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author | Jouni Hogander <jouni.hogander@unikie.com> | 2019-11-25 15:23:43 +0300 |
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committer | David S. Miller <davem@davemloft.net> | 2019-11-25 22:02:52 +0300 |
commit | e58c1912418980f57ba2060017583067f5f71e52 (patch) | |
tree | d5e801095e709d00fa37917c03d1b2a2f7630c05 /drivers/net/slip | |
parent | 9bca3a0a923fc3f0fb9e41391be1d0f291e86858 (diff) | |
download | linux-e58c1912418980f57ba2060017583067f5f71e52.tar.xz |
slip: Fix use-after-free Read in slip_open
Slip_open doesn't clean-up device which registration failed from the
slip_devs device list. On next open after failure this list is iterated
and freed device is accessed. Fix this by calling sl_free_netdev in error
path.
Here is the trace from the Syzbot:
__dump_stack lib/dump_stack.c:77 [inline]
dump_stack+0x197/0x210 lib/dump_stack.c:118
print_address_description.constprop.0.cold+0xd4/0x30b mm/kasan/report.c:374
__kasan_report.cold+0x1b/0x41 mm/kasan/report.c:506
kasan_report+0x12/0x20 mm/kasan/common.c:634
__asan_report_load8_noabort+0x14/0x20 mm/kasan/generic_report.c:132
sl_sync drivers/net/slip/slip.c:725 [inline]
slip_open+0xecd/0x11b7 drivers/net/slip/slip.c:801
tty_ldisc_open.isra.0+0xa3/0x110 drivers/tty/tty_ldisc.c:469
tty_set_ldisc+0x30e/0x6b0 drivers/tty/tty_ldisc.c:596
tiocsetd drivers/tty/tty_io.c:2334 [inline]
tty_ioctl+0xe8d/0x14f0 drivers/tty/tty_io.c:2594
vfs_ioctl fs/ioctl.c:46 [inline]
file_ioctl fs/ioctl.c:509 [inline]
do_vfs_ioctl+0xdb6/0x13e0 fs/ioctl.c:696
ksys_ioctl+0xab/0xd0 fs/ioctl.c:713
__do_sys_ioctl fs/ioctl.c:720 [inline]
__se_sys_ioctl fs/ioctl.c:718 [inline]
__x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:718
do_syscall_64+0xfa/0x760 arch/x86/entry/common.c:290
entry_SYSCALL_64_after_hwframe+0x49/0xbe
Fixes: 3b5a39979daf ("slip: Fix memory leak in slip_open error path")
Reported-by: syzbot+4d5170758f3762109542@syzkaller.appspotmail.com
Cc: David Miller <davem@davemloft.net>
Cc: Oliver Hartkopp <socketcan@hartkopp.net>
Cc: Lukas Bulwahn <lukas.bulwahn@gmail.com>
Signed-off-by: Jouni Hogander <jouni.hogander@unikie.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'drivers/net/slip')
-rw-r--r-- | drivers/net/slip/slip.c | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/drivers/net/slip/slip.c b/drivers/net/slip/slip.c index 4d479e3c817d..2a91c192659f 100644 --- a/drivers/net/slip/slip.c +++ b/drivers/net/slip/slip.c @@ -855,6 +855,7 @@ err_free_chan: sl->tty = NULL; tty->disc_data = NULL; clear_bit(SLF_INUSE, &sl->flags); + sl_free_netdev(sl->dev); free_netdev(sl->dev); err_exit: |