[syzbot] [usb?] KASAN: invalid-free in f_uac1_opts_c_srate_store

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 02dc699f83d0 Merge tag 'kbuild-fixes-7.2-1' of git://git.k..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=16870649580000
kernel config: https://syzkaller.appspot.com/x/.config?x=145fa60d73086782
dashboard link: https://syzkaller.appspot.com/bug?extid=2532c7901f590afd0c3a
compiler: gcc (Debian 14.2.0-19) 14.2.0, GNU ld (GNU Binutils for Debian) 2.44
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=1348e5b9580000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=11aa0db9580000

Downloadable assets:
disk image (non-bootable): https://storage.googleapis.com/syzbot-assets/d900f083ada3/non_bootable_disk-02dc699f.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/faf03a1fb300/vmlinux-02dc699f.xz
kernel image: https://storage.googleapis.com/syzbot-assets/a48e50ceca1d/bzImage-02dc699f.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+2532c7...@syzkaller.appspotmail.com

==================================================================
BUG: KASAN: invalid-free in f_uac1_opts_c_srate_store+0x1d4/0x260 drivers/usb/gadget/function/f_uac1.c:1666
Free of addr ffff88803ea06993 by task syz.0.17/5915

CPU: 0 UID: 0 PID: 5915 Comm: syz.0.17 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120
print_address_description mm/kasan/report.c:378 [inline]
print_report+0x13d/0x4b0 mm/kasan/report.c:482
kasan_report_invalid_free+0xb8/0x190 mm/kasan/report.c:557
check_slab_allocation+0xe1/0xf0 mm/kasan/common.c:230
kasan_slab_pre_free include/linux/kasan.h:199 [inline]
slab_free_hook mm/slub.c:2622 [inline]
slab_free mm/slub.c:6377 [inline]
kfree+0x1b6/0x6c0 mm/slub.c:6692
f_uac1_opts_c_srate_store+0x1d4/0x260 drivers/usb/gadget/function/f_uac1.c:1666
flush_write_buffer fs/configfs/file.c:207 [inline]
configfs_write_iter+0x302/0x4e0 fs/configfs/file.c:229
new_sync_write fs/read_write.c:595 [inline]
vfs_write+0x6ac/0x1050 fs/read_write.c:687
ksys_write+0x12a/0x250 fs/read_write.c:739
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x115/0x870 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f964059e019
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffe2077f218 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007f9640825fa0 RCX: 00007f964059e019
RDX: 0000000000000029 RSI: 0000200000000040 RDI: 0000000000000003
RBP: 00007f964063500c R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f9640825fac R14: 00007f9640825fa0 R15: 00007f9640825fa0
</TASK>

Allocated by task 5915:
kasan_save_stack+0x30/0x50 mm/kasan/common.c:57
kasan_save_track+0x14/0x30 mm/kasan/common.c:78
poison_kmalloc_redzone mm/kasan/common.c:398 [inline]
__kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:415
kasan_kmalloc include/linux/kasan.h:263 [inline]
__do_kmalloc_node mm/slub.c:5334 [inline]
__kmalloc_node_track_caller_noprof+0x331/0x830 mm/slub.c:5471
__kmemdup_nul mm/util.c:64 [inline]
kstrdup+0x51/0xe0 mm/util.c:84
f_uac1_opts_c_srate_store+0x113/0x260 drivers/usb/gadget/function/f_uac1.c:1666
flush_write_buffer fs/configfs/file.c:207 [inline]
configfs_write_iter+0x302/0x4e0 fs/configfs/file.c:229
new_sync_write fs/read_write.c:595 [inline]
vfs_write+0x6ac/0x1050 fs/read_write.c:687
ksys_write+0x12a/0x250 fs/read_write.c:739
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x115/0x870 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f

The buggy address belongs to the object at ffff88803ea06980
which belongs to the cache kmalloc-64 of size 64
The buggy address is located 19 bytes inside of
42-byte region [ffff88803ea06980, ffff88803ea069aa)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff88803ea06880 pfn:0x3ea06
flags: 0xfff00000000200(workingset|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000200 ffff88801bc428c0 ffffea0000d8b290 ffffea0000b89150
raw: ffff88803ea06880 000000080020001d 00000000f5000000 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 0, migratetype Unmovable, gfp_mask 0xd2c40(GFP_NOFS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 5794, tgid 5794 (syz-executor), ts 78142281665, free_ts 78139864775
set_page_owner include/linux/page_owner.h:32 [inline]
post_alloc_hook+0xfd/0x120 mm/page_alloc.c:1859
prep_new_page mm/page_alloc.c:1867 [inline]
get_page_from_freelist+0xf48/0x3530 mm/page_alloc.c:3946
__alloc_frozen_pages_noprof+0x299/0x2dc0 mm/page_alloc.c:5304
alloc_slab_page mm/slub.c:3266 [inline]
allocate_slab mm/slub.c:3380 [inline]
new_slab+0xa2/0x640 mm/slub.c:3426
refill_objects+0xe3/0x410 mm/slub.c:7310
refill_sheaf mm/slub.c:2804 [inline]
__pcs_replace_empty_main+0x376/0x680 mm/slub.c:4675
alloc_from_pcs mm/slub.c:4773 [inline]
slab_alloc_node mm/slub.c:4905 [inline]
__do_kmalloc_node mm/slub.c:5333 [inline]
__kmalloc_noprof+0x66d/0x820 mm/slub.c:5359
_kmalloc_noprof include/linux/slab.h:992 [inline]
_kzalloc_noprof include/linux/slab.h:1309 [inline]
tomoyo_encode2+0xfb/0x3c0 security/tomoyo/realpath.c:45
tomoyo_encode+0x29/0x50 security/tomoyo/realpath.c:80
tomoyo_realpath_from_path+0x18c/0x690 security/tomoyo/realpath.c:283
tomoyo_mount_acl+0x1b6/0x8b0 security/tomoyo/mount.c:107
tomoyo_mount_permission+0x214/0x460 security/tomoyo/mount.c:239
security_sb_mount+0xdd/0x270 security/security.c:1088
path_mount+0x158/0x23d0 fs/namespace.c:4103
do_mount fs/namespace.c:4174 [inline]
__do_sys_mount fs/namespace.c:4390 [inline]
__se_sys_mount fs/namespace.c:4367 [inline]
__x64_sys_mount+0x293/0x310 fs/namespace.c:4367
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x115/0x870 arch/x86/entry/syscall_64.c:94
page last free pid 5794 tgid 5794 stack trace:
reset_page_owner include/linux/page_owner.h:25 [inline]
__free_pages_prepare mm/page_alloc.c:1406 [inline]
__free_frozen_pages+0x79f/0x1090 mm/page_alloc.c:2950
selinux_genfs_get_sid security/selinux/hooks.c:1364 [inline]
inode_doinit_with_dentry+0x99d/0x1320 security/selinux/hooks.c:1563
selinux_d_instantiate+0x26/0x40 security/selinux/hooks.c:6678
security_d_instantiate+0x14c/0x1b0 security/security.c:3704
d_splice_alias_ops+0xd7/0x15c0 fs/dcache.c:3244
proc_sys_lookup+0x319/0x430 fs/proc/proc_sysctl.c:544
__lookup_slow+0x155/0x320 fs/namei.c:1919
lookup_slow+0x50/0x70 fs/namei.c:1936
walk_component fs/namei.c:2282 [inline]
lookup_last fs/namei.c:2789 [inline]
path_lookupat+0x5e8/0xc40 fs/namei.c:2813
filename_lookup+0x202/0x590 fs/namei.c:2842
user_path_at+0x3c/0x60 fs/namei.c:3641
do_mount fs/namespace.c:4171 [inline]
__do_sys_mount fs/namespace.c:4390 [inline]
__se_sys_mount fs/namespace.c:4367 [inline]
__x64_sys_mount+0x1fb/0x310 fs/namespace.c:4367
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x115/0x870 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f

Memory state around the buggy address:
ffff88803ea06880: fa fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
ffff88803ea06900: fa fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
>ffff88803ea06980: 00 00 00 00 00 02 fc fc fc fc fc fc fc fc fc fc
^
ffff88803ea06a00: fa fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
ffff88803ea06a80: fa fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
==================================================================


---
This report is generated by a bot. It may contain errors.
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syzbot engineers can be reached at syzk...@googlegroups.com.

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If the report is already addressed, let syzbot know by replying with:
#syz fix: exact-commit-title

If you want syzbot to run the reproducer, reply with:
#syz test: git://repo/address.git branch-or-commit-hash
If you attach or paste a git patch, syzbot will apply it before testing.

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[syzbot]

For archival purposes, forwarding an incoming command email to
linux-...@vger.kernel.org, syzkall...@googlegroups.com.

***

Subject: [PATCH] Fix invalid-free in f_uac1_opts_c_srate_store
Author: subasr...@gmail.com

#syz test: git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git 5d5fd841c34649f1b09220fe58e59dffd61c447d

Signed-off-by: Subasri S <subasr...@gmail.com>
---
drivers/usb/gadget/function/f_uac1.c | 4 +++-
drivers/usb/gadget/function/f_uac2.c | 4 +++-
2 files changed, 6 insertions(+), 2 deletions(-)

diff --git a/drivers/usb/gadget/function/f_uac1.c b/drivers/usb/gadget/function/f_uac1.c
index 85c502e98f57..488c59fdb2bf 100644
--- a/drivers/usb/gadget/function/f_uac1.c
+++ b/drivers/usb/gadget/function/f_uac1.c
@@ -1595,6 +1595,7 @@ static ssize_t f_uac1_opts_##name##_store(struct config_item *item, \
{ \
struct f_uac1_opts *opts = to_f_uac1_opts(item); \
char *split_page = NULL; \
+ char *original_split_page = NULL; \
int ret = -EINVAL; \
char *token; \
u32 num; \
@@ -1609,6 +1610,7 @@ static ssize_t f_uac1_opts_##name##_store(struct config_item *item, \
i = 0; \
memset(opts->name##s, 0x00, sizeof(opts->name##s)); \
split_page = kstrdup(page, GFP_KERNEL); \
+ original_split_page = split_page; \
while ((token = strsep(&split_page, ",")) != NULL) { \
ret = kstrtou32(token, 0, &num); \
if (ret) \
@@ -1619,7 +1621,7 @@ static ssize_t f_uac1_opts_##name##_store(struct config_item *item, \
}; \
\
end: \
- kfree(split_page); \
+ kfree(original_split_page); \
mutex_unlock(&opts->lock); \
return ret; \
} \
diff --git a/drivers/usb/gadget/function/f_uac2.c b/drivers/usb/gadget/function/f_uac2.c
index 897787d0803c..a0b52c262ad8 100644
--- a/drivers/usb/gadget/function/f_uac2.c
+++ b/drivers/usb/gadget/function/f_uac2.c
@@ -2013,6 +2013,7 @@ static ssize_t f_uac2_opts_##name##_store(struct config_item *item, \
{ \
struct f_uac2_opts *opts = to_f_uac2_opts(item); \
char *split_page = NULL; \
+ char *original_split_page = NULL; \
int ret = -EINVAL; \
char *token; \
u32 num; \
@@ -2027,6 +2028,7 @@ static ssize_t f_uac2_opts_##name##_store(struct config_item *item, \
i = 0; \
memset(opts->name##s, 0x00, sizeof(opts->name##s)); \
split_page = kstrdup(page, GFP_KERNEL); \
+ original_split_page = split_page; \
while ((token = strsep(&split_page, ",")) != NULL) { \
ret = kstrtou32(token, 0, &num); \
if (ret) \
@@ -2037,7 +2039,7 @@ static ssize_t f_uac2_opts_##name##_store(struct config_item *item, \
}; \
\
end: \
- kfree(split_page); \
+ kfree(original_split_page); \
mutex_unlock(&opts->lock); \
return ret; \
} \
--
2.43.0

[syzbot]

Hello,

syzbot tried to test the proposed patch but the build/boot failed:

failed to apply patch:
error: patch failed: drivers/usb/gadget/function/f_uac1.c:1595
error: drivers/usb/gadget/function/f_uac1.c: patch does not apply
error: patch failed: drivers/usb/gadget/function/f_uac2.c:2013
error: drivers/usb/gadget/function/f_uac2.c: patch does not apply



Tested on:

commit: 5d5fd841 Merge 7.2-rc5 into usb-next
git tree: git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git

kernel config: https://syzkaller.appspot.com/x/.config?x=145fa60d73086782
dashboard link: https://syzkaller.appspot.com/bug?extid=2532c7901f590afd0c3a
compiler:

patch: https://syzkaller.appspot.com/x/patch.diff?x=14d9ac9e580000

[syzbot]

For archival purposes, forwarding an incoming command email to
linux-...@vger.kernel.org, syzkall...@googlegroups.com.

***

Subject: [PATCH] Fix invalid-free in f_uac1_opts_c_srate_store
Author: subasr...@gmail.com

#syz test: git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git usb-linus

[syzbot]

Hello,

syzbot has tested the proposed patch and the reproducer did not trigger any issue:

Reported-by: syzbot+2532c7...@syzkaller.appspotmail.com
Tested-by: syzbot+2532c7...@syzkaller.appspotmail.com

Tested on:

commit: f5098b6b Linux 7.2-rc5
git tree: git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git usb-linus
console output: https://syzkaller.appspot.com/x/log.txt?x=16db4649580000

kernel config: https://syzkaller.appspot.com/x/.config?x=145fa60d73086782
dashboard link: https://syzkaller.appspot.com/bug?extid=2532c7901f590afd0c3a

compiler: gcc (Debian 14.2.0-19) 14.2.0, GNU ld (GNU Binutils for Debian) 2.44

patch: https://syzkaller.appspot.com/x/patch.diff?x=1695ac9e580000

Note: testing is done by a robot and is best-effort only.