May 2024 - Kernel - mailweb.openeuler.org

[PATCH OLK-5.10] KVM: SVM: Flush pages under kvm->lock to fix UAF in svm_register_enc_region()
by Ye Bin 21 May '24

21 May '24

From: Sean Christopherson <seanjc(a)google.com> mainline inclusion from mainline-v6.8 commit 5ef1d8c1ddbf696e47b226e11888eaf8d9e8e807 category: bugfix CVE: CVE-2024-35791 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?… -------------------------------- Do the cache flush of converted pages in svm_register_enc_region() before dropping kvm->lock to fix use-after-free issues where region and/or its array of pages could be freed by a different task, e.g. if userspace has __unregister_enc_region_locked() already queued up for the region. Note, the "obvious" alternative of using local variables doesn't fully resolve the bug, as region->pages is also dynamically allocated. I.e. the region structure itself would be fine, but region->pages could be freed. Flushing multiple pages under kvm->lock is unfortunate, but the entire flow is a rare slow path, and the manual flush is only needed on CPUs that lack coherency for encrypted memory. Fixes: 19a23da53932 ("Fix unsynchronized access to sev members through svm_register_enc_region") Reported-by: Gabe Kirkpatrick <gkirkpatrick(a)google.com> Cc: Josh Eads <josheads(a)google.com> Cc: Peter Gonda <pgonda(a)google.com> Cc: stable(a)vger.kernel.org Signed-off-by: Sean Christopherson <seanjc(a)google.com> Message-Id: <20240217013430.2079561-1-seanjc(a)google.com> Signed-off-by: Paolo Bonzini <pbonzini(a)redhat.com> Signed-off-by: Ye Bin <yebin10(a)huawei.com> --- arch/x86/kvm/svm/sev.c | 16 +++++++++------- 1 file changed, 9 insertions(+), 7 deletions(-) diff --git a/arch/x86/kvm/svm/sev.c b/arch/x86/kvm/svm/sev.c index c2b34998c27d..52e14d6aa496 100644 --- a/arch/x86/kvm/svm/sev.c +++ b/arch/x86/kvm/svm/sev.c @@ -1024,20 +1024,22 @@ int svm_register_enc_region(struct kvm *kvm, goto e_free; } - region->uaddr = range->addr; - region->size = range->size; - - list_add_tail(&region->list, &sev->regions_list); - mutex_unlock(&kvm->lock); - /* * The guest may change the memory encryption attribute from C=0 -> C=1 * or vice versa for this memory range. Lets make sure caches are * flushed to ensure that guest data gets written into memory with - * correct C-bit. + * correct C-bit. Note, this must be done before dropping kvm->lock, + * as region and its array of pages can be freed by a different task + * once kvm->lock is released. */ sev_clflush_pages(region->pages, region->npages); + region->uaddr = range->addr; + region->size = range->size; + + list_add_tail(&region->list, &sev->regions_list); + mutex_unlock(&kvm->lock); + return ret; e_free: -- 2.31.1

2 1

[PATCH OLK-5.10] btrfs: handle chunk tree lookup error in btrfs_relocate_sys_chunks()
by Yifan Qiao 21 May '24

21 May '24

From: David Sterba <dsterba(a)suse.com> stable inclusion from stable-v5.4.274 commit 576164bd01bd795f8b09fb194b493103506b33c9 category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/I9QGIP CVE: CVE-2024-35936 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id… -------------------------------- [ Upstream commit 7411055db5ce64f836aaffd422396af0075fdc99 ] The unhandled case in btrfs_relocate_sys_chunks() loop is a corruption, as it could be caused only by two impossible conditions: - at first the search key is set up to look for a chunk tree item, with offset -1, this is an inexact search and the key->offset will contain the correct offset upon a successful search, a valid chunk tree item cannot have an offset -1 - after first successful search, the found_key corresponds to a chunk item, the offset is decremented by 1 before the next loop, it's impossible to find a chunk item there due to alignment and size constraints Reviewed-by: Josef Bacik <josef(a)toxicpanda.com> Reviewed-by: Anand Jain <anand.jain(a)oracle.com> Signed-off-by: David Sterba <dsterba(a)suse.com> Signed-off-by: Sasha Levin <sashal(a)kernel.org> Signed-off-by: Yifan Qiao <qiaoyifan4(a)huawei.com> --- fs/btrfs/volumes.c | 12 +++++++++++- 1 file changed, 11 insertions(+), 1 deletion(-) diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c index eaf5cd043dac..634b73d734bc 100644 --- a/fs/btrfs/volumes.c +++ b/fs/btrfs/volumes.c @@ -3178,7 +3178,17 @@ static int btrfs_relocate_sys_chunks(struct btrfs_fs_info *fs_info) mutex_unlock(&fs_info->delete_unused_bgs_mutex); goto error; } - BUG_ON(ret == 0); /* Corruption */ + if (ret == 0) { + /* + * On the first search we would find chunk tree with + * offset -1, which is not possible. On subsequent + * loops this would find an existing item on an invalid + * offset (one less than the previous one, wrong + * alignment and size). + */ + ret = -EUCLEAN; + goto error; + } ret = btrfs_previous_item(chunk_root, path, key.objectid, key.type); -- 2.39.2

2 1

[PATCH openEuler-1.0-LTS] btrfs: handle chunk tree lookup error in btrfs_relocate_sys_chunks()
by Yifan Qiao 21 May '24

21 May '24

From: David Sterba <dsterba(a)suse.com> stable inclusion from stable-v5.4.274 commit 576164bd01bd795f8b09fb194b493103506b33c9 category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/I9QGIP CVE: CVE-2024-35936 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id… -------------------------------- [ Upstream commit 7411055db5ce64f836aaffd422396af0075fdc99 ] The unhandled case in btrfs_relocate_sys_chunks() loop is a corruption, as it could be caused only by two impossible conditions: - at first the search key is set up to look for a chunk tree item, with offset -1, this is an inexact search and the key->offset will contain the correct offset upon a successful search, a valid chunk tree item cannot have an offset -1 - after first successful search, the found_key corresponds to a chunk item, the offset is decremented by 1 before the next loop, it's impossible to find a chunk item there due to alignment and size constraints Reviewed-by: Josef Bacik <josef(a)toxicpanda.com> Reviewed-by: Anand Jain <anand.jain(a)oracle.com> Signed-off-by: David Sterba <dsterba(a)suse.com> Signed-off-by: Sasha Levin <sashal(a)kernel.org> Signed-off-by: Yifan Qiao <qiaoyifan4(a)huawei.com> --- fs/btrfs/volumes.c | 12 +++++++++++- 1 file changed, 11 insertions(+), 1 deletion(-) diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c index 054468e43228..172cec8a12dd 100644 --- a/fs/btrfs/volumes.c +++ b/fs/btrfs/volumes.c @@ -2922,7 +2922,17 @@ static int btrfs_relocate_sys_chunks(struct btrfs_fs_info *fs_info) mutex_unlock(&fs_info->delete_unused_bgs_mutex); goto error; } - BUG_ON(ret == 0); /* Corruption */ + if (ret == 0) { + /* + * On the first search we would find chunk tree with + * offset -1, which is not possible. On subsequent + * loops this would find an existing item on an invalid + * offset (one less than the previous one, wrong + * alignment and size). + */ + ret = -EUCLEAN; + goto error; + } ret = btrfs_previous_item(chunk_root, path, key.objectid, key.type); -- 2.39.2

2 1

[PATCH OLK-5.10] KVM: SVM: Flush pages under kvm->lock to fix UAF in svm_register_enc_region()
by Ye Bin 21 May '24

21 May '24

From: Sean Christopherson <seanjc(a)google.com> mainline inclusion from mainline-v6.8 commit 5ef1d8c1ddbf696e47b226e11888eaf8d9e8e807 category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/I9Q8ZA Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?… -------------------------------- Do the cache flush of converted pages in svm_register_enc_region() before dropping kvm->lock to fix use-after-free issues where region and/or its array of pages could be freed by a different task, e.g. if userspace has __unregister_enc_region_locked() already queued up for the region. Note, the "obvious" alternative of using local variables doesn't fully resolve the bug, as region->pages is also dynamically allocated. I.e. the region structure itself would be fine, but region->pages could be freed. Flushing multiple pages under kvm->lock is unfortunate, but the entire flow is a rare slow path, and the manual flush is only needed on CPUs that lack coherency for encrypted memory. Fixes: 19a23da53932 ("Fix unsynchronized access to sev members through svm_register_enc_region") Reported-by: Gabe Kirkpatrick <gkirkpatrick(a)google.com> Cc: Josh Eads <josheads(a)google.com> Cc: Peter Gonda <pgonda(a)google.com> Cc: stable(a)vger.kernel.org Signed-off-by: Sean Christopherson <seanjc(a)google.com> Message-Id: <20240217013430.2079561-1-seanjc(a)google.com> Signed-off-by: Paolo Bonzini <pbonzini(a)redhat.com> Signed-off-by: Ye Bin <yebin10(a)huawei.com> --- arch/x86/kvm/svm/sev.c | 16 +++++++++------- 1 file changed, 9 insertions(+), 7 deletions(-) diff --git a/arch/x86/kvm/svm/sev.c b/arch/x86/kvm/svm/sev.c index c2b34998c27d..52e14d6aa496 100644 --- a/arch/x86/kvm/svm/sev.c +++ b/arch/x86/kvm/svm/sev.c @@ -1024,20 +1024,22 @@ int svm_register_enc_region(struct kvm *kvm, goto e_free; } - region->uaddr = range->addr; - region->size = range->size; - - list_add_tail(&region->list, &sev->regions_list); - mutex_unlock(&kvm->lock); - /* * The guest may change the memory encryption attribute from C=0 -> C=1 * or vice versa for this memory range. Lets make sure caches are * flushed to ensure that guest data gets written into memory with - * correct C-bit. + * correct C-bit. Note, this must be done before dropping kvm->lock, + * as region and its array of pages can be freed by a different task + * once kvm->lock is released. */ sev_clflush_pages(region->pages, region->npages); + region->uaddr = range->addr; + region->size = range->size; + + list_add_tail(&region->list, &sev->regions_list); + mutex_unlock(&kvm->lock); + return ret; e_free: -- 2.31.1

2 1

[PATCH OLK-5.10 0/1] Fix allmodconfig build error
by Shuai Wu 21 May '24

21 May '24

Fix allmodconfig build error in hiroce3 driver. Shuai Wu (1): net/ethernet/huawei/hiroce3: Fix allmodconfig build error .../hw/hiroce3/bond/roce_bond_common.c | 38 +- .../hw/hiroce3/cq/roce_cq_destroy.c | 15 +- .../hw/hiroce3/host/hmm/hmm_comp_mtt.c | 1 + .../hw/hiroce3/host/hmm/hmm_comp_mw_mr.c | 1 + .../hw/hiroce3/host/hmm/hmm_comp_res.c | 1 + .../infiniband/hw/hiroce3/host/hmm/hmm_mr.c | 98 +---- .../infiniband/hw/hiroce3/host/hmm/hmm_umem.c | 4 +- .../infiniband/hw/hiroce3/host/hmm/hmm_umem.h | 2 +- .../include/rdma/rdma_context_format.h | 4 +- .../include/rdma/rdma_ext_ctx_format.h | 5 +- .../hw/hiroce3/include/rdma/roce_ccf_format.h | 4 +- .../hw/hiroce3/include/rdma/roce_verbs_attr.h | 4 +- .../include/rdma/roce_verbs_attr_qpc_chip.h | 4 +- .../hiroce3/include/rdma/roce_verbs_cq_attr.h | 4 +- .../include/rdma/roce_verbs_ext_attr.h | 4 +- .../include/rdma/roce_verbs_gid_attr.h | 4 +- .../hiroce3/include/rdma/roce_verbs_mr_attr.h | 4 +- .../hw/hiroce3/include/rdma/roce_verbs_pub.h | 4 +- .../include/rdma/roce_verbs_srq_attr.h | 4 +- drivers/infiniband/hw/hiroce3/mr/roce_mr.c | 37 -- drivers/infiniband/hw/hiroce3/roce.h | 1 - drivers/infiniband/hw/hiroce3/roce_main.c | 7 +- .../ethernet/huawei/hinic3/bond/hinic3_bond.c | 1 - .../ethernet/huawei/hinic3/bond/hinic3_bond.h | 4 +- .../ethernet/huawei/hinic3/cqm/cqm_bat_cla.c | 198 +++------ .../huawei/hinic3/cqm/cqm_bitmap_table.c | 10 +- .../huawei/hinic3/cqm/cqm_bloomfilter.c | 69 +--- .../net/ethernet/huawei/hinic3/cqm/cqm_cmd.c | 139 ++----- .../net/ethernet/huawei/hinic3/cqm/cqm_cmd.h | 2 - .../net/ethernet/huawei/hinic3/cqm/cqm_db.c | 192 +++------ .../ethernet/huawei/hinic3/cqm/cqm_define.h | 4 - .../net/ethernet/huawei/hinic3/cqm/cqm_main.c | 178 +++------ .../ethernet/huawei/hinic3/cqm/cqm_object.c | 378 +++++------------- .../huawei/hinic3/cqm/cqm_object_intern.c | 194 +++------ .../ethernet/huawei/hinic3/hw/hinic3_hw_cfg.c | 2 +- .../ethernet/huawei/hinic3/hw/hinic3_hwif.c | 38 -- .../huawei/hinic3/hw/hinic3_multi_host_mgmt.c | 56 ++- .../hinic3/include/bond/bond_common_defs.h | 4 +- .../huawei/hinic3/include/hinic3_common.h | 2 - .../huawei/hinic3/include/hinic3_cqm.h | 11 - .../huawei/hinic3/include/hinic3_cqm_define.h | 4 - .../include/mpu/mpu_outband_ncsi_cmd_defs.h | 4 +- 42 files changed, 474 insertions(+), 1266 deletions(-) -- 2.33.0

2 2

[PATCH OLK-5.10] ALSA: scarlett2: Add clamp() in scarlett2_mixer_ctl_put()
by felix 21 May '24

21 May '24

From: "Geoffrey D. Bennett" <g(a)b4.vu> stable inclusion from stable-v5.15.148 commit e517645ead5ea22c69d2a44694baa23fe1ce7c2b category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/I9Q9ID CVE: CVE-2023-52674 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id… -------------------------------- [ Upstream commit 04f8f053252b86c7583895c962d66747ecdc61b7 ] Ensure the value passed to scarlett2_mixer_ctl_put() is between 0 and SCARLETT2_MIXER_MAX_VALUE so we don't attempt to access outside scarlett2_mixer_values[]. Signed-off-by: Geoffrey D. Bennett <g(a)b4.vu> Fixes: 9e4d5c1be21f ("ALSA: usb-audio: Scarlett Gen 2 mixer interface") Link: https://lore.kernel.org/r/3b19fb3da641b587749b85fe1daa1b4e696c0c1b.17030010… Signed-off-by: Takashi Iwai <tiwai(a)suse.de> Signed-off-by: Sasha Levin <sashal(a)kernel.org> Conflicts: sound/usb/mixer_scarlett_gen2.c [Some context inconsistencies exist in the scarlett2_mixer_ctl_put function, which does not affect the patch] Signed-off-by: Felix Fu <fuzhen5(a)huawei.com> --- sound/usb/mixer_scarlett_gen2.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/sound/usb/mixer_scarlett_gen2.c b/sound/usb/mixer_scarlett_gen2.c index 1b7c7b754c38..6b7c8b8d7111 100644 --- a/sound/usb/mixer_scarlett_gen2.c +++ b/sound/usb/mixer_scarlett_gen2.c @@ -1509,7 +1509,8 @@ static int scarlett2_mixer_ctl_put(struct snd_kcontrol *kctl, mutex_lock(&private->data_mutex); oval = private->mix[elem->control]; - val = ucontrol->value.integer.value[0]; + val = clamp(ucontrol->value.integer.value[0], + 0L, (long)SCARLETT2_MIXER_MAX_VALUE); num_mixer_in = ports[SCARLETT2_PORT_TYPE_MIX].num[SCARLETT2_PORT_OUT]; mix_num = elem->control / num_mixer_in; -- 2.34.1

2 1

[PATCH OLK-5.10] hwrng: core - Fix page fault dead lock on mmap-ed hwrng
by Guo Mengqi 21 May '24

21 May '24

From: Herbert Xu <herbert(a)gondor.apana.org.au> stable inclusion from stable-v5.10.210 commit c6a8111aacbfe7a8a70f46cc0de8eed00561693c category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/I99JR3 CVE: CVE-2023-52615 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id… -------------------------------- commit 78aafb3884f6bc6636efcc1760c891c8500b9922 upstream. There is a dead-lock in the hwrng device read path. This triggers when the user reads from /dev/hwrng into memory also mmap-ed from /dev/hwrng. The resulting page fault triggers a recursive read which then dead-locks. Fix this by using a stack buffer when calling copy_to_user. Reported-by: Edward Adam Davis <eadavis(a)qq.com> Reported-by: syzbot+c52ab18308964d248092(a)syzkaller.appspotmail.com Fixes: 9996508b3353 ("hwrng: core - Replace u32 in driver API with byte array") Cc: <stable(a)vger.kernel.org> Signed-off-by: Herbert Xu <herbert(a)gondor.apana.org.au> Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org> Signed-off-by: Yi Yang <yiyang13(a)huawei.com> --- drivers/char/hw_random/core.c | 34 +++++++++++++++++++++------------- 1 file changed, 21 insertions(+), 13 deletions(-) diff --git a/drivers/char/hw_random/core.c b/drivers/char/hw_random/core.c index 5749998feaa4..6e2c1ba18012 100644 --- a/drivers/char/hw_random/core.c +++ b/drivers/char/hw_random/core.c @@ -24,10 +24,13 @@ #include <linux/random.h> #include <linux/sched.h> #include <linux/slab.h> +#include <linux/string.h> #include <linux/uaccess.h> #define RNG_MODULE_NAME "hw_random" +#define RNG_BUFFER_SIZE (SMP_CACHE_BYTES < 32 ? 32 : SMP_CACHE_BYTES) + static struct hwrng *current_rng; /* the current rng has been explicitly chosen by user via sysfs */ static int cur_rng_set_by_user; @@ -59,7 +62,7 @@ static inline int rng_get_data(struct hwrng *rng, u8 *buffer, size_t size, static size_t rng_buffer_size(void) { - return SMP_CACHE_BYTES < 32 ? 32 : SMP_CACHE_BYTES; + return RNG_BUFFER_SIZE; } static void add_early_randomness(struct hwrng *rng) @@ -206,6 +209,7 @@ static inline int rng_get_data(struct hwrng *rng, u8 *buffer, size_t size, static ssize_t rng_dev_read(struct file *filp, char __user *buf, size_t size, loff_t *offp) { + u8 buffer[RNG_BUFFER_SIZE]; ssize_t ret = 0; int err = 0; int bytes_read, len; @@ -233,34 +237,37 @@ static ssize_t rng_dev_read(struct file *filp, char __user *buf, if (bytes_read < 0) { err = bytes_read; goto out_unlock_reading; + } else if (bytes_read == 0 && + (filp->f_flags & O_NONBLOCK)) { + err = -EAGAIN; + goto out_unlock_reading; } + data_avail = bytes_read; } - if (!data_avail) { - if (filp->f_flags & O_NONBLOCK) { - err = -EAGAIN; - goto out_unlock_reading; - } - } else { - len = data_avail; + len = data_avail; + if (len) { if (len > size) len = size; data_avail -= len; - if (copy_to_user(buf + ret, rng_buffer + data_avail, - len)) { + memcpy(buffer, rng_buffer + data_avail, len); + } + mutex_unlock(&reading_mutex); + put_rng(rng); + + if (len) { + if (copy_to_user(buf + ret, buffer, len)) { err = -EFAULT; - goto out_unlock_reading; + goto out; } size -= len; ret += len; } - mutex_unlock(&reading_mutex); - put_rng(rng); if (need_resched()) schedule_timeout_interruptible(1); @@ -271,6 +278,7 @@ static ssize_t rng_dev_read(struct file *filp, char __user *buf, } } out: + memzero_explicit(buffer, sizeof(buffer)); return ret ? : err; out_unlock_reading: -- 2.17.1

2 1

[PATCH openEuler-22.03-LTS-SP2] hwrng: core - Fix page fault dead lock on mmap-ed hwrng
by Guo Mengqi 21 May '24

21 May '24

From: Herbert Xu <herbert(a)gondor.apana.org.au> stable inclusion from stable-v5.10.210 commit c6a8111aacbfe7a8a70f46cc0de8eed00561693c category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/I99JR3 CVE: CVE-2023-52615 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id… -------------------------------- commit 78aafb3884f6bc6636efcc1760c891c8500b9922 upstream. There is a dead-lock in the hwrng device read path. This triggers when the user reads from /dev/hwrng into memory also mmap-ed from /dev/hwrng. The resulting page fault triggers a recursive read which then dead-locks. Fix this by using a stack buffer when calling copy_to_user. Reported-by: Edward Adam Davis <eadavis(a)qq.com> Reported-by: syzbot+c52ab18308964d248092(a)syzkaller.appspotmail.com Fixes: 9996508b3353 ("hwrng: core - Replace u32 in driver API with byte array") Cc: <stable(a)vger.kernel.org> Signed-off-by: Herbert Xu <herbert(a)gondor.apana.org.au> Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org> Signed-off-by: Yi Yang <yiyang13(a)huawei.com> --- drivers/char/hw_random/core.c | 34 +++++++++++++++++++++------------- 1 file changed, 21 insertions(+), 13 deletions(-) diff --git a/drivers/char/hw_random/core.c b/drivers/char/hw_random/core.c index 5749998feaa4..6e2c1ba18012 100644 --- a/drivers/char/hw_random/core.c +++ b/drivers/char/hw_random/core.c @@ -24,10 +24,13 @@ #include <linux/random.h> #include <linux/sched.h> #include <linux/slab.h> +#include <linux/string.h> #include <linux/uaccess.h> #define RNG_MODULE_NAME "hw_random" +#define RNG_BUFFER_SIZE (SMP_CACHE_BYTES < 32 ? 32 : SMP_CACHE_BYTES) + static struct hwrng *current_rng; /* the current rng has been explicitly chosen by user via sysfs */ static int cur_rng_set_by_user; @@ -59,7 +62,7 @@ static inline int rng_get_data(struct hwrng *rng, u8 *buffer, size_t size, static size_t rng_buffer_size(void) { - return SMP_CACHE_BYTES < 32 ? 32 : SMP_CACHE_BYTES; + return RNG_BUFFER_SIZE; } static void add_early_randomness(struct hwrng *rng) @@ -206,6 +209,7 @@ static inline int rng_get_data(struct hwrng *rng, u8 *buffer, size_t size, static ssize_t rng_dev_read(struct file *filp, char __user *buf, size_t size, loff_t *offp) { + u8 buffer[RNG_BUFFER_SIZE]; ssize_t ret = 0; int err = 0; int bytes_read, len; @@ -233,34 +237,37 @@ static ssize_t rng_dev_read(struct file *filp, char __user *buf, if (bytes_read < 0) { err = bytes_read; goto out_unlock_reading; + } else if (bytes_read == 0 && + (filp->f_flags & O_NONBLOCK)) { + err = -EAGAIN; + goto out_unlock_reading; } + data_avail = bytes_read; } - if (!data_avail) { - if (filp->f_flags & O_NONBLOCK) { - err = -EAGAIN; - goto out_unlock_reading; - } - } else { - len = data_avail; + len = data_avail; + if (len) { if (len > size) len = size; data_avail -= len; - if (copy_to_user(buf + ret, rng_buffer + data_avail, - len)) { + memcpy(buffer, rng_buffer + data_avail, len); + } + mutex_unlock(&reading_mutex); + put_rng(rng); + + if (len) { + if (copy_to_user(buf + ret, buffer, len)) { err = -EFAULT; - goto out_unlock_reading; + goto out; } size -= len; ret += len; } - mutex_unlock(&reading_mutex); - put_rng(rng); if (need_resched()) schedule_timeout_interruptible(1); @@ -271,6 +278,7 @@ static ssize_t rng_dev_read(struct file *filp, char __user *buf, } } out: + memzero_explicit(buffer, sizeof(buffer)); return ret ? : err; out_unlock_reading: -- 2.17.1

2 1

[PATCH openEuler-22.03-LTS-SP1] hwrng: core - Fix page fault dead lock on mmap-ed hwrng
by Guo Mengqi 21 May '24

21 May '24

From: Herbert Xu <herbert(a)gondor.apana.org.au> stable inclusion from stable-v5.10.210 commit c6a8111aacbfe7a8a70f46cc0de8eed00561693c category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/I99JR3 CVE: CVE-2023-52615 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id… -------------------------------- commit 78aafb3884f6bc6636efcc1760c891c8500b9922 upstream. There is a dead-lock in the hwrng device read path. This triggers when the user reads from /dev/hwrng into memory also mmap-ed from /dev/hwrng. The resulting page fault triggers a recursive read which then dead-locks. Fix this by using a stack buffer when calling copy_to_user. Reported-by: Edward Adam Davis <eadavis(a)qq.com> Reported-by: syzbot+c52ab18308964d248092(a)syzkaller.appspotmail.com Fixes: 9996508b3353 ("hwrng: core - Replace u32 in driver API with byte array") Cc: <stable(a)vger.kernel.org> Signed-off-by: Herbert Xu <herbert(a)gondor.apana.org.au> Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org> Signed-off-by: Yi Yang <yiyang13(a)huawei.com> --- drivers/char/hw_random/core.c | 34 +++++++++++++++++++++------------- 1 file changed, 21 insertions(+), 13 deletions(-) diff --git a/drivers/char/hw_random/core.c b/drivers/char/hw_random/core.c index 5749998feaa4..6e2c1ba18012 100644 --- a/drivers/char/hw_random/core.c +++ b/drivers/char/hw_random/core.c @@ -24,10 +24,13 @@ #include <linux/random.h> #include <linux/sched.h> #include <linux/slab.h> +#include <linux/string.h> #include <linux/uaccess.h> #define RNG_MODULE_NAME "hw_random" +#define RNG_BUFFER_SIZE (SMP_CACHE_BYTES < 32 ? 32 : SMP_CACHE_BYTES) + static struct hwrng *current_rng; /* the current rng has been explicitly chosen by user via sysfs */ static int cur_rng_set_by_user; @@ -59,7 +62,7 @@ static inline int rng_get_data(struct hwrng *rng, u8 *buffer, size_t size, static size_t rng_buffer_size(void) { - return SMP_CACHE_BYTES < 32 ? 32 : SMP_CACHE_BYTES; + return RNG_BUFFER_SIZE; } static void add_early_randomness(struct hwrng *rng) @@ -206,6 +209,7 @@ static inline int rng_get_data(struct hwrng *rng, u8 *buffer, size_t size, static ssize_t rng_dev_read(struct file *filp, char __user *buf, size_t size, loff_t *offp) { + u8 buffer[RNG_BUFFER_SIZE]; ssize_t ret = 0; int err = 0; int bytes_read, len; @@ -233,34 +237,37 @@ static ssize_t rng_dev_read(struct file *filp, char __user *buf, if (bytes_read < 0) { err = bytes_read; goto out_unlock_reading; + } else if (bytes_read == 0 && + (filp->f_flags & O_NONBLOCK)) { + err = -EAGAIN; + goto out_unlock_reading; } + data_avail = bytes_read; } - if (!data_avail) { - if (filp->f_flags & O_NONBLOCK) { - err = -EAGAIN; - goto out_unlock_reading; - } - } else { - len = data_avail; + len = data_avail; + if (len) { if (len > size) len = size; data_avail -= len; - if (copy_to_user(buf + ret, rng_buffer + data_avail, - len)) { + memcpy(buffer, rng_buffer + data_avail, len); + } + mutex_unlock(&reading_mutex); + put_rng(rng); + + if (len) { + if (copy_to_user(buf + ret, buffer, len)) { err = -EFAULT; - goto out_unlock_reading; + goto out; } size -= len; ret += len; } - mutex_unlock(&reading_mutex); - put_rng(rng); if (need_resched()) schedule_timeout_interruptible(1); @@ -271,6 +278,7 @@ static ssize_t rng_dev_read(struct file *filp, char __user *buf, } } out: + memzero_explicit(buffer, sizeof(buffer)); return ret ? : err; out_unlock_reading: -- 2.17.1

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[PATCH openEuler-22.03-LTS] hwrng: core - Fix page fault dead lock on mmap-ed hwrng
by Guo Mengqi 21 May '24

21 May '24

From: Herbert Xu <herbert(a)gondor.apana.org.au> stable inclusion from stable-v5.10.210 commit c6a8111aacbfe7a8a70f46cc0de8eed00561693c category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/I99JR3 CVE: CVE-2023-52615 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id… -------------------------------- commit 78aafb3884f6bc6636efcc1760c891c8500b9922 upstream. There is a dead-lock in the hwrng device read path. This triggers when the user reads from /dev/hwrng into memory also mmap-ed from /dev/hwrng. The resulting page fault triggers a recursive read which then dead-locks. Fix this by using a stack buffer when calling copy_to_user. Reported-by: Edward Adam Davis <eadavis(a)qq.com> Reported-by: syzbot+c52ab18308964d248092(a)syzkaller.appspotmail.com Fixes: 9996508b3353 ("hwrng: core - Replace u32 in driver API with byte array") Cc: <stable(a)vger.kernel.org> Signed-off-by: Herbert Xu <herbert(a)gondor.apana.org.au> Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org> Signed-off-by: Yi Yang <yiyang13(a)huawei.com> --- drivers/char/hw_random/core.c | 34 +++++++++++++++++++++------------- 1 file changed, 21 insertions(+), 13 deletions(-) diff --git a/drivers/char/hw_random/core.c b/drivers/char/hw_random/core.c index 5749998feaa4..6e2c1ba18012 100644 --- a/drivers/char/hw_random/core.c +++ b/drivers/char/hw_random/core.c @@ -24,10 +24,13 @@ #include <linux/random.h> #include <linux/sched.h> #include <linux/slab.h> +#include <linux/string.h> #include <linux/uaccess.h> #define RNG_MODULE_NAME "hw_random" +#define RNG_BUFFER_SIZE (SMP_CACHE_BYTES < 32 ? 32 : SMP_CACHE_BYTES) + static struct hwrng *current_rng; /* the current rng has been explicitly chosen by user via sysfs */ static int cur_rng_set_by_user; @@ -59,7 +62,7 @@ static inline int rng_get_data(struct hwrng *rng, u8 *buffer, size_t size, static size_t rng_buffer_size(void) { - return SMP_CACHE_BYTES < 32 ? 32 : SMP_CACHE_BYTES; + return RNG_BUFFER_SIZE; } static void add_early_randomness(struct hwrng *rng) @@ -206,6 +209,7 @@ static inline int rng_get_data(struct hwrng *rng, u8 *buffer, size_t size, static ssize_t rng_dev_read(struct file *filp, char __user *buf, size_t size, loff_t *offp) { + u8 buffer[RNG_BUFFER_SIZE]; ssize_t ret = 0; int err = 0; int bytes_read, len; @@ -233,34 +237,37 @@ static ssize_t rng_dev_read(struct file *filp, char __user *buf, if (bytes_read < 0) { err = bytes_read; goto out_unlock_reading; + } else if (bytes_read == 0 && + (filp->f_flags & O_NONBLOCK)) { + err = -EAGAIN; + goto out_unlock_reading; } + data_avail = bytes_read; } - if (!data_avail) { - if (filp->f_flags & O_NONBLOCK) { - err = -EAGAIN; - goto out_unlock_reading; - } - } else { - len = data_avail; + len = data_avail; + if (len) { if (len > size) len = size; data_avail -= len; - if (copy_to_user(buf + ret, rng_buffer + data_avail, - len)) { + memcpy(buffer, rng_buffer + data_avail, len); + } + mutex_unlock(&reading_mutex); + put_rng(rng); + + if (len) { + if (copy_to_user(buf + ret, buffer, len)) { err = -EFAULT; - goto out_unlock_reading; + goto out; } size -= len; ret += len; } - mutex_unlock(&reading_mutex); - put_rng(rng); if (need_resched()) schedule_timeout_interruptible(1); @@ -271,6 +278,7 @@ static ssize_t rng_dev_read(struct file *filp, char __user *buf, } } out: + memzero_explicit(buffer, sizeof(buffer)); return ret ? : err; out_unlock_reading: -- 2.17.1

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