| Message ID | 20220505233101.1224230-1-keescook@chromium.org (mailing list archive) |
|---|---|
| State | Accepted |
| Commit | 1c7ab9cd98b78bef1657a5db7204d8d437e24c94 |
| Delegated to: | Netdev Maintainers |
| Headers | show |
| Series | [v2] net: chelsio: cxgb4: Avoid potential negative array offset | expand |
Hello: This patch was applied to netdev/net.git (master) by Jakub Kicinski <kuba@kernel.org>: On Thu, 5 May 2022 16:31:01 -0700 you wrote: > Using min_t(int, ...) as a potential array index implies to the compiler > that negative offsets should be allowed. This is not the case, though. > Replace "int" with "unsigned int". Fixes the following warning exposed > under future CONFIG_FORTIFY_SOURCE improvements: > > In file included from include/linux/string.h:253, > from include/linux/bitmap.h:11, > from include/linux/cpumask.h:12, > from include/linux/smp.h:13, > from include/linux/lockdep.h:14, > from include/linux/rcupdate.h:29, > from include/linux/rculist.h:11, > from include/linux/pid.h:5, > from include/linux/sched.h:14, > from include/linux/delay.h:23, > from drivers/net/ethernet/chelsio/cxgb4/t4_hw.c:35: > drivers/net/ethernet/chelsio/cxgb4/t4_hw.c: In function 't4_get_raw_vpd_params': > include/linux/fortify-string.h:46:33: warning: '__builtin_memcpy' pointer overflow between offset 29 and size [2147483648, 4294967295] [-Warray-bounds] > 46 | #define __underlying_memcpy __builtin_memcpy > | ^ > include/linux/fortify-string.h:388:9: note: in expansion of macro '__underlying_memcpy' > 388 | __underlying_##op(p, q, __fortify_size); \ > | ^~~~~~~~~~~~~ > include/linux/fortify-string.h:433:26: note: in expansion of macro '__fortify_memcpy_chk' > 433 | #define memcpy(p, q, s) __fortify_memcpy_chk(p, q, s, \ > | ^~~~~~~~~~~~~~~~~~~~ > drivers/net/ethernet/chelsio/cxgb4/t4_hw.c:2796:9: note: in expansion of macro 'memcpy' > 2796 | memcpy(p->id, vpd + id, min_t(int, id_len, ID_LEN)); > | ^~~~~~ > include/linux/fortify-string.h:46:33: warning: '__builtin_memcpy' pointer overflow between offset 0 and size [2147483648, 4294967295] [-Warray-bounds] > 46 | #define __underlying_memcpy __builtin_memcpy > | ^ > include/linux/fortify-string.h:388:9: note: in expansion of macro '__underlying_memcpy' > 388 | __underlying_##op(p, q, __fortify_size); \ > | ^~~~~~~~~~~~~ > include/linux/fortify-string.h:433:26: note: in expansion of macro '__fortify_memcpy_chk' > 433 | #define memcpy(p, q, s) __fortify_memcpy_chk(p, q, s, \ > | ^~~~~~~~~~~~~~~~~~~~ > drivers/net/ethernet/chelsio/cxgb4/t4_hw.c:2798:9: note: in expansion of macro 'memcpy' > 2798 | memcpy(p->sn, vpd + sn, min_t(int, sn_len, SERNUM_LEN)); > | ^~~~~~ > > [...] Here is the summary with links: - [v2] net: chelsio: cxgb4: Avoid potential negative array offset https://git.kernel.org/netdev/net/c/1c7ab9cd98b7 You are awesome, thank you!
diff --git a/drivers/net/ethernet/chelsio/cxgb4/t4_hw.c b/drivers/net/ethernet/chelsio/cxgb4/t4_hw.c index e7b4e3ed056c..8d719f82854a 100644 --- a/drivers/net/ethernet/chelsio/cxgb4/t4_hw.c +++ b/drivers/net/ethernet/chelsio/cxgb4/t4_hw.c @@ -2793,14 +2793,14 @@ int t4_get_raw_vpd_params(struct adapter *adapter, struct vpd_params *p) goto out; na = ret; - memcpy(p->id, vpd + id, min_t(int, id_len, ID_LEN)); + memcpy(p->id, vpd + id, min_t(unsigned int, id_len, ID_LEN)); strim(p->id); - memcpy(p->sn, vpd + sn, min_t(int, sn_len, SERNUM_LEN)); + memcpy(p->sn, vpd + sn, min_t(unsigned int, sn_len, SERNUM_LEN)); strim(p->sn); - memcpy(p->pn, vpd + pn, min_t(int, pn_len, PN_LEN)); + memcpy(p->pn, vpd + pn, min_t(unsigned int, pn_len, PN_LEN)); strim(p->pn); - memcpy(p->na, vpd + na, min_t(int, na_len, MACADDR_LEN)); - strim((char *)p->na); + memcpy(p->na, vpd + na, min_t(unsigned int, na_len, MACADDR_LEN)); + strim(p->na); out: vfree(vpd);
Using min_t(int, ...) as a potential array index implies to the compiler that negative offsets should be allowed. This is not the case, though. Replace "int" with "unsigned int". Fixes the following warning exposed under future CONFIG_FORTIFY_SOURCE improvements: In file included from include/linux/string.h:253, from include/linux/bitmap.h:11, from include/linux/cpumask.h:12, from include/linux/smp.h:13, from include/linux/lockdep.h:14, from include/linux/rcupdate.h:29, from include/linux/rculist.h:11, from include/linux/pid.h:5, from include/linux/sched.h:14, from include/linux/delay.h:23, from drivers/net/ethernet/chelsio/cxgb4/t4_hw.c:35: drivers/net/ethernet/chelsio/cxgb4/t4_hw.c: In function 't4_get_raw_vpd_params': include/linux/fortify-string.h:46:33: warning: '__builtin_memcpy' pointer overflow between offset 29 and size [2147483648, 4294967295] [-Warray-bounds] 46 | #define __underlying_memcpy __builtin_memcpy | ^ include/linux/fortify-string.h:388:9: note: in expansion of macro '__underlying_memcpy' 388 | __underlying_##op(p, q, __fortify_size); \ | ^~~~~~~~~~~~~ include/linux/fortify-string.h:433:26: note: in expansion of macro '__fortify_memcpy_chk' 433 | #define memcpy(p, q, s) __fortify_memcpy_chk(p, q, s, \ | ^~~~~~~~~~~~~~~~~~~~ drivers/net/ethernet/chelsio/cxgb4/t4_hw.c:2796:9: note: in expansion of macro 'memcpy' 2796 | memcpy(p->id, vpd + id, min_t(int, id_len, ID_LEN)); | ^~~~~~ include/linux/fortify-string.h:46:33: warning: '__builtin_memcpy' pointer overflow between offset 0 and size [2147483648, 4294967295] [-Warray-bounds] 46 | #define __underlying_memcpy __builtin_memcpy | ^ include/linux/fortify-string.h:388:9: note: in expansion of macro '__underlying_memcpy' 388 | __underlying_##op(p, q, __fortify_size); \ | ^~~~~~~~~~~~~ include/linux/fortify-string.h:433:26: note: in expansion of macro '__fortify_memcpy_chk' 433 | #define memcpy(p, q, s) __fortify_memcpy_chk(p, q, s, \ | ^~~~~~~~~~~~~~~~~~~~ drivers/net/ethernet/chelsio/cxgb4/t4_hw.c:2798:9: note: in expansion of macro 'memcpy' 2798 | memcpy(p->sn, vpd + sn, min_t(int, sn_len, SERNUM_LEN)); | ^~~~~~ Additionally remove needless cast from u8[] to char * in last strim() call. Reported-by: kernel test robot <lkp@intel.com> Link: https://lore.kernel.org/lkml/202205031926.FVP7epJM-lkp@intel.com Fixes: fc9279298e3a ("cxgb4: Search VPD with pci_vpd_find_ro_info_keyword()") Fixes: 24c521f81c30 ("cxgb4: Use pci_vpd_find_id_string() to find VPD ID string") Cc: Raju Rangoju <rajur@chelsio.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: Eric Dumazet <edumazet@google.com> Cc: Jakub Kicinski <kuba@kernel.org> Cc: Paolo Abeni <pabeni@redhat.com> Cc: netdev@vger.kernel.org Cc: stable@vger.kernel.org Signed-off-by: Kees Cook <keescook@chromium.org> --- v1: https://lore.kernel.org/lkml/20220503144425.2858110-1-keescook@chromium.org/ v2: use min_t again. --- drivers/net/ethernet/chelsio/cxgb4/t4_hw.c | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-)