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Diffstat (limited to 'kernel/sysctl.c')
-rw-r--r--kernel/sysctl.c588
1 files changed, 424 insertions, 164 deletions
diff --git a/kernel/sysctl.c b/kernel/sysctl.c
index 8686b0f5fc12..4c93486b45d1 100644
--- a/kernel/sysctl.c
+++ b/kernel/sysctl.c
@@ -52,6 +52,7 @@
#include <linux/slow-work.h>
#include <linux/perf_event.h>
#include <linux/kprobes.h>
+#include <linux/pipe_fs_i.h>
#include <asm/uaccess.h>
#include <asm/processor.h>
@@ -163,6 +164,27 @@ static int proc_taint(struct ctl_table *table, int write,
void __user *buffer, size_t *lenp, loff_t *ppos);
#endif
+#ifdef CONFIG_MAGIC_SYSRQ
+static int __sysrq_enabled; /* Note: sysrq code ises it's own private copy */
+
+static int sysrq_sysctl_handler(ctl_table *table, int write,
+ void __user *buffer, size_t *lenp,
+ loff_t *ppos)
+{
+ int error;
+
+ error = proc_dointvec(table, write, buffer, lenp, ppos);
+ if (error)
+ return error;
+
+ if (write)
+ sysrq_toggle_support(__sysrq_enabled);
+
+ return 0;
+}
+
+#endif
+
static struct ctl_table root_table[];
static struct ctl_table_root sysctl_table_root;
static struct ctl_table_header root_table_header = {
@@ -567,7 +589,7 @@ static struct ctl_table kern_table[] = {
.data = &__sysrq_enabled,
.maxlen = sizeof (int),
.mode = 0644,
- .proc_handler = proc_dointvec,
+ .proc_handler = sysrq_sysctl_handler,
},
#endif
#ifdef CONFIG_PROC_SYSCTL
@@ -621,7 +643,7 @@ static struct ctl_table kern_table[] = {
#endif
{
.procname = "userprocess_debug",
- .data = &sysctl_userprocess_debug,
+ .data = &show_unhandled_signals,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = proc_dointvec,
@@ -1423,6 +1445,14 @@ static struct ctl_table fs_table[] = {
.child = binfmt_misc_table,
},
#endif
+ {
+ .procname = "pipe-max-pages",
+ .data = &pipe_max_pages,
+ .maxlen = sizeof(int),
+ .mode = 0644,
+ .proc_handler = &proc_dointvec_minmax,
+ .extra1 = &two,
+ },
/*
* NOTE: do not add new entries to this table unless you have read
* Documentation/sysctl/ctl_unnumbered.txt
@@ -1431,7 +1461,8 @@ static struct ctl_table fs_table[] = {
};
static struct ctl_table debug_table[] = {
-#if defined(CONFIG_X86) || defined(CONFIG_PPC) || defined(CONFIG_SPARC)
+#if defined(CONFIG_X86) || defined(CONFIG_PPC) || defined(CONFIG_SPARC) || \
+ defined(CONFIG_S390)
{
.procname = "exception-trace",
.data = &show_unhandled_signals,
@@ -2040,8 +2071,132 @@ int proc_dostring(struct ctl_table *table, int write,
buffer, lenp, ppos);
}
+static size_t proc_skip_spaces(char **buf)
+{
+ size_t ret;
+ char *tmp = skip_spaces(*buf);
+ ret = tmp - *buf;
+ *buf = tmp;
+ return ret;
+}
+
+static void proc_skip_char(char **buf, size_t *size, const char v)
+{
+ while (*size) {
+ if (**buf != v)
+ break;
+ (*size)--;
+ (*buf)++;
+ }
+}
+
+#define TMPBUFLEN 22
+/**
+ * proc_get_long - reads an ASCII formatted integer from a user buffer
+ *
+ * @buf: a kernel buffer
+ * @size: size of the kernel buffer
+ * @val: this is where the number will be stored
+ * @neg: set to %TRUE if number is negative
+ * @perm_tr: a vector which contains the allowed trailers
+ * @perm_tr_len: size of the perm_tr vector
+ * @tr: pointer to store the trailer character
+ *
+ * In case of success %0 is returned and @buf and @size are updated with
+ * the amount of bytes read. If @tr is non-NULL and a trailing
+ * character exists (size is non-zero after returning from this
+ * function), @tr is updated with the trailing character.
+ */
+static int proc_get_long(char **buf, size_t *size,
+ unsigned long *val, bool *neg,
+ const char *perm_tr, unsigned perm_tr_len, char *tr)
+{
+ int len;
+ char *p, tmp[TMPBUFLEN];
+
+ if (!*size)
+ return -EINVAL;
+
+ len = *size;
+ if (len > TMPBUFLEN - 1)
+ len = TMPBUFLEN - 1;
+
+ memcpy(tmp, *buf, len);
+
+ tmp[len] = 0;
+ p = tmp;
+ if (*p == '-' && *size > 1) {
+ *neg = true;
+ p++;
+ } else
+ *neg = false;
+ if (!isdigit(*p))
+ return -EINVAL;
+
+ *val = simple_strtoul(p, &p, 0);
+
+ len = p - tmp;
+
+ /* We don't know if the next char is whitespace thus we may accept
+ * invalid integers (e.g. 1234...a) or two integers instead of one
+ * (e.g. 123...1). So lets not allow such large numbers. */
+ if (len == TMPBUFLEN - 1)
+ return -EINVAL;
+
+ if (len < *size && perm_tr_len && !memchr(perm_tr, *p, perm_tr_len))
+ return -EINVAL;
+
+ if (tr && (len < *size))
+ *tr = *p;
+
+ *buf += len;
+ *size -= len;
+
+ return 0;
+}
+
+/**
+ * proc_put_long - converts an integer to a decimal ASCII formatted string
+ *
+ * @buf: the user buffer
+ * @size: the size of the user buffer
+ * @val: the integer to be converted
+ * @neg: sign of the number, %TRUE for negative
+ *
+ * In case of success %0 is returned and @buf and @size are updated with
+ * the amount of bytes written.
+ */
+static int proc_put_long(void __user **buf, size_t *size, unsigned long val,
+ bool neg)
+{
+ int len;
+ char tmp[TMPBUFLEN], *p = tmp;
+
+ sprintf(p, "%s%lu", neg ? "-" : "", val);
+ len = strlen(tmp);
+ if (len > *size)
+ len = *size;
+ if (copy_to_user(*buf, tmp, len))
+ return -EFAULT;
+ *size -= len;
+ *buf += len;
+ return 0;
+}
+#undef TMPBUFLEN
+
+static int proc_put_char(void __user **buf, size_t *size, char c)
+{
+ if (*size) {
+ char __user **buffer = (char __user **)buf;
+ if (put_user(c, *buffer))
+ return -EFAULT;
+ (*size)--, (*buffer)++;
+ *buf = *buffer;
+ }
+ return 0;
+}
-static int do_proc_dointvec_conv(int *negp, unsigned long *lvalp,
+static int do_proc_dointvec_conv(bool *negp, unsigned long *lvalp,
int *valp,
int write, void *data)
{
@@ -2050,33 +2205,31 @@ static int do_proc_dointvec_conv(int *negp, unsigned long *lvalp,
} else {
int val = *valp;
if (val < 0) {
- *negp = -1;
+ *negp = true;
*lvalp = (unsigned long)-val;
} else {
- *negp = 0;
+ *negp = false;
*lvalp = (unsigned long)val;
}
}
return 0;
}
+static const char proc_wspace_sep[] = { ' ', '\t', '\n' };
+
static int __do_proc_dointvec(void *tbl_data, struct ctl_table *table,
int write, void __user *buffer,
size_t *lenp, loff_t *ppos,
- int (*conv)(int *negp, unsigned long *lvalp, int *valp,
+ int (*conv)(bool *negp, unsigned long *lvalp, int *valp,
int write, void *data),
void *data)
{
-#define TMPBUFLEN 21
- int *i, vleft, first = 1, neg;
- unsigned long lval;
- size_t left, len;
+ int *i, vleft, first = 1, err = 0;
+ unsigned long page = 0;
+ size_t left;
+ char *kbuf;
- char buf[TMPBUFLEN], *p;
- char __user *s = buffer;
-
- if (!tbl_data || !table->maxlen || !*lenp ||
- (*ppos && !write)) {
+ if (!tbl_data || !table->maxlen || !*lenp || (*ppos && !write)) {
*lenp = 0;
return 0;
}
@@ -2088,89 +2241,69 @@ static int __do_proc_dointvec(void *tbl_data, struct ctl_table *table,
if (!conv)
conv = do_proc_dointvec_conv;
+ if (write) {
+ if (left > PAGE_SIZE - 1)
+ left = PAGE_SIZE - 1;
+ page = __get_free_page(GFP_TEMPORARY);
+ kbuf = (char *) page;
+ if (!kbuf)
+ return -ENOMEM;
+ if (copy_from_user(kbuf, buffer, left)) {
+ err = -EFAULT;
+ goto free;
+ }
+ kbuf[left] = 0;
+ }
+
for (; left && vleft--; i++, first=0) {
- if (write) {
- while (left) {
- char c;
- if (get_user(c, s))
- return -EFAULT;
- if (!isspace(c))
- break;
- left--;
- s++;
- }
- if (!left)
- break;
- neg = 0;
- len = left;
- if (len > sizeof(buf) - 1)
- len = sizeof(buf) - 1;
- if (copy_from_user(buf, s, len))
- return -EFAULT;
- buf[len] = 0;
- p = buf;
- if (*p == '-' && left > 1) {
- neg = 1;
- p++;
- }
- if (*p < '0' || *p > '9')
- break;
+ unsigned long lval;
+ bool neg;
- lval = simple_strtoul(p, &p, 0);
+ if (write) {
+ left -= proc_skip_spaces(&kbuf);
- len = p-buf;
- if ((len < left) && *p && !isspace(*p))
+ err = proc_get_long(&kbuf, &left, &lval, &neg,
+ proc_wspace_sep,
+ sizeof(proc_wspace_sep), NULL);
+ if (err)
break;
- s += len;
- left -= len;
-
- if (conv(&neg, &lval, i, 1, data))
+ if (conv(&neg, &lval, i, 1, data)) {
+ err = -EINVAL;
break;
+ }
} else {
- p = buf;
+ if (conv(&neg, &lval, i, 0, data)) {
+ err = -EINVAL;
+ break;
+ }
if (!first)
- *p++ = '\t';
-
- if (conv(&neg, &lval, i, 0, data))
+ err = proc_put_char(&buffer, &left, '\t');
+ if (err)
+ break;
+ err = proc_put_long(&buffer, &left, lval, neg);
+ if (err)
break;
-
- sprintf(p, "%s%lu", neg ? "-" : "", lval);
- len = strlen(buf);
- if (len > left)
- len = left;
- if(copy_to_user(s, buf, len))
- return -EFAULT;
- left -= len;
- s += len;
}
}
- if (!write && !first && left) {
- if(put_user('\n', s))
- return -EFAULT;
- left--, s++;
- }
+ if (!write && !first && left && !err)
+ err = proc_put_char(&buffer, &left, '\n');
+ if (write && !err)
+ left -= proc_skip_spaces(&kbuf);
+free:
if (write) {
- while (left) {
- char c;
- if (get_user(c, s++))
- return -EFAULT;
- if (!isspace(c))
- break;
- left--;
- }
+ free_page(page);
+ if (first)
+ return err ? : -EINVAL;
}
- if (write && first)
- return -EINVAL;
*lenp -= left;
*ppos += *lenp;
- return 0;
-#undef TMPBUFLEN
+ return err;
}
static int do_proc_dointvec(struct ctl_table *table, int write,
void __user *buffer, size_t *lenp, loff_t *ppos,
- int (*conv)(int *negp, unsigned long *lvalp, int *valp,
+ int (*conv)(bool *negp, unsigned long *lvalp, int *valp,
int write, void *data),
void *data)
{
@@ -2238,8 +2371,8 @@ struct do_proc_dointvec_minmax_conv_param {
int *max;
};
-static int do_proc_dointvec_minmax_conv(int *negp, unsigned long *lvalp,
- int *valp,
+static int do_proc_dointvec_minmax_conv(bool *negp, unsigned long *lvalp,
+ int *valp,
int write, void *data)
{
struct do_proc_dointvec_minmax_conv_param *param = data;
@@ -2252,10 +2385,10 @@ static int do_proc_dointvec_minmax_conv(int *negp, unsigned long *lvalp,
} else {
int val = *valp;
if (val < 0) {
- *negp = -1;
+ *negp = true;
*lvalp = (unsigned long)-val;
} else {
- *negp = 0;
+ *negp = false;
*lvalp = (unsigned long)val;
}
}
@@ -2295,102 +2428,78 @@ static int __do_proc_doulongvec_minmax(void *data, struct ctl_table *table, int
unsigned long convmul,
unsigned long convdiv)
{
-#define TMPBUFLEN 21
- unsigned long *i, *min, *max, val;
- int vleft, first=1, neg;
- size_t len, left;
- char buf[TMPBUFLEN], *p;
- char __user *s = buffer;
-
- if (!data || !table->maxlen || !*lenp ||
- (*ppos && !write)) {
+ unsigned long *i, *min, *max;
+ int vleft, first = 1, err = 0;
+ unsigned long page = 0;
+ size_t left;
+ char *kbuf;
+
+ if (!data || !table->maxlen || !*lenp || (*ppos && !write)) {
*lenp = 0;
return 0;
}
-
+
i = (unsigned long *) data;
min = (unsigned long *) table->extra1;
max = (unsigned long *) table->extra2;
vleft = table->maxlen / sizeof(unsigned long);
left = *lenp;
-
+
+ if (write) {
+ if (left > PAGE_SIZE - 1)
+ left = PAGE_SIZE - 1;
+ page = __get_free_page(GFP_TEMPORARY);
+ kbuf = (char *) page;
+ if (!kbuf)
+ return -ENOMEM;
+ if (copy_from_user(kbuf, buffer, left)) {
+ err = -EFAULT;
+ goto free;
+ }
+ kbuf[left] = 0;
+ }
+
for (; left && vleft--; i++, min++, max++, first=0) {
+ unsigned long val;
+
if (write) {
- while (left) {
- char c;
- if (get_user(c, s))
- return -EFAULT;
- if (!isspace(c))
- break;
- left--;
- s++;
- }
- if (!left)
- break;
- neg = 0;
- len = left;
- if (len > TMPBUFLEN-1)
- len = TMPBUFLEN-1;
- if (copy_from_user(buf, s, len))
- return -EFAULT;
- buf[len] = 0;
- p = buf;
- if (*p == '-' && left > 1) {
- neg = 1;
- p++;
- }
- if (*p < '0' || *p > '9')
- break;
- val = simple_strtoul(p, &p, 0) * convmul / convdiv ;
- len = p-buf;
- if ((len < left) && *p && !isspace(*p))
+ bool neg;
+
+ left -= proc_skip_spaces(&kbuf);
+
+ err = proc_get_long(&kbuf, &left, &val, &neg,
+ proc_wspace_sep,
+ sizeof(proc_wspace_sep), NULL);
+ if (err)
break;
if (neg)
- val = -val;
- s += len;
- left -= len;
-
- if(neg)
continue;
if ((min && val < *min) || (max && val > *max))
continue;
*i = val;
} else {
- p = buf;
+ val = convdiv * (*i) / convmul;
if (!first)
- *p++ = '\t';
- sprintf(p, "%lu", convdiv * (*i) / convmul);
- len = strlen(buf);
- if (len > left)
- len = left;
- if(copy_to_user(s, buf, len))
- return -EFAULT;
- left -= len;
- s += len;
+ err = proc_put_char(&buffer, &left, '\t');
+ err = proc_put_long(&buffer, &left, val, false);
+ if (err)
+ break;
}
}
- if (!write && !first && left) {
- if(put_user('\n', s))
- return -EFAULT;
- left--, s++;
- }
+ if (!write && !first && left && !err)
+ err = proc_put_char(&buffer, &left, '\n');
+ if (write && !err)
+ left -= proc_skip_spaces(&kbuf);
+free:
if (write) {
- while (left) {
- char c;
- if (get_user(c, s++))
- return -EFAULT;
- if (!isspace(c))
- break;
- left--;
- }
+ free_page(page);
+ if (first)
+ return err ? : -EINVAL;
}
- if (write && first)
- return -EINVAL;
*lenp -= left;
*ppos += *lenp;
- return 0;
-#undef TMPBUFLEN
+ return err;
}
static int do_proc_doulongvec_minmax(struct ctl_table *table, int write,
@@ -2451,7 +2560,7 @@ int proc_doulongvec_ms_jiffies_minmax(struct ctl_table *table, int write,
}
-static int do_proc_dointvec_jiffies_conv(int *negp, unsigned long *lvalp,
+static int do_proc_dointvec_jiffies_conv(bool *negp, unsigned long *lvalp,
int *valp,
int write, void *data)
{
@@ -2463,10 +2572,10 @@ static int do_proc_dointvec_jiffies_conv(int *negp, unsigned long *lvalp,
int val = *valp;
unsigned long lval;
if (val < 0) {
- *negp = -1;
+ *negp = true;
lval = (unsigned long)-val;
} else {
- *negp = 0;
+ *negp = false;
lval = (unsigned long)val;
}
*lvalp = lval / HZ;
@@ -2474,7 +2583,7 @@ static int do_proc_dointvec_jiffies_conv(int *negp, unsigned long *lvalp,
return 0;
}
-static int do_proc_dointvec_userhz_jiffies_conv(int *negp, unsigned long *lvalp,
+static int do_proc_dointvec_userhz_jiffies_conv(bool *negp, unsigned long *lvalp,
int *valp,
int write, void *data)
{
@@ -2486,10 +2595,10 @@ static int do_proc_dointvec_userhz_jiffies_conv(int *negp, unsigned long *lvalp,
int val = *valp;
unsigned long lval;
if (val < 0) {
- *negp = -1;
+ *negp = true;
lval = (unsigned long)-val;
} else {
- *negp = 0;
+ *negp = false;
lval = (unsigned long)val;
}
*lvalp = jiffies_to_clock_t(lval);
@@ -2497,7 +2606,7 @@ static int do_proc_dointvec_userhz_jiffies_conv(int *negp, unsigned long *lvalp,
return 0;
}
-static int do_proc_dointvec_ms_jiffies_conv(int *negp, unsigned long *lvalp,
+static int do_proc_dointvec_ms_jiffies_conv(bool *negp, unsigned long *lvalp,
int *valp,
int write, void *data)
{
@@ -2507,10 +2616,10 @@ static int do_proc_dointvec_ms_jiffies_conv(int *negp, unsigned long *lvalp,
int val = *valp;
unsigned long lval;
if (val < 0) {
- *negp = -1;
+ *negp = true;
lval = (unsigned long)-val;
} else {
- *negp = 0;
+ *negp = false;
lval = (unsigned long)val;
}
*lvalp = jiffies_to_msecs(lval);
@@ -2607,6 +2716,157 @@ static int proc_do_cad_pid(struct ctl_table *table, int write,
return 0;
}
+/**
+ * proc_do_large_bitmap - read/write from/to a large bitmap
+ * @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
+ *
+ * The bitmap is stored at table->data and the bitmap length (in bits)
+ * in table->maxlen.
+ *
+ * We use a range comma separated format (e.g. 1,3-4,10-10) so that
+ * large bitmaps may be represented in a compact manner. Writing into
+ * the file will clear the bitmap then update it with the given input.
+ *
+ * Returns 0 on success.
+ */
+int proc_do_large_bitmap(struct ctl_table *table, int write,
+ void __user *buffer, size_t *lenp, loff_t *ppos)
+{
+ int err = 0;
+ bool first = 1;
+ size_t left = *lenp;
+ unsigned long bitmap_len = table->maxlen;
+ unsigned long *bitmap = (unsigned long *) table->data;
+ unsigned long *tmp_bitmap = NULL;
+ char tr_a[] = { '-', ',', '\n' }, tr_b[] = { ',', '\n', 0 }, c;
+
+ if (!bitmap_len || !left || (*ppos && !write)) {
+ *lenp = 0;
+ return 0;
+ }
+
+ if (write) {
+ unsigned long page = 0;
+ char *kbuf;
+
+ if (left > PAGE_SIZE - 1)
+ left = PAGE_SIZE - 1;
+
+ page = __get_free_page(GFP_TEMPORARY);
+ kbuf = (char *) page;
+ if (!kbuf)
+ return -ENOMEM;
+ if (copy_from_user(kbuf, buffer, left)) {
+ free_page(page);
+ return -EFAULT;
+ }
+ kbuf[left] = 0;
+
+ tmp_bitmap = kzalloc(BITS_TO_LONGS(bitmap_len) * sizeof(unsigned long),
+ GFP_KERNEL);
+ if (!tmp_bitmap) {
+ free_page(page);
+ return -ENOMEM;
+ }
+ proc_skip_char(&kbuf, &left, '\n');
+ while (!err && left) {
+ unsigned long val_a, val_b;
+ bool neg;
+
+ err = proc_get_long(&kbuf, &left, &val_a, &neg, tr_a,
+ sizeof(tr_a), &c);
+ if (err)
+ break;
+ if (val_a >= bitmap_len || neg) {
+ err = -EINVAL;
+ break;
+ }
+
+ val_b = val_a;
+ if (left) {
+ kbuf++;
+ left--;
+ }
+
+ if (c == '-') {
+ err = proc_get_long(&kbuf, &left, &val_b,
+ &neg, tr_b, sizeof(tr_b),
+ &c);
+ if (err)
+ break;
+ if (val_b >= bitmap_len || neg ||
+ val_a > val_b) {
+ err = -EINVAL;
+ break;
+ }
+ if (left) {
+ kbuf++;
+ left--;
+ }
+ }
+
+ while (val_a <= val_b)
+ set_bit(val_a++, tmp_bitmap);
+
+ first = 0;
+ proc_skip_char(&kbuf, &left, '\n');
+ }
+ free_page(page);
+ } else {
+ unsigned long bit_a, bit_b = 0;
+
+ while (left) {
+ bit_a = find_next_bit(bitmap, bitmap_len, bit_b);
+ if (bit_a >= bitmap_len)
+ break;
+ bit_b = find_next_zero_bit(bitmap, bitmap_len,
+ bit_a + 1) - 1;
+
+ if (!first) {
+ err = proc_put_char(&buffer, &left, ',');
+ if (err)
+ break;
+ }
+ err = proc_put_long(&buffer, &left, bit_a, false);
+ if (err)
+ break;
+ if (bit_a != bit_b) {
+ err = proc_put_char(&buffer, &left, '-');
+ if (err)
+ break;
+ err = proc_put_long(&buffer, &left, bit_b, false);
+ if (err)
+ break;
+ }
+
+ first = 0; bit_b++;
+ }
+ if (!err)
+ err = proc_put_char(&buffer, &left, '\n');
+ }
+
+ if (!err) {
+ if (write) {
+ if (*ppos)
+ bitmap_or(bitmap, bitmap, tmp_bitmap, bitmap_len);
+ else
+ memcpy(bitmap, tmp_bitmap,
+ BITS_TO_LONGS(bitmap_len) * sizeof(unsigned long));
+ }
+ kfree(tmp_bitmap);
+ *lenp -= left;
+ *ppos += *lenp;
+ return 0;
+ } else {
+ kfree(tmp_bitmap);
+ return err;
+ }
+}
+
#else /* CONFIG_PROC_FS */
int proc_dostring(struct ctl_table *table, int write,
generated by cgit v1.2.3 (git 2.46.0) at 2025-10-31 11:47:02 +0000