kernel/linux.git/include/linux/cdrom.h, branch v6.19.11

cdrom: Call cdrom_mrw_exit from cdrom_release function

2025-07-23T01:10:17+00:00

Remove the cdrom_mrw_exit call from unregister_cdrom, as it invokes block commands that can fail due to a NULL pointer dereference from the call happening too late, during the unloading of the driver (e.g. unplugging of USB optical drives). Instead perform the call inside cdrom_release, thus also removing the need for the exit function pointer inside the cdrom_device_info struct. Reported-by: Sergey Senozhatsky Closes: https://lore.kernel.org/linux-block/uxgzea5ibqxygv3x7i4ojbpvcpv2wziorvb3ns5cdtyvobyn7h@y4g4l5ezv2ec Suggested-by: Jens Axboe Link: https://lore.kernel.org/linux-block/6686fe78-a050-4a1d-aa27-b7bf7ca6e912@kernel.dk Tested-by: Phillip Potter Signed-off-by: Phillip Potter Link: https://lore.kernel.org/r/20250722231900.1164-2-phil@philpotter.co.uk Signed-off-by: Jens Axboe

scsi: sr: Fix unintentional arithmetic wraparound

2024-05-15T14:05:24+00:00

Running syzkaller with the newly reintroduced signed integer overflow sanitizer produces this report: [ 65.194362] ------------[ cut here ]------------ [ 65.197752] UBSAN: signed-integer-overflow in ../drivers/scsi/sr_ioctl.c:436:9 [ 65.203607] -2147483648 * 177 cannot be represented in type 'int' [ 65.207911] CPU: 2 PID: 10416 Comm: syz-executor.1 Not tainted 6.8.0-rc2-00035-gb3ef86b5a957 #1 [ 65.213585] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.3-debian-1.16.3-2 04/01/2014 [ 65.219923] Call Trace: [ 65.221556] [ 65.223029] dump_stack_lvl+0x93/0xd0 [ 65.225573] handle_overflow+0x171/0x1b0 [ 65.228219] sr_select_speed+0xeb/0xf0 [ 65.230786] ? __pm_runtime_resume+0xe6/0x130 [ 65.233606] sr_block_ioctl+0x15d/0x1d0 ... Historically, the signed integer overflow sanitizer did not work in the kernel due to its interaction with `-fwrapv` but this has since been changed [1] in the newest version of Clang. It was re-enabled in the kernel with Commit 557f8c582a9b ("ubsan: Reintroduce signed overflow sanitizer"). Firstly, let's change the type of "speed" to unsigned long as sr_select_speed()'s only caller passes in an unsigned long anyways. $ git grep '\.select_speed' | drivers/scsi/sr.c: .select_speed = sr_select_speed, ... | static int cdrom_ioctl_select_speed(struct cdrom_device_info *cdi, | unsigned long arg) | { | ... | return cdi->ops->select_speed(cdi, arg); | } Next, let's add an extra check to make sure we don't exceed 0xffff/177 (350) since 0xffff is the max speed. This has two benefits: 1) we deal with integer overflow before it happens and 2) we properly respect the max speed of 0xffff. There are some "magic" numbers here but I did not want to change more than what was necessary. Link: https://github.com/llvm/llvm-project/pull/82432 [1] Closes: https://github.com/KSPP/linux/issues/357 Cc: linux-hardening@vger.kernel.org Signed-off-by: Justin Stitt Link: https://lore.kernel.org/r/20240508-b4-b4-sio-sr_select_speed-v2-1-00b68f724290@google.com Reviewed-by: Kees Cook Signed-off-by: Martin K. Petersen

block: replace fmode_t with a block-specific type for block open flags

2023-06-12T14:04:05+00:00

The only overlap between the block open flags mapped into the fmode_t and other uses of fmode_t are FMODE_READ and FMODE_WRITE. Define a new blk_mode_t instead for use in blkdev_get_by_{dev,path}, ->open and ->ioctl and stop abusing fmode_t. Signed-off-by: Christoph Hellwig Acked-by: Jack Wang [rnbd] Reviewed-by: Hannes Reinecke Reviewed-by: Christian Brauner Link: https://lore.kernel.org/r/20230608110258.189493-28-hch@lst.de Signed-off-by: Jens Axboe

cdrom: remove the unused mode argument to cdrom_release

2023-06-12T14:04:03+00:00

Signed-off-by: Christoph Hellwig Reviewed-by: Phillip Potter Reviewed-by: Hannes Reinecke Acked-by: Christian Brauner Link: https://lore.kernel.org/r/20230608110258.189493-7-hch@lst.de Signed-off-by: Jens Axboe

cdrom: track if a cdrom_device_info was opened for data

2023-06-12T14:04:03+00:00

Set a flag when a cdrom_device_info is opened for writing, instead of trying to figure out this at release time. This will allow to eventually remove the mode argument to the ->release block_device_operation as nothing but the CDROM drivers uses that argument. Signed-off-by: Christoph Hellwig Reviewed-by: Phillip Potter Acked-by: Christian Brauner Reviewed-by: Hannes Reinecke Link: https://lore.kernel.org/r/20230608110258.189493-6-hch@lst.de Signed-off-by: Jens Axboe

cdrom: remove the unused cdrom_close_write release code

2023-06-12T14:04:03+00:00

cdrom_close_write is empty, and the for_data flag it is keyed off is never set. Remove all this clutter. Signed-off-by: Christoph Hellwig Reviewed-by: Phillip Potter Reviewed-by: Hannes Reinecke Acked-by: Christian Brauner Link: https://lore.kernel.org/r/20230608110258.189493-5-hch@lst.de Signed-off-by: Jens Axboe

cdrom: remove the unused mode argument to cdrom_ioctl

2023-06-12T14:04:03+00:00

cdrom: remove the unused bdev argument to cdrom_open

2023-06-12T14:04:03+00:00

cdrom: remove the unused driver specific disc change ioctl

2022-05-16T00:31:28+00:00

This was only used by the ide-cd driver, which went away in commit b7fb14d3ac63 ("ide: remove the legacy ide driver") so we might as well take advantage of that and get rid of this hook as well. Cc: Christoph Hellwig Cc: Jens Axboe Cc: Phillip Potter Signed-off-by: Paul Gortmaker Link: https://lore.kernel.org/all/20220427132436.12795-2-paul.gortmaker@windriver.com Signed-off-by: Phillip Potter Link: https://lore.kernel.org/r/20220515205833.944139-3-phil@philpotter.co.uk Signed-off-by: Jens Axboe

drivers/cdrom: improved ioctl for media change detection

2021-09-15T02:05:26+00:00

The current implementation of the CDROM_MEDIA_CHANGED ioctl relies on global state, meaning that only one process can detect a disc change while the ioctl call will return 0 for other calling processes afterwards (see bug 213267). This introduces a new cdrom ioctl, CDROM_TIMED_MEDIA_CHANGE, that works by maintaining a timestamp of the last detected disc change instead of a boolean flag: Processes calling this ioctl command can provide a timestamp of the last disc change known to them and receive an indication whether the disc was changed since then and the updated timestamp. I considered fixing the buggy behavior in the original CDROM_MEDIA_CHANGED ioctl but that would require maintaining state for each calling process in the kernel, which seems like a worse solution than introducing this new ioctl. Signed-off-by: Lukas Prediger Link: https://lore.kernel.org/all/20210912191207.74449-1-lumip@lumip.de Signed-off-by: Phillip Potter Link: https://lore.kernel.org/r/20210913230942.1188-1-phil@philpotter.co.uk Signed-off-by: Jens Axboe