - if (errp && *errp) {
> + os_mem_prealloc(fd, area, memory, ms->smp.cpus, &err);
> + if (err) {
> + error_propagate(errp, err);
> qemu_ram_munmap(fd, area, memory);
> return NULL;
> }
