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authorGreg Kroah-Hartman <gregkh@linuxfoundation.org>2022-05-02 13:56:48 +0200
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2022-05-02 13:56:48 +0200
commit0e509f537f8ddd89f237e62f77818dbdbc8be395 (patch)
tree4e747a1cad81d0c085d435923366bcce30484bc8 /lib
parentf8ae07f4b8bfde0f33761e1a1aaee45a4e85e9d6 (diff)
parent672c0c5173427e6b3e2a9bbb7be51ceeec78093a (diff)
Merge 5.18-rc5 into driver-core-next
We need the kernfs/driver core fixes in here as well. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'lib')
-rw-r--r--lib/hexdump.c41
-rw-r--r--lib/strncpy_from_user.c2
-rw-r--r--lib/strnlen_user.c2
-rw-r--r--lib/xarray.c2
4 files changed, 35 insertions, 12 deletions
diff --git a/lib/hexdump.c b/lib/hexdump.c
index 9301578f98e8..06833d404398 100644
--- a/lib/hexdump.c
+++ b/lib/hexdump.c
@@ -22,15 +22,33 @@ EXPORT_SYMBOL(hex_asc_upper);
*
* hex_to_bin() converts one hex digit to its actual value or -1 in case of bad
* input.
+ *
+ * This function is used to load cryptographic keys, so it is coded in such a
+ * way that there are no conditions or memory accesses that depend on data.
+ *
+ * Explanation of the logic:
+ * (ch - '9' - 1) is negative if ch <= '9'
+ * ('0' - 1 - ch) is negative if ch >= '0'
+ * we "and" these two values, so the result is negative if ch is in the range
+ * '0' ... '9'
+ * we are only interested in the sign, so we do a shift ">> 8"; note that right
+ * shift of a negative value is implementation-defined, so we cast the
+ * value to (unsigned) before the shift --- we have 0xffffff if ch is in
+ * the range '0' ... '9', 0 otherwise
+ * we "and" this value with (ch - '0' + 1) --- we have a value 1 ... 10 if ch is
+ * in the range '0' ... '9', 0 otherwise
+ * we add this value to -1 --- we have a value 0 ... 9 if ch is in the range '0'
+ * ... '9', -1 otherwise
+ * the next line is similar to the previous one, but we need to decode both
+ * uppercase and lowercase letters, so we use (ch & 0xdf), which converts
+ * lowercase to uppercase
*/
-int hex_to_bin(char ch)
+int hex_to_bin(unsigned char ch)
{
- if ((ch >= '0') && (ch <= '9'))
- return ch - '0';
- ch = tolower(ch);
- if ((ch >= 'a') && (ch <= 'f'))
- return ch - 'a' + 10;
- return -1;
+ unsigned char cu = ch & 0xdf;
+ return -1 +
+ ((ch - '0' + 1) & (unsigned)((ch - '9' - 1) & ('0' - 1 - ch)) >> 8) +
+ ((cu - 'A' + 11) & (unsigned)((cu - 'F' - 1) & ('A' - 1 - cu)) >> 8);
}
EXPORT_SYMBOL(hex_to_bin);
@@ -45,10 +63,13 @@ EXPORT_SYMBOL(hex_to_bin);
int hex2bin(u8 *dst, const char *src, size_t count)
{
while (count--) {
- int hi = hex_to_bin(*src++);
- int lo = hex_to_bin(*src++);
+ int hi, lo;
- if ((hi < 0) || (lo < 0))
+ hi = hex_to_bin(*src++);
+ if (unlikely(hi < 0))
+ return -EINVAL;
+ lo = hex_to_bin(*src++);
+ if (unlikely(lo < 0))
return -EINVAL;
*dst++ = (hi << 4) | lo;
diff --git a/lib/strncpy_from_user.c b/lib/strncpy_from_user.c
index 08fc72d3ed16..6432b8c3e431 100644
--- a/lib/strncpy_from_user.c
+++ b/lib/strncpy_from_user.c
@@ -25,7 +25,7 @@
* hit it), 'max' is the address space maximum (and we return
* -EFAULT if we hit it).
*/
-static inline long do_strncpy_from_user(char *dst, const char __user *src,
+static __always_inline long do_strncpy_from_user(char *dst, const char __user *src,
unsigned long count, unsigned long max)
{
const struct word_at_a_time constants = WORD_AT_A_TIME_CONSTANTS;
diff --git a/lib/strnlen_user.c b/lib/strnlen_user.c
index bffa0ebf9f8b..feeb935a2299 100644
--- a/lib/strnlen_user.c
+++ b/lib/strnlen_user.c
@@ -20,7 +20,7 @@
* if it fits in a aligned 'long'. The caller needs to check
* the return value against "> max".
*/
-static inline long do_strnlen_user(const char __user *src, unsigned long count, unsigned long max)
+static __always_inline long do_strnlen_user(const char __user *src, unsigned long count, unsigned long max)
{
const struct word_at_a_time constants = WORD_AT_A_TIME_CONSTANTS;
unsigned long align, res = 0;
diff --git a/lib/xarray.c b/lib/xarray.c
index 4acc88ea7c21..54e646e8e6ee 100644
--- a/lib/xarray.c
+++ b/lib/xarray.c
@@ -207,6 +207,8 @@ static void *xas_descend(struct xa_state *xas, struct xa_node *node)
if (xa_is_sibling(entry)) {
offset = xa_to_sibling(entry);
entry = xa_entry(xas->xa, node, offset);
+ if (node->shift && xa_is_node(entry))
+ entry = XA_RETRY_ENTRY;
}
xas->xa_offset = offset;