diff options
| -rw-r--r-- | fs/proc/proc_sysctl.c | 14 | ||||
| -rw-r--r-- | kernel/sysctl-test.c | 49 | ||||
| -rw-r--r-- | kernel/sysctl.c | 10 |
3 files changed, 65 insertions, 8 deletions
diff --git a/fs/proc/proc_sysctl.c b/fs/proc/proc_sysctl.c index dd7b462387a0..c467e36741d0 100644 --- a/fs/proc/proc_sysctl.c +++ b/fs/proc/proc_sysctl.c @@ -1091,6 +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) || @@ -1102,6 +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) { diff --git a/kernel/sysctl-test.c b/kernel/sysctl-test.c index 6ef887c19c48..4e7dcc9187e2 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), {} }; diff --git a/kernel/sysctl.c b/kernel/sysctl.c index e0b917328cf9..c0a1164eaf59 100644 --- a/kernel/sysctl.c +++ b/kernel/sysctl.c @@ -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; |