From 90926f0e58dcd9f4ca877961000568a3be787f2f Mon Sep 17 00:00:00 2001 From: Jan Kiszka Date: Mon, 8 Feb 2010 10:12:06 +0000 Subject: [PATCH] CAPI: Sanitize capifs API Instead of looking up the dentry of an NCCI node again in capifs_free_ncci pass the pointer via the capifs user. This patch also reduces the #ifdef mess in capi.c a bit as far as capifs was causing it. Signed-off-by: Jan Kiszka Signed-off-by: David S. Miller --- drivers/isdn/capi/capi.c | 14 +++++------ drivers/isdn/capi/capifs.c | 48 ++++++++++++++++++++++---------------- drivers/isdn/capi/capifs.h | 21 +++++++++++++++-- 3 files changed, 53 insertions(+), 30 deletions(-) diff --git a/drivers/isdn/capi/capi.c b/drivers/isdn/capi/capi.c index 79f9364aded6..dc5ac52986ee 100644 --- a/drivers/isdn/capi/capi.c +++ b/drivers/isdn/capi/capi.c @@ -42,9 +42,8 @@ #include #include #include -#if defined(CONFIG_ISDN_CAPI_CAPIFS) || defined(CONFIG_ISDN_CAPI_CAPIFS_MODULE) + #include "capifs.h" -#endif static char *revision = "$Revision: 1.1.2.7 $"; @@ -96,6 +95,7 @@ struct capiminor { struct list_head list; struct capincci *nccip; unsigned int minor; + struct dentry *capifs_dentry; struct capi20_appl *ap; u32 ncci; @@ -328,9 +328,9 @@ static struct capincci *capincci_alloc(struct capidev *cdev, u32 ncci) #ifdef _DEBUG_REFCOUNT printk(KERN_DEBUG "set mp->nccip\n"); #endif -#if defined(CONFIG_ISDN_CAPI_CAPIFS) || defined(CONFIG_ISDN_CAPI_CAPIFS_MODULE) - capifs_new_ncci(mp->minor, MKDEV(capi_ttymajor, mp->minor)); -#endif + mp->capifs_dentry = + capifs_new_ncci(mp->minor, + MKDEV(capi_ttymajor, mp->minor)); } #endif /* CONFIG_ISDN_CAPI_MIDDLEWARE */ for (pp=&cdev->nccis; *pp; pp = &(*pp)->next) @@ -353,9 +353,7 @@ static void capincci_free(struct capidev *cdev, u32 ncci) *pp = (*pp)->next; #ifdef CONFIG_ISDN_CAPI_MIDDLEWARE if ((mp = np->minorp) != NULL) { -#if defined(CONFIG_ISDN_CAPI_CAPIFS) || defined(CONFIG_ISDN_CAPI_CAPIFS_MODULE) - capifs_free_ncci(mp->minor); -#endif + capifs_free_ncci(mp->capifs_dentry); if (mp->tty) { mp->nccip = NULL; #ifdef _DEBUG_REFCOUNT diff --git a/drivers/isdn/capi/capifs.c b/drivers/isdn/capi/capifs.c index dc68fcb122a0..91aafadd413f 100644 --- a/drivers/isdn/capi/capifs.c +++ b/drivers/isdn/capi/capifs.c @@ -141,31 +141,32 @@ static struct file_system_type capifs_fs_type = { .kill_sb = kill_anon_super, }; -static struct dentry *get_node(int num) -{ - char s[10]; - struct dentry *root = capifs_root; - mutex_lock(&root->d_inode->i_mutex); - return lookup_one_len(s, root, sprintf(s, "%d", num)); -} - -void capifs_new_ncci(unsigned int number, dev_t device) +struct dentry *capifs_new_ncci(unsigned int number, dev_t device) { struct dentry *dentry; struct inode *inode; + char name[10]; + int namelen; - dentry = get_node(number); - if (IS_ERR(dentry)) + mutex_lock(&capifs_root->d_inode->i_mutex); + + namelen = sprintf(name, "%d", number); + dentry = lookup_one_len(name, capifs_root, namelen); + if (IS_ERR(dentry)) { + dentry = NULL; goto unlock_out; + } if (dentry->d_inode) { dput(dentry); + dentry = NULL; goto unlock_out; } inode = new_inode(capifs_mnt->mnt_sb); if (!inode) { dput(dentry); + dentry = NULL; goto unlock_out; } @@ -177,24 +178,31 @@ void capifs_new_ncci(unsigned int number, dev_t device) init_special_inode(inode, S_IFCHR|config.mode, device); d_instantiate(dentry, inode); + dget(dentry); unlock_out: mutex_unlock(&capifs_root->d_inode->i_mutex); + + return dentry; } -void capifs_free_ncci(unsigned int number) +void capifs_free_ncci(struct dentry *dentry) { - struct dentry *dentry = get_node(number); + struct inode *inode; - if (!IS_ERR(dentry)) { - struct inode *inode = dentry->d_inode; - if (inode) { - inode->i_nlink--; - d_delete(dentry); - dput(dentry); - } + if (!dentry) + return; + + mutex_lock(&capifs_root->d_inode->i_mutex); + + inode = dentry->d_inode; + if (inode) { + drop_nlink(inode); + d_delete(dentry); dput(dentry); } + dput(dentry); + mutex_unlock(&capifs_root->d_inode->i_mutex); } diff --git a/drivers/isdn/capi/capifs.h b/drivers/isdn/capi/capifs.h index d0bd4c3c430a..e193d1189531 100644 --- a/drivers/isdn/capi/capifs.h +++ b/drivers/isdn/capi/capifs.h @@ -7,5 +7,22 @@ * */ -void capifs_new_ncci(unsigned int num, dev_t device); -void capifs_free_ncci(unsigned int num); +#include + +#if defined(CONFIG_ISDN_CAPI_CAPIFS) || defined(CONFIG_ISDN_CAPI_CAPIFS_MODULE) + +struct dentry *capifs_new_ncci(unsigned int num, dev_t device); +void capifs_free_ncci(struct dentry *dentry); + +#else + +static inline struct dentry *capifs_new_ncci(unsigned int num, dev_t device) +{ + return NULL; +} + +static inline void capifs_free_ncci(struct dentry *dentry) +{ +} + +#endif