diff options
| -rw-r--r-- | fs/proc/proc_sysctl.c | 4 | ||||
| -rw-r--r-- | include/linux/sysctl.h | 7 | ||||
| -rw-r--r-- | kernel/sysctl.c | 25 |
3 files changed, 26 insertions, 10 deletions
diff --git a/fs/proc/proc_sysctl.c b/fs/proc/proc_sysctl.c index 5e31585292a..5acc001d49f 100644 --- a/fs/proc/proc_sysctl.c +++ b/fs/proc/proc_sysctl.c @@ -190,7 +190,7 @@ static ssize_t proc_sys_call_handler(struct file *filp, void __user *buf, * and won't be until we finish. */ error = -EPERM; - if (sysctl_perm(table, write ? MAY_WRITE : MAY_READ)) + if (sysctl_perm(head->root, table, write ? MAY_WRITE : MAY_READ)) goto out; /* careful: calling conventions are nasty here */ @@ -388,7 +388,7 @@ static int proc_sys_permission(struct inode *inode, int mask, struct nameidata * goto out; /* Use the permissions on the sysctl table entry */ - error = sysctl_perm(table, mask); + error = sysctl_perm(head->root, table, mask); out: sysctl_head_finish(head); return error; diff --git a/include/linux/sysctl.h b/include/linux/sysctl.h index 39eafd8f97a..24141b4d1a1 100644 --- a/include/linux/sysctl.h +++ b/include/linux/sysctl.h @@ -945,11 +945,14 @@ enum /* For the /proc/sys support */ struct ctl_table; struct nsproxy; +struct ctl_table_root; + extern struct ctl_table_header *sysctl_head_next(struct ctl_table_header *prev); extern struct ctl_table_header *__sysctl_head_next(struct nsproxy *namespaces, struct ctl_table_header *prev); extern void sysctl_head_finish(struct ctl_table_header *prev); -extern int sysctl_perm(struct ctl_table *table, int op); +extern int sysctl_perm(struct ctl_table_root *root, + struct ctl_table *table, int op); typedef struct ctl_table ctl_table; @@ -1049,6 +1052,8 @@ struct ctl_table_root { struct list_head header_list; struct list_head *(*lookup)(struct ctl_table_root *root, struct nsproxy *namespaces); + int (*permissions)(struct ctl_table_root *root, + struct nsproxy *namespaces, struct ctl_table *table); }; /* struct ctl_table_header is used to maintain dynamic lists of diff --git a/kernel/sysctl.c b/kernel/sysctl.c index 874e813e40c..d7ffdc59816 100644 --- a/kernel/sysctl.c +++ b/kernel/sysctl.c @@ -1434,7 +1434,8 @@ void register_sysctl_root(struct ctl_table_root *root) #ifdef CONFIG_SYSCTL_SYSCALL /* Perform the actual read/write of a sysctl table entry. */ -static int do_sysctl_strategy(struct ctl_table *table, +static int do_sysctl_strategy(struct ctl_table_root *root, + struct ctl_table *table, int __user *name, int nlen, void __user *oldval, size_t __user *oldlenp, void __user *newval, size_t newlen) @@ -1445,7 +1446,7 @@ static int do_sysctl_strategy(struct ctl_table *table, op |= 004; if (newval) op |= 002; - if (sysctl_perm(table, op)) + if (sysctl_perm(root, table, op)) return -EPERM; if (table->strategy) { @@ -1471,6 +1472,7 @@ static int do_sysctl_strategy(struct ctl_table *table, static int parse_table(int __user *name, int nlen, void __user *oldval, size_t __user *oldlenp, void __user *newval, size_t newlen, + struct ctl_table_root *root, struct ctl_table *table) { int n; @@ -1485,14 +1487,14 @@ repeat: if (n == table->ctl_name) { int error; if (table->child) { - if (sysctl_perm(table, 001)) + if (sysctl_perm(root, table, 001)) return -EPERM; name++; nlen--; table = table->child; goto repeat; } - error = do_sysctl_strategy(table, name, nlen, + error = do_sysctl_strategy(root, table, name, nlen, oldval, oldlenp, newval, newlen); return error; @@ -1518,7 +1520,8 @@ int do_sysctl(int __user *name, int nlen, void __user *oldval, size_t __user *ol for (head = sysctl_head_next(NULL); head; head = sysctl_head_next(head)) { error = parse_table(name, nlen, oldval, oldlenp, - newval, newlen, head->ctl_table); + newval, newlen, + head->root, head->ctl_table); if (error != -ENOTDIR) { sysctl_head_finish(head); break; @@ -1564,13 +1567,21 @@ static int test_perm(int mode, int op) return -EACCES; } -int sysctl_perm(struct ctl_table *table, int op) +int sysctl_perm(struct ctl_table_root *root, struct ctl_table *table, int op) { int error; + int mode; + error = security_sysctl(table, op); if (error) return error; - return test_perm(table->mode, op); + + if (root->permissions) + mode = root->permissions(root, current->nsproxy, table); + else + mode = table->mode; + + return test_perm(mode, op); } static void sysctl_set_parent(struct ctl_table *parent, struct ctl_table *table) |