| Message ID | 20200120074725.22948-1-pannengyuan@huawei.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | backup-top: fix a memory leak in bdrv_backup_top_append() | expand |
Hi Pan! Better is to drop extra allocation. Correct patch already posted here: https://lists.gnu.org/archive/html/qemu-devel/2019-12/msg05067.html 20.01.2020 10:47, pannengyuan@huawei.com wrote: > From: Pan Nengyuan <pannengyuan@huawei.com> > > top->opaque is aleardy malloced in bdrv_new_open_driver(), and then change > the pointer but without freeing it. It will cause a memory leak, the leak > stack is as follow: > > Direct leak of 24 byte(s) in 1 object(s) allocated from: > #0 0x7ff6f7be4970 (/lib64/libasan.so.5+0xef970) ??:? > #1 0x7ff6f723849d (/lib64/libglib-2.0.so.0+0x5249d) ??:? > #2 0x564c0d44caae (./x86_64-softmmu/qemu-system-x86_64+0x3b40aae) /mnt/sdb/qemu/block.c:1289 > #3 0x564c0d44dbaf (./x86_64-softmmu/qemu-system-x86_64+0x3b41baf) /mnt/sdb/qemu/block.c:1359 > #4 0x564c0d71618f (./x86_64-softmmu/qemu-system-x86_64+0x3e0a18f) /mnt/sdb/qemu/block/backup-top.c:190 > #5 0x564c0d7001be (./x86_64-softmmu/qemu-system-x86_64+0x3df41be) /mnt/sdb/qemu/block/backup.c:439 > #6 0x564c0c8ebef8 (./x86_64-softmmu/qemu-system-x86_64+0x2fdfef8) /mnt/sdb/qemu/blockdev.c:3580 > #7 0x564c0c8ed0cb (./x86_64-softmmu/qemu-system-x86_64+0x2fe10cb) /mnt/sdb/qemu/blockdev.c:3690 > #8 0x564c0c8ed177 (./x86_64-softmmu/qemu-system-x86_64+0x2fe1177) /mnt/sdb/qemu/blockdev.c:3704 > #9 0x564c0d316388 (./x86_64-softmmu/qemu-system-x86_64+0x3a0a388) /mnt/sdb/qemu/build/qapi/qapi-commands-block-core.c:439 > #10 0x564c0d7ff7fa (./x86_64-softmmu/qemu-system-x86_64+0x3ef37fa) /mnt/sdb/qemu/qapi/qmp-dispatch.c:132 > #11 0x564c0d7ffcb8 (./x86_64-softmmu/qemu-system-x86_64+0x3ef3cb8) /mnt/sdb/qemu/qapi/qmp-dispatch.c:175 (discriminator 4) > #12 0x564c0d2704ef (./x86_64-softmmu/qemu-system-x86_64+0x39644ef) /mnt/sdb/qemu/monitor/qmp.c:145 > #13 0x564c0d2712de (./x86_64-softmmu/qemu-system-x86_64+0x39652de) /mnt/sdb/qemu/monitor/qmp.c:234 (discriminator 4) > > Reported-by: Euler Robot <euler.robot@huawei.com> > Signed-off-by: Pan Nengyuan <pannengyuan@huawei.com> > --- > block/backup-top.c | 1 + > 1 file changed, 1 insertion(+) > > diff --git a/block/backup-top.c b/block/backup-top.c > index 818d3f26b4..d565f05520 100644 > --- a/block/backup-top.c > +++ b/block/backup-top.c > @@ -196,6 +196,7 @@ BlockDriverState *bdrv_backup_top_append(BlockDriverState *source, > } > > top->total_sectors = source->total_sectors; > + g_free(top->opaque); > top->opaque = state = g_new0(BDRVBackupTopState, 1); > > bdrv_ref(target); >
On 1/20/2020 4:38 PM, Vladimir Sementsov-Ogievskiy wrote: > Hi Pan! > > Better is to drop extra allocation. Correct patch already posted here: > https://lists.gnu.org/archive/html/qemu-devel/2019-12/msg05067.html > Yes, it's better. Thanks. > 20.01.2020 10:47, pannengyuan@huawei.com wrote: >> From: Pan Nengyuan <pannengyuan@huawei.com> >> >> top->opaque is aleardy malloced in bdrv_new_open_driver(), and then change >> the pointer but without freeing it. It will cause a memory leak, the leak >> stack is as follow: >> >> Direct leak of 24 byte(s) in 1 object(s) allocated from: >> #0 0x7ff6f7be4970 (/lib64/libasan.so.5+0xef970) ??:? >> #1 0x7ff6f723849d (/lib64/libglib-2.0.so.0+0x5249d) ??:? >> #2 0x564c0d44caae (./x86_64-softmmu/qemu-system-x86_64+0x3b40aae) /mnt/sdb/qemu/block.c:1289 >> #3 0x564c0d44dbaf (./x86_64-softmmu/qemu-system-x86_64+0x3b41baf) /mnt/sdb/qemu/block.c:1359 >> #4 0x564c0d71618f (./x86_64-softmmu/qemu-system-x86_64+0x3e0a18f) /mnt/sdb/qemu/block/backup-top.c:190 >> #5 0x564c0d7001be (./x86_64-softmmu/qemu-system-x86_64+0x3df41be) /mnt/sdb/qemu/block/backup.c:439 >> #6 0x564c0c8ebef8 (./x86_64-softmmu/qemu-system-x86_64+0x2fdfef8) /mnt/sdb/qemu/blockdev.c:3580 >> #7 0x564c0c8ed0cb (./x86_64-softmmu/qemu-system-x86_64+0x2fe10cb) /mnt/sdb/qemu/blockdev.c:3690 >> #8 0x564c0c8ed177 (./x86_64-softmmu/qemu-system-x86_64+0x2fe1177) /mnt/sdb/qemu/blockdev.c:3704 >> #9 0x564c0d316388 (./x86_64-softmmu/qemu-system-x86_64+0x3a0a388) /mnt/sdb/qemu/build/qapi/qapi-commands-block-core.c:439 >> #10 0x564c0d7ff7fa (./x86_64-softmmu/qemu-system-x86_64+0x3ef37fa) /mnt/sdb/qemu/qapi/qmp-dispatch.c:132 >> #11 0x564c0d7ffcb8 (./x86_64-softmmu/qemu-system-x86_64+0x3ef3cb8) /mnt/sdb/qemu/qapi/qmp-dispatch.c:175 (discriminator 4) >> #12 0x564c0d2704ef (./x86_64-softmmu/qemu-system-x86_64+0x39644ef) /mnt/sdb/qemu/monitor/qmp.c:145 >> #13 0x564c0d2712de (./x86_64-softmmu/qemu-system-x86_64+0x39652de) /mnt/sdb/qemu/monitor/qmp.c:234 (discriminator 4) >> >> Reported-by: Euler Robot <euler.robot@huawei.com> >> Signed-off-by: Pan Nengyuan <pannengyuan@huawei.com> >> --- >> block/backup-top.c | 1 + >> 1 file changed, 1 insertion(+) >> >> diff --git a/block/backup-top.c b/block/backup-top.c >> index 818d3f26b4..d565f05520 100644 >> --- a/block/backup-top.c >> +++ b/block/backup-top.c >> @@ -196,6 +196,7 @@ BlockDriverState *bdrv_backup_top_append(BlockDriverState *source, >> } >> >> top->total_sectors = source->total_sectors; >> + g_free(top->opaque); >> top->opaque = state = g_new0(BDRVBackupTopState, 1); >> >> bdrv_ref(target); >> > >
diff --git a/block/backup-top.c b/block/backup-top.c index 818d3f26b4..d565f05520 100644 --- a/block/backup-top.c +++ b/block/backup-top.c @@ -196,6 +196,7 @@ BlockDriverState *bdrv_backup_top_append(BlockDriverState *source, } top->total_sectors = source->total_sectors; + g_free(top->opaque); top->opaque = state = g_new0(BDRVBackupTopState, 1); bdrv_ref(target);