From eb1a6bdc28268afa964e4c9f3399961dff9fd691 Mon Sep 17 00:00:00 2001 From: Julia Lawall Date: Fri, 11 Nov 2016 13:32:38 +0100 Subject: [PATCH] netfilter: x_tables: simplify IS_ERR_OR_NULL to NULL test Since commit 7926dbfa4bc1 ("netfilter: don't use mutex_lock_interruptible()"), the function xt_find_table_lock can only return NULL on an error. Simplify the call sites and update the comment before the function. The semantic patch that change the code is as follows: (http://coccinelle.lip6.fr/) // @@ expression t,e; @@ t = \(xt_find_table_lock(...)\| try_then_request_module(xt_find_table_lock(...),...)\) ... when != t=e - ! IS_ERR_OR_NULL(t) + t @@ expression t,e; @@ t = \(xt_find_table_lock(...)\| try_then_request_module(xt_find_table_lock(...),...)\) ... when != t=e - IS_ERR_OR_NULL(t) + !t @@ expression t,e,e1; @@ t = \(xt_find_table_lock(...)\| try_then_request_module(xt_find_table_lock(...),...)\) ... when != t=e ?- t ? PTR_ERR(t) : e1 + e1 ... when any // Signed-off-by: Julia Lawall Signed-off-by: Pablo Neira Ayuso --- net/ipv4/netfilter/arp_tables.c | 20 ++++++++++---------- net/ipv4/netfilter/ip_tables.c | 20 ++++++++++---------- net/ipv6/netfilter/ip6_tables.c | 20 ++++++++++---------- net/netfilter/x_tables.c | 2 +- 4 files changed, 31 insertions(+), 31 deletions(-) diff --git a/net/ipv4/netfilter/arp_tables.c b/net/ipv4/netfilter/arp_tables.c index e76ab23..39004da 100644 --- a/net/ipv4/netfilter/arp_tables.c +++ b/net/ipv4/netfilter/arp_tables.c @@ -805,7 +805,7 @@ static int get_info(struct net *net, void __user *user, #endif t = try_then_request_module(xt_find_table_lock(net, NFPROTO_ARP, name), "arptable_%s", name); - if (!IS_ERR_OR_NULL(t)) { + if (t) { struct arpt_getinfo info; const struct xt_table_info *private = t->private; #ifdef CONFIG_COMPAT @@ -834,7 +834,7 @@ static int get_info(struct net *net, void __user *user, xt_table_unlock(t); module_put(t->me); } else - ret = t ? PTR_ERR(t) : -ENOENT; + ret = -ENOENT; #ifdef CONFIG_COMPAT if (compat) xt_compat_unlock(NFPROTO_ARP); @@ -859,7 +859,7 @@ static int get_entries(struct net *net, struct arpt_get_entries __user *uptr, get.name[sizeof(get.name) - 1] = '\0'; t = xt_find_table_lock(net, NFPROTO_ARP, get.name); - if (!IS_ERR_OR_NULL(t)) { + if (t) { const struct xt_table_info *private = t->private; if (get.size == private->size) @@ -871,7 +871,7 @@ static int get_entries(struct net *net, struct arpt_get_entries __user *uptr, module_put(t->me); xt_table_unlock(t); } else - ret = t ? PTR_ERR(t) : -ENOENT; + ret = -ENOENT; return ret; } @@ -898,8 +898,8 @@ static int __do_replace(struct net *net, const char *name, t = try_then_request_module(xt_find_table_lock(net, NFPROTO_ARP, name), "arptable_%s", name); - if (IS_ERR_OR_NULL(t)) { - ret = t ? PTR_ERR(t) : -ENOENT; + if (!t) { + ret = -ENOENT; goto free_newinfo_counters_untrans; } @@ -1014,8 +1014,8 @@ static int do_add_counters(struct net *net, const void __user *user, return PTR_ERR(paddc); t = xt_find_table_lock(net, NFPROTO_ARP, tmp.name); - if (IS_ERR_OR_NULL(t)) { - ret = t ? PTR_ERR(t) : -ENOENT; + if (!t) { + ret = -ENOENT; goto free; } @@ -1404,7 +1404,7 @@ static int compat_get_entries(struct net *net, xt_compat_lock(NFPROTO_ARP); t = xt_find_table_lock(net, NFPROTO_ARP, get.name); - if (!IS_ERR_OR_NULL(t)) { + if (t) { const struct xt_table_info *private = t->private; struct xt_table_info info; @@ -1419,7 +1419,7 @@ static int compat_get_entries(struct net *net, module_put(t->me); xt_table_unlock(t); } else - ret = t ? PTR_ERR(t) : -ENOENT; + ret = -ENOENT; xt_compat_unlock(NFPROTO_ARP); return ret; diff --git a/net/ipv4/netfilter/ip_tables.c b/net/ipv4/netfilter/ip_tables.c index de4fa03..46815c8 100644 --- a/net/ipv4/netfilter/ip_tables.c +++ b/net/ipv4/netfilter/ip_tables.c @@ -973,7 +973,7 @@ static int get_info(struct net *net, void __user *user, #endif t = try_then_request_module(xt_find_table_lock(net, AF_INET, name), "iptable_%s", name); - if (!IS_ERR_OR_NULL(t)) { + if (t) { struct ipt_getinfo info; const struct xt_table_info *private = t->private; #ifdef CONFIG_COMPAT @@ -1003,7 +1003,7 @@ static int get_info(struct net *net, void __user *user, xt_table_unlock(t); module_put(t->me); } else - ret = t ? PTR_ERR(t) : -ENOENT; + ret = -ENOENT; #ifdef CONFIG_COMPAT if (compat) xt_compat_unlock(AF_INET); @@ -1028,7 +1028,7 @@ get_entries(struct net *net, struct ipt_get_entries __user *uptr, get.name[sizeof(get.name) - 1] = '\0'; t = xt_find_table_lock(net, AF_INET, get.name); - if (!IS_ERR_OR_NULL(t)) { + if (t) { const struct xt_table_info *private = t->private; if (get.size == private->size) ret = copy_entries_to_user(private->size, @@ -1039,7 +1039,7 @@ get_entries(struct net *net, struct ipt_get_entries __user *uptr, module_put(t->me); xt_table_unlock(t); } else - ret = t ? PTR_ERR(t) : -ENOENT; + ret = -ENOENT; return ret; } @@ -1064,8 +1064,8 @@ __do_replace(struct net *net, const char *name, unsigned int valid_hooks, t = try_then_request_module(xt_find_table_lock(net, AF_INET, name), "iptable_%s", name); - if (IS_ERR_OR_NULL(t)) { - ret = t ? PTR_ERR(t) : -ENOENT; + if (!t) { + ret = -ENOENT; goto free_newinfo_counters_untrans; } @@ -1180,8 +1180,8 @@ do_add_counters(struct net *net, const void __user *user, return PTR_ERR(paddc); t = xt_find_table_lock(net, AF_INET, tmp.name); - if (IS_ERR_OR_NULL(t)) { - ret = t ? PTR_ERR(t) : -ENOENT; + if (!t) { + ret = -ENOENT; goto free; } @@ -1626,7 +1626,7 @@ compat_get_entries(struct net *net, struct compat_ipt_get_entries __user *uptr, xt_compat_lock(AF_INET); t = xt_find_table_lock(net, AF_INET, get.name); - if (!IS_ERR_OR_NULL(t)) { + if (t) { const struct xt_table_info *private = t->private; struct xt_table_info info; ret = compat_table_info(private, &info); @@ -1640,7 +1640,7 @@ compat_get_entries(struct net *net, struct compat_ipt_get_entries __user *uptr, module_put(t->me); xt_table_unlock(t); } else - ret = t ? PTR_ERR(t) : -ENOENT; + ret = -ENOENT; xt_compat_unlock(AF_INET); return ret; diff --git a/net/ipv6/netfilter/ip6_tables.c b/net/ipv6/netfilter/ip6_tables.c index 7eac01d..6ff42b8 100644 --- a/net/ipv6/netfilter/ip6_tables.c +++ b/net/ipv6/netfilter/ip6_tables.c @@ -1003,7 +1003,7 @@ static int get_info(struct net *net, void __user *user, #endif t = try_then_request_module(xt_find_table_lock(net, AF_INET6, name), "ip6table_%s", name); - if (!IS_ERR_OR_NULL(t)) { + if (t) { struct ip6t_getinfo info; const struct xt_table_info *private = t->private; #ifdef CONFIG_COMPAT @@ -1033,7 +1033,7 @@ static int get_info(struct net *net, void __user *user, xt_table_unlock(t); module_put(t->me); } else - ret = t ? PTR_ERR(t) : -ENOENT; + ret = -ENOENT; #ifdef CONFIG_COMPAT if (compat) xt_compat_unlock(AF_INET6); @@ -1059,7 +1059,7 @@ get_entries(struct net *net, struct ip6t_get_entries __user *uptr, get.name[sizeof(get.name) - 1] = '\0'; t = xt_find_table_lock(net, AF_INET6, get.name); - if (!IS_ERR_OR_NULL(t)) { + if (t) { struct xt_table_info *private = t->private; if (get.size == private->size) ret = copy_entries_to_user(private->size, @@ -1070,7 +1070,7 @@ get_entries(struct net *net, struct ip6t_get_entries __user *uptr, module_put(t->me); xt_table_unlock(t); } else - ret = t ? PTR_ERR(t) : -ENOENT; + ret = -ENOENT; return ret; } @@ -1095,8 +1095,8 @@ __do_replace(struct net *net, const char *name, unsigned int valid_hooks, t = try_then_request_module(xt_find_table_lock(net, AF_INET6, name), "ip6table_%s", name); - if (IS_ERR_OR_NULL(t)) { - ret = t ? PTR_ERR(t) : -ENOENT; + if (!t) { + ret = -ENOENT; goto free_newinfo_counters_untrans; } @@ -1210,8 +1210,8 @@ do_add_counters(struct net *net, const void __user *user, unsigned int len, if (IS_ERR(paddc)) return PTR_ERR(paddc); t = xt_find_table_lock(net, AF_INET6, tmp.name); - if (IS_ERR_OR_NULL(t)) { - ret = t ? PTR_ERR(t) : -ENOENT; + if (!t) { + ret = -ENOENT; goto free; } @@ -1647,7 +1647,7 @@ compat_get_entries(struct net *net, struct compat_ip6t_get_entries __user *uptr, xt_compat_lock(AF_INET6); t = xt_find_table_lock(net, AF_INET6, get.name); - if (!IS_ERR_OR_NULL(t)) { + if (t) { const struct xt_table_info *private = t->private; struct xt_table_info info; ret = compat_table_info(private, &info); @@ -1661,7 +1661,7 @@ compat_get_entries(struct net *net, struct compat_ip6t_get_entries __user *uptr, module_put(t->me); xt_table_unlock(t); } else - ret = t ? PTR_ERR(t) : -ENOENT; + ret = -ENOENT; xt_compat_unlock(AF_INET6); return ret; diff --git a/net/netfilter/x_tables.c b/net/netfilter/x_tables.c index fc49774..ad818e5 100644 --- a/net/netfilter/x_tables.c +++ b/net/netfilter/x_tables.c @@ -982,7 +982,7 @@ void xt_free_table_info(struct xt_table_info *info) } EXPORT_SYMBOL(xt_free_table_info); -/* Find table by name, grabs mutex & ref. Returns ERR_PTR() on error. */ +/* Find table by name, grabs mutex & ref. Returns NULL on error. */ struct xt_table *xt_find_table_lock(struct net *net, u_int8_t af, const char *name) { -- 2.7.4