In case debugfs does not init for some reason (or is disabled
on older kernels) driver does not allocate stats.fw_stats
structure, but tries to clear it later and trips on a NULL
pointer:
Unable to handle kernel NULL pointer dereference at virtual address
00000000
PC is at __memzero+0x24/0x80
Backtrace:
[<
bf0ddb88>] (wl1251_debugfs_reset+0x0/0x30 [wl1251])
[<
bf0d6a2c>] (wl1251_op_stop+0x0/0x12c [wl1251])
[<
bf0bc228>] (ieee80211_stop_device+0x0/0x74 [mac80211])
[<
bf0b0d10>] (ieee80211_stop+0x0/0x4ac [mac80211])
[<
c02deeac>] (dev_close+0x0/0xb4)
[<
c02deac0>] (dev_change_flags+0x0/0x184)
[<
c031f478>] (devinet_ioctl+0x0/0x704)
[<
c0320720>] (inet_ioctl+0x0/0x100)
Add a NULL pointer check to fix this.
Signed-off-by: Grazvydas Ignotas <notasas@gmail.com>
Acked-by: Kalle Valo <kalle.valo@iki.fi>
Cc: stable@kernel.org
Signed-off-by: John W. Linville <linville@tuxdriver.com>
void wl1251_debugfs_reset(struct wl1251 *wl)
{
- memset(wl->stats.fw_stats, 0, sizeof(*wl->stats.fw_stats));
+ if (wl->stats.fw_stats != NULL)
+ memset(wl->stats.fw_stats, 0, sizeof(*wl->stats.fw_stats));
wl->stats.retry_count = 0;
wl->stats.excessive_retries = 0;
}