There is a specific error path in probe functions in wilc drivers (both
sdio and spi) which can lead to kernel panic, as this one for example
when using SPI:
Unable to handle kernel paging request at virtual address 9f000000 when read
[9f000000] *pgd=00000000
Internal error: Oops: 5 [#1] ARM
Modules linked in: wilc1000_spi(+) crc_itu_t crc7 wilc1000 cfg80211 bluetooth ecdh_generic ecc
CPU: 0 UID: 0 PID: 106 Comm: modprobe Not tainted 6.13.0-rc3+ #22
Hardware name: Atmel SAMA5
PC is at wiphy_unregister+0x244/0xc40 [cfg80211]
LR is at wiphy_unregister+0x1c0/0xc40 [cfg80211]
[...]
wiphy_unregister [cfg80211] from wilc_netdev_cleanup+0x380/0x494 [wilc1000]
wilc_netdev_cleanup [wilc1000] from wilc_bus_probe+0x360/0x834 [wilc1000_spi]
wilc_bus_probe [wilc1000_spi] from spi_probe+0x15c/0x1d4
spi_probe from really_probe+0x270/0xb2c
really_probe from __driver_probe_device+0x1dc/0x4e8
__driver_probe_device from driver_probe_device+0x5c/0x140
driver_probe_device from __driver_attach+0x220/0x540
__driver_attach from bus_for_each_dev+0x13c/0x1a8
bus_for_each_dev from bus_add_driver+0x2a0/0x6a4
bus_add_driver from driver_register+0x27c/0x51c
driver_register from do_one_initcall+0xf8/0x564
do_one_initcall from do_init_module+0x2e4/0x82c
do_init_module from load_module+0x59a0/0x70c4
load_module from init_module_from_file+0x100/0x148
init_module_from_file from sys_finit_module+0x2fc/0x924
sys_finit_module from ret_fast_syscall+0x0/0x1c
The issue can easily be reproduced, for example by not wiring correctly
a wilc device through SPI (and so, make it unresponsive to early SPI
commands). It is due to a recent change decoupling wiphy allocation from
wiphy registration, however wilc_netdev_cleanup has not been updated
accordingly, letting it possibly call wiphy unregister on a wiphy which
has never been registered.
Fix this crash by moving wiphy_unregister/wiphy_free out of
wilc_netdev_cleanup, and by adjusting error paths in both drivers
Fixes: fbdf0c5248dc ("wifi: wilc1000: Register wiphy after reading out chipid")
Signed-off-by: Alexis Lothoré <alexis.lothore@xxxxxxxxxxx>
---
drivers/net/wireless/microchip/wilc1000/netdev.c | 2 --
drivers/net/wireless/microchip/wilc1000/sdio.c | 9 +++++++--
drivers/net/wireless/microchip/wilc1000/spi.c | 9 +++++++--
3 files changed, 14 insertions(+), 6 deletions(-)
diff --git a/drivers/net/wireless/microchip/wilc1000/netdev.c b/drivers/net/wireless/microchip/wilc1000/netdev.c
index 7e84fc0fd91188b411863b9de647b6d182c6c187..af298021e05041ba4b16a94c8ee768407a208dfc 100644
--- a/drivers/net/wireless/microchip/wilc1000/netdev.c
+++ b/drivers/net/wireless/microchip/wilc1000/netdev.c
@@ -925,8 +925,6 @@ void wilc_netdev_cleanup(struct wilc *wilc)
wilc_wlan_cfg_deinit(wilc);
wlan_deinit_locks(wilc);
- wiphy_unregister(wilc->wiphy);
- wiphy_free(wilc->wiphy);
}
EXPORT_SYMBOL_GPL(wilc_netdev_cleanup);
diff --git a/drivers/net/wireless/microchip/wilc1000/sdio.c b/drivers/net/wireless/microchip/wilc1000/sdio.c
index 5262c8846c13df28cf65ec8c5ad0ef9d6677c98b..3751e2ee1ca95918b589ba9be032984705fa822a 100644
--- a/drivers/net/wireless/microchip/wilc1000/sdio.c
+++ b/drivers/net/wireless/microchip/wilc1000/sdio.c
@@ -193,7 +193,7 @@ static int wilc_sdio_probe(struct sdio_func *func,
ret = wilc_load_mac_from_nv(wilc);
if (ret) {
pr_err("Can not retrieve MAC address from chip\n");
- goto dispose_irq;
+ goto unregister_wiphy;
}
wilc_sdio_deinit(wilc);
@@ -202,15 +202,18 @@ static int wilc_sdio_probe(struct sdio_func *func,
NL80211_IFTYPE_STATION, false);
if (IS_ERR(vif)) {
ret = PTR_ERR(vif);
- goto dispose_irq;
+ goto unregister_wiphy;
}
dev_info(&func->dev, "Driver Initializing success\n");
return 0;
+unregister_wiphy:
+ wiphy_unregister(wilc->wiphy);
dispose_irq:
irq_dispose_mapping(wilc->dev_irq_num);
wilc_netdev_cleanup(wilc);
+ wiphy_free(wilc->wiphy);
free:
kfree(sdio_priv->cmd53_buf);
kfree(sdio_priv);
@@ -222,7 +225,9 @@ static void wilc_sdio_remove(struct sdio_func *func)
struct wilc *wilc = sdio_get_drvdata(func);
struct wilc_sdio *sdio_priv = wilc->bus_data;
+ wiphy_unregister(wilc->wiphy);
wilc_netdev_cleanup(wilc);
+ wiphy_free(wilc->wiphy);
kfree(sdio_priv->cmd53_buf);
kfree(sdio_priv);
}
diff --git a/drivers/net/wireless/microchip/wilc1000/spi.c b/drivers/net/wireless/microchip/wilc1000/spi.c
index ce2a9cdd6aa7877ed4c2517f9549a00bdc8dc874..31219fd0cfb3fc6df071b3e9be5af17087ccf583 100644
--- a/drivers/net/wireless/microchip/wilc1000/spi.c
+++ b/drivers/net/wireless/microchip/wilc1000/spi.c
@@ -256,7 +256,7 @@ static int wilc_bus_probe(struct spi_device *spi)
ret = wilc_load_mac_from_nv(wilc);
if (ret) {
pr_err("Can not retrieve MAC address from chip\n");
- goto power_down;
+ goto unregister_wiphy;
}
wilc_wlan_power(wilc, false);
@@ -264,14 +264,17 @@ static int wilc_bus_probe(struct spi_device *spi)
NL80211_IFTYPE_STATION, false);
if (IS_ERR(vif)) {
ret = PTR_ERR(vif);
- goto power_down;
+ goto unregister_wiphy;
}
return 0;
+unregister_wiphy:
+ wiphy_unregister(wilc->wiphy);
power_down:
wilc_wlan_power(wilc, false);
netdev_cleanup:
wilc_netdev_cleanup(wilc);
+ wiphy_free(wilc->wiphy);
free:
kfree(spi_priv);
return ret;
@@ -282,7 +285,9 @@ static void wilc_bus_remove(struct spi_device *spi)
struct wilc *wilc = spi_get_drvdata(spi);
struct wilc_spi *spi_priv = wilc->bus_data;
+ wiphy_unregister(wilc->wiphy);
wilc_netdev_cleanup(wilc);
+ wiphy_free(wilc->wiphy);
kfree(spi_priv);
}
---
base-commit: 96997ddfc7c249dbcb6e248986dc2d56ba29ec8b
change-id: 20241223-wilc_fix_probe_error_path-a64be3a9b39a
Best regards,
--
Alexis Lothoré, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com
