diff --git a/fs/proc/proc_sysctl.c b/fs/proc/proc_sysctl.c index b1c2c0b82116..9553e77c9d31 100644 --- a/fs/proc/proc_sysctl.c +++ b/fs/proc/proc_sysctl.c @@ -21,7 +21,7 @@ #define list_for_each_table_entry(entry, header) \ entry = header->ctl_table; \ - for (size_t i = 0 ; i < header->ctl_table_size && entry->procname; ++i, entry++) + for (size_t i = 0 ; i < header->ctl_table_size; ++i, entry++) static const struct dentry_operations proc_sys_dentry_operations; static const struct file_operations proc_sys_file_operations; @@ -476,12 +476,10 @@ static struct inode *proc_sys_make_inode(struct super_block *sb, make_empty_dir_inode(inode); } + inode->i_uid = GLOBAL_ROOT_UID; + inode->i_gid = GLOBAL_ROOT_GID; if (root->set_ownership) root->set_ownership(head, &inode->i_uid, &inode->i_gid); - else { - inode->i_uid = GLOBAL_ROOT_UID; - inode->i_gid = GLOBAL_ROOT_GID; - } return inode; } @@ -951,14 +949,14 @@ static struct ctl_dir *new_dir(struct ctl_table_set *set, char *new_name; new = kzalloc(sizeof(*new) + sizeof(struct ctl_node) + - sizeof(struct ctl_table)*2 + namelen + 1, + sizeof(struct ctl_table) + namelen + 1, GFP_KERNEL); if (!new) return NULL; node = (struct ctl_node *)(new + 1); table = (struct ctl_table *)(node + 1); - new_name = (char *)(table + 2); + new_name = (char *)(table + 1); memcpy(new_name, name, namelen); table[0].procname = new_name; table[0].mode = S_IFDIR|S_IRUGO|S_IXUGO; @@ -1093,6 +1091,7 @@ static int sysctl_err(const char *path, struct ctl_table *table, char *fmt, ...) static int sysctl_check_table_array(const char *path, struct ctl_table *table) { + unsigned int extra; int err = 0; if ((table->proc_handler == proc_douintvec) || @@ -1104,6 +1103,19 @@ static int sysctl_check_table_array(const char *path, struct ctl_table *table) if (table->proc_handler == proc_dou8vec_minmax) { if (table->maxlen != sizeof(u8)) err |= sysctl_err(path, table, "array not allowed"); + + if (table->extra1) { + extra = *(unsigned int *) table->extra1; + if (extra > 255U) + err |= sysctl_err(path, table, + "range value too large for proc_dou8vec_minmax"); + } + if (table->extra2) { + extra = *(unsigned int *) table->extra2; + if (extra > 255U) + err |= sysctl_err(path, table, + "range value too large for proc_dou8vec_minmax"); + } } if (table->proc_handler == proc_dobool) { @@ -1119,6 +1131,8 @@ static int sysctl_check_table(const char *path, struct ctl_table_header *header) struct ctl_table *entry; int err = 0; list_for_each_table_entry(entry, header) { + if (!entry->procname) + err |= sysctl_err(path, entry, "procname is null"); if ((entry->proc_handler == proc_dostring) || (entry->proc_handler == proc_dobool) || (entry->proc_handler == proc_dointvec) || @@ -1154,18 +1168,16 @@ static struct ctl_table_header *new_links(struct ctl_dir *dir, struct ctl_table_ struct ctl_table_header *links; struct ctl_node *node; char *link_name; - int nr_entries, name_bytes; + int name_bytes; name_bytes = 0; - nr_entries = 0; list_for_each_table_entry(entry, head) { - nr_entries++; name_bytes += strlen(entry->procname) + 1; } links = kzalloc(sizeof(struct ctl_table_header) + - sizeof(struct ctl_node)*nr_entries + - sizeof(struct ctl_table)*(nr_entries + 1) + + sizeof(struct ctl_node)*head->ctl_table_size + + sizeof(struct ctl_table)*head->ctl_table_size + name_bytes, GFP_KERNEL); @@ -1173,8 +1185,8 @@ static struct ctl_table_header *new_links(struct ctl_dir *dir, struct ctl_table_ return NULL; node = (struct ctl_node *)(links + 1); - link_table = (struct ctl_table *)(node + nr_entries); - link_name = (char *)&link_table[nr_entries + 1]; + link_table = (struct ctl_table *)(node + head->ctl_table_size); + link_name = (char *)(link_table + head->ctl_table_size); link = link_table; list_for_each_table_entry(entry, head) { @@ -1188,7 +1200,7 @@ static struct ctl_table_header *new_links(struct ctl_dir *dir, struct ctl_table_ } init_header(links, dir->header.root, dir->header.set, node, link_table, head->ctl_table_size); - links->nreg = nr_entries; + links->nreg = head->ctl_table_size; return links; } @@ -1300,28 +1312,23 @@ static struct ctl_dir *sysctl_mkdir_p(struct ctl_dir *dir, const char *path) * __register_sysctl_table - register a leaf sysctl table * @set: Sysctl tree to register on * @path: The path to the directory the sysctl table is in. - * @table: the top-level table structure without any child. This table - * should not be free'd after registration. So it should not be - * used on stack. It can either be a global or dynamically allocated - * by the caller and free'd later after sysctl unregistration. + * + * @table: the top-level table structure. This table should not be free'd + * after registration. So it should not be used on stack. It can either + * be a global or dynamically allocated by the caller and free'd later + * after sysctl unregistration. * @table_size : The number of elements in table * * Register a sysctl table hierarchy. @table should be a filled in ctl_table - * array. A completely 0 filled entry terminates the table. + * array. * * The members of the &struct ctl_table structure are used as follows: - * * procname - the name of the sysctl file under /proc/sys. Set to %NULL to not * enter a sysctl file - * - * data - a pointer to data for use by proc_handler - * - * maxlen - the maximum size in bytes of the data - * - * mode - the file permissions for the /proc/sys file - * - * child - must be %NULL. - * + * data - a pointer to data for use by proc_handler + * maxlen - the maximum size in bytes of the data + * mode - the file permissions for the /proc/sys file + * type - Defines the target type (described in struct definition) * proc_handler - the text handler routine (described below) * * extra1, extra2 - extra pointers usable by the proc handler routines @@ -1329,8 +1336,7 @@ static struct ctl_dir *sysctl_mkdir_p(struct ctl_dir *dir, const char *path) * [0] https://lkml.kernel.org/87zgpte9o4.fsf@email.froward.int.ebiederm.org * * Leaf nodes in the sysctl tree will be represented by a single file - * under /proc; non-leaf nodes (where child is not NULL) are not allowed, - * sysctl_check_table() verifies this. + * under /proc; non-leaf nodes are not allowed. * * There must be a proc_handler routine for any terminal nodes. * Several default handlers are available to cover common cases - diff --git a/include/linux/sysctl.h b/include/linux/sysctl.h index 09db2f2e6488..54fbec062772 100644 --- a/include/linux/sysctl.h +++ b/include/linux/sysctl.h @@ -237,7 +237,7 @@ extern struct ctl_table_header *register_sysctl_mount_point(const char *path); void do_sysctl_args(void); bool sysctl_is_alias(char *param); -int do_proc_douintvec(struct ctl_table *table, int write, +int do_proc_douintvec(const struct ctl_table *table, int write, void *buffer, size_t *lenp, loff_t *ppos, int (*conv)(unsigned long *lvalp, unsigned int *valp, diff --git a/kernel/locking/lockdep.c b/kernel/locking/lockdep.c index 151bd3de5936..726b22ce7d0b 100644 --- a/kernel/locking/lockdep.c +++ b/kernel/locking/lockdep.c @@ -97,7 +97,6 @@ static struct ctl_table kern_lockdep_table[] = { .proc_handler = proc_dointvec, }, #endif /* CONFIG_LOCK_STAT */ - { } }; static __init int kernel_lockdep_sysctls_init(void) diff --git a/kernel/sysctl-test.c b/kernel/sysctl-test.c index 6ef887c19c48..3ac98bb7fb82 100644 --- a/kernel/sysctl-test.c +++ b/kernel/sysctl-test.c @@ -367,6 +367,54 @@ static void sysctl_test_api_dointvec_write_single_greater_int_max( KUNIT_EXPECT_EQ(test, 0, *((int *)table.data)); } +/* + * Test that registering an invalid extra value is not allowed. + */ +static void sysctl_test_register_sysctl_sz_invalid_extra_value( + struct kunit *test) +{ + unsigned char data = 0; + struct ctl_table table_foo[] = { + { + .procname = "foo", + .data = &data, + .maxlen = sizeof(u8), + .mode = 0644, + .proc_handler = proc_dou8vec_minmax, + .extra1 = SYSCTL_FOUR, + .extra2 = SYSCTL_ONE_THOUSAND, + }, + }; + + struct ctl_table table_bar[] = { + { + .procname = "bar", + .data = &data, + .maxlen = sizeof(u8), + .mode = 0644, + .proc_handler = proc_dou8vec_minmax, + .extra1 = SYSCTL_NEG_ONE, + .extra2 = SYSCTL_ONE_HUNDRED, + }, + }; + + struct ctl_table table_qux[] = { + { + .procname = "qux", + .data = &data, + .maxlen = sizeof(u8), + .mode = 0644, + .proc_handler = proc_dou8vec_minmax, + .extra1 = SYSCTL_ZERO, + .extra2 = SYSCTL_TWO_HUNDRED, + }, + }; + + KUNIT_EXPECT_NULL(test, register_sysctl("foo", table_foo)); + KUNIT_EXPECT_NULL(test, register_sysctl("foo", table_bar)); + KUNIT_EXPECT_NOT_NULL(test, register_sysctl("foo", table_qux)); +} + static struct kunit_case sysctl_test_cases[] = { KUNIT_CASE(sysctl_test_api_dointvec_null_tbl_data), KUNIT_CASE(sysctl_test_api_dointvec_table_maxlen_unset), @@ -378,6 +426,7 @@ static struct kunit_case sysctl_test_cases[] = { KUNIT_CASE(sysctl_test_dointvec_write_happy_single_negative), KUNIT_CASE(sysctl_test_api_dointvec_write_single_less_int_min), KUNIT_CASE(sysctl_test_api_dointvec_write_single_greater_int_max), + KUNIT_CASE(sysctl_test_register_sysctl_sz_invalid_extra_value), {} }; @@ -388,4 +437,5 @@ static struct kunit_suite sysctl_test_suite = { kunit_test_suites(&sysctl_test_suite); +MODULE_DESCRIPTION("KUnit test of proc sysctl"); MODULE_LICENSE("GPL v2"); diff --git a/kernel/sysctl.c b/kernel/sysctl.c index e0b917328cf9..e4421594fc25 100644 --- a/kernel/sysctl.c +++ b/kernel/sysctl.c @@ -205,7 +205,7 @@ static int _proc_do_string(char *data, int maxlen, int write, return 0; } -static void warn_sysctl_write(struct ctl_table *table) +static void warn_sysctl_write(const struct ctl_table *table) { pr_warn_once("%s wrote to %s when file position was not 0!\n" "This will not be supported in the future. To silence this\n" @@ -223,7 +223,7 @@ static void warn_sysctl_write(struct ctl_table *table) * handlers can ignore the return value. */ static bool proc_first_pos_non_zero_ignore(loff_t *ppos, - struct ctl_table *table) + const struct ctl_table *table) { if (!*ppos) return false; @@ -468,7 +468,7 @@ static int do_proc_douintvec_conv(unsigned long *lvalp, static const char proc_wspace_sep[] = { ' ', '\t', '\n' }; -static int __do_proc_dointvec(void *tbl_data, struct ctl_table *table, +static int __do_proc_dointvec(void *tbl_data, const struct ctl_table *table, int write, void *buffer, size_t *lenp, loff_t *ppos, int (*conv)(bool *negp, unsigned long *lvalp, int *valp, @@ -541,7 +541,7 @@ out: return err; } -static int do_proc_dointvec(struct ctl_table *table, int write, +static int do_proc_dointvec(const struct ctl_table *table, int write, void *buffer, size_t *lenp, loff_t *ppos, int (*conv)(bool *negp, unsigned long *lvalp, int *valp, int write, void *data), @@ -552,7 +552,7 @@ static int do_proc_dointvec(struct ctl_table *table, int write, } static int do_proc_douintvec_w(unsigned int *tbl_data, - struct ctl_table *table, + const struct ctl_table *table, void *buffer, size_t *lenp, loff_t *ppos, int (*conv)(unsigned long *lvalp, @@ -639,7 +639,7 @@ out: return err; } -static int __do_proc_douintvec(void *tbl_data, struct ctl_table *table, +static int __do_proc_douintvec(void *tbl_data, const struct ctl_table *table, int write, void *buffer, size_t *lenp, loff_t *ppos, int (*conv)(unsigned long *lvalp, @@ -675,7 +675,7 @@ static int __do_proc_douintvec(void *tbl_data, struct ctl_table *table, return do_proc_douintvec_r(i, buffer, lenp, ppos, conv, data); } -int do_proc_douintvec(struct ctl_table *table, int write, +int do_proc_douintvec(const struct ctl_table *table, int write, void *buffer, size_t *lenp, loff_t *ppos, int (*conv)(unsigned long *lvalp, unsigned int *valp, @@ -977,16 +977,10 @@ int proc_dou8vec_minmax(struct ctl_table *table, int write, if (table->maxlen != sizeof(u8)) return -EINVAL; - if (table->extra1) { + if (table->extra1) min = *(unsigned int *) table->extra1; - if (min > 255U) - return -EINVAL; - } - if (table->extra2) { + if (table->extra2) max = *(unsigned int *) table->extra2; - if (max > 255U) - return -EINVAL; - } tmp = *table; @@ -1023,8 +1017,9 @@ static int sysrq_sysctl_handler(struct ctl_table *table, int write, } #endif -static int __do_proc_doulongvec_minmax(void *data, struct ctl_table *table, - int write, void *buffer, size_t *lenp, loff_t *ppos, +static int __do_proc_doulongvec_minmax(void *data, + const struct ctl_table *table, int write, + void *buffer, size_t *lenp, loff_t *ppos, unsigned long convmul, unsigned long convdiv) { unsigned long *i, *min, *max; @@ -1096,7 +1091,7 @@ out: return err; } -static int do_proc_doulongvec_minmax(struct ctl_table *table, int write, +static int do_proc_doulongvec_minmax(const struct ctl_table *table, int write, void *buffer, size_t *lenp, loff_t *ppos, unsigned long convmul, unsigned long convdiv) { diff --git a/kernel/utsname_sysctl.c b/kernel/utsname_sysctl.c index 76a772072557..04e4513f2985 100644 --- a/kernel/utsname_sysctl.c +++ b/kernel/utsname_sysctl.c @@ -15,7 +15,7 @@ #ifdef CONFIG_PROC_SYSCTL -static void *get_uts(struct ctl_table *table) +static void *get_uts(const struct ctl_table *table) { char *which = table->data; struct uts_namespace *uts_ns; diff --git a/lib/alloc_tag.c b/lib/alloc_tag.c index c347b8b72d78..81e5f9a70f22 100644 --- a/lib/alloc_tag.c +++ b/lib/alloc_tag.c @@ -239,7 +239,6 @@ static struct ctl_table memory_allocation_profiling_sysctls[] = { #endif .proc_handler = proc_do_static_key, }, - { } }; static void __init sysctl_init(void) diff --git a/net/sysctl_net.c b/net/sysctl_net.c index f5017012a049..19e8048241ba 100644 --- a/net/sysctl_net.c +++ b/net/sysctl_net.c @@ -127,7 +127,7 @@ static void ensure_safe_net_sysctl(struct net *net, const char *path, pr_debug("Registering net sysctl (net %p): %s\n", net, path); ent = table; - for (size_t i = 0; i < table_size && ent->procname; ent++, i++) { + for (size_t i = 0; i < table_size; ent++, i++) { unsigned long addr; const char *where; @@ -165,17 +165,10 @@ struct ctl_table_header *register_net_sysctl_sz(struct net *net, struct ctl_table *table, size_t table_size) { - int count; - struct ctl_table *entry; - if (!net_eq(net, &init_net)) ensure_safe_net_sysctl(net, path, table, table_size); - entry = table; - for (count = 0 ; count < table_size && entry->procname; entry++, count++) - ; - - return __register_sysctl_table(&net->sysctls, path, table, count); + return __register_sysctl_table(&net->sysctls, path, table, table_size); } EXPORT_SYMBOL_GPL(register_net_sysctl_sz);