Commit 2a18a550 authored Jun 16, 2021 by Kees Cook Committed by Vasily Gorbik Jun 28, 2021

s390/zcrypt: Switch to flexible array member



In preparation for FORTIFY_SOURCE performing compile-time and run-time
field bounds checking for memcpy(), memmove(), and memset(), avoid
intentionally reading/writing across neighboring array fields.

Switch from zero-element arrays to flexible arrays so the compiler will
perform appropriate bounds checking, avoiding these future warnings:

In function '__fortify_memcpy',
    inlined from 'cca_sec2protkey' at drivers/s390/crypto/zcrypt_ccamisc.c:645:2:
./include/linux/fortify-string.h:244:4: error: call to '__write_overflow_field' declared with attribute error: detected write beyond size of field (1st parameter)

In function '__fortify_memcpy',
    inlined from 'cca_clr2seckey' at drivers/s390/crypto/zcrypt_ccamisc.c:568:3:
./include/linux/fortify-string.h:246:4: error: call to '__read_overflow2_field' declared with attribute error: detected read beyond size of field (2nd parameter)

In function '__fortify_memcpy',
    inlined from 'cca_genseckey' at drivers/s390/crypto/zcrypt_ccamisc.c:429:2:
./include/linux/fortify-string.h:246:4: error: call to '__read_overflow2_field' declared with attribute error: detected read beyond size of field (2nd parameter)

Signed-off-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20210616201903.1245949-1-keescook@chromium.org


Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>

parent c74d3c18

drivers/s390/crypto/zcrypt_ccamisc.c

+3 −3

Original line number	Diff line number	Diff line
		@@ -330,7 +330,7 @@ int cca_genseckey(u16 cardnr, u16 domain,
		struct {
		u16 toklen;
		u16 tokattr;
		u8 tok[0];
		u8 tok[];
		/* ... some more data ... */
		} keyblock;
		} lv3;
		@@ -471,7 +471,7 @@ int cca_clr2seckey(u16 cardnr, u16 domain, u32 keybitsize,
		struct {
		u16 toklen;
		u16 tokattr;
		u8 tok[0];
		u8 tok[];
		/* ... some more data ... */
		} keyblock;
		} lv3;
		@@ -596,7 +596,7 @@ int cca_sec2protkey(u16 cardnr, u16 domain,
		u16 len;
		u16 attr_len;
		u16 attr_flags;
		u8 token[0]; /* cca secure key token */
		u8 token[]; /* cca secure key token */
		} lv2;
		} __packed * preqparm;
		struct uskrepparm {