From 0fc0f1fa7f86e9f1d480c6508191ca90ac10b32c Mon Sep 17 00:00:00 2001 From: Ryan Harper Date: Wed, 8 Dec 2010 10:05:00 -0600 Subject: [PATCH] blockdev: check dinfo ptr before using If a user decides to punish a guest by revoking its block device via drive_del, and subsequently also attempts to remove the pci device backing it, and the device is using blockdev_auto_del() then we get a segfault when we attempt to access dinfo->auto_del.[1] The fix is to check if drive_get_by_blockdev() actually returns a valid dinfo pointer or not. 1. (qemu) pci_add auto storage file=images/test01.raw,if=virtio,id=block1,snapshot=on (qemu) drive_del block1 (qemu) pci_del 5 *segfault* Signed-off-by: Ryan Harper Tested-by: Luiz Capitulino Signed-off-by: Kevin Wolf --- blockdev.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/blockdev.c b/blockdev.c index f6ac4398b8..3b3b82dba7 100644 --- a/blockdev.c +++ b/blockdev.c @@ -30,14 +30,16 @@ void blockdev_mark_auto_del(BlockDriverState *bs) { DriveInfo *dinfo = drive_get_by_blockdev(bs); - dinfo->auto_del = 1; + if (dinfo) { + dinfo->auto_del = 1; + } } void blockdev_auto_del(BlockDriverState *bs) { DriveInfo *dinfo = drive_get_by_blockdev(bs); - if (dinfo->auto_del) { + if (dinfo && dinfo->auto_del) { drive_uninit(dinfo); } } -- 2.11.4.GIT