mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2025-01-07 21:53:44 +00:00
19b070fefd
Syzkaller hit 'WARNING in dg_dispatch_as_host' bug. memcpy: detected field-spanning write (size 56) of single field "&dg_info->msg" at drivers/misc/vmw_vmci/vmci_datagram.c:237 (size 24) WARNING: CPU: 0 PID: 1555 at drivers/misc/vmw_vmci/vmci_datagram.c:237 dg_dispatch_as_host+0x88e/0xa60 drivers/misc/vmw_vmci/vmci_datagram.c:237 Some code commentry, based on my understanding: 544 #define VMCI_DG_SIZE(_dg) (VMCI_DG_HEADERSIZE + (size_t)(_dg)->payload_size) /// This is 24 + payload_size memcpy(&dg_info->msg, dg, dg_size); Destination = dg_info->msg ---> this is a 24 byte structure(struct vmci_datagram) Source = dg --> this is a 24 byte structure (struct vmci_datagram) Size = dg_size = 24 + payload_size {payload_size = 56-24 =32} -- Syzkaller managed to set payload_size to 32. 35 struct delayed_datagram_info { 36 struct datagram_entry *entry; 37 struct work_struct work; 38 bool in_dg_host_queue; 39 /* msg and msg_payload must be together. */ 40 struct vmci_datagram msg; 41 u8 msg_payload[]; 42 }; So those extra bytes of payload are copied into msg_payload[], a run time warning is seen while fuzzing with Syzkaller. One possible way to fix the warning is to split the memcpy() into two parts -- one -- direct assignment of msg and second taking care of payload. Gustavo quoted: "Under FORTIFY_SOURCE we should not copy data across multiple members in a structure." Reported-by: syzkaller <syzkaller@googlegroups.com> Suggested-by: Vegard Nossum <vegard.nossum@oracle.com> Suggested-by: Gustavo A. R. Silva <gustavoars@kernel.org> Signed-off-by: Harshit Mogalapalli <harshit.m.mogalapalli@oracle.com> Reviewed-by: Gustavo A. R. Silva <gustavoars@kernel.org> Reviewed-by: Kees Cook <keescook@chromium.org> Reviewed-by: Dan Carpenter <dan.carpenter@linaro.org> Link: https://lore.kernel.org/r/20240105164001.2129796-2-harshit.m.mogalapalli@oracle.com Signed-off-by: Kees Cook <keescook@chromium.org> |
||
---|---|---|
.. | ||
altera-stapl | ||
bcm-vk | ||
c2port | ||
cardreader | ||
cb710 | ||
cxl | ||
echo | ||
eeprom | ||
genwqe | ||
ibmasm | ||
lis3lv02d | ||
lkdtm | ||
mchp_pci1xxxx | ||
mei | ||
ocxl | ||
pvpanic | ||
sgi-gru | ||
sgi-xp | ||
ti-st | ||
uacce | ||
vmw_vmci | ||
ad525x_dpot-i2c.c | ||
ad525x_dpot-spi.c | ||
ad525x_dpot.c | ||
ad525x_dpot.h | ||
apds990x.c | ||
apds9802als.c | ||
atmel-ssc.c | ||
bh1770glc.c | ||
cs5535-mfgpt.c | ||
ds1682.c | ||
dummy-irq.c | ||
dw-xdata-pcie.c | ||
enclosure.c | ||
fastrpc.c | ||
gehc-achc.c | ||
hi6421v600-irq.c | ||
hisi_hikey_usb.c | ||
hmc6352.c | ||
hpilo.c | ||
hpilo.h | ||
ibmvmc.c | ||
ibmvmc.h | ||
ics932s401.c | ||
isl29003.c | ||
isl29020.c | ||
Kconfig | ||
kgdbts.c | ||
lattice-ecp3-config.c | ||
Makefile | ||
nsm.c | ||
open-dice.c | ||
pch_phub.c | ||
pci_endpoint_test.c | ||
phantom.c | ||
qcom-coincell.c | ||
smpro-errmon.c | ||
smpro-misc.c | ||
sram-exec.c | ||
sram.c | ||
sram.h | ||
tifm_7xx1.c | ||
tifm_core.c | ||
tps6594-esm.c | ||
tps6594-pfsm.c | ||
tsl2550.c | ||
vcpu_stall_detector.c | ||
vmw_balloon.c | ||
xilinx_sdfec.c | ||
xilinx_tmr_inject.c | ||
xilinx_tmr_manager.c |