Hi Ying, On 22/05/19 7:58 PM, Ying Xue wrote: > On 5/20/19 11:45 AM, Chris Packham wrote: >> TLV_SET is called with a data pointer and a len parameter that tells us >> how many bytes are pointed to by data. When invoking memcpy() we need >> to careful to only copy len bytes. >> >> Previously we would copy TLV_LENGTH(len) bytes which would copy an extra >> 4 bytes past the end of the data pointer which newer GCC versions >> complain about. >> >> In file included from test.c:17: >> In function 'TLV_SET', >> inlined from 'test' at test.c:186:5: >> /usr/include/linux/tipc_config.h:317:3: >> warning: 'memcpy' forming offset [33, 36] is out of the bounds [0, 32] >> of object 'bearer_name' with type 'char[32]' [-Warray-bounds] >> memcpy(TLV_DATA(tlv_ptr), data, tlv_len); >> ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ >> test.c: In function 'test': >> test.c::161:10: note: >> 'bearer_name' declared here >> char bearer_name[TIPC_MAX_BEARER_NAME]; >> ^~~~~~~~~~~ >> >> We still want to ensure any padding bytes at the end are initialised, do >> this with a explicit memset() rather than copy bytes past the end of >> data. Apply the same logic to TCM_SET. >> >> Signed-off-by: Chris Packham <chris.pack...@alliedtelesis.co.nz> > > Acked-by: Ying Xue <ying....@windriver.com> > > > But please make the same changes in usr/include/linux/tipc_config.h >
I don't understand this comment. There is no usr/include in the kernel source. On most distros that is generated from include/uapi in the kernel source and packaged as part of libc or a kernel-headers package. So once this patch is accepted and makes it into the distros /usr/include/linux/tipc_config.h will have this fix. Adding Cc: stable might help get it there sooner. But I wanted to get it reviewed/accepted first. >> --- >> >> Changes in v2: >> - Ensure padding bytes are initialised in both TLV_SET and TCM_SET >> >> include/uapi/linux/tipc_config.h | 10 +++++++--- >> 1 file changed, 7 insertions(+), 3 deletions(-) >> >> diff --git a/include/uapi/linux/tipc_config.h >> b/include/uapi/linux/tipc_config.h >> index 4b2c93b1934c..4955e1a9f1bc 100644 >> --- a/include/uapi/linux/tipc_config.h >> +++ b/include/uapi/linux/tipc_config.h >> @@ -307,8 +307,10 @@ static inline int TLV_SET(void *tlv, __u16 type, void >> *data, __u16 len) >> tlv_ptr = (struct tlv_desc *)tlv; >> tlv_ptr->tlv_type = htons(type); >> tlv_ptr->tlv_len = htons(tlv_len); >> - if (len && data) >> - memcpy(TLV_DATA(tlv_ptr), data, tlv_len); >> + if (len && data) { >> + memcpy(TLV_DATA(tlv_ptr), data, len); >> + memset(TLV_DATA(tlv_ptr) + len, 0, TLV_SPACE(len) - tlv_len); >> + } >> return TLV_SPACE(len); >> } >> >> @@ -405,8 +407,10 @@ static inline int TCM_SET(void *msg, __u16 cmd, __u16 >> flags, >> tcm_hdr->tcm_len = htonl(msg_len); >> tcm_hdr->tcm_type = htons(cmd); >> tcm_hdr->tcm_flags = htons(flags); >> - if (data_len && data) >> + if (data_len && data) { >> memcpy(TCM_DATA(msg), data, data_len); >> + memset(TCM_DATA(msg) + data_len, 0, TCM_SPACE(data_len) - >> msg_len); >> + } >> return TCM_SPACE(data_len); >> } >> >> >