lib/siphash.c: mark expected switch fall-throughs

In preparation to enabling -Wimplicit-fallthrough, mark switch cases
where we are expecting to fall through.

This patch aims to suppress up to 18 missing-break-in-switch false
positives on some architectures.

Cc: Gustavo A. R. Silva <gustavo@embeddedor.com>
Cc: Kees Cook <keescook@chromium.org>
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Reviewed-by: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/lib/siphash.c b/lib/siphash.c
index 3ae58b4edad61527317f6a2b68f0343f8a654683..c47bb6ff21499780b125543eccc3d4406787bf5a 100644 (file)
--- a/lib/siphash.c
+++ b/lib/siphash.c
@@ -68,11 +68,11 @@ u64 __siphash_aligned(const void *data, size_t len, const siphash_key_t *key)
                                                  bytemask_from_count(left)));
 #else
        switch (left) {
-       case 7: b |= ((u64)end[6]) << 48;
-       case 6: b |= ((u64)end[5]) << 40;
-       case 5: b |= ((u64)end[4]) << 32;
+       case 7: b |= ((u64)end[6]) << 48; /* fall through */
+       case 6: b |= ((u64)end[5]) << 40; /* fall through */
+       case 5: b |= ((u64)end[4]) << 32; /* fall through */
        case 4: b |= le32_to_cpup(data); break;
-       case 3: b |= ((u64)end[2]) << 16;
+       case 3: b |= ((u64)end[2]) << 16; /* fall through */
        case 2: b |= le16_to_cpup(data); break;
        case 1: b |= end[0];
        }
@@ -101,11 +101,11 @@ u64 __siphash_unaligned(const void *data, size_t len, const siphash_key_t *key)
                                                  bytemask_from_count(left)));
 #else
        switch (left) {
-       case 7: b |= ((u64)end[6]) << 48;
-       case 6: b |= ((u64)end[5]) << 40;
-       case 5: b |= ((u64)end[4]) << 32;
+       case 7: b |= ((u64)end[6]) << 48; /* fall through */
+       case 6: b |= ((u64)end[5]) << 40; /* fall through */
+       case 5: b |= ((u64)end[4]) << 32; /* fall through */
        case 4: b |= get_unaligned_le32(end); break;
-       case 3: b |= ((u64)end[2]) << 16;
+       case 3: b |= ((u64)end[2]) << 16; /* fall through */
        case 2: b |= get_unaligned_le16(end); break;
        case 1: b |= end[0];
        }
@@ -268,11 +268,11 @@ u32 __hsiphash_aligned(const void *data, size_t len, const hsiphash_key_t *key)
                                                  bytemask_from_count(left)));
 #else
        switch (left) {
-       case 7: b |= ((u64)end[6]) << 48;
-       case 6: b |= ((u64)end[5]) << 40;
-       case 5: b |= ((u64)end[4]) << 32;
+       case 7: b |= ((u64)end[6]) << 48; /* fall through */
+       case 6: b |= ((u64)end[5]) << 40; /* fall through */
+       case 5: b |= ((u64)end[4]) << 32; /* fall through */
        case 4: b |= le32_to_cpup(data); break;
-       case 3: b |= ((u64)end[2]) << 16;
+       case 3: b |= ((u64)end[2]) << 16; /* fall through */
        case 2: b |= le16_to_cpup(data); break;
        case 1: b |= end[0];
        }
@@ -301,11 +301,11 @@ u32 __hsiphash_unaligned(const void *data, size_t len,
                                                  bytemask_from_count(left)));
 #else
        switch (left) {
-       case 7: b |= ((u64)end[6]) << 48;
-       case 6: b |= ((u64)end[5]) << 40;
-       case 5: b |= ((u64)end[4]) << 32;
+       case 7: b |= ((u64)end[6]) << 48; /* fall through */
+       case 6: b |= ((u64)end[5]) << 40; /* fall through */
+       case 5: b |= ((u64)end[4]) << 32; /* fall through */
        case 4: b |= get_unaligned_le32(end); break;
-       case 3: b |= ((u64)end[2]) << 16;
+       case 3: b |= ((u64)end[2]) << 16; /* fall through */
        case 2: b |= get_unaligned_le16(end); break;
        case 1: b |= end[0];
        }
@@ -431,7 +431,7 @@ u32 __hsiphash_aligned(const void *data, size_t len, const hsiphash_key_t *key)
                v0 ^= m;
        }
        switch (left) {
-       case 3: b |= ((u32)end[2]) << 16;
+       case 3: b |= ((u32)end[2]) << 16; /* fall through */
        case 2: b |= le16_to_cpup(data); break;
        case 1: b |= end[0];
        }
@@ -454,7 +454,7 @@ u32 __hsiphash_unaligned(const void *data, size_t len,
                v0 ^= m;
        }
        switch (left) {
-       case 3: b |= ((u32)end[2]) << 16;
+       case 3: b |= ((u32)end[2]) << 16; /* fall through */
        case 2: b |= get_unaligned_le16(end); break;
        case 1: b |= end[0];
        }