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| author | Duoming Zhou <duoming@zju.edu.cn> | 2022-02-03 23:08:11 +0800 |
|---|---|---|
| committer | Jakub Kicinski <kuba@kernel.org> | 2022-02-03 14:20:36 -0800 |
| commit | 87563a043cef044fed5db7967a75741cc16ad2b1 (patch) | |
| tree | 4afe345736b9d1e946ddd4ad5fdbc349b046900f /net/ax25/af_ax25.c | |
| parent | 80d4609008e6d696a279e39ae7458c916fcd44c1 (diff) | |
| download | linux-87563a043cef044fed5db7967a75741cc16ad2b1.tar.bz2 | |
ax25: fix reference count leaks of ax25_dev
The previous commit d01ffb9eee4a ("ax25: add refcount in ax25_dev
to avoid UAF bugs") introduces refcount into ax25_dev, but there
are reference leak paths in ax25_ctl_ioctl(), ax25_fwd_ioctl(),
ax25_rt_add(), ax25_rt_del() and ax25_rt_opt().
This patch uses ax25_dev_put() and adjusts the position of
ax25_addr_ax25dev() to fix reference cout leaks of ax25_dev.
Fixes: d01ffb9eee4a ("ax25: add refcount in ax25_dev to avoid UAF bugs")
Signed-off-by: Duoming Zhou <duoming@zju.edu.cn>
Reviewed-by: Dan Carpenter <dan.carpenter@oracle.com>
Link: https://lore.kernel.org/r/20220203150811.42256-1-duoming@zju.edu.cn
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Diffstat (limited to 'net/ax25/af_ax25.c')
| -rw-r--r-- | net/ax25/af_ax25.c | 12 |
1 files changed, 8 insertions, 4 deletions
diff --git a/net/ax25/af_ax25.c b/net/ax25/af_ax25.c index 32f61978ff29..3e49d28824ed 100644 --- a/net/ax25/af_ax25.c +++ b/net/ax25/af_ax25.c @@ -359,21 +359,25 @@ static int ax25_ctl_ioctl(const unsigned int cmd, void __user *arg) if (copy_from_user(&ax25_ctl, arg, sizeof(ax25_ctl))) return -EFAULT; - if ((ax25_dev = ax25_addr_ax25dev(&ax25_ctl.port_addr)) == NULL) - return -ENODEV; - if (ax25_ctl.digi_count > AX25_MAX_DIGIS) return -EINVAL; if (ax25_ctl.arg > ULONG_MAX / HZ && ax25_ctl.cmd != AX25_KILL) return -EINVAL; + ax25_dev = ax25_addr_ax25dev(&ax25_ctl.port_addr); + if (!ax25_dev) + return -ENODEV; + digi.ndigi = ax25_ctl.digi_count; for (k = 0; k < digi.ndigi; k++) digi.calls[k] = ax25_ctl.digi_addr[k]; - if ((ax25 = ax25_find_cb(&ax25_ctl.source_addr, &ax25_ctl.dest_addr, &digi, ax25_dev->dev)) == NULL) + ax25 = ax25_find_cb(&ax25_ctl.source_addr, &ax25_ctl.dest_addr, &digi, ax25_dev->dev); + if (!ax25) { + ax25_dev_put(ax25_dev); return -ENOTCONN; + } switch (ax25_ctl.cmd) { case AX25_KILL: |