diff options
Diffstat (limited to 'src/interface')
| -rw-r--r-- | src/interface/efi/efi_snp.c | 22 |
1 files changed, 9 insertions, 13 deletions
diff --git a/src/interface/efi/efi_snp.c b/src/interface/efi/efi_snp.c index 5c3592e5..263a25ac 100644 --- a/src/interface/efi/efi_snp.c +++ b/src/interface/efi/efi_snp.c @@ -710,7 +710,7 @@ efi_snp_receive ( EFI_SIMPLE_NETWORK_PROTOCOL *snp, const void *iob_ll_src; uint16_t iob_net_proto; unsigned int iob_flags; - size_t max_len; + size_t copy_len; int rc; DBGC2 ( snpdev, "SNPDEV %p RECEIVE %p(+%lx)", snpdev, data, @@ -732,19 +732,15 @@ efi_snp_receive ( EFI_SIMPLE_NETWORK_PROTOCOL *snp, } DBGC2 ( snpdev, "+%zx\n", iob_len ( iobuf ) ); - /* Check buffer length */ - max_len = *len; - *len = iob_len ( iobuf ); - if ( *len > max_len ) { - rc = -ERANGE; - goto out_too_long; - } - /* Dequeue packet */ list_del ( &iobuf->list ); - /* Return packet to caller */ - memcpy ( data, iobuf->data, iob_len ( iobuf ) ); + /* Return packet to caller, truncating to buffer length */ + copy_len = iob_len ( iobuf ); + if ( copy_len > *len ) + copy_len = *len; + memcpy ( data, iobuf->data, copy_len ); + *len = iob_len ( iobuf ); /* Attempt to decode link-layer header */ if ( ( rc = ll_protocol->pull ( snpdev->netdev, iobuf, &iob_ll_dest, @@ -765,11 +761,11 @@ efi_snp_receive ( EFI_SIMPLE_NETWORK_PROTOCOL *snp, if ( net_proto ) *net_proto = ntohs ( iob_net_proto ); - rc = 0; + /* Check buffer length */ + rc = ( ( copy_len == *len ) ? 0 : -ERANGE ); out_bad_ll_header: free_iob ( iobuf ); - out_too_long: out_no_packet: return EFIRC ( rc ); } |