* [BUG] staging: r8188eu: KASAN: slab-out-of-bounds in rtw_cmd_thread @ 2022-04-24 10:00 Michael Straube 2022-04-24 12:11 ` Solomon Tan 0 siblings, 1 reply; 6+ messages in thread From: Michael Straube @ 2022-04-24 10:00 UTC (permalink / raw) To: Greg KH Cc: Larry Finger, Phillip Potter, Solomon Tan, open list:STAGING SUBSYSTEM, Linux Kernel Mailing List, Michael Straube Hi, It looks like commit 0afaa121813e ("staging: r8188eu: use in-kernel ieee channel") intoduced a. See KASAN output below. That commit replaced the use of struct rtw_ieee80211_channel with struct ieee80211_channel. There are several calls to memcpy that used sizeof(struct rtw_ieee80211_channel) and now use sizeof(struct ieee80211_channel) but the sizes of these two structures are not equal. regards, Michael dmesg: ================================================================== [ 422.214237] BUG: KASAN: slab-out-of-bounds in rtw_cmd_thread+0x1e8/0x430 [r8188eu] [ 422.214277] Write of size 3600 at addr ffff8881e149d200 by task RTW_CMD_THREAD/2563 [ 422.214289] CPU: 11 PID: 2563 Comm: RTW_CMD_THREAD Tainted: G C OE 5.18.0-rc2-staging+ #47 94e3ca73bebf5b7fec506721475e4fff2a023bb9 [ 422.214301] Hardware name: Gigabyte Technology Co., Ltd. B550M S2H/B550M S2H, BIOS F15a 02/16/2022 [ 422.214309] Call Trace: [ 422.214313] <TASK> [ 422.214317] dump_stack_lvl+0x45/0x5b [ 422.214327] print_report.cold+0x5e/0x5dc [ 422.214335] ? kasan_set_track+0x21/0x30 [ 422.214342] ? kasan_set_free_info+0x20/0x40 [ 422.214349] ? rtw_cmd_thread+0x1e8/0x430 [r8188eu 91924fe1575bf49b9b37985ffde2c585d847446d] [ 422.214386] kasan_report+0xab/0x120 [ 422.214394] ? rtw_cmd_thread+0x1e8/0x430 [r8188eu 91924fe1575bf49b9b37985ffde2c585d847446d] [ 422.214430] kasan_check_range+0xf6/0x1d0 [ 422.214436] memcpy+0x39/0x60 [ 422.214442] rtw_cmd_thread+0x1e8/0x430 [r8188eu 91924fe1575bf49b9b37985ffde2c585d847446d] [ 422.214479] ? rtw_setassocsta_cmdrsp_callback+0xd0/0xd0 [r8188eu 91924fe1575bf49b9b37985ffde2c585d847446d] [ 422.214516] kthread+0x15d/0x190 [ 422.214523] ? kthread_complete_and_exit+0x20/0x20 [ 422.214531] ret_from_fork+0x22/0x30 [ 422.214540] </TASK> [ 422.214546] Allocated by task 2522: [ 422.214551] kasan_save_stack+0x1e/0x40 [ 422.214555] __kasan_kmalloc+0xa9/0xe0 [ 422.214559] rtw_init_cmd_priv+0xd6/0x1b0 [r8188eu] [ 422.214589] rtw_init_drv_sw+0x21/0x370 [r8188eu] [ 422.214619] rtw_drv_init+0x3a6/0x4f0 [r8188eu] [ 422.214649] usb_probe_interface+0x155/0x340 [usbcore] [ 422.214705] really_probe.part.0+0x11f/0x320 [ 422.214709] __driver_probe_device+0xe0/0x180 [ 422.214712] driver_probe_device+0x4d/0x170 [ 422.214715] __driver_attach+0x110/0x250 [ 422.214718] bus_for_each_dev+0xe7/0x140 [ 422.214721] bus_add_driver+0x25a/0x2b0 [ 422.214723] driver_register+0x10f/0x190 [ 422.214726] usb_register_driver+0x10e/0x1e0 [usbcore] [ 422.214780] do_one_initcall+0x8a/0x2a0 [ 422.214784] do_init_module+0xe4/0x3b0 [ 422.214787] load_module+0x41c4/0x4650 [ 422.214789] __do_sys_finit_module+0x111/0x190 [ 422.214791] do_syscall_64+0x5c/0x80 [ 422.214795] entry_SYSCALL_64_after_hwframe+0x44/0xae [ 422.214802] Last potentially related work creation: [ 422.214807] kasan_save_stack+0x1e/0x40 [ 422.214810] __kasan_record_aux_stack+0xb1/0xc0 [ 422.214813] call_rcu+0xb5/0xfc0 [ 422.214817] netlink_release+0x791/0xa40 [ 422.214820] __sock_release+0x72/0x120 [ 422.214824] sock_close+0x11/0x20 [ 422.214828] __fput+0x10c/0x400 [ 422.214831] task_work_run+0x8b/0xc0 [ 422.214834] do_exit+0x5a4/0x10e0 [ 422.214837] do_group_exit+0x58/0x100 [ 422.214840] __x64_sys_exit_group+0x28/0x30 [ 422.214843] do_syscall_64+0x5c/0x80 [ 422.214846] entry_SYSCALL_64_after_hwframe+0x44/0xae [ 422.214852] The buggy address belongs to the object at ffff8881e149d000 which belongs to the cache kmalloc-2k of size 2048 [ 422.214862] The buggy address is located 512 bytes inside of 2048-byte region [ffff8881e149d000, ffff8881e149d800) [ 422.214874] The buggy address belongs to the physical page: [ 422.214879] page:000000003f187866 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x1e1498 [ 422.214883] head:000000003f187866 order:3 compound_mapcount:0 compound_pincount:0 [ 422.214885] flags: 0x17ffffc0010200(slab|head|node=0|zone=2|lastcpupid=0x1fffff) [ 422.214891] raw: 0017ffffc0010200 ffffea0004f1ca00 dead000000000002 ffff888100042f00 [ 422.214894] raw: 0000000000000000 0000000000080008 00000001ffffffff 0000000000000000 [ 422.214896] page dumped because: kasan: bad access detected [ 422.214900] Memory state around the buggy address: [ 422.214905] ffff8881e149d500: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 422.214914] ffff8881e149d580: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 422.214921] >ffff8881e149d600: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 422.214927] ^ [ 422.214932] ffff8881e149d680: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 422.214939] ffff8881e149d700: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 422.214946] ================================================================== ^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [BUG] staging: r8188eu: KASAN: slab-out-of-bounds in rtw_cmd_thread 2022-04-24 10:00 [BUG] staging: r8188eu: KASAN: slab-out-of-bounds in rtw_cmd_thread Michael Straube @ 2022-04-24 12:11 ` Solomon Tan 2022-04-24 15:06 ` Pavel Skripkin 0 siblings, 1 reply; 6+ messages in thread From: Solomon Tan @ 2022-04-24 12:11 UTC (permalink / raw) To: Michael Straube Cc: Greg KH, Larry Finger, Phillip Potter, open list:STAGING SUBSYSTEM, Linux Kernel Mailing List On Sun, Apr 24, 2022 at 12:00:12PM +0200, Michael Straube wrote: > Hi, > > It looks like > commit 0afaa121813e ("staging: r8188eu: use in-kernel ieee channel") > intoduced a. See KASAN output below. > > That commit replaced the use of struct rtw_ieee80211_channel with struct > ieee80211_channel. > > There are several calls to memcpy that used sizeof(struct > rtw_ieee80211_channel) > and now use sizeof(struct ieee80211_channel) but the sizes of these two > structures are not equal. > Oh no. When does this issue get triggered? > regards, > Michael > > dmesg: > > ================================================================== > [ 422.214237] BUG: KASAN: slab-out-of-bounds in rtw_cmd_thread+0x1e8/0x430 > [r8188eu] > [ 422.214277] Write of size 3600 at addr ffff8881e149d200 by task > RTW_CMD_THREAD/2563 > > [ 422.214289] CPU: 11 PID: 2563 Comm: RTW_CMD_THREAD Tainted: G C OE > 5.18.0-rc2-staging+ #47 94e3ca73bebf5b7fec506721475e4fff2a023bb9 > [ 422.214301] Hardware name: Gigabyte Technology Co., Ltd. B550M S2H/B550M > S2H, BIOS F15a 02/16/2022 > [ 422.214309] Call Trace: > [ 422.214313] <TASK> > [ 422.214317] dump_stack_lvl+0x45/0x5b > [ 422.214327] print_report.cold+0x5e/0x5dc > [ 422.214335] ? kasan_set_track+0x21/0x30 > [ 422.214342] ? kasan_set_free_info+0x20/0x40 > [ 422.214349] ? rtw_cmd_thread+0x1e8/0x430 [r8188eu > 91924fe1575bf49b9b37985ffde2c585d847446d] > [ 422.214386] kasan_report+0xab/0x120 > [ 422.214394] ? rtw_cmd_thread+0x1e8/0x430 [r8188eu > 91924fe1575bf49b9b37985ffde2c585d847446d] > [ 422.214430] kasan_check_range+0xf6/0x1d0 > [ 422.214436] memcpy+0x39/0x60 > [ 422.214442] rtw_cmd_thread+0x1e8/0x430 [r8188eu > 91924fe1575bf49b9b37985ffde2c585d847446d] > [ 422.214479] ? rtw_setassocsta_cmdrsp_callback+0xd0/0xd0 [r8188eu > 91924fe1575bf49b9b37985ffde2c585d847446d] > [ 422.214516] kthread+0x15d/0x190 > [ 422.214523] ? kthread_complete_and_exit+0x20/0x20 > [ 422.214531] ret_from_fork+0x22/0x30 > [ 422.214540] </TASK> Sorry, I am not familiar with KASAN. How should I interpret this output? I see the paragraph above has references to rtw_cmd_thread. I assume that is its way of indicating that rtw_cmd_thread is the cause of the problem, but the one below refers to other functions. I'm not sure where I should start looking. I would start looking at `rtw_sitesurvey_cmd` and `rtw_scan_ch_decision`, which call the memcpy on the rtw_ieee80211_channel structure, but they are not on the call trace. > > [ 422.214546] Allocated by task 2522: > [ 422.214551] kasan_save_stack+0x1e/0x40 > [ 422.214555] __kasan_kmalloc+0xa9/0xe0 > [ 422.214559] rtw_init_cmd_priv+0xd6/0x1b0 [r8188eu] > [ 422.214589] rtw_init_drv_sw+0x21/0x370 [r8188eu] > [ 422.214619] rtw_drv_init+0x3a6/0x4f0 [r8188eu] > [ 422.214649] usb_probe_interface+0x155/0x340 [usbcore] > [ 422.214705] really_probe.part.0+0x11f/0x320 > [ 422.214709] __driver_probe_device+0xe0/0x180 > [ 422.214712] driver_probe_device+0x4d/0x170 > [ 422.214715] __driver_attach+0x110/0x250 > [ 422.214718] bus_for_each_dev+0xe7/0x140 > [ 422.214721] bus_add_driver+0x25a/0x2b0 > [ 422.214723] driver_register+0x10f/0x190 > [ 422.214726] usb_register_driver+0x10e/0x1e0 [usbcore] > [ 422.214780] do_one_initcall+0x8a/0x2a0 > [ 422.214784] do_init_module+0xe4/0x3b0 > [ 422.214787] load_module+0x41c4/0x4650 > [ 422.214789] __do_sys_finit_module+0x111/0x190 > [ 422.214791] do_syscall_64+0x5c/0x80 > [ 422.214795] entry_SYSCALL_64_after_hwframe+0x44/0xae > > [ 422.214802] Last potentially related work creation: > [ 422.214807] kasan_save_stack+0x1e/0x40 > [ 422.214810] __kasan_record_aux_stack+0xb1/0xc0 > [ 422.214813] call_rcu+0xb5/0xfc0 > [ 422.214817] netlink_release+0x791/0xa40 > [ 422.214820] __sock_release+0x72/0x120 > [ 422.214824] sock_close+0x11/0x20 > [ 422.214828] __fput+0x10c/0x400 > [ 422.214831] task_work_run+0x8b/0xc0 > [ 422.214834] do_exit+0x5a4/0x10e0 > [ 422.214837] do_group_exit+0x58/0x100 > [ 422.214840] __x64_sys_exit_group+0x28/0x30 > [ 422.214843] do_syscall_64+0x5c/0x80 > [ 422.214846] entry_SYSCALL_64_after_hwframe+0x44/0xae > > [ 422.214852] The buggy address belongs to the object at ffff8881e149d000 > which belongs to the cache kmalloc-2k of size 2048 > [ 422.214862] The buggy address is located 512 bytes inside of > 2048-byte region [ffff8881e149d000, ffff8881e149d800) > > [ 422.214874] The buggy address belongs to the physical page: > [ 422.214879] page:000000003f187866 refcount:1 mapcount:0 > mapping:0000000000000000 index:0x0 pfn:0x1e1498 > [ 422.214883] head:000000003f187866 order:3 compound_mapcount:0 > compound_pincount:0 > [ 422.214885] flags: > 0x17ffffc0010200(slab|head|node=0|zone=2|lastcpupid=0x1fffff) > [ 422.214891] raw: 0017ffffc0010200 ffffea0004f1ca00 dead000000000002 > ffff888100042f00 > [ 422.214894] raw: 0000000000000000 0000000000080008 00000001ffffffff > 0000000000000000 > [ 422.214896] page dumped because: kasan: bad access detected > > [ 422.214900] Memory state around the buggy address: > [ 422.214905] ffff8881e149d500: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 > 00 00 > [ 422.214914] ffff8881e149d580: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 > 00 00 > [ 422.214921] >ffff8881e149d600: fc fc fc fc fc fc fc fc fc fc fc fc fc fc > fc fc > [ 422.214927] ^ > [ 422.214932] ffff8881e149d680: fc fc fc fc fc fc fc fc fc fc fc fc fc fc > fc fc > [ 422.214939] ffff8881e149d700: fc fc fc fc fc fc fc fc fc fc fc fc fc fc > fc fc > [ 422.214946] > ================================================================== ^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [BUG] staging: r8188eu: KASAN: slab-out-of-bounds in rtw_cmd_thread 2022-04-24 12:11 ` Solomon Tan @ 2022-04-24 15:06 ` Pavel Skripkin 2022-04-25 0:37 ` Solomon Tan 2022-04-25 15:41 ` Dan Carpenter 0 siblings, 2 replies; 6+ messages in thread From: Pavel Skripkin @ 2022-04-24 15:06 UTC (permalink / raw) To: Solomon Tan, Michael Straube Cc: Greg KH, Larry Finger, Phillip Potter, open list:STAGING SUBSYSTEM, Linux Kernel Mailing List Hi Solomon, On 4/24/22 15:11, Solomon Tan wrote: > On Sun, Apr 24, 2022 at 12:00:12PM +0200, Michael Straube wrote: >> Hi, >> >> It looks like >> commit 0afaa121813e ("staging: r8188eu: use in-kernel ieee channel") >> intoduced a. See KASAN output below. >> >> That commit replaced the use of struct rtw_ieee80211_channel with struct >> ieee80211_channel. >> >> There are several calls to memcpy that used sizeof(struct >> rtw_ieee80211_channel) >> and now use sizeof(struct ieee80211_channel) but the sizes of these two >> structures are not equal. >> > > Oh no. When does this issue get triggered? > >> regards, >> Michael >> >> dmesg: >> >> ================================================================== >> [ 422.214237] BUG: KASAN: slab-out-of-bounds in rtw_cmd_thread+0x1e8/0x430 >> [r8188eu] >> [ 422.214277] Write of size 3600 at addr ffff8881e149d200 by task >> RTW_CMD_THREAD/2563 >> >> [ 422.214289] CPU: 11 PID: 2563 Comm: RTW_CMD_THREAD Tainted: G C OE >> 5.18.0-rc2-staging+ #47 94e3ca73bebf5b7fec506721475e4fff2a023bb9 >> [ 422.214301] Hardware name: Gigabyte Technology Co., Ltd. B550M S2H/B550M >> S2H, BIOS F15a 02/16/2022 >> [ 422.214309] Call Trace: >> [ 422.214313] <TASK> >> [ 422.214317] dump_stack_lvl+0x45/0x5b >> [ 422.214327] print_report.cold+0x5e/0x5dc >> [ 422.214335] ? kasan_set_track+0x21/0x30 >> [ 422.214342] ? kasan_set_free_info+0x20/0x40 >> [ 422.214349] ? rtw_cmd_thread+0x1e8/0x430 [r8188eu >> 91924fe1575bf49b9b37985ffde2c585d847446d] >> [ 422.214386] kasan_report+0xab/0x120 >> [ 422.214394] ? rtw_cmd_thread+0x1e8/0x430 [r8188eu >> 91924fe1575bf49b9b37985ffde2c585d847446d] >> [ 422.214430] kasan_check_range+0xf6/0x1d0 >> [ 422.214436] memcpy+0x39/0x60 >> [ 422.214442] rtw_cmd_thread+0x1e8/0x430 [r8188eu >> 91924fe1575bf49b9b37985ffde2c585d847446d] >> [ 422.214479] ? rtw_setassocsta_cmdrsp_callback+0xd0/0xd0 [r8188eu >> 91924fe1575bf49b9b37985ffde2c585d847446d] >> [ 422.214516] kthread+0x15d/0x190 >> [ 422.214523] ? kthread_complete_and_exit+0x20/0x20 >> [ 422.214531] ret_from_fork+0x22/0x30 >> [ 422.214540] </TASK> > > Sorry, I am not familiar with KASAN. How should I interpret this output? > I see the paragraph above has references to rtw_cmd_thread. I assume > that is its way of indicating that rtw_cmd_thread is the cause of the > problem, but the one below refers to other functions. I'm not sure where > I should start looking. I would start looking at `rtw_sitesurvey_cmd` and > `rtw_scan_ch_decision`, which call the memcpy on the > rtw_ieee80211_channel structure, but they are not on the call trace. > drivers/staging/r8188eu/core/rtw_cmd.c:276: memcpy() call. As Michael said the sizes of structures do not mach and the memcpy writes below allocated buffer. With regards, Pavel Skripkin ^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [BUG] staging: r8188eu: KASAN: slab-out-of-bounds in rtw_cmd_thread 2022-04-24 15:06 ` Pavel Skripkin @ 2022-04-25 0:37 ` Solomon Tan 2022-04-25 15:41 ` Dan Carpenter 1 sibling, 0 replies; 6+ messages in thread From: Solomon Tan @ 2022-04-25 0:37 UTC (permalink / raw) To: straube.linux, paskripkin Cc: Greg KH, Larry Finger, Phillip Potter, open list:STAGING SUBSYSTEM, Linux Kernel Mailing List > > > It looks like > > > commit 0afaa121813e ("staging: r8188eu: use in-kernel ieee channel") > > > intoduced a. See KASAN output below. > > > > > > That commit replaced the use of struct rtw_ieee80211_channel with struct > > > ieee80211_channel. > > > > > > There are several calls to memcpy that used sizeof(struct > > > rtw_ieee80211_channel) > > > and now use sizeof(struct ieee80211_channel) but the sizes of these two > > > structures are not equal. > > > > > drivers/staging/r8188eu/core/rtw_cmd.c:276: memcpy() call. > > As Michael said the sizes of structures do not mach and the memcpy writes > below allocated buffer. > Thanks Pavel. Hi Michael, I could not find the cause of this issue, and I am afraid I might break even more stuff if I attempt to fix it, so I have submitted a new patch to revert my changes. Sorry for the inconvenience. Cheers, Solomon ^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [BUG] staging: r8188eu: KASAN: slab-out-of-bounds in rtw_cmd_thread 2022-04-24 15:06 ` Pavel Skripkin 2022-04-25 0:37 ` Solomon Tan @ 2022-04-25 15:41 ` Dan Carpenter 2022-04-26 2:48 ` Solomon Tan 1 sibling, 1 reply; 6+ messages in thread From: Dan Carpenter @ 2022-04-25 15:41 UTC (permalink / raw) To: Pavel Skripkin Cc: Solomon Tan, Michael Straube, Greg KH, Larry Finger, Phillip Potter, open list:STAGING SUBSYSTEM, Linux Kernel Mailing List On Sun, Apr 24, 2022 at 06:06:32PM +0300, Pavel Skripkin wrote: > Hi Solomon, > > On 4/24/22 15:11, Solomon Tan wrote: > > On Sun, Apr 24, 2022 at 12:00:12PM +0200, Michael Straube wrote: > > > Hi, > > > > > > It looks like > > > commit 0afaa121813e ("staging: r8188eu: use in-kernel ieee channel") > > > intoduced a. See KASAN output below. > > > > > > That commit replaced the use of struct rtw_ieee80211_channel with struct > > > ieee80211_channel. > > > > > > There are several calls to memcpy that used sizeof(struct > > > rtw_ieee80211_channel) > > > and now use sizeof(struct ieee80211_channel) but the sizes of these two > > > structures are not equal. > > > > > > > Oh no. When does this issue get triggered? > > > > > regards, > > > Michael > > > > > > dmesg: > > > > > > ================================================================== > > > [ 422.214237] BUG: KASAN: slab-out-of-bounds in rtw_cmd_thread+0x1e8/0x430 > > > [r8188eu] > > > [ 422.214277] Write of size 3600 at addr ffff8881e149d200 by task > > > RTW_CMD_THREAD/2563 > > > > > > [ 422.214289] CPU: 11 PID: 2563 Comm: RTW_CMD_THREAD Tainted: G C OE > > > 5.18.0-rc2-staging+ #47 94e3ca73bebf5b7fec506721475e4fff2a023bb9 > > > [ 422.214301] Hardware name: Gigabyte Technology Co., Ltd. B550M S2H/B550M > > > S2H, BIOS F15a 02/16/2022 > > > [ 422.214309] Call Trace: > > > [ 422.214313] <TASK> > > > [ 422.214317] dump_stack_lvl+0x45/0x5b > > > [ 422.214327] print_report.cold+0x5e/0x5dc > > > [ 422.214335] ? kasan_set_track+0x21/0x30 > > > [ 422.214342] ? kasan_set_free_info+0x20/0x40 > > > [ 422.214349] ? rtw_cmd_thread+0x1e8/0x430 [r8188eu > > > 91924fe1575bf49b9b37985ffde2c585d847446d] > > > [ 422.214386] kasan_report+0xab/0x120 > > > [ 422.214394] ? rtw_cmd_thread+0x1e8/0x430 [r8188eu > > > 91924fe1575bf49b9b37985ffde2c585d847446d] > > > [ 422.214430] kasan_check_range+0xf6/0x1d0 > > > [ 422.214436] memcpy+0x39/0x60 > > > [ 422.214442] rtw_cmd_thread+0x1e8/0x430 [r8188eu > > > 91924fe1575bf49b9b37985ffde2c585d847446d] > > > [ 422.214479] ? rtw_setassocsta_cmdrsp_callback+0xd0/0xd0 [r8188eu > > > 91924fe1575bf49b9b37985ffde2c585d847446d] > > > [ 422.214516] kthread+0x15d/0x190 > > > [ 422.214523] ? kthread_complete_and_exit+0x20/0x20 > > > [ 422.214531] ret_from_fork+0x22/0x30 > > > [ 422.214540] </TASK> > > > > Sorry, I am not familiar with KASAN. How should I interpret this output? > > I see the paragraph above has references to rtw_cmd_thread. I assume > > that is its way of indicating that rtw_cmd_thread is the cause of the > > problem, but the one below refers to other functions. I'm not sure where > > I should start looking. I would start looking at `rtw_sitesurvey_cmd` and > > `rtw_scan_ch_decision`, which call the memcpy on the > > rtw_ieee80211_channel structure, but they are not on the call trace. > > > > drivers/staging/r8188eu/core/rtw_cmd.c:276: memcpy() call. > What git hash are you on? Is that the line: memcpy(&psurveyPara->ch[i], &ch[i], sizeof(struct ieee80211_channel)); Are you sure that's the line which crashes? According to Smatch and my simple grep that's dead code because "ch" is always NULL. > As Michael said the sizes of structures do not mach and the memcpy writes > below allocated buffer. I feel a bit bad for not spotting this in review because I was looking for that kind of bug. I still don't immediately spot where the bug is. regards, dan carpenter ^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [BUG] staging: r8188eu: KASAN: slab-out-of-bounds in rtw_cmd_thread 2022-04-25 15:41 ` Dan Carpenter @ 2022-04-26 2:48 ` Solomon Tan 0 siblings, 0 replies; 6+ messages in thread From: Solomon Tan @ 2022-04-26 2:48 UTC (permalink / raw) To: Dan Carpenter Cc: Pavel Skripkin, Michael Straube, Greg KH, Larry Finger, Phillip Potter, open list:STAGING SUBSYSTEM, Linux Kernel Mailing List On Mon, Apr 25, 2022 at 06:41:38PM +0300, Dan Carpenter wrote: > On Sun, Apr 24, 2022 at 06:06:32PM +0300, Pavel Skripkin wrote: > > Hi Solomon, > > > > On 4/24/22 15:11, Solomon Tan wrote: > > > On Sun, Apr 24, 2022 at 12:00:12PM +0200, Michael Straube wrote: > > > > Hi, > > > > > > > > It looks like > > > > commit 0afaa121813e ("staging: r8188eu: use in-kernel ieee channel") > > > > intoduced a. See KASAN output below. > > > > > > > > That commit replaced the use of struct rtw_ieee80211_channel with struct > > > > ieee80211_channel. > > > > > > > > There are several calls to memcpy that used sizeof(struct > > > > rtw_ieee80211_channel) > > > > and now use sizeof(struct ieee80211_channel) but the sizes of these two > > > > structures are not equal. > > > > > > > > > > Oh no. When does this issue get triggered? > > > > > > > regards, > > > > Michael > > > > > > > > dmesg: > > > > > > > > ================================================================== > > > > [ 422.214237] BUG: KASAN: slab-out-of-bounds in rtw_cmd_thread+0x1e8/0x430 > > > > [r8188eu] > > > > [ 422.214277] Write of size 3600 at addr ffff8881e149d200 by task > > > > RTW_CMD_THREAD/2563 > > > > > > > > [ 422.214289] CPU: 11 PID: 2563 Comm: RTW_CMD_THREAD Tainted: G C OE > > > > 5.18.0-rc2-staging+ #47 94e3ca73bebf5b7fec506721475e4fff2a023bb9 > > > > [ 422.214301] Hardware name: Gigabyte Technology Co., Ltd. B550M S2H/B550M > > > > S2H, BIOS F15a 02/16/2022 > > > > [ 422.214309] Call Trace: > > > > [ 422.214313] <TASK> > > > > [ 422.214317] dump_stack_lvl+0x45/0x5b > > > > [ 422.214327] print_report.cold+0x5e/0x5dc > > > > [ 422.214335] ? kasan_set_track+0x21/0x30 > > > > [ 422.214342] ? kasan_set_free_info+0x20/0x40 > > > > [ 422.214349] ? rtw_cmd_thread+0x1e8/0x430 [r8188eu > > > > 91924fe1575bf49b9b37985ffde2c585d847446d] > > > > [ 422.214386] kasan_report+0xab/0x120 > > > > [ 422.214394] ? rtw_cmd_thread+0x1e8/0x430 [r8188eu > > > > 91924fe1575bf49b9b37985ffde2c585d847446d] > > > > [ 422.214430] kasan_check_range+0xf6/0x1d0 > > > > [ 422.214436] memcpy+0x39/0x60 > > > > [ 422.214442] rtw_cmd_thread+0x1e8/0x430 [r8188eu > > > > 91924fe1575bf49b9b37985ffde2c585d847446d] > > > > [ 422.214479] ? rtw_setassocsta_cmdrsp_callback+0xd0/0xd0 [r8188eu > > > > 91924fe1575bf49b9b37985ffde2c585d847446d] > > > > [ 422.214516] kthread+0x15d/0x190 > > > > [ 422.214523] ? kthread_complete_and_exit+0x20/0x20 > > > > [ 422.214531] ret_from_fork+0x22/0x30 > > > > [ 422.214540] </TASK> > > > > > > Sorry, I am not familiar with KASAN. How should I interpret this output? > > > I see the paragraph above has references to rtw_cmd_thread. I assume > > > that is its way of indicating that rtw_cmd_thread is the cause of the > > > problem, but the one below refers to other functions. I'm not sure where > > > I should start looking. I would start looking at `rtw_sitesurvey_cmd` and > > > `rtw_scan_ch_decision`, which call the memcpy on the > > > rtw_ieee80211_channel structure, but they are not on the call trace. > > > > > > > drivers/staging/r8188eu/core/rtw_cmd.c:276: memcpy() call. > > > > What git hash are you on? Is that the line: > > memcpy(&psurveyPara->ch[i], &ch[i], sizeof(struct ieee80211_channel)); > > Are you sure that's the line which crashes? According to Smatch and my > simple grep that's dead code because "ch" is always NULL. > I don't think Pavel is referring to that line as it belongs to the `rtw_sitesurvey_cmd` function. That func didnt appear in the dmesg output. Rather I think Pavel refers to line 267, which is `memcpy(pcmdbuf, pcmd->parmbuf, pcmd->cmdsz);` from function `rtw_cmd_thread`. Changing rtw_ieee80211_channel to ieee80211_channel must have messed up that line somewhere but I just can't figure out what or why. > > As Michael said the sizes of structures do not mach and the memcpy writes > > below allocated buffer. > > I feel a bit bad for not spotting this in review because I was looking > for that kind of bug. I still don't immediately spot where the bug is. Sorry I put you in this position, Dan. > > regards, > dan carpenter ^ permalink raw reply [flat|nested] 6+ messages in thread
end of thread, other threads:[~2022-04-26 2:48 UTC | newest] Thread overview: 6+ messages (download: mbox.gz / follow: Atom feed) -- links below jump to the message on this page -- 2022-04-24 10:00 [BUG] staging: r8188eu: KASAN: slab-out-of-bounds in rtw_cmd_thread Michael Straube 2022-04-24 12:11 ` Solomon Tan 2022-04-24 15:06 ` Pavel Skripkin 2022-04-25 0:37 ` Solomon Tan 2022-04-25 15:41 ` Dan Carpenter 2022-04-26 2:48 ` Solomon Tan
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