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[PATCH openEuler-1.0-LTS] erofs: fix pcluster use-after-free on UP platforms
by Zizhi Wo 07 May '24

07 May '24

From: Gao Xiang <hsiangkao(a)linux.alibaba.com> stable inclusion from stable-v5.15.68 commit 8ddd001cef5e82d19192e6861068463ecca5f556 category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/I9LK3Y CVE: CVE-2022-48674 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id… -------------------------------- [ Upstream commit 2f44013e39984c127c6efedf70e6b5f4e9dcf315 ] During stress testing with CONFIG_SMP disabled, KASAN reports as below: ================================================================== BUG: KASAN: use-after-free in __mutex_lock+0xe5/0xc30 Read of size 8 at addr ffff8881094223f8 by task stress/7789 CPU: 0 PID: 7789 Comm: stress Not tainted 6.0.0-rc1-00002-g0d53d2e882f9 #3 Hardware name: Red Hat KVM, BIOS 0.5.1 01/01/2011 Call Trace: <TASK> .. __mutex_lock+0xe5/0xc30 .. z_erofs_do_read_page+0x8ce/0x1560 .. z_erofs_readahead+0x31c/0x580 .. Freed by task 7787 kasan_save_stack+0x1e/0x40 kasan_set_track+0x20/0x30 kasan_set_free_info+0x20/0x40 __kasan_slab_free+0x10c/0x190 kmem_cache_free+0xed/0x380 rcu_core+0x3d5/0xc90 __do_softirq+0x12d/0x389 Last potentially related work creation: kasan_save_stack+0x1e/0x40 __kasan_record_aux_stack+0x97/0xb0 call_rcu+0x3d/0x3f0 erofs_shrink_workstation+0x11f/0x210 erofs_shrink_scan+0xdc/0x170 shrink_slab.constprop.0+0x296/0x530 drop_slab+0x1c/0x70 drop_caches_sysctl_handler+0x70/0x80 proc_sys_call_handler+0x20a/0x2f0 vfs_write+0x555/0x6c0 ksys_write+0xbe/0x160 do_syscall_64+0x3b/0x90 The root cause is that erofs_workgroup_unfreeze() doesn't reset to orig_val thus it causes a race that the pcluster reuses unexpectedly before freeing. Since UP platforms are quite rare now, such path becomes unnecessary. Let's drop such specific-designed path directly instead. Fixes: 73f5c66df3e2 ("staging: erofs: fix `erofs_workgroup_{try_to_freeze, unfreeze}'") Reviewed-by: Yue Hu <huyue2(a)coolpad.com> Reviewed-by: Chao Yu <chao(a)kernel.org> Link: https://lore.kernel.org/r/20220902045710.109530-1-hsiangkao@linux.alibaba.c… Signed-off-by: Gao Xiang <hsiangkao(a)linux.alibaba.com> Signed-off-by: Sasha Levin <sashal(a)kernel.org> Conflicts: fs/erofs/internal.h drivers/staging/erofs/internal.h Signed-off-by: Zizhi Wo <wozizhi(a)huawei.com> --- drivers/staging/erofs/internal.h | 29 ----------------------------- 1 file changed, 29 deletions(-) diff --git a/drivers/staging/erofs/internal.h b/drivers/staging/erofs/internal.h index 8ce37091db20..541326c457f0 100644 --- a/drivers/staging/erofs/internal.h +++ b/drivers/staging/erofs/internal.h @@ -186,7 +186,6 @@ struct erofs_workgroup { #define EROFS_LOCKED_MAGIC (INT_MIN | 0xE0F510CCL) -#if defined(CONFIG_SMP) static inline bool erofs_workgroup_try_to_freeze(struct erofs_workgroup *grp, int val) { @@ -215,34 +214,6 @@ static inline int erofs_wait_on_workgroup_freezed(struct erofs_workgroup *grp) return atomic_cond_read_relaxed(&grp->refcount, VAL != EROFS_LOCKED_MAGIC); } -#else -static inline bool erofs_workgroup_try_to_freeze(struct erofs_workgroup *grp, - int val) -{ - preempt_disable(); - /* no need to spin on UP platforms, let's just disable preemption. */ - if (val != atomic_read(&grp->refcount)) { - preempt_enable(); - return false; - } - return true; -} - -static inline void erofs_workgroup_unfreeze(struct erofs_workgroup *grp, - int orig_val) -{ - preempt_enable(); -} - -static inline int erofs_wait_on_workgroup_freezed(struct erofs_workgroup *grp) -{ - int v = atomic_read(&grp->refcount); - - /* workgroup is never freezed on uniprocessor systems */ - DBG_BUGON(v == EROFS_LOCKED_MAGIC); - return v; -} -#endif static inline bool erofs_workgroup_get(struct erofs_workgroup *grp, int *ocnt) { -- 2.39.2

2 1

[PATCH OLK-6.6] block: fix deadlock between bd_link_disk_holder and partition scan
by Li Nan 07 May '24

07 May '24

mainline inclusion from mainline-v6.9-rc1 commit 03f12122b20b6e6028e9ed69030a49f9cffcbb75 category: bugfix bugzilla: https://gitee.com/openeuler/kernel/issues/I9IVH5 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?… -------------------------------- 'open_mutex' of gendisk is used to protect open/close block devices. But in bd_link_disk_holder(), it is used to protect the creation of symlink between holding disk and slave bdev, which introduces some issues. When bd_link_disk_holder() is called, the driver is usually in the process of initialization/modification and may suspend submitting io. At this time, any io hold 'open_mutex', such as scanning partitions, can cause deadlocks. For example, in raid: T1 T2 bdev_open_by_dev lock open_mutex [1] ... efi_partition ... md_submit_bio md_ioctl mddev_syspend -> suspend all io md_add_new_disk bind_rdev_to_array bd_link_disk_holder try lock open_mutex [2] md_handle_request -> wait mddev_resume T1 scan partition, T2 add a new device to raid. T1 waits for T2 to resume mddev, but T2 waits for open_mutex held by T1. Deadlock occurs. Fix it by introducing a local mutex 'blk_holder_mutex' to replace 'open_mutex'. Fixes: 1b0a2d950ee2 ("md: use new apis to suspend array for ioctls involed array reconfiguration") Reported-by: mgperkow(a)gmail.com Closes: https://bugzilla.kernel.org/show_bug.cgi?id=218459 Signed-off-by: Li Nan <linan122(a)huawei.com> Reviewed-by: Christoph Hellwig <hch(a)lst.de> Reviewed-by: Yu Kuai <yukuai3(a)huawei.com> Link: https://lore.kernel.org/r/20240221090122.1281868-1-linan666@huaweicloud.com Signed-off-by: Jens Axboe <axboe(a)kernel.dk> --- block/holder.c | 12 +++++++----- 1 file changed, 7 insertions(+), 5 deletions(-) diff --git a/block/holder.c b/block/holder.c index 37d18c13d958..791091a7eac2 100644 --- a/block/holder.c +++ b/block/holder.c @@ -8,6 +8,8 @@ struct bd_holder_disk { int refcnt; }; +static DEFINE_MUTEX(blk_holder_mutex); + static struct bd_holder_disk *bd_find_holder_disk(struct block_device *bdev, struct gendisk *disk) { @@ -80,7 +82,7 @@ int bd_link_disk_holder(struct block_device *bdev, struct gendisk *disk) kobject_get(bdev->bd_holder_dir); mutex_unlock(&bdev->bd_disk->open_mutex); - mutex_lock(&disk->open_mutex); + mutex_lock(&blk_holder_mutex); WARN_ON_ONCE(!bdev->bd_holder); holder = bd_find_holder_disk(bdev, disk); @@ -108,7 +110,7 @@ int bd_link_disk_holder(struct block_device *bdev, struct gendisk *disk) goto out_del_symlink; list_add(&holder->list, &disk->slave_bdevs); - mutex_unlock(&disk->open_mutex); + mutex_unlock(&blk_holder_mutex); return 0; out_del_symlink: @@ -116,7 +118,7 @@ int bd_link_disk_holder(struct block_device *bdev, struct gendisk *disk) out_free_holder: kfree(holder); out_unlock: - mutex_unlock(&disk->open_mutex); + mutex_unlock(&blk_holder_mutex); if (ret) kobject_put(bdev->bd_holder_dir); return ret; @@ -140,7 +142,7 @@ void bd_unlink_disk_holder(struct block_device *bdev, struct gendisk *disk) if (WARN_ON_ONCE(!disk->slave_dir)) return; - mutex_lock(&disk->open_mutex); + mutex_lock(&blk_holder_mutex); holder = bd_find_holder_disk(bdev, disk); if (!WARN_ON_ONCE(holder == NULL) && !--holder->refcnt) { del_symlink(disk->slave_dir, bdev_kobj(bdev)); @@ -149,6 +151,6 @@ void bd_unlink_disk_holder(struct block_device *bdev, struct gendisk *disk) list_del_init(&holder->list); kfree(holder); } - mutex_unlock(&disk->open_mutex); + mutex_unlock(&blk_holder_mutex); } EXPORT_SYMBOL_GPL(bd_unlink_disk_holder); -- 2.39.2

2 1

[PATCH OLK-5.10 v2] scsi: core: Fix unremoved procfs host directory regression
by Li Lingfeng 07 May '24

07 May '24

From: "Guilherme G. Piccoli" <gpiccoli(a)igalia.com> stable inclusion from stable-v5.10.215 commit 5c2386ba80e779a92ec3bb64ccadbedd88f779b1 category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/I9HJP4 CVE: CVE-2024-26935 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id… -------------------------------- commit f23a4d6e07570826fe95023ca1aa96a011fa9f84 upstream. Commit fc663711b944 ("scsi: core: Remove the /proc/scsi/${proc_name} directory earlier") fixed a bug related to modules loading/unloading, by adding a call to scsi_proc_hostdir_rm() on scsi_remove_host(). But that led to a potential duplicate call to the hostdir_rm() routine, since it's also called from scsi_host_dev_release(). That triggered a regression report, which was then fixed by commit be03df3d4bfe ("scsi: core: Fix a procfs host directory removal regression"). The fix just dropped the hostdir_rm() call from dev_release(). But it happens that this proc directory is created on scsi_host_alloc(), and that function "pairs" with scsi_host_dev_release(), while scsi_remove_host() pairs with scsi_add_host(). In other words, it seems the reason for removing the proc directory on dev_release() was meant to cover cases in which a SCSI host structure was allocated, but the call to scsi_add_host() didn't happen. And that pattern happens to exist in some error paths, for example. Syzkaller causes that by using USB raw gadget device, error'ing on usb-storage driver, at usb_stor_probe2(). By checking that path, we can see that the BadDevice label leads to a scsi_host_put() after a SCSI host allocation, but there's no call to scsi_add_host() in such path. That leads to messages like this in dmesg (and a leak of the SCSI host proc structure): usb-storage 4-1:87.51: USB Mass Storage device detected proc_dir_entry 'scsi/usb-storage' already registered WARNING: CPU: 1 PID: 3519 at fs/proc/generic.c:377 proc_register+0x347/0x4e0 fs/proc/generic.c:376 The proper fix seems to still call scsi_proc_hostdir_rm() on dev_release(), but guard that with the state check for SHOST_CREATED; there is even a comment in scsi_host_dev_release() detailing that: such conditional is meant for cases where the SCSI host was allocated but there was no calls to {add,remove}_host(), like the usb-storage case. This is what we propose here and with that, the error path of usb-storage does not trigger the warning anymore. Reported-by: syzbot+c645abf505ed21f931b5(a)syzkaller.appspotmail.com Fixes: be03df3d4bfe ("scsi: core: Fix a procfs host directory removal regression") Cc: stable(a)vger.kernel.org Cc: Bart Van Assche <bvanassche(a)acm.org> Cc: John Garry <john.g.garry(a)oracle.com> Cc: Shin'ichiro Kawasaki <shinichiro.kawasaki(a)wdc.com> Signed-off-by: Guilherme G. Piccoli <gpiccoli(a)igalia.com> Link: https://lore.kernel.org/r/20240313113006.2834799-1-gpiccoli@igalia.com Reviewed-by: Bart Van Assche <bvanassche(a)acm.org> Signed-off-by: Martin K. Petersen <martin.petersen(a)oracle.com> Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org> Signed-off-by: Li Lingfeng <lilingfeng3(a)huawei.com> --- v1->v2: Add CVE num in commit message. drivers/scsi/hosts.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) diff --git a/drivers/scsi/hosts.c b/drivers/scsi/hosts.c index 5bac4936c647..3feaa61f948f 100644 --- a/drivers/scsi/hosts.c +++ b/drivers/scsi/hosts.c @@ -334,12 +334,13 @@ static void scsi_host_dev_release(struct device *dev) if (shost->shost_state == SHOST_CREATED) { /* - * Free the shost_dev device name here if scsi_host_alloc() - * and scsi_host_put() have been called but neither + * Free the shost_dev device name and remove the proc host dir + * here if scsi_host_{alloc,put}() have been called but neither * scsi_host_add() nor scsi_host_remove() has been called. * This avoids that the memory allocated for the shost_dev - * name is leaked. + * name as well as the proc dir structure are leaked. */ + scsi_proc_hostdir_rm(shost->hostt); kfree(dev_name(&shost->shost_dev)); } -- 2.31.1

2 1

[PATCH openEuler-1.0-LTS] ALSA: emu10k1: Fix out of bounds access in snd_emu10k1_pcm_channel_alloc()
by Zhang Xiaoxu 07 May '24

07 May '24

From: Tasos Sahanidis <tasos(a)tasossah.com> mainline inclusion from mainline-v6.0-rc5 commit d29f59051d3a07b81281b2df2b8c9dfe4716067f category: bugfix bugzilla: NA CVE: CVE-2022-48702 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?… --------------------------- The voice allocator sometimes begins allocating from near the end of the array and then wraps around, however snd_emu10k1_pcm_channel_alloc() accesses the newly allocated voices as if it never wrapped around. This results in out of bounds access if the first voice has a high enough index so that first_voice + requested_voice_count > NUM_G (64). The more voices are requested, the more likely it is for this to occur. This was initially discovered using PipeWire, however it can be reproduced by calling aplay multiple times with 16 channels: aplay -r 48000 -D plughw:CARD=Live,DEV=3 -c 16 /dev/zero UBSAN: array-index-out-of-bounds in sound/pci/emu10k1/emupcm.c:127:40 index 65 is out of range for type 'snd_emu10k1_voice [64]' CPU: 1 PID: 31977 Comm: aplay Tainted: G W IOE 6.0.0-rc2-emu10k1+ #7 Hardware name: ASUSTEK COMPUTER INC P5W DH Deluxe/P5W DH Deluxe, BIOS 3002 07/22/2010 Call Trace: <TASK> dump_stack_lvl+0x49/0x63 dump_stack+0x10/0x16 ubsan_epilogue+0x9/0x3f __ubsan_handle_out_of_bounds.cold+0x44/0x49 snd_emu10k1_playback_hw_params+0x3bc/0x420 [snd_emu10k1] snd_pcm_hw_params+0x29f/0x600 [snd_pcm] snd_pcm_common_ioctl+0x188/0x1410 [snd_pcm] ? exit_to_user_mode_prepare+0x35/0x170 ? do_syscall_64+0x69/0x90 ? syscall_exit_to_user_mode+0x26/0x50 ? do_syscall_64+0x69/0x90 ? exit_to_user_mode_prepare+0x35/0x170 snd_pcm_ioctl+0x27/0x40 [snd_pcm] __x64_sys_ioctl+0x95/0xd0 do_syscall_64+0x5c/0x90 ? do_syscall_64+0x69/0x90 ? do_syscall_64+0x69/0x90 entry_SYSCALL_64_after_hwframe+0x63/0xcd Signed-off-by: Tasos Sahanidis <tasos(a)tasossah.com> Cc: <stable(a)vger.kernel.org> Link: https://lore.kernel.org/r/3707dcab-320a-62ff-63c0-73fc201ef756@tasossah.com Signed-off-by: Takashi Iwai <tiwai(a)suse.de> Signed-off-by: Zhang Xiaoxu <zhangxiaoxu5(a)huawei.com> --- sound/pci/emu10k1/emupcm.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/sound/pci/emu10k1/emupcm.c b/sound/pci/emu10k1/emupcm.c index 9f2b6097f486..623776b13f8d 100644 --- a/sound/pci/emu10k1/emupcm.c +++ b/sound/pci/emu10k1/emupcm.c @@ -137,7 +137,7 @@ static int snd_emu10k1_pcm_channel_alloc(struct snd_emu10k1_pcm * epcm, int voic epcm->voices[0]->epcm = epcm; if (voices > 1) { for (i = 1; i < voices; i++) { - epcm->voices[i] = &epcm->emu->voices[epcm->voices[0]->number + i]; + epcm->voices[i] = &epcm->emu->voices[(epcm->voices[0]->number + i) % NUM_G]; epcm->voices[i]->epcm = epcm; } } -- 2.34.1

2 1

[PATCH OLK-5.10] scsi: core: Fix unremoved procfs host directory regression
by Li Lingfeng 07 May '24

07 May '24

From: "Guilherme G. Piccoli" <gpiccoli(a)igalia.com> stable inclusion from stable-v5.10.215 commit 5c2386ba80e779a92ec3bb64ccadbedd88f779b1 category: bugfix bugzilla: 189877 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id… -------------------------------- commit f23a4d6e07570826fe95023ca1aa96a011fa9f84 upstream. Commit fc663711b944 ("scsi: core: Remove the /proc/scsi/${proc_name} directory earlier") fixed a bug related to modules loading/unloading, by adding a call to scsi_proc_hostdir_rm() on scsi_remove_host(). But that led to a potential duplicate call to the hostdir_rm() routine, since it's also called from scsi_host_dev_release(). That triggered a regression report, which was then fixed by commit be03df3d4bfe ("scsi: core: Fix a procfs host directory removal regression"). The fix just dropped the hostdir_rm() call from dev_release(). But it happens that this proc directory is created on scsi_host_alloc(), and that function "pairs" with scsi_host_dev_release(), while scsi_remove_host() pairs with scsi_add_host(). In other words, it seems the reason for removing the proc directory on dev_release() was meant to cover cases in which a SCSI host structure was allocated, but the call to scsi_add_host() didn't happen. And that pattern happens to exist in some error paths, for example. Syzkaller causes that by using USB raw gadget device, error'ing on usb-storage driver, at usb_stor_probe2(). By checking that path, we can see that the BadDevice label leads to a scsi_host_put() after a SCSI host allocation, but there's no call to scsi_add_host() in such path. That leads to messages like this in dmesg (and a leak of the SCSI host proc structure): usb-storage 4-1:87.51: USB Mass Storage device detected proc_dir_entry 'scsi/usb-storage' already registered WARNING: CPU: 1 PID: 3519 at fs/proc/generic.c:377 proc_register+0x347/0x4e0 fs/proc/generic.c:376 The proper fix seems to still call scsi_proc_hostdir_rm() on dev_release(), but guard that with the state check for SHOST_CREATED; there is even a comment in scsi_host_dev_release() detailing that: such conditional is meant for cases where the SCSI host was allocated but there was no calls to {add,remove}_host(), like the usb-storage case. This is what we propose here and with that, the error path of usb-storage does not trigger the warning anymore. Reported-by: syzbot+c645abf505ed21f931b5(a)syzkaller.appspotmail.com Fixes: be03df3d4bfe ("scsi: core: Fix a procfs host directory removal regression") Cc: stable(a)vger.kernel.org Cc: Bart Van Assche <bvanassche(a)acm.org> Cc: John Garry <john.g.garry(a)oracle.com> Cc: Shin'ichiro Kawasaki <shinichiro.kawasaki(a)wdc.com> Signed-off-by: Guilherme G. Piccoli <gpiccoli(a)igalia.com> Link: https://lore.kernel.org/r/20240313113006.2834799-1-gpiccoli@igalia.com Reviewed-by: Bart Van Assche <bvanassche(a)acm.org> Signed-off-by: Martin K. Petersen <martin.petersen(a)oracle.com> Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org> Signed-off-by: Li Lingfeng <lilingfeng3(a)huawei.com> --- drivers/scsi/hosts.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) diff --git a/drivers/scsi/hosts.c b/drivers/scsi/hosts.c index 5bac4936c647..3feaa61f948f 100644 --- a/drivers/scsi/hosts.c +++ b/drivers/scsi/hosts.c @@ -334,12 +334,13 @@ static void scsi_host_dev_release(struct device *dev) if (shost->shost_state == SHOST_CREATED) { /* - * Free the shost_dev device name here if scsi_host_alloc() - * and scsi_host_put() have been called but neither + * Free the shost_dev device name and remove the proc host dir + * here if scsi_host_{alloc,put}() have been called but neither * scsi_host_add() nor scsi_host_remove() has been called. * This avoids that the memory allocated for the shost_dev - * name is leaked. + * name as well as the proc dir structure are leaked. */ + scsi_proc_hostdir_rm(shost->hostt); kfree(dev_name(&shost->shost_dev)); } -- 2.31.1

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[PATCH OLK-5.10 0/1] CVE-2023-52650
by Yuntao Liu 07 May '24

07 May '24

CVE-2023-52650 Chen Ni (1): [Backport] drm/tegra: dsi: Add missing check for of_find_device_by_node drivers/gpu/drm/tegra/dsi.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) -- 2.34.1

2 2

[PATCH openEuler-1.0-LTS 0/1] CVE-2023-52650
by Yuntao Liu 07 May '24

07 May '24

CVE-2023-52650 Chen Ni (1): [Backport] drm/tegra: dsi: Add missing check for of_find_device_by_node drivers/gpu/drm/tegra/dsi.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) -- 2.34.1

2 2

[PATCH OLK-5.10] fs: sysfs: Fix reference leak in sysfs_break_active_protection()
by Yifan Qiao 07 May '24

07 May '24

From: Alan Stern <stern(a)rowland.harvard.edu> stable inclusion from stable-v6.8.8 commit a4c99b57d43bab45225ba92d574a8683f9edc8e4 category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/I9L5IQ CVE: CVE-2024-26993 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id… -------------------------------- commit a90bca2228c0646fc29a72689d308e5fe03e6d78 upstream. The sysfs_break_active_protection() routine has an obvious reference leak in its error path. If the call to kernfs_find_and_get() fails then kn will be NULL, so the companion sysfs_unbreak_active_protection() routine won't get called (and would only cause an access violation by trying to dereference kn->parent if it was called). As a result, the reference to kobj acquired at the start of the function will never be released. Fix the leak by adding an explicit kobject_put() call when kn is NULL. Signed-off-by: Alan Stern <stern(a)rowland.harvard.edu> Fixes: 2afc9166f79b ("scsi: sysfs: Introduce sysfs_{un,}break_active_protection()") Cc: Bart Van Assche <bvanassche(a)acm.org> Cc: stable(a)vger.kernel.org Reviewed-by: Bart Van Assche <bvanassche(a)acm.org> Acked-by: Tejun Heo <tj(a)kernel.org> Link: https://lore.kernel.org/r/8a4d3f0f-c5e3-4b70-a188-0ca433f9e6f9@rowland.harv… Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org> Signed-off-by: Yifan Qiao <qiaoyifan4(a)huawei.com> --- fs/sysfs/file.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/fs/sysfs/file.c b/fs/sysfs/file.c index a12ac0356c69..f21e73d10724 100644 --- a/fs/sysfs/file.c +++ b/fs/sysfs/file.c @@ -450,6 +450,8 @@ struct kernfs_node *sysfs_break_active_protection(struct kobject *kobj, kn = kernfs_find_and_get(kobj->sd, attr->name); if (kn) kernfs_break_active_protection(kn); + else + kobject_put(kobj); return kn; } EXPORT_SYMBOL_GPL(sysfs_break_active_protection); -- 2.39.2

2 1

[PATCH OLK-6.6] fs: sysfs: Fix reference leak in sysfs_break_active_protection()
by Yifan Qiao 07 May '24

07 May '24

From: Alan Stern <stern(a)rowland.harvard.edu> stable inclusion from stable-v6.8.8 commit a4c99b57d43bab45225ba92d574a8683f9edc8e4 category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/I9L5IQ CVE: CVE-2024-26993 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id… -------------------------------- commit a90bca2228c0646fc29a72689d308e5fe03e6d78 upstream. The sysfs_break_active_protection() routine has an obvious reference leak in its error path. If the call to kernfs_find_and_get() fails then kn will be NULL, so the companion sysfs_unbreak_active_protection() routine won't get called (and would only cause an access violation by trying to dereference kn->parent if it was called). As a result, the reference to kobj acquired at the start of the function will never be released. Fix the leak by adding an explicit kobject_put() call when kn is NULL. Signed-off-by: Alan Stern <stern(a)rowland.harvard.edu> Fixes: 2afc9166f79b ("scsi: sysfs: Introduce sysfs_{un,}break_active_protection()") Cc: Bart Van Assche <bvanassche(a)acm.org> Cc: stable(a)vger.kernel.org Reviewed-by: Bart Van Assche <bvanassche(a)acm.org> Acked-by: Tejun Heo <tj(a)kernel.org> Link: https://lore.kernel.org/r/8a4d3f0f-c5e3-4b70-a188-0ca433f9e6f9@rowland.harv… Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org> Signed-off-by: Yifan Qiao <qiaoyifan4(a)huawei.com> --- fs/sysfs/file.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/fs/sysfs/file.c b/fs/sysfs/file.c index a12ac0356c69..f21e73d10724 100644 --- a/fs/sysfs/file.c +++ b/fs/sysfs/file.c @@ -450,6 +450,8 @@ struct kernfs_node *sysfs_break_active_protection(struct kobject *kobj, kn = kernfs_find_and_get(kobj->sd, attr->name); if (kn) kernfs_break_active_protection(kn); + else + kobject_put(kobj); return kn; } EXPORT_SYMBOL_GPL(sysfs_break_active_protection); -- 2.39.2

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[PATCH openEuler-1.0-LTS] fs: sysfs: Fix reference leak in sysfs_break_active_protection()
by Yifan Qiao 07 May '24

07 May '24

From: Alan Stern <stern(a)rowland.harvard.edu> stable inclusion from stable-v6.8.8 commit a4c99b57d43bab45225ba92d574a8683f9edc8e4 category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/I9L5IQ CVE: CVE-2024-26993 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id… -------------------------------- commit a90bca2228c0646fc29a72689d308e5fe03e6d78 upstream. The sysfs_break_active_protection() routine has an obvious reference leak in its error path. If the call to kernfs_find_and_get() fails then kn will be NULL, so the companion sysfs_unbreak_active_protection() routine won't get called (and would only cause an access violation by trying to dereference kn->parent if it was called). As a result, the reference to kobj acquired at the start of the function will never be released. Fix the leak by adding an explicit kobject_put() call when kn is NULL. Signed-off-by: Alan Stern <stern(a)rowland.harvard.edu> Fixes: 2afc9166f79b ("scsi: sysfs: Introduce sysfs_{un,}break_active_protection()") Cc: Bart Van Assche <bvanassche(a)acm.org> Cc: stable(a)vger.kernel.org Reviewed-by: Bart Van Assche <bvanassche(a)acm.org> Acked-by: Tejun Heo <tj(a)kernel.org> Link: https://lore.kernel.org/r/8a4d3f0f-c5e3-4b70-a188-0ca433f9e6f9@rowland.harv… Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org> Signed-off-by: Yifan Qiao <qiaoyifan4(a)huawei.com> --- fs/sysfs/file.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/fs/sysfs/file.c b/fs/sysfs/file.c index a12ac0356c69..f21e73d10724 100644 --- a/fs/sysfs/file.c +++ b/fs/sysfs/file.c @@ -450,6 +450,8 @@ struct kernfs_node *sysfs_break_active_protection(struct kobject *kobj, kn = kernfs_find_and_get(kobj->sd, attr->name); if (kn) kernfs_break_active_protection(kn); + else + kobject_put(kobj); return kn; } EXPORT_SYMBOL_GPL(sysfs_break_active_protection); -- 2.39.2

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