| Message ID | 20200731210255.3821452-1-ndesaulniers@google.com |
|---|---|
| State | Superseded |
| Headers | show |
| Series | [4.19] wireless: Use offsetof instead of custom macro. | expand |
On Fri, Jul 31, 2020 at 02:02:55PM -0700, Nick Desaulniers wrote: > From: Pi-Hsun Shih <pihsun@chromium.org> > > commit 6989310f5d4327e8595664954edd40a7f99ddd0d upstream. > > Use offsetof to calculate offset of a field to take advantage of > compiler built-in version when possible, and avoid UBSAN warning when > compiling with Clang: > > ================================================================== > UBSAN: Undefined behaviour in net/wireless/wext-core.c:525:14 > member access within null pointer of type 'struct iw_point' > CPU: 3 PID: 165 Comm: kworker/u16:3 Tainted: G S W 4.19.23 #43 > Workqueue: cfg80211 __cfg80211_scan_done [cfg80211] > Call trace: > dump_backtrace+0x0/0x194 > show_stack+0x20/0x2c > __dump_stack+0x20/0x28 > dump_stack+0x70/0x94 > ubsan_epilogue+0x14/0x44 > ubsan_type_mismatch_common+0xf4/0xfc > __ubsan_handle_type_mismatch_v1+0x34/0x54 > wireless_send_event+0x3cc/0x470 > ___cfg80211_scan_done+0x13c/0x220 [cfg80211] > __cfg80211_scan_done+0x28/0x34 [cfg80211] > process_one_work+0x170/0x35c > worker_thread+0x254/0x380 > kthread+0x13c/0x158 > ret_from_fork+0x10/0x18 > =================================================================== > > Signed-off-by: Pi-Hsun Shih <pihsun@chromium.org> > Reviewed-by: Nick Desaulniers <ndesaulniers@google.com> > Link: https://lore.kernel.org/r/20191204081307.138765-1-pihsun@chromium.org > Signed-off-by: Johannes Berg <johannes.berg@intel.com> > Signed-off-by: Nick Desaulniers <ndesaulniers@google.com> > --- > Fix landed in v5.7-rc1. Thanks to James Hsu of MediaTek for the report. What about 5.4.y? Why ignore that tree? You can not have people moving from an older stable to a newer stable tree and have regressions :( I'll queue it up there, but be more careful next time please. greg k-h
On Sat, Aug 1, 2020 at 5:02 AM Greg KH <greg@kroah.com> wrote: > > On Fri, Jul 31, 2020 at 02:02:55PM -0700, Nick Desaulniers wrote: > > Fix landed in v5.7-rc1. Thanks to James Hsu of MediaTek for the report. > > What about 5.4.y? Why ignore that tree? You can not have people moving > from an older stable to a newer stable tree and have regressions :( > > I'll queue it up there, but be more careful next time please. Yes, sorry, my mistake. I don't know what happened; perhaps I forgot how to count. -- Thanks, ~Nick Desaulniers
================================================================== UBSAN: Undefined behaviour in net/wireless/wext-core.c:525:14 member access within null pointer of type 'struct iw_point' CPU: 3 PID: 165 Comm: kworker/u16:3 Tainted: G S W 4.19.23 #43 Workqueue: cfg80211 __cfg80211_scan_done [cfg80211] Call trace: dump_backtrace+0x0/0x194 show_stack+0x20/0x2c __dump_stack+0x20/0x28 dump_stack+0x70/0x94 ubsan_epilogue+0x14/0x44 ubsan_type_mismatch_common+0xf4/0xfc __ubsan_handle_type_mismatch_v1+0x34/0x54 wireless_send_event+0x3cc/0x470 ___cfg80211_scan_done+0x13c/0x220 [cfg80211] __cfg80211_scan_done+0x28/0x34 [cfg80211] process_one_work+0x170/0x35c worker_thread+0x254/0x380 kthread+0x13c/0x158 ret_from_fork+0x10/0x18 =================================================================== Signed-off-by: Pi-Hsun Shih <pihsun@chromium.org> Reviewed-by: Nick Desaulniers <ndesaulniers@google.com> Link: https://lore.kernel.org/r/20191204081307.138765-1-pihsun@chromium.org Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: Nick Desaulniers <ndesaulniers@google.com> --- Fix landed in v5.7-rc1. Thanks to James Hsu of MediaTek for the report. include/uapi/linux/wireless.h | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/include/uapi/linux/wireless.h b/include/uapi/linux/wireless.h index 86eca3208b6b..a2c006a364e0 100644 --- a/include/uapi/linux/wireless.h +++ b/include/uapi/linux/wireless.h @@ -74,6 +74,8 @@ #include <linux/socket.h> /* for "struct sockaddr" et al */ #include <linux/if.h> /* for IFNAMSIZ and co... */ +#include <stddef.h> /* for offsetof */ + /***************************** VERSION *****************************/ /* * This constant is used to know the availability of the wireless @@ -1090,8 +1092,7 @@ struct iw_event { /* iw_point events are special. First, the payload (extra data) come at * the end of the event, so they are bigger than IW_EV_POINT_LEN. Second, * we omit the pointer, so start at an offset. */ -#define IW_EV_POINT_OFF (((char *) &(((struct iw_point *) NULL)->length)) - \ - (char *) NULL) +#define IW_EV_POINT_OFF offsetof(struct iw_point, length) #define IW_EV_POINT_LEN (IW_EV_LCP_LEN + sizeof(struct iw_point) - \ IW_EV_POINT_OFF)
From: Pi-Hsun Shih <pihsun@chromium.org> commit 6989310f5d4327e8595664954edd40a7f99ddd0d upstream. Use offsetof to calculate offset of a field to take advantage of compiler built-in version when possible, and avoid UBSAN warning when compiling with Clang: -- 2.28.0.163.g6104cc2f0b6-goog