From: Gavin Shan Date: Mon, 14 Oct 2024 00:47:24 +0000 (+1000) Subject: firmware: arm_ffa: Avoid string-fortify warning caused by memcpy() X-Git-Tag: v6.12-rc4~35^2~1^2 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=b0798838418abe996d9b618d341d865462264cbe;p=thirdparty%2Fkernel%2Flinux.git firmware: arm_ffa: Avoid string-fortify warning caused by memcpy() Copying from a 144 byte structure arm_smccc_1_2_regs at an offset of 32 into an 112 byte struct ffa_send_direct_data2 causes a compile-time warning: | In file included from drivers/firmware/arm_ffa/driver.c:25: | In function 'fortify_memcpy_chk', | inlined from 'ffa_msg_send_direct_req2' at drivers/firmware/arm_ffa/driver.c:504:3: | include/linux/fortify-string.h:580:4: warning: call to '__read_overflow2_field' | declared with 'warning' attribute: detected read beyond size of field | (2nd parameter); maybe use struct_group()? [-Wattribute-warning] | __read_overflow2_field(q_size_field, size); Fix it by not passing a plain buffer to memcpy() to avoid the overflow warning. Fixes: aaef3bc98129 ("firmware: arm_ffa: Add support for FFA_MSG_SEND_DIRECT_{REQ,RESP}2") Signed-off-by: Gavin Shan Message-Id: <20241014004724.991353-1-gshan@redhat.com> Signed-off-by: Sudeep Holla --- diff --git a/drivers/firmware/arm_ffa/driver.c b/drivers/firmware/arm_ffa/driver.c index 8dd81db9b071e..b14cbdae94e82 100644 --- a/drivers/firmware/arm_ffa/driver.c +++ b/drivers/firmware/arm_ffa/driver.c @@ -501,7 +501,7 @@ static int ffa_msg_send_direct_req2(u16 src_id, u16 dst_id, const uuid_t *uuid, return ffa_to_linux_errno((int)ret.a2); if (ret.a0 == FFA_MSG_SEND_DIRECT_RESP2) { - memcpy(data, &ret.a4, sizeof(*data)); + memcpy(data, (void *)&ret + offsetof(ffa_value_t, a4), sizeof(*data)); return 0; }