summaryrefslogtreecommitdiff
path: root/lib/string.c
diff options
context:
space:
mode:
authorGreg Kroah-Hartman <gregkh@google.com>2021-02-23 14:48:49 +0100
committerGreg Kroah-Hartman <gregkh@google.com>2021-02-23 14:48:49 +0100
commit4fd124d1546d8a4300e1cdd637818af038e29fb2 (patch)
tree507aa781e0f77f04c1856d79623a9cabd61033ba /lib/string.c
parent831b1199b5e3105a15c3a12c7bd03ea45320ed01 (diff)
parent312b5d65a03db01974224c76481c0db1786c41ae (diff)
Merge 4.4.258 into android-4.4-p
Changes in 4.4.258 tracing: Do not count ftrace events in top level enable output fgraph: Initialize tracing_graph_pause at task creation af_key: relax availability checks for skb size calculation iwlwifi: pcie: add a NULL check in iwl_pcie_txq_unmap iwlwifi: mvm: guard against device removal in reprobe SUNRPC: Move simple_get_bytes and simple_get_netobj into private header SUNRPC: Handle 0 length opaque XDR object data properly lib/string: Add strscpy_pad() function include/trace/events/writeback.h: fix -Wstringop-truncation warnings memcg: fix a crash in wb_workfn when a device disappears squashfs: add more sanity checks in id lookup squashfs: add more sanity checks in inode lookup squashfs: add more sanity checks in xattr id lookup memblock: do not start bottom-up allocations with kernel_end netfilter: xt_recent: Fix attempt to update deleted entry h8300: fix PREEMPTION build, TI_PRE_COUNT undefined usb: dwc3: ulpi: fix checkpatch warning usb: dwc3: ulpi: Replace CPU-based busyloop with Protocol-based one net: watchdog: hold device global xmit lock during tx disable vsock: fix locking in vsock_shutdown() x86/build: Disable CET instrumentation in the kernel for 32-bit too trace: Use -mcount-record for dynamic ftrace tracing: Fix SKIP_STACK_VALIDATION=1 build due to bad merge with -mrecord-mcount tracing: Avoid calling cc-option -mrecord-mcount for every Makefile Xen/x86: don't bail early from clear_foreign_p2m_mapping() Xen/x86: also check kernel mapping in set_foreign_p2m_mapping() Xen/gntdev: correct dev_bus_addr handling in gntdev_map_grant_pages() Xen/gntdev: correct error checking in gntdev_map_grant_pages() xen/arm: don't ignore return errors from set_phys_to_machine xen-blkback: don't "handle" error by BUG() xen-netback: don't "handle" error by BUG() xen-scsiback: don't "handle" error by BUG() xen-blkback: fix error handling in xen_blkbk_map() scsi: qla2xxx: Fix crash during driver load on big endian machines kvm: check tlbs_dirty directly Linux 4.4.258 Signed-off-by: Greg Kroah-Hartman <gregkh@google.com> Change-Id: Ie1125773ccbc457f93c639c420dedf2c38a5e65a
Diffstat (limited to 'lib/string.c')
-rw-r--r--lib/string.c47
1 files changed, 40 insertions, 7 deletions
diff --git a/lib/string.c b/lib/string.c
index 7f4baad6fb19..4351ec43cd6b 100644
--- a/lib/string.c
+++ b/lib/string.c
@@ -157,11 +157,9 @@ EXPORT_SYMBOL(strlcpy);
* @src: Where to copy the string from
* @count: Size of destination buffer
*
- * Copy the string, or as much of it as fits, into the dest buffer.
- * The routine returns the number of characters copied (not including
- * the trailing NUL) or -E2BIG if the destination buffer wasn't big enough.
- * The behavior is undefined if the string buffers overlap.
- * The destination buffer is always NUL terminated, unless it's zero-sized.
+ * Copy the string, or as much of it as fits, into the dest buffer. The
+ * behavior is undefined if the string buffers overlap. The destination
+ * buffer is always NUL terminated, unless it's zero-sized.
*
* Preferred to strlcpy() since the API doesn't require reading memory
* from the src string beyond the specified "count" bytes, and since
@@ -171,8 +169,10 @@ EXPORT_SYMBOL(strlcpy);
*
* Preferred to strncpy() since it always returns a valid string, and
* doesn't unnecessarily force the tail of the destination buffer to be
- * zeroed. If the zeroing is desired, it's likely cleaner to use strscpy()
- * with an overflow test, then just memset() the tail of the dest buffer.
+ * zeroed. If zeroing is desired please use strscpy_pad().
+ *
+ * Return: The number of characters copied (not including the trailing
+ * %NUL) or -E2BIG if the destination buffer wasn't big enough.
*/
ssize_t strscpy(char *dest, const char *src, size_t count)
{
@@ -259,6 +259,39 @@ char *stpcpy(char *__restrict__ dest, const char *__restrict__ src)
}
EXPORT_SYMBOL(stpcpy);
+/**
+ * strscpy_pad() - Copy a C-string into a sized buffer
+ * @dest: Where to copy the string to
+ * @src: Where to copy the string from
+ * @count: Size of destination buffer
+ *
+ * Copy the string, or as much of it as fits, into the dest buffer. The
+ * behavior is undefined if the string buffers overlap. The destination
+ * buffer is always %NUL terminated, unless it's zero-sized.
+ *
+ * If the source string is shorter than the destination buffer, zeros
+ * the tail of the destination buffer.
+ *
+ * For full explanation of why you may want to consider using the
+ * 'strscpy' functions please see the function docstring for strscpy().
+ *
+ * Return: The number of characters copied (not including the trailing
+ * %NUL) or -E2BIG if the destination buffer wasn't big enough.
+ */
+ssize_t strscpy_pad(char *dest, const char *src, size_t count)
+{
+ ssize_t written;
+
+ written = strscpy(dest, src, count);
+ if (written < 0 || written == count - 1)
+ return written;
+
+ memset(dest + written + 1, 0, count - written - 1);
+
+ return written;
+}
+EXPORT_SYMBOL(strscpy_pad);
+
#ifndef __HAVE_ARCH_STRCAT
/**
* strcat - Append one %NUL-terminated string to another