#ifdef CONFIG_PROC_SYSCTL
-#define SYSCTL_WRITES_LEGACY -1
-#define SYSCTL_WRITES_WARN 0
-#define SYSCTL_WRITES_STRICT 1
+/**
+ * enum sysctl_writes_mode - supported sysctl write modes
+ *
+ * @SYSCTL_WRITES_LEGACY: each write syscall must fully contain the sysctl value
+ * to be written, and multiple writes on the same sysctl file descriptor
+ * will rewrite the sysctl value, regardless of file position. No warning
+ * is issued when the initial position is not 0.
+ * @SYSCTL_WRITES_WARN: same as above but warn when the initial file position is
+ * not 0.
+ * @SYSCTL_WRITES_STRICT: writes to numeric sysctl entries must always be at
+ * file position 0 and the value must be fully contained in the buffer
+ * sent to the write syscall. If dealing with strings respect the file
+ * position, but restrict this to the max length of the buffer, anything
+ * passed the max lenght will be ignored. Multiple writes will append
+ * to the buffer.
+ *
+ * These write modes control how current file position affects the behavior of
+ * updating sysctl values through the proc interface on each write.
+ */
+enum sysctl_writes_mode {
+ SYSCTL_WRITES_LEGACY = -1,
+ SYSCTL_WRITES_WARN = 0,
+ SYSCTL_WRITES_STRICT = 1,
+};
-static int sysctl_writes_strict = SYSCTL_WRITES_STRICT;
+static enum sysctl_writes_mode sysctl_writes_strict = SYSCTL_WRITES_STRICT;
static int proc_do_cad_pid(struct ctl_table *table, int write,
void __user *buffer, size_t *lenp, loff_t *ppos);
.extra2 = &zero,
#endif
},
+ {
+ .procname = "watchdog_cpumask",
+ .data = &watchdog_cpumask_bits,
+ .maxlen = NR_CPUS,
+ .mode = 0644,
+ .proc_handler = proc_watchdog_cpumask,
+ },
+#ifdef CONFIG_SOFTLOCKUP_DETECTOR
{
.procname = "soft_watchdog",
.data = &soft_watchdog_enabled,
.extra1 = &zero,
.extra2 = &one,
},
- {
- .procname = "watchdog_cpumask",
- .data = &watchdog_cpumask_bits,
- .maxlen = NR_CPUS,
- .mode = 0644,
- .proc_handler = proc_watchdog_cpumask,
- },
{
.procname = "softlockup_panic",
.data = &softlockup_panic,
.extra1 = &zero,
.extra2 = &one,
},
-#ifdef CONFIG_HARDLOCKUP_DETECTOR
+#ifdef CONFIG_SMP
{
- .procname = "hardlockup_panic",
- .data = &hardlockup_panic,
+ .procname = "softlockup_all_cpu_backtrace",
+ .data = &sysctl_softlockup_all_cpu_backtrace,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = proc_dointvec_minmax,
.extra1 = &zero,
.extra2 = &one,
},
+#endif /* CONFIG_SMP */
#endif
-#ifdef CONFIG_SMP
+#ifdef CONFIG_HARDLOCKUP_DETECTOR
{
- .procname = "softlockup_all_cpu_backtrace",
- .data = &sysctl_softlockup_all_cpu_backtrace,
+ .procname = "hardlockup_panic",
+ .data = &hardlockup_panic,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = proc_dointvec_minmax,
.extra1 = &zero,
.extra2 = &one,
},
+#ifdef CONFIG_SMP
{
.procname = "hardlockup_all_cpu_backtrace",
.data = &sysctl_hardlockup_all_cpu_backtrace,
},
#endif /* CONFIG_SMP */
#endif
+#endif
+
#if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_X86)
{
.procname = "unknown_nmi_panic",
current->comm, table->procname);
}
+/**
+ * proc_first_pos_non_zero_ignore - check if firs position is allowed
+ * @ppos: file position
+ * @table: the sysctl table
+ *
+ * Returns true if the first position is non-zero and the sysctl_writes_strict
+ * mode indicates this is not allowed for numeric input types. String proc
+ * hadlers can ignore the return value.
+ */
+static bool proc_first_pos_non_zero_ignore(loff_t *ppos,
+ struct ctl_table *table)
+{
+ if (!*ppos)
+ return false;
+
+ switch (sysctl_writes_strict) {
+ case SYSCTL_WRITES_STRICT:
+ return true;
+ case SYSCTL_WRITES_WARN:
+ warn_sysctl_write(table);
+ return false;
+ default:
+ return false;
+ }
+}
+
/**
* proc_dostring - read a string sysctl
* @table: the sysctl table
int proc_dostring(struct ctl_table *table, int write,
void __user *buffer, size_t *lenp, loff_t *ppos)
{
- if (write && *ppos && sysctl_writes_strict == SYSCTL_WRITES_WARN)
- warn_sysctl_write(table);
+ if (write)
+ proc_first_pos_non_zero_ignore(ppos, table);
return _proc_do_string((char *)(table->data), table->maxlen, write,
(char __user *)buffer, lenp, ppos);
return 0;
}
-static int do_proc_douintvec_conv(bool *negp, unsigned long *lvalp,
- int *valp,
- int write, void *data)
+static int do_proc_douintvec_conv(unsigned long *lvalp,
+ unsigned int *valp,
+ int write, void *data)
{
if (write) {
- if (*negp)
+ if (*lvalp > UINT_MAX)
return -EINVAL;
if (*lvalp > UINT_MAX)
return -EINVAL;
*valp = *lvalp;
} else {
unsigned int val = *valp;
- *negp = false;
*lvalp = (unsigned long)val;
}
return 0;
conv = do_proc_dointvec_conv;
if (write) {
- if (*ppos) {
- switch (sysctl_writes_strict) {
- case SYSCTL_WRITES_STRICT:
- goto out;
- case SYSCTL_WRITES_WARN:
- warn_sysctl_write(table);
- break;
- default:
- break;
- }
- }
+ if (proc_first_pos_non_zero_ignore(ppos, table))
+ goto out;
if (left > PAGE_SIZE - 1)
left = PAGE_SIZE - 1;
buffer, lenp, ppos, conv, data);
}
+static int do_proc_douintvec_w(unsigned int *tbl_data,
+ struct ctl_table *table,
+ void __user *buffer,
+ size_t *lenp, loff_t *ppos,
+ int (*conv)(unsigned long *lvalp,
+ unsigned int *valp,
+ int write, void *data),
+ void *data)
+{
+ unsigned long lval;
+ int err = 0;
+ size_t left;
+ bool neg;
+ char *kbuf = NULL, *p;
+
+ left = *lenp;
+
+ if (proc_first_pos_non_zero_ignore(ppos, table))
+ goto bail_early;
+
+ if (left > PAGE_SIZE - 1)
+ left = PAGE_SIZE - 1;
+
+ p = kbuf = memdup_user_nul(buffer, left);
+ if (IS_ERR(kbuf))
+ return -EINVAL;
+
+ left -= proc_skip_spaces(&p);
+ if (!left) {
+ err = -EINVAL;
+ goto out_free;
+ }
+
+ err = proc_get_long(&p, &left, &lval, &neg,
+ proc_wspace_sep,
+ sizeof(proc_wspace_sep), NULL);
+ if (err || neg) {
+ err = -EINVAL;
+ goto out_free;
+ }
+
+ if (conv(&lval, tbl_data, 1, data)) {
+ err = -EINVAL;
+ goto out_free;
+ }
+
+ if (!err && left)
+ left -= proc_skip_spaces(&p);
+
+out_free:
+ kfree(kbuf);
+ if (err)
+ return -EINVAL;
+
+ return 0;
+
+ /* This is in keeping with old __do_proc_dointvec() */
+bail_early:
+ *ppos += *lenp;
+ return err;
+}
+
+static int do_proc_douintvec_r(unsigned int *tbl_data, void __user *buffer,
+ size_t *lenp, loff_t *ppos,
+ int (*conv)(unsigned long *lvalp,
+ unsigned int *valp,
+ int write, void *data),
+ void *data)
+{
+ unsigned long lval;
+ int err = 0;
+ size_t left;
+
+ left = *lenp;
+
+ if (conv(&lval, tbl_data, 0, data)) {
+ err = -EINVAL;
+ goto out;
+ }
+
+ err = proc_put_long(&buffer, &left, lval, false);
+ if (err || !left)
+ goto out;
+
+ err = proc_put_char(&buffer, &left, '\n');
+
+out:
+ *lenp -= left;
+ *ppos += *lenp;
+
+ return err;
+}
+
+static int __do_proc_douintvec(void *tbl_data, struct ctl_table *table,
+ int write, void __user *buffer,
+ size_t *lenp, loff_t *ppos,
+ int (*conv)(unsigned long *lvalp,
+ unsigned int *valp,
+ int write, void *data),
+ void *data)
+{
+ unsigned int *i, vleft;
+
+ if (!tbl_data || !table->maxlen || !*lenp || (*ppos && !write)) {
+ *lenp = 0;
+ return 0;
+ }
+
+ i = (unsigned int *) tbl_data;
+ vleft = table->maxlen / sizeof(*i);
+
+ /*
+ * Arrays are not supported, keep this simple. *Do not* add
+ * support for them.
+ */
+ if (vleft != 1) {
+ *lenp = 0;
+ return -EINVAL;
+ }
+
+ if (!conv)
+ conv = do_proc_douintvec_conv;
+
+ if (write)
+ return do_proc_douintvec_w(i, table, buffer, lenp, ppos,
+ conv, data);
+ return do_proc_douintvec_r(i, buffer, lenp, ppos, conv, data);
+}
+
+static int do_proc_douintvec(struct ctl_table *table, int write,
+ void __user *buffer, size_t *lenp, loff_t *ppos,
+ int (*conv)(unsigned long *lvalp,
+ unsigned int *valp,
+ int write, void *data),
+ void *data)
+{
+ return __do_proc_douintvec(table->data, table, write,
+ buffer, lenp, ppos, conv, data);
+}
+
/**
* proc_dointvec - read a vector of integers
* @table: the sysctl table
int proc_douintvec(struct ctl_table *table, int write,
void __user *buffer, size_t *lenp, loff_t *ppos)
{
- return do_proc_dointvec(table, write, buffer, lenp, ppos,
- do_proc_douintvec_conv, NULL);
+ return do_proc_douintvec(table, write, buffer, lenp, ppos,
+ do_proc_douintvec_conv, NULL);
}
/*
do_proc_dointvec_minmax_conv, ¶m);
}
+struct do_proc_douintvec_minmax_conv_param {
+ unsigned int *min;
+ unsigned int *max;
+};
+
+static int do_proc_douintvec_minmax_conv(unsigned long *lvalp,
+ unsigned int *valp,
+ int write, void *data)
+{
+ struct do_proc_douintvec_minmax_conv_param *param = data;
+
+ if (write) {
+ unsigned int val = *lvalp;
+
+ if ((param->min && *param->min > val) ||
+ (param->max && *param->max < val))
+ return -ERANGE;
+
+ if (*lvalp > UINT_MAX)
+ return -EINVAL;
+ *valp = val;
+ } else {
+ unsigned int val = *valp;
+ *lvalp = (unsigned long) val;
+ }
+
+ return 0;
+}
+
+/**
+ * proc_douintvec_minmax - read a vector of unsigned ints with min/max values
+ * @table: the sysctl table
+ * @write: %TRUE if this is a write to the sysctl file
+ * @buffer: the user buffer
+ * @lenp: the size of the user buffer
+ * @ppos: file position
+ *
+ * Reads/writes up to table->maxlen/sizeof(unsigned int) unsigned integer
+ * values from/to the user buffer, treated as an ASCII string. Negative
+ * strings are not allowed.
+ *
+ * This routine will ensure the values are within the range specified by
+ * table->extra1 (min) and table->extra2 (max). There is a final sanity
+ * check for UINT_MAX to avoid having to support wrap around uses from
+ * userspace.
+ *
+ * Returns 0 on success.
+ */
+int proc_douintvec_minmax(struct ctl_table *table, int write,
+ void __user *buffer, size_t *lenp, loff_t *ppos)
+{
+ struct do_proc_douintvec_minmax_conv_param param = {
+ .min = (unsigned int *) table->extra1,
+ .max = (unsigned int *) table->extra2,
+ };
+ return do_proc_douintvec(table, write, buffer, lenp, ppos,
+ do_proc_douintvec_minmax_conv, ¶m);
+}
+
static void validate_coredump_safety(void)
{
#ifdef CONFIG_COREDUMP
left = *lenp;
if (write) {
- if (*ppos) {
- switch (sysctl_writes_strict) {
- case SYSCTL_WRITES_STRICT:
- goto out;
- case SYSCTL_WRITES_WARN:
- warn_sysctl_write(table);
- break;
- default:
- break;
- }
- }
+ if (proc_first_pos_non_zero_ignore(ppos, table))
+ goto out;
if (left > PAGE_SIZE - 1)
left = PAGE_SIZE - 1;
return -ENOSYS;
}
+int proc_douintvec_minmax(struct ctl_table *table, int write,
+ void __user *buffer, size_t *lenp, loff_t *ppos)
+{
+ return -ENOSYS;
+}
+
int proc_dointvec_jiffies(struct ctl_table *table, int write,
void __user *buffer, size_t *lenp, loff_t *ppos)
{
EXPORT_SYMBOL(proc_douintvec);
EXPORT_SYMBOL(proc_dointvec_jiffies);
EXPORT_SYMBOL(proc_dointvec_minmax);
+EXPORT_SYMBOL_GPL(proc_douintvec_minmax);
EXPORT_SYMBOL(proc_dointvec_userhz_jiffies);
EXPORT_SYMBOL(proc_dointvec_ms_jiffies);
EXPORT_SYMBOL(proc_dostring);
projects / karo-tx-linux.git / blobdiff