From 94543a8d4fb302817014981489f15cb3b92ec3c2 Mon Sep 17 00:00:00 2001 From: Johannes Berg Date: Tue, 21 Aug 2012 18:57:10 +0200 Subject: [PATCH] iwlwifi: fix flow handler debug code iwl_dbgfs_fh_reg_read() can cause crashes and/or BUG_ON in slub because the ifdefs are wrong, the code in iwl_dump_fh() should use DEBUGFS, not DEBUG to protect the buffer writing code. Also, while at it, clean up the arguments to the function, some code and make it generally safer. Cc: stable@vger.kernel.org Reported-by: Benjamin Herrenschmidt Signed-off-by: Johannes Berg Signed-off-by: John W. Linville --- drivers/net/wireless/iwlwifi/pcie/internal.h | 2 +- drivers/net/wireless/iwlwifi/pcie/rx.c | 2 +- drivers/net/wireless/iwlwifi/pcie/trans.c | 30 +++++++++++--------- 3 files changed, 18 insertions(+), 16 deletions(-) diff --git a/drivers/net/wireless/iwlwifi/pcie/internal.h b/drivers/net/wireless/iwlwifi/pcie/internal.h index d9694c58208c..4ffc18dc3a57 100644 --- a/drivers/net/wireless/iwlwifi/pcie/internal.h +++ b/drivers/net/wireless/iwlwifi/pcie/internal.h @@ -350,7 +350,7 @@ int iwl_queue_space(const struct iwl_queue *q); /***************************************************** * Error handling ******************************************************/ -int iwl_dump_fh(struct iwl_trans *trans, char **buf, bool display); +int iwl_dump_fh(struct iwl_trans *trans, char **buf); void iwl_dump_csr(struct iwl_trans *trans); /***************************************************** diff --git a/drivers/net/wireless/iwlwifi/pcie/rx.c b/drivers/net/wireless/iwlwifi/pcie/rx.c index 39a6ca1f009c..d1a61ba6247a 100644 --- a/drivers/net/wireless/iwlwifi/pcie/rx.c +++ b/drivers/net/wireless/iwlwifi/pcie/rx.c @@ -555,7 +555,7 @@ static void iwl_irq_handle_error(struct iwl_trans *trans) } iwl_dump_csr(trans); - iwl_dump_fh(trans, NULL, false); + iwl_dump_fh(trans, NULL); iwl_op_mode_nic_error(trans->op_mode); } diff --git a/drivers/net/wireless/iwlwifi/pcie/trans.c b/drivers/net/wireless/iwlwifi/pcie/trans.c index 939c2f78df58..1e86ea2266d4 100644 --- a/drivers/net/wireless/iwlwifi/pcie/trans.c +++ b/drivers/net/wireless/iwlwifi/pcie/trans.c @@ -1649,13 +1649,9 @@ static const char *get_fh_string(int cmd) #undef IWL_CMD } -int iwl_dump_fh(struct iwl_trans *trans, char **buf, bool display) +int iwl_dump_fh(struct iwl_trans *trans, char **buf) { int i; -#ifdef CONFIG_IWLWIFI_DEBUG - int pos = 0; - size_t bufsz = 0; -#endif static const u32 fh_tbl[] = { FH_RSCSR_CHNL0_STTS_WPTR_REG, FH_RSCSR_CHNL0_RBDCB_BASE_REG, @@ -1667,29 +1663,35 @@ int iwl_dump_fh(struct iwl_trans *trans, char **buf, bool display) FH_TSSR_TX_STATUS_REG, FH_TSSR_TX_ERROR_REG }; -#ifdef CONFIG_IWLWIFI_DEBUG - if (display) { - bufsz = ARRAY_SIZE(fh_tbl) * 48 + 40; + +#ifdef CONFIG_IWLWIFI_DEBUGFS + if (buf) { + int pos = 0; + size_t bufsz = ARRAY_SIZE(fh_tbl) * 48 + 40; + *buf = kmalloc(bufsz, GFP_KERNEL); if (!*buf) return -ENOMEM; + pos += scnprintf(*buf + pos, bufsz - pos, "FH register values:\n"); - for (i = 0; i < ARRAY_SIZE(fh_tbl); i++) { + + for (i = 0; i < ARRAY_SIZE(fh_tbl); i++) pos += scnprintf(*buf + pos, bufsz - pos, " %34s: 0X%08x\n", get_fh_string(fh_tbl[i]), iwl_read_direct32(trans, fh_tbl[i])); - } + return pos; } #endif + IWL_ERR(trans, "FH register values:\n"); - for (i = 0; i < ARRAY_SIZE(fh_tbl); i++) { + for (i = 0; i < ARRAY_SIZE(fh_tbl); i++) IWL_ERR(trans, " %34s: 0X%08x\n", get_fh_string(fh_tbl[i]), iwl_read_direct32(trans, fh_tbl[i])); - } + return 0; } @@ -1982,11 +1984,11 @@ static ssize_t iwl_dbgfs_fh_reg_read(struct file *file, size_t count, loff_t *ppos) { struct iwl_trans *trans = file->private_data; - char *buf; + char *buf = NULL; int pos = 0; ssize_t ret = -EFAULT; - ret = pos = iwl_dump_fh(trans, &buf, true); + ret = pos = iwl_dump_fh(trans, &buf); if (buf) { ret = simple_read_from_buffer(user_buf, count, ppos, buf, pos); -- 2.30.2