From 319ae529b8d55ea60b1036809aaab2130048d0e1 Mon Sep 17 00:00:00 2001 From: Markus Armbruster Date: Fri, 28 Jan 2011 11:21:46 +0100 Subject: [PATCH] blockdev: Fix drive_add for drives without media Watch this: (qemu) drive_add 0 if=none (qemu) info block none0: type=hd removable=0 [not inserted] (qemu) drive_del none0 Segmentation fault (core dumped) add_init_drive() is confused about drive_init()'s failure modes, and cleans up when it shouldn't. This leaves the DriveInfo with member opts dangling. drive_del attempts to free it, and dies. drive_init() behaves as follows: * If it created a drive with media, it returns its DriveInfo. * If it created a drive without media, it clears *fatal_error and returns NULL. * If it couldn't create a drive, it sets *fatal_error and returns NULL. Of its three callers: * drive_init_func() is correct. * usb_msd_init() assumes drive_init() failed when it returns NULL. This is correct only because it always passes option "file", and "drive without media" can't happen then. * add_init_drive() assumes drive_init() failed when it returns NULL. This is incorrect. Clean up drive_init() to return NULL on failure and only on failure. Drop its parameter fatal_error. Signed-off-by: Markus Armbruster Signed-off-by: Kevin Wolf --- blockdev.c | 8 ++------ blockdev.h | 2 +- hw/device-hotplug.c | 3 +-- hw/usb-msd.c | 3 +-- vl.c | 9 ++------- 5 files changed, 7 insertions(+), 18 deletions(-) diff --git a/blockdev.c b/blockdev.c index 4b2145c25b..1c56da0a16 100644 --- a/blockdev.c +++ b/blockdev.c @@ -203,7 +203,7 @@ static int parse_block_error_action(const char *buf, int is_read) } } -DriveInfo *drive_init(QemuOpts *opts, int default_to_scsi, int *fatal_error) +DriveInfo *drive_init(QemuOpts *opts, int default_to_scsi) { const char *buf; const char *file = NULL; @@ -225,8 +225,6 @@ DriveInfo *drive_init(QemuOpts *opts, int default_to_scsi, int *fatal_error) int snapshot = 0; int ret; - *fatal_error = 1; - translation = BIOS_ATA_TRANSLATION_AUTO; if (default_to_scsi) { @@ -499,8 +497,7 @@ DriveInfo *drive_init(QemuOpts *opts, int default_to_scsi, int *fatal_error) abort(); } if (!file || !*file) { - *fatal_error = 0; - return NULL; + return dinfo; } if (snapshot) { /* always use cache=unsafe with snapshot */ @@ -529,7 +526,6 @@ DriveInfo *drive_init(QemuOpts *opts, int default_to_scsi, int *fatal_error) if (bdrv_key_required(dinfo->bdrv)) autostart = 0; - *fatal_error = 0; return dinfo; } diff --git a/blockdev.h b/blockdev.h index e5d8c56bfb..84e462ab3f 100644 --- a/blockdev.h +++ b/blockdev.h @@ -48,7 +48,7 @@ DriveInfo *drive_get_by_blockdev(BlockDriverState *bs); QemuOpts *drive_def(const char *optstr); QemuOpts *drive_add(BlockInterfaceType type, int index, const char *file, const char *optstr); -DriveInfo *drive_init(QemuOpts *arg, int default_to_scsi, int *fatal_error); +DriveInfo *drive_init(QemuOpts *arg, int default_to_scsi); /* device-hotplug */ diff --git a/hw/device-hotplug.c b/hw/device-hotplug.c index 95a63726f3..8b2ed7a492 100644 --- a/hw/device-hotplug.c +++ b/hw/device-hotplug.c @@ -29,7 +29,6 @@ DriveInfo *add_init_drive(const char *optstr) { - int fatal_error; DriveInfo *dinfo; QemuOpts *opts; @@ -37,7 +36,7 @@ DriveInfo *add_init_drive(const char *optstr) if (!opts) return NULL; - dinfo = drive_init(opts, current_machine->use_scsi, &fatal_error); + dinfo = drive_init(opts, current_machine->use_scsi); if (!dinfo) { qemu_opts_del(opts); return NULL; diff --git a/hw/usb-msd.c b/hw/usb-msd.c index 11722c7486..97d1e4af13 100644 --- a/hw/usb-msd.c +++ b/hw/usb-msd.c @@ -542,7 +542,6 @@ static USBDevice *usb_msd_init(const char *filename) QemuOpts *opts; DriveInfo *dinfo; USBDevice *dev; - int fatal_error; const char *p1; char fmt[32]; @@ -572,7 +571,7 @@ static USBDevice *usb_msd_init(const char *filename) qemu_opt_set(opts, "if", "none"); /* create host drive */ - dinfo = drive_init(opts, 0, &fatal_error); + dinfo = drive_init(opts, 0); if (!dinfo) { qemu_opts_del(opts); return NULL; diff --git a/vl.c b/vl.c index f86724f83a..ce5708bbbd 100644 --- a/vl.c +++ b/vl.c @@ -631,13 +631,8 @@ static int bt_parse(const char *opt) static int drive_init_func(QemuOpts *opts, void *opaque) { int *use_scsi = opaque; - int fatal_error = 0; - if (drive_init(opts, *use_scsi, &fatal_error) == NULL) { - if (fatal_error) - return 1; - } - return 0; + return drive_init(opts, *use_scsi) == NULL; } static int drive_enable_snapshot(QemuOpts *opts, void *opaque) @@ -666,7 +661,7 @@ static void default_drive(int enable, int snapshot, int use_scsi, if (snapshot) { drive_enable_snapshot(opts, NULL); } - if (drive_init_func(opts, &use_scsi)) { + if (!drive_init(opts, use_scsi)) { exit(1); } }