param: simple locking for sysfs-writable charp parameters Since the writing to sysfs can free the old one, we need to block that when we access. Signed-off-by: Rusty Russell Reviewed-by: Takashi Iwai --- arch/um/drivers/hostaudio_kern.c | 10 ++++++++++ drivers/net/wireless/libertas/if_usb.c | 3 +++ drivers/net/wireless/libertas_tf/if_usb.c | 3 +++ drivers/scsi/bfa/bfad.c | 2 ++ drivers/usb/atm/ueagle-atm.c | 2 ++ drivers/video/vt8623fb.c | 2 ++ net/mac80211/rate.c | 2 ++ 7 files changed, 24 insertions(+) diff --git a/arch/um/drivers/hostaudio_kern.c b/arch/um/drivers/hostaudio_kern.c --- a/arch/um/drivers/hostaudio_kern.c +++ b/arch/um/drivers/hostaudio_kern.c @@ -186,7 +186,9 @@ static int hostaudio_open(struct inode * int ret; #ifdef DEBUG + kparam_block_sysfs_write(dsp); printk(KERN_DEBUG "hostaudio: open called (host: %s)\n", dsp); + kparam_unblock_sysfs_write(dsp); #endif state = kmalloc(sizeof(struct hostaudio_state), GFP_KERNEL); @@ -198,7 +200,9 @@ static int hostaudio_open(struct inode * if (file->f_mode & FMODE_WRITE) w = 1; + kparam_block_sysfs_write(dsp); ret = os_open_file(dsp, of_set_rw(OPENFLAGS(), r, w), 0); + kparam_unblock_sysfs_write(dsp); if (ret < 0) { kfree(state); return ret; @@ -254,11 +258,15 @@ static int hostmixer_open_mixdev(struct if (file->f_mode & FMODE_WRITE) w = 1; + kparam_block_sysfs_write(mixer); ret = os_open_file(mixer, of_set_rw(OPENFLAGS(), r, w), 0); + kparam_unblock_sysfs_write(mixer); if (ret < 0) { + kparam_block_sysfs_write(dsp); printk(KERN_ERR "hostaudio_open_mixdev failed to open '%s', " "err = %d\n", dsp, -ret); + kparam_unblock_sysfs_write(dsp); kfree(state); return ret; } @@ -314,8 +322,10 @@ MODULE_LICENSE("GPL"); static int __init hostaudio_init_module(void) { + __kernel_param_lock(); printk(KERN_INFO "UML Audio Relay (host dsp = %s, host mixer = %s)\n", dsp, mixer); + __kernel_param_unlock(); module_data.dev_audio = register_sound_dsp(&hostaudio_fops, -1); if (module_data.dev_audio < 0) { diff --git a/drivers/net/wireless/libertas/if_usb.c b/drivers/net/wireless/libertas/if_usb.c --- a/drivers/net/wireless/libertas/if_usb.c +++ b/drivers/net/wireless/libertas/if_usb.c @@ -288,10 +288,13 @@ static int if_usb_probe(struct usb_inter } /* Upload firmware */ + kparam_block_sysfs_write(fw_name); if (__if_usb_prog_firmware(cardp, lbs_fw_name, BOOT_CMD_FW_BY_USB)) { + kparam_unblock_sysfs_write(fw_name); lbs_deb_usbd(&udev->dev, "FW upload failed\n"); goto err_prog_firmware; } + kparam_unblock_sysfs_write(fw_name); if (!(priv = lbs_add_card(cardp, &udev->dev))) goto err_prog_firmware; diff --git a/drivers/net/wireless/libertas_tf/if_usb.c b/drivers/net/wireless/libertas_tf/if_usb.c --- a/drivers/net/wireless/libertas_tf/if_usb.c +++ b/drivers/net/wireless/libertas_tf/if_usb.c @@ -648,12 +648,15 @@ static int if_usb_prog_firmware(struct i static int reset_count = 10; int ret = 0; + kparam_block_sysfs_write(fw_name); ret = request_firmware(&cardp->fw, lbtf_fw_name, &cardp->udev->dev); if (ret < 0) { printk(KERN_INFO "libertastf: firmware %s not found\n", lbtf_fw_name); + kparam_unblock_sysfs_write(fw_name); goto done; } + kparam_unblock_sysfs_write(fw_name); if (check_fwfile_format(cardp->fw->data, cardp->fw->size)) goto release_fw; diff --git a/drivers/scsi/bfa/bfad.c b/drivers/scsi/bfa/bfad.c --- a/drivers/scsi/bfa/bfad.c +++ b/drivers/scsi/bfa/bfad.c @@ -726,6 +726,7 @@ bfad_drv_init(struct bfad_s *bfad) memset(&driver_info, 0, sizeof(driver_info)); strncpy(driver_info.version, BFAD_DRIVER_VERSION, sizeof(driver_info.version) - 1); + __kernel_param_lock(); if (host_name) strncpy(driver_info.host_machine_name, host_name, sizeof(driver_info.host_machine_name) - 1); @@ -735,6 +736,7 @@ bfad_drv_init(struct bfad_s *bfad) if (os_patch) strncpy(driver_info.host_os_patch, os_patch, sizeof(driver_info.host_os_patch) - 1); + __kernel_param_unlock(); strncpy(driver_info.os_device_name, bfad->pci_name, sizeof(driver_info.os_device_name - 1)); diff --git a/drivers/usb/atm/ueagle-atm.c b/drivers/usb/atm/ueagle-atm.c --- a/drivers/usb/atm/ueagle-atm.c +++ b/drivers/usb/atm/ueagle-atm.c @@ -1550,6 +1550,7 @@ static void cmvs_file_name(struct uea_so char file_arr[] = "CMVxy.bin"; char *file; + kparam_block_sysfs_write(cmv_file); /* set proper name corresponding modem version and line type */ if (cmv_file[sc->modem_index] == NULL) { if (UEA_CHIP_VERSION(sc) == ADI930) @@ -1568,6 +1569,7 @@ static void cmvs_file_name(struct uea_so strlcat(cmv_name, file, UEA_FW_NAME_MAX); if (ver == 2) strlcat(cmv_name, ".v2", UEA_FW_NAME_MAX); + kparam_unblock_sysfs_write(cmv_file); } static int request_cmvs_old(struct uea_softc *sc, diff --git a/net/mac80211/rate.c b/net/mac80211/rate.c --- a/net/mac80211/rate.c +++ b/net/mac80211/rate.c @@ -102,6 +102,7 @@ ieee80211_rate_control_ops_get(const cha struct rate_control_ops *ops; const char *alg_name; + kparam_block_sysfs_write(ieee80211_default_rc_algo); if (!name) alg_name = ieee80211_default_rc_algo; else @@ -119,6 +120,7 @@ ieee80211_rate_control_ops_get(const cha /* try built-in one if specific alg requested but not found */ if (!ops && strlen(CONFIG_MAC80211_RC_DEFAULT)) ops = ieee80211_try_rate_control_ops_get(CONFIG_MAC80211_RC_DEFAULT); + kparam_unblock_sysfs_write(ieee80211_default_rc_algo); return ops; } diff --git a/drivers/video/vt8623fb.c b/drivers/video/vt8623fb.c --- a/drivers/video/vt8623fb.c +++ b/drivers/video/vt8623fb.c @@ -727,7 +727,9 @@ static int __devinit vt8623_pci_probe(st /* Prepare startup mode */ + kparam_block_sysfs_write(mode_option); rc = fb_find_mode(&(info->var), info, mode_option, NULL, 0, NULL, 8); + kparam_unblock_sysfs_write(mode_option); if (! ((rc == 1) || (rc == 2))) { rc = -EINVAL; dev_err(info->device, "mode %s not found\n", mode_option);