Revert "lib: string: Fix strlcpy return value", fix callers

Both the Linux kernel and libbsd agree that strlcpy() should always
return strlen(src) and not include the NUL termination. The incorrect
U-Boot implementation makes it impossible to check the return value for
truncation, and breaks code written with the usual implementation in
mind (for example, fdtdec_add_reserved_memory() was subtly broken).

I reviewed all callers of strlcpy() and strlcat() and fixed them
according to my understanding of the intended function.

This reverts commit d3358ecc54be0bc3b4dd11f7a63eab0a2842f772 and adds
related fixes.

Fixes: d3358ecc54be ("lib: string: Fix strlcpy return value")
Signed-off-by: Matthias Schiffer <matthias.schiffer@ew.tq-group.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Sean Anderson <sean.anderson@seco.com>

diff --git a/board/amlogic/vim3/vim3.c b/board/amlogic/vim3/vim3.c
index fcd60ab1e058e53ceb0cd84e34cfacda3741a934..8bdfb302f7283e3939c57c146d12eafcf92baf01 100644 (file)
--- a/board/amlogic/vim3/vim3.c
+++ b/board/amlogic/vim3/vim3.c
@@ -104,8 +104,8 @@ int meson_ft_board_setup(void *blob, struct bd_info *bd)
                }
 
                /* Update PHY names (mandatory to disable USB3.0) */
-               len = strlcpy(data, "usb2-phy0", 32);
-               len += strlcpy(&data[len], "usb2-phy1", 32 - len);
+               len = strlcpy(data, "usb2-phy0", 32) + 1;
+               len += strlcpy(&data[len], "usb2-phy1", 32 - len) + 1;
                ret = fdt_setprop(blob, node, "phy-names", data, len);
                if (ret < 0) {
                        printf("vim3: failed to update usb phy names property (%d)\n", ret);
@@ -132,7 +132,7 @@ int meson_ft_board_setup(void *blob, struct bd_info *bd)
                }
 
                /* Enable PCIe */
-               len = strlcpy(data, "okay", 32);
+               len = strlcpy(data, "okay", 32) + 1;
                ret = fdt_setprop(blob, node, "status", data, len);
                if (ret < 0) {
                        printf("vim3: failed to enable pcie node (%d)\n", ret);

diff --git a/drivers/fastboot/fb_getvar.c b/drivers/fastboot/fb_getvar.c
index dd3475e0a8bd1afefe61a91534b0a8d1fee2bc38..d9f0f07b2bcd2490f7f58982f224ccd2091b571f 100644 (file)
--- a/drivers/fastboot/fb_getvar.c
+++ b/drivers/fastboot/fb_getvar.c
@@ -183,7 +183,7 @@ static void __maybe_unused getvar_has_slot(char *part_name, char *response)
 
        /* part_name_wslot = part_name + "_a" */
        len = strlcpy(part_name_wslot, part_name, PART_NAME_LEN - 3);
-       if (len > PART_NAME_LEN - 3)
+       if (len >= PART_NAME_LEN - 3)
                goto fail;
        strcat(part_name_wslot, "_a");
 

diff --git a/lib/string.c b/lib/string.c
index ecea755f40535277ab407dbfa897ce8b7272a5a0..f2c61471288d179bfdabe4d3729013521521feca 100644 (file)
--- a/lib/string.c
+++ b/lib/string.c
@@ -116,20 +116,18 @@ char * strncpy(char * dest,const char *src,size_t count)
  * of course, the buffer size is zero). It does not pad
  * out the result like strncpy() does.
  *
- * Return: the number of bytes copied
+ * Return: strlen(src)
  */
 size_t strlcpy(char *dest, const char *src, size_t size)
 {
-       if (size) {
-               size_t srclen = strlen(src);
-               size_t len = (srclen >= size) ? size - 1 : srclen;
+       size_t ret = strlen(src);
 
+       if (size) {
+               size_t len = (ret >= size) ? size - 1 : ret;
                memcpy(dest, src, len);
                dest[len] = '\0';
-               return len + 1;
        }
-
-       return 0;
+       return ret;
 }
 #endif
 
@@ -191,6 +189,8 @@ char * strncat(char *dest, const char *src, size_t count)
  * Compatible with *BSD: the result is always a valid NUL-terminated string that
  * fits in the buffer (unless, of course, the buffer size is zero). It does not
  * write past @size like strncat() does.
+ *
+ * Return: min(strlen(dest), size) + strlen(src)
  */
 size_t strlcat(char *dest, const char *src, size_t size)
 {

diff --git a/test/lib/strlcat.c b/test/lib/strlcat.c
index a0ec037388bf9acfb976df0e16fc06726d36898a..d8453fe78e2c01c4ce192684f4a1e974a5cae221 100644 (file)
--- a/test/lib/strlcat.c
+++ b/test/lib/strlcat.c
@@ -43,11 +43,11 @@ static int do_test_strlcat(struct unit_test_state *uts, int line, size_t align1,
                s2[i] = 32 + 23 * i % (127 - 32);
        s2[len2 - 1] = '\0';
 
-       expected = len2 < n ? min(len1 + len2 - 1, n) : n;
+       expected = min(strlen(s2), n) + strlen(s1);
        actual = strlcat(s2, s1, n);
        if (expected != actual) {
                ut_failf(uts, __FILE__, line, __func__,
-                        "strlcat(s2, s1, 2) == len2 < n ? min(len1 + len2, n) : n",
+                        "strlcat(s2, s1, n) == min(len2, n) + len1",
                         "Expected %#zx (%zd), got %#zx (%zd)",
                         expected, expected, actual, actual);
                return CMD_RET_FAILURE;