Description
In the Linux kernel, the following vulnerability has been resolved: ALSA: 6fire: fix use-after-free on disconnect In usb6fire_chip_abort(), the chip struct is allocated as the card's private data (via snd_card_new with sizeof(struct sfire_chip)). When snd_card_free_when_closed() is called and no file handles are open, the card and embedded chip are freed synchronously. The subsequent chip->card = NULL write then hits freed slab memory. Call trace: usb6fire_chip_abort sound/usb/6fire/chip.c:59 [inline] usb6fire_chip_disconnect+0x348/0x358 sound/usb/6fire/chip.c:182 usb_unbind_interface+0x1a8/0x88c drivers/usb/core/driver.c:458 ... hub_event+0x1a04/0x4518 drivers/usb/core/hub.c:5953 Fix by moving the card lifecycle out of usb6fire_chip_abort() and into usb6fire_chip_disconnect(). The card pointer is saved in a local before any teardown, snd_card_disconnect() is called first to prevent new opens, URBs are aborted while chip is still valid, and snd_card_free_when_closed() is called last so chip is never accessed after the card may be freed.
Product status
1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (git) before af75b486f7e883e3422ece23c8d727e6815144a0
1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (git) before d21e8a2af4869b5890b34e081d5aeadc93e9cd5c
1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (git) before 3dc20d1981d6a67d8184498a5da272942dde1e65
1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (git) before 51f6532790b74ffdd6970bc848358a2838c1c185
6.12.83 (semver)
6.18.24 (semver)
6.19.14 (semver)
7.0.1 (semver)
References
git.kernel.org/...c/af75b486f7e883e3422ece23c8d727e6815144a0
git.kernel.org/...c/d21e8a2af4869b5890b34e081d5aeadc93e9cd5c
git.kernel.org/...c/3dc20d1981d6a67d8184498a5da272942dde1e65
git.kernel.org/...c/51f6532790b74ffdd6970bc848358a2838c1c185