0781168e23
In yam_ioctl(), the concrete ioctl command is firstly copied from the user-space buffer 'ifr->ifr_data' to 'ioctl_cmd' and checked through the following switch statement. If the command is not as expected, an error code EINVAL is returned. In the following execution the buffer 'ifr->ifr_data' is copied again in the cases of the switch statement to specific data structures according to what kind of ioctl command is requested. However, after the second copy, no re-check is enforced on the newly-copied command. Given that the buffer 'ifr->ifr_data' is in the user space, a malicious user can race to change the command between the two copies. This way, the attacker can inject inconsistent data and cause undefined behavior. This patch adds a re-check in each case of the switch statement if there is a second copy in that case, to re-check whether the command obtained in the second copy is the same as the one in the first copy. If not, an error code EINVAL will be returned. Signed-off-by: Wenwen Wang <wang6495@umn.edu> Signed-off-by: David S. Miller <davem@davemloft.net> |
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| .. | ||
| 6pack.c | ||
| Kconfig | ||
| Makefile | ||
| baycom_epp.c | ||
| baycom_par.c | ||
| baycom_ser_fdx.c | ||
| baycom_ser_hdx.c | ||
| bpqether.c | ||
| dmascc.c | ||
| hdlcdrv.c | ||
| mkiss.c | ||
| scc.c | ||
| yam.c | ||
| z8530.h | ||