| From foo@baz Fri Sep 15 10:03:45 PDT 2017 |
| From: Arnd Bergmann <arnd@arndb.de> |
| Date: Wed, 23 Aug 2017 15:59:49 +0200 |
| Subject: qlge: avoid memcpy buffer overflow |
| |
| From: Arnd Bergmann <arnd@arndb.de> |
| |
| |
| [ Upstream commit e58f95831e7468d25eb6e41f234842ecfe6f014f ] |
| |
| gcc-8.0.0 (snapshot) points out that we copy a variable-length string |
| into a fixed length field using memcpy() with the destination length, |
| and that ends up copying whatever follows the string: |
| |
| inlined from 'ql_core_dump' at drivers/net/ethernet/qlogic/qlge/qlge_dbg.c:1106:2: |
| drivers/net/ethernet/qlogic/qlge/qlge_dbg.c:708:2: error: 'memcpy' reading 15 bytes from a region of size 14 [-Werror=stringop-overflow=] |
| memcpy(seg_hdr->description, desc, (sizeof(seg_hdr->description)) - 1); |
| |
| Changing it to use strncpy() will instead zero-pad the destination, |
| which seems to be the right thing to do here. |
| |
| The bug is probably harmless, but it seems like a good idea to address |
| it in stable kernels as well, if only for the purpose of building with |
| gcc-8 without warnings. |
| |
| Fixes: a61f80261306 ("qlge: Add ethtool register dump function.") |
| Signed-off-by: Arnd Bergmann <arnd@arndb.de> |
| Signed-off-by: David S. Miller <davem@davemloft.net> |
| Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
| --- |
| drivers/net/ethernet/qlogic/qlge/qlge_dbg.c | 2 +- |
| 1 file changed, 1 insertion(+), 1 deletion(-) |
| |
| --- a/drivers/net/ethernet/qlogic/qlge/qlge_dbg.c |
| +++ b/drivers/net/ethernet/qlogic/qlge/qlge_dbg.c |
| @@ -724,7 +724,7 @@ static void ql_build_coredump_seg_header |
| seg_hdr->cookie = MPI_COREDUMP_COOKIE; |
| seg_hdr->segNum = seg_number; |
| seg_hdr->segSize = seg_size; |
| - memcpy(seg_hdr->description, desc, (sizeof(seg_hdr->description)) - 1); |
| + strncpy(seg_hdr->description, desc, (sizeof(seg_hdr->description)) - 1); |
| } |
| |
| /* |
