Message ID | 20211130151731.55951-1-dust.li@linux.alibaba.com (mailing list archive) |
---|---|
State | Superseded |
Delegated to: | Netdev Maintainers |
Headers | show |
Series | [net] net/smc: fix wrong list_del in smc_lgr_cleanup_early | expand |
Context | Check | Description |
---|---|---|
netdev/tree_selection | success | Clearly marked for net |
netdev/fixes_present | success | Fixes tag present in non-next series |
netdev/subject_prefix | success | Link |
netdev/cover_letter | success | Single patches do not need cover letters |
netdev/patch_count | success | Link |
netdev/header_inline | success | No static functions without inline keyword in header files |
netdev/build_32bit | fail | Errors and warnings before: 0 this patch: 1 |
netdev/cc_maintainers | success | CCed 6 of 6 maintainers |
netdev/build_clang | fail | Errors and warnings before: 0 this patch: 2 |
netdev/module_param | success | Was 0 now: 0 |
netdev/verify_signedoff | success | Signed-off-by tag matches author and committer |
netdev/verify_fixes | success | Fixes tag looks correct |
netdev/build_allmodconfig_warn | fail | Errors and warnings before: 0 this patch: 1 |
netdev/checkpatch | success | total: 0 errors, 0 warnings, 0 checks, 10 lines checked |
netdev/kdoc | success | Errors and warnings before: 0 this patch: 0 |
netdev/source_inline | success | Was 0 now: 0 |
On 30/11/2021 16:17, Dust Li wrote: > smc_lgr_cleanup_early() meant to deleted the link > group from the link group list, but it deleted > the list head by mistake. > > This may cause memory corruption since we didn't > remove the real link group from the list and later > memseted the link group structure. Great finding, thank you! Acked-by: Karsten Graul <kgraul@linux.ibm.com>
Hi Dust,
Thank you for the patch! Perhaps something to improve:
[auto build test WARNING on net/master]
url: https://github.com/0day-ci/linux/commits/Dust-Li/net-smc-fix-wrong-list_del-in-smc_lgr_cleanup_early/20211130-232151
base: https://git.kernel.org/pub/scm/linux/kernel/git/davem/net.git 34d8778a943761121f391b7921f79a7adbe1feaf
config: arc-allyesconfig (https://download.01.org/0day-ci/archive/20211201/202112010159.e2LA9rIR-lkp@intel.com/config)
compiler: arceb-elf-gcc (GCC) 11.2.0
reproduce (this is a W=1 build):
wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
chmod +x ~/bin/make.cross
# https://github.com/0day-ci/linux/commit/9b9af6a458f20989d91478dc8e038325978e16d5
git remote add linux-review https://github.com/0day-ci/linux
git fetch --no-tags linux-review Dust-Li/net-smc-fix-wrong-list_del-in-smc_lgr_cleanup_early/20211130-232151
git checkout 9b9af6a458f20989d91478dc8e038325978e16d5
# save the config file to linux build tree
mkdir build_dir
COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-11.2.0 make.cross O=build_dir ARCH=arc SHELL=/bin/bash net/smc/
If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@intel.com>
All warnings (new ones prefixed by >>):
net/smc/smc_core.c: In function 'smc_lgr_cleanup_early':
>> net/smc/smc_core.c:628:27: warning: variable 'lgr_list' set but not used [-Wunused-but-set-variable]
628 | struct list_head *lgr_list;
| ^~~~~~~~
vim +/lgr_list +628 net/smc/smc_core.c
8f9dde4bf230f5 Guvenc Gulce 2020-12-01 624
51e3dfa8906ace Ursula Braun 2020-02-25 625 void smc_lgr_cleanup_early(struct smc_connection *conn)
51e3dfa8906ace Ursula Braun 2020-02-25 626 {
51e3dfa8906ace Ursula Braun 2020-02-25 627 struct smc_link_group *lgr = conn->lgr;
9ec6bf19ec8bb1 Karsten Graul 2020-05-03 @628 struct list_head *lgr_list;
9ec6bf19ec8bb1 Karsten Graul 2020-05-03 629 spinlock_t *lgr_lock;
51e3dfa8906ace Ursula Braun 2020-02-25 630
51e3dfa8906ace Ursula Braun 2020-02-25 631 if (!lgr)
51e3dfa8906ace Ursula Braun 2020-02-25 632 return;
51e3dfa8906ace Ursula Braun 2020-02-25 633
51e3dfa8906ace Ursula Braun 2020-02-25 634 smc_conn_free(conn);
9ec6bf19ec8bb1 Karsten Graul 2020-05-03 635 lgr_list = smc_lgr_list_head(lgr, &lgr_lock);
9ec6bf19ec8bb1 Karsten Graul 2020-05-03 636 spin_lock_bh(lgr_lock);
9ec6bf19ec8bb1 Karsten Graul 2020-05-03 637 /* do not use this link group for new connections */
9b9af6a458f209 Dust Li 2021-11-30 638 if (!list_empty(&lgr->list))
9b9af6a458f209 Dust Li 2021-11-30 639 list_del_init(&lgr->list);
9ec6bf19ec8bb1 Karsten Graul 2020-05-03 640 spin_unlock_bh(lgr_lock);
f9aab6f2ce5761 Ursula Braun 2020-09-10 641 __smc_lgr_terminate(lgr, true);
51e3dfa8906ace Ursula Braun 2020-02-25 642 }
51e3dfa8906ace Ursula Braun 2020-02-25 643
---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org
On Wed, Dec 01, 2021 at 02:07:46AM +0800, kernel test robot wrote: >Hi Dust, > >Thank you for the patch! Perhaps something to improve: > >[auto build test WARNING on net/master] > >url: https://github.com/0day-ci/linux/commits/Dust-Li/net-smc-fix-wrong-list_del-in-smc_lgr_cleanup_early/20211130-232151 >base: https://git.kernel.org/pub/scm/linux/kernel/git/davem/net.git 34d8778a943761121f391b7921f79a7adbe1feaf >config: arc-allyesconfig (https://download.01.org/0day-ci/archive/20211201/202112010159.e2LA9rIR-lkp@intel.com/config) >compiler: arceb-elf-gcc (GCC) 11.2.0 >reproduce (this is a W=1 build): > wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross > chmod +x ~/bin/make.cross > # https://github.com/0day-ci/linux/commit/9b9af6a458f20989d91478dc8e038325978e16d5 > git remote add linux-review https://github.com/0day-ci/linux > git fetch --no-tags linux-review Dust-Li/net-smc-fix-wrong-list_del-in-smc_lgr_cleanup_early/20211130-232151 > git checkout 9b9af6a458f20989d91478dc8e038325978e16d5 > # save the config file to linux build tree > mkdir build_dir > COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-11.2.0 make.cross O=build_dir ARCH=arc SHELL=/bin/bash net/smc/ > >If you fix the issue, kindly add following tag as appropriate >Reported-by: kernel test robot <lkp@intel.com> > >All warnings (new ones prefixed by >>): > > net/smc/smc_core.c: In function 'smc_lgr_cleanup_early': >>> net/smc/smc_core.c:628:27: warning: variable 'lgr_list' set but not used [-Wunused-but-set-variable] > 628 | struct list_head *lgr_list; > | ^~~~~~~~ Sorry, I will send a v2 to fix this. > > >vim +/lgr_list +628 net/smc/smc_core.c > >8f9dde4bf230f5 Guvenc Gulce 2020-12-01 624 >51e3dfa8906ace Ursula Braun 2020-02-25 625 void smc_lgr_cleanup_early(struct smc_connection *conn) >51e3dfa8906ace Ursula Braun 2020-02-25 626 { >51e3dfa8906ace Ursula Braun 2020-02-25 627 struct smc_link_group *lgr = conn->lgr; >9ec6bf19ec8bb1 Karsten Graul 2020-05-03 @628 struct list_head *lgr_list; >9ec6bf19ec8bb1 Karsten Graul 2020-05-03 629 spinlock_t *lgr_lock; >51e3dfa8906ace Ursula Braun 2020-02-25 630 >51e3dfa8906ace Ursula Braun 2020-02-25 631 if (!lgr) >51e3dfa8906ace Ursula Braun 2020-02-25 632 return; >51e3dfa8906ace Ursula Braun 2020-02-25 633 >51e3dfa8906ace Ursula Braun 2020-02-25 634 smc_conn_free(conn); >9ec6bf19ec8bb1 Karsten Graul 2020-05-03 635 lgr_list = smc_lgr_list_head(lgr, &lgr_lock); >9ec6bf19ec8bb1 Karsten Graul 2020-05-03 636 spin_lock_bh(lgr_lock); >9ec6bf19ec8bb1 Karsten Graul 2020-05-03 637 /* do not use this link group for new connections */ >9b9af6a458f209 Dust Li 2021-11-30 638 if (!list_empty(&lgr->list)) >9b9af6a458f209 Dust Li 2021-11-30 639 list_del_init(&lgr->list); >9ec6bf19ec8bb1 Karsten Graul 2020-05-03 640 spin_unlock_bh(lgr_lock); >f9aab6f2ce5761 Ursula Braun 2020-09-10 641 __smc_lgr_terminate(lgr, true); >51e3dfa8906ace Ursula Braun 2020-02-25 642 } >51e3dfa8906ace Ursula Braun 2020-02-25 643 > >--- >0-DAY CI Kernel Test Service, Intel Corporation >https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org
diff --git a/net/smc/smc_core.c b/net/smc/smc_core.c index bb52c8b5f148..ae2d5fa6dfca 100644 --- a/net/smc/smc_core.c +++ b/net/smc/smc_core.c @@ -635,8 +635,8 @@ void smc_lgr_cleanup_early(struct smc_connection *conn) lgr_list = smc_lgr_list_head(lgr, &lgr_lock); spin_lock_bh(lgr_lock); /* do not use this link group for new connections */ - if (!list_empty(lgr_list)) - list_del_init(lgr_list); + if (!list_empty(&lgr->list)) + list_del_init(&lgr->list); spin_unlock_bh(lgr_lock); __smc_lgr_terminate(lgr, true); }
smc_lgr_cleanup_early() meant to deleted the link group from the link group list, but it deleted the list head by mistake. This may cause memory corruption since we didn't remove the real link group from the list and later memseted the link group structure. We got a list corruption panic when testing: [ 231.277259] list_del corruption. prev->next should be ffff8881398a8000, but was 0000000000000000 [ 231.278222] ------------[ cut here ]------------ [ 231.278726] kernel BUG at lib/list_debug.c:53! [ 231.279326] invalid opcode: 0000 [#1] SMP NOPTI [ 231.279803] CPU: 0 PID: 5 Comm: kworker/0:0 Not tainted 5.10.46+ #435 [ 231.280466] Hardware name: Alibaba Cloud ECS, BIOS 8c24b4c 04/01/2014 [ 231.281248] Workqueue: events smc_link_down_work [ 231.281732] RIP: 0010:__list_del_entry_valid+0x70/0x90 [ 231.282258] Code: 4c 60 82 e8 7d cc 6a 00 0f 0b 48 89 fe 48 c7 c7 88 4c 60 82 e8 6c cc 6a 00 0f 0b 48 89 fe 48 c7 c7 c0 4c 60 82 e8 5b cc 6a 00 <0f> 0b 48 89 fe 48 c7 c7 00 4d 60 82 e8 4a cc 6a 00 0f 0b cc cc cc [ 231.284146] RSP: 0018:ffffc90000033d58 EFLAGS: 00010292 [ 231.284685] RAX: 0000000000000054 RBX: ffff8881398a8000 RCX: 0000000000000000 [ 231.285415] RDX: 0000000000000001 RSI: ffff88813bc18040 RDI: ffff88813bc18040 [ 231.286141] RBP: ffffffff8305ad40 R08: 0000000000000003 R09: 0000000000000001 [ 231.286873] R10: ffffffff82803da0 R11: ffffc90000033b90 R12: 0000000000000001 [ 231.287606] R13: 0000000000000000 R14: ffff8881398a8000 R15: 0000000000000003 [ 231.288337] FS: 0000000000000000(0000) GS:ffff88813bc00000(0000) knlGS:0000000000000000 [ 231.289160] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 231.289754] CR2: 0000000000e72058 CR3: 000000010fa96006 CR4: 00000000003706f0 [ 231.290485] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 231.291211] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 231.291940] Call Trace: [ 231.292211] smc_lgr_terminate_sched+0x53/0xa0 [ 231.292677] smc_switch_conns+0x75/0x6b0 [ 231.293085] ? update_load_avg+0x1a6/0x590 [ 231.293517] ? ttwu_do_wakeup+0x17/0x150 [ 231.293907] ? update_load_avg+0x1a6/0x590 [ 231.294317] ? newidle_balance+0xca/0x3d0 [ 231.294716] smcr_link_down+0x50/0x1a0 [ 231.295090] ? __wake_up_common_lock+0x77/0x90 [ 231.295534] smc_link_down_work+0x46/0x60 [ 231.295933] process_one_work+0x18b/0x350 Fixes: a0a62ee15a829 ("net/smc: separate locks for SMCD and SMCR link group lists") Signed-off-by: Dust Li <dust.li@linux.alibaba.com> --- net/smc/smc_core.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)