From: Igor Mammedov <imamm...@redhat.com>
if MemoryRegion intialization fails it's left in semi-initialized state,
where it's size is not 0 and attached as child to owner object.
And this leds to crash in following use-case:
(monitor) object_add
memory-backend-file,id=mem1,size=99999G,mem-path=/tmp/foo,discard-data=yes
memory.c:2083: memory_region_get_ram_ptr: Assertion `mr->ram_block' failed
Aborted (core dumped)
it happens due to assumption that memory region is intialized when
memory_region_size() != 0
and therefore it's ok to access it in
file_backend_unparent()
if (memory_region_size() != 0)
memory_region_get_ram_ptr()
which happens when object_add fails and unparents failed backend making
file_backend_unparent() access invalid memory region.
Fix it by making sure that memory_region_init_foo() APIs cleanup externally
visible side effects on failure (like set size to 0 and unparenting object)
Signed-off-by: Igor Mammedov <imamm...@redhat.com>
Message-Id: <1536064777-42312-1-git-send-email-imamm...@redhat.com>
Signed-off-by: Paolo Bonzini <pbonz...@redhat.com>
---
memory.c | 48 ++++++++++++++++++++++++++++++++++++++++++------
1 file changed, 42 insertions(+), 6 deletions(-)
diff --git a/memory.c b/memory.c
index 9b73892..aceadb2 100644
--- a/memory.c
+++ b/memory.c
@@ -1518,12 +1518,18 @@ void
memory_region_init_ram_shared_nomigrate(MemoryRegion *mr,
bool share,
Error **errp)
{
+ Error *err = NULL;
memory_region_init(mr, owner, name, size);
mr->ram = true;
mr->terminates = true;
mr->destructor = memory_region_destructor_ram;
- mr->ram_block = qemu_ram_alloc(size, share, mr, errp);
+ mr->ram_block = qemu_ram_alloc(size, share, mr, &err);
mr->dirty_log_mask = tcg_enabled() ? (1 << DIRTY_MEMORY_CODE) : 0;
+ if (err) {
+ mr->size = int128_zero();
+ object_unparent(OBJECT(mr));
+ error_propagate(errp, err);
+ }
}
void memory_region_init_resizeable_ram(MemoryRegion *mr,
@@ -1536,13 +1542,19 @@ void memory_region_init_resizeable_ram(MemoryRegion *mr,
void *host),
Error **errp)
{
+ Error *err = NULL;
memory_region_init(mr, owner, name, size);
mr->ram = true;
mr->terminates = true;
mr->destructor = memory_region_destructor_ram;
mr->ram_block = qemu_ram_alloc_resizeable(size, max_size, resized,
- mr, errp);
+ mr, &err);
mr->dirty_log_mask = tcg_enabled() ? (1 << DIRTY_MEMORY_CODE) : 0;
+ if (err) {
+ mr->size = int128_zero();
+ object_unparent(OBJECT(mr));
+ error_propagate(errp, err);
+ }
}
#ifdef __linux__
@@ -1555,13 +1567,19 @@ void memory_region_init_ram_from_file(MemoryRegion *mr,
const char *path,
Error **errp)
{
+ Error *err = NULL;
memory_region_init(mr, owner, name, size);
mr->ram = true;
mr->terminates = true;
mr->destructor = memory_region_destructor_ram;
mr->align = align;
- mr->ram_block = qemu_ram_alloc_from_file(size, mr, ram_flags, path, errp);
+ mr->ram_block = qemu_ram_alloc_from_file(size, mr, ram_flags, path, &err);
mr->dirty_log_mask = tcg_enabled() ? (1 << DIRTY_MEMORY_CODE) : 0;
+ if (err) {
+ mr->size = int128_zero();
+ object_unparent(OBJECT(mr));
+ error_propagate(errp, err);
+ }
}
void memory_region_init_ram_from_fd(MemoryRegion *mr,
@@ -1572,14 +1590,20 @@ void memory_region_init_ram_from_fd(MemoryRegion *mr,
int fd,
Error **errp)
{
+ Error *err = NULL;
memory_region_init(mr, owner, name, size);
mr->ram = true;
mr->terminates = true;
mr->destructor = memory_region_destructor_ram;
mr->ram_block = qemu_ram_alloc_from_fd(size, mr,
share ? RAM_SHARED : 0,
- fd, errp);
+ fd, &err);
mr->dirty_log_mask = tcg_enabled() ? (1 << DIRTY_MEMORY_CODE) : 0;
+ if (err) {
+ mr->size = int128_zero();
+ object_unparent(OBJECT(mr));
+ error_propagate(errp, err);
+ }
}
#endif
@@ -1630,13 +1654,19 @@ void memory_region_init_rom_nomigrate(MemoryRegion *mr,
uint64_t size,
Error **errp)
{
+ Error *err = NULL;
memory_region_init(mr, owner, name, size);
mr->ram = true;
mr->readonly = true;
mr->terminates = true;
mr->destructor = memory_region_destructor_ram;
- mr->ram_block = qemu_ram_alloc(size, false, mr, errp);
+ mr->ram_block = qemu_ram_alloc(size, false, mr, &err);
mr->dirty_log_mask = tcg_enabled() ? (1 << DIRTY_MEMORY_CODE) : 0;
+ if (err) {
+ mr->size = int128_zero();
+ object_unparent(OBJECT(mr));
+ error_propagate(errp, err);
+ }
}
void memory_region_init_rom_device_nomigrate(MemoryRegion *mr,
@@ -1647,6 +1677,7 @@ void memory_region_init_rom_device_nomigrate(MemoryRegion
*mr,
uint64_t size,
Error **errp)
{
+ Error *err = NULL;
assert(ops);
memory_region_init(mr, owner, name, size);
mr->ops = ops;
@@ -1654,7 +1685,12 @@ void
memory_region_init_rom_device_nomigrate(MemoryRegion *mr,
mr->terminates = true;
mr->rom_device = true;
mr->destructor = memory_region_destructor_ram;
- mr->ram_block = qemu_ram_alloc(size, false, mr, errp);
+ mr->ram_block = qemu_ram_alloc(size, false, mr, &err);
+ if (err) {
+ mr->size = int128_zero();
+ object_unparent(OBJECT(mr));
+ error_propagate(errp, err);
+ }
}
void memory_region_init_iommu(void *_iommu_mr,
--
1.8.3.1
