mirror of https://github.com/torvalds/linux.git
hci_le_big_create_sync() uses DEFINE_FLEX to allocate a
struct hci_cp_le_big_create_sync on the stack with room for 0x11 (17)
BIS entries. However, conn->num_bis can hold up to HCI_MAX_ISO_BIS (31)
entries — validated against ISO_MAX_NUM_BIS (0x1f) in the caller
hci_conn_big_create_sync(). When conn->num_bis is between 18 and 31,
the memcpy that copies conn->bis into cp->bis writes up to 14 bytes
past the stack buffer, corrupting adjacent stack memory.
This is trivially reproducible: binding an ISO socket with
bc_num_bis = ISO_MAX_NUM_BIS (31) and calling listen() will
eventually trigger hci_le_big_create_sync() from the HCI command
sync worker, causing a KASAN-detectable stack-out-of-bounds write:
BUG: KASAN: stack-out-of-bounds in hci_le_big_create_sync+0x256/0x3b0
Write of size 31 at addr ffffc90000487b48 by task kworker/u9:0/71
Fix this by changing the DEFINE_FLEX count from the incorrect 0x11 to
HCI_MAX_ISO_BIS, which matches the maximum number of BIS entries that
conn->bis can actually carry.
Fixes:
|
||
|---|---|---|
| .. | ||
| bnep | ||
| cmtp | ||
| hidp | ||
| rfcomm | ||
| 6lowpan.c | ||
| Kconfig | ||
| Makefile | ||
| af_bluetooth.c | ||
| aosp.c | ||
| aosp.h | ||
| coredump.c | ||
| ecdh_helper.c | ||
| ecdh_helper.h | ||
| eir.c | ||
| eir.h | ||
| hci_codec.c | ||
| hci_codec.h | ||
| hci_conn.c | ||
| hci_core.c | ||
| hci_debugfs.c | ||
| hci_debugfs.h | ||
| hci_drv.c | ||
| hci_event.c | ||
| hci_sock.c | ||
| hci_sync.c | ||
| hci_sysfs.c | ||
| iso.c | ||
| l2cap_core.c | ||
| l2cap_sock.c | ||
| leds.c | ||
| leds.h | ||
| lib.c | ||
| mgmt.c | ||
| mgmt_config.c | ||
| mgmt_config.h | ||
| mgmt_util.c | ||
| mgmt_util.h | ||
| msft.c | ||
| msft.h | ||
| sco.c | ||
| selftest.c | ||
| selftest.h | ||
| smp.c | ||
| smp.h | ||