- Kernel - mailweb.openeuler.org

[PATCH openEuler-22.03-LTS-SP1] tracing: Prevent bad count for tracing_cpumask_write
by Luo Gengkun 07 Jan '25

07 Jan '25

From: Lizhi Xu <lizhi.xu(a)windriver.com> mainline inclusion from mainline-v6.13-rc5 commit 98feccbf32cfdde8c722bc4587aaa60ee5ac33f0 category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/IBG2PO CVE: CVE-2024-56763 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?… -------------------------------- If a large count is provided, it will trigger a warning in bitmap_parse_user. Also check zero for it. Cc: stable(a)vger.kernel.org Fixes: 9e01c1b74c953 ("cpumask: convert kernel trace functions") Link: https://lore.kernel.org/20241216073238.2573704-1-lizhi.xu@windriver.com Reported-by: syzbot+0aecfd34fb878546f3fd(a)syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=0aecfd34fb878546f3fd Tested-by: syzbot+0aecfd34fb878546f3fd(a)syzkaller.appspotmail.com Signed-off-by: Lizhi Xu <lizhi.xu(a)windriver.com> Signed-off-by: Steven Rostedt (Google) <rostedt(a)goodmis.org> Signed-off-by: Luo Gengkun <luogengkun2(a)huawei.com> --- kernel/trace/trace.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index e9a737451a76..fa138d1bba56 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -4878,6 +4878,9 @@ tracing_cpumask_write(struct file *filp, const char __user *ubuf, cpumask_var_t tracing_cpumask_new; int err; + if (count == 0 || count > KMALLOC_MAX_SIZE) + return -EINVAL; + if (!zalloc_cpumask_var(&tracing_cpumask_new, GFP_KERNEL)) return -ENOMEM; -- 2.34.1

2 1

[PATCH OLK-5.10] tracing: Prevent bad count for tracing_cpumask_write
by Luo Gengkun 07 Jan '25

07 Jan '25

From: Lizhi Xu <lizhi.xu(a)windriver.com> mainline inclusion from mainline-v6.13-rc5 commit 98feccbf32cfdde8c722bc4587aaa60ee5ac33f0 category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/IBG2PO CVE: CVE-2024-56763 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?… -------------------------------- If a large count is provided, it will trigger a warning in bitmap_parse_user. Also check zero for it. Cc: stable(a)vger.kernel.org Fixes: 9e01c1b74c953 ("cpumask: convert kernel trace functions") Link: https://lore.kernel.org/20241216073238.2573704-1-lizhi.xu@windriver.com Reported-by: syzbot+0aecfd34fb878546f3fd(a)syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=0aecfd34fb878546f3fd Tested-by: syzbot+0aecfd34fb878546f3fd(a)syzkaller.appspotmail.com Signed-off-by: Lizhi Xu <lizhi.xu(a)windriver.com> Signed-off-by: Steven Rostedt (Google) <rostedt(a)goodmis.org> Signed-off-by: Luo Gengkun <luogengkun2(a)huawei.com> --- kernel/trace/trace.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index a470950b8ed6..462d2a70a835 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -4869,6 +4869,9 @@ tracing_cpumask_write(struct file *filp, const char __user *ubuf, cpumask_var_t tracing_cpumask_new; int err; + if (count == 0 || count > KMALLOC_MAX_SIZE) + return -EINVAL; + if (!zalloc_cpumask_var(&tracing_cpumask_new, GFP_KERNEL)) return -ENOMEM; -- 2.34.1

2 1

[PATCH OLK-6.6] tracing: Prevent bad count for tracing_cpumask_write
by Luo Gengkun 07 Jan '25

07 Jan '25

From: Lizhi Xu <lizhi.xu(a)windriver.com> stable inclusion from stable-v6.6.69 commit 03041e474a6a8f1bfd4b96b164bb3165c48fa1a3 category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/IBG2PO CVE: CVE-2024-56763 Reference: https://git.kernel.org/stable/c/03041e474a6a8f1bfd4b96b164bb3165c48fa1a3 -------------------------------- commit 98feccbf32cfdde8c722bc4587aaa60ee5ac33f0 upstream. If a large count is provided, it will trigger a warning in bitmap_parse_user. Also check zero for it. Cc: stable(a)vger.kernel.org Fixes: 9e01c1b74c953 ("cpumask: convert kernel trace functions") Link: https://lore.kernel.org/20241216073238.2573704-1-lizhi.xu@windriver.com Reported-by: syzbot+0aecfd34fb878546f3fd(a)syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=0aecfd34fb878546f3fd Tested-by: syzbot+0aecfd34fb878546f3fd(a)syzkaller.appspotmail.com Signed-off-by: Lizhi Xu <lizhi.xu(a)windriver.com> Signed-off-by: Steven Rostedt (Google) <rostedt(a)goodmis.org> Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org> Signed-off-by: Luo Gengkun <luogengkun2(a)huawei.com> --- kernel/trace/trace.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index 02bc8e03ffa1..24c995d1dab2 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -5331,6 +5331,9 @@ tracing_cpumask_write(struct file *filp, const char __user *ubuf, cpumask_var_t tracing_cpumask_new; int err; + if (count == 0 || count > KMALLOC_MAX_SIZE) + return -EINVAL; + if (!zalloc_cpumask_var(&tracing_cpumask_new, GFP_KERNEL)) return -ENOMEM; -- 2.34.1

2 1

[PATCH openEuler-22.03-LTS-SP1 0/1] CVE-2024-56567
by Liao Chen 07 Jan '25

07 Jan '25

fix CVE-2024-56567 Zicheng Qu (1): ad7780: fix division by zero in ad7780_write_raw() drivers/iio/adc/ad7780.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) -- 2.34.1

2 2

[openeuler:OLK-5.10 2656/2656] kernel/rcu/update.o: warning: objtool: synchronize_rcu_tasks_trace()+0xde: unreachable instruction
by kernel test robot 07 Jan '25

07 Jan '25

tree: https://gitee.com/openeuler/kernel.git OLK-5.10 head: 9be6ae394c896999214be0f875765d2c58d15b13 commit: 2509f2079e7247ed0d695bdb69c3d019a700a4b8 [2656/2656] rcu-tasks: Make rude RCU-Tasks work well with CPU hotplug config: x86_64-buildonly-randconfig-006-20250107 (https://download.01.org/0day-ci/archive/20250107/202501071757.EREnWTHH-lkp@…) compiler: clang version 19.1.3 (https://github.com/llvm/llvm-project ab51eccf88f5321e7c60591c5546b254b6afab99) reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20250107/202501071757.EREnWTHH-lkp@…) If you fix the issue in a separate patch/commit (i.e. not just a new version of the same patch/commit), kindly add following tags | Reported-by: kernel test robot <lkp(a)intel.com> | Closes: https://lore.kernel.org/oe-kbuild-all/202501071757.EREnWTHH-lkp@intel.com/ All warnings (new ones prefixed by >>): >> kernel/rcu/update.o: warning: objtool: synchronize_rcu_tasks_trace()+0xde: unreachable instruction -- 0-DAY CI Kernel Test Service https://github.com/intel/lkp-tests/wiki

1 0

[PATCH openEuler-1.0-LTS 0/3] CVE-2024-56642
by Liu Jian 07 Jan '25

07 Jan '25

CVE-2024-56642 Eric Dumazet (1): tipc: fix NULL deref in cleanup_bearer() Kuniyuki Iwashima (1): tipc: Fix use-after-free of kernel socket in cleanup_bearer(). Xin Long (1): tipc: remove ub->ubsock checks net/tipc/udp_media.c | 19 +++++++++++-------- 1 file changed, 11 insertions(+), 8 deletions(-) -- 2.34.1

2 4

[PATCH OLK-6.6] bpf, sockmap: Several fixes to bpf_msg_pop_data
by Liu Jian 07 Jan '25

07 Jan '25

From: Zijian Zhang <zijianzhang(a)bytedance.com> stable inclusion from stable-v6.6.64 commit 98c7ea7d11f2588e8197db042e0291e4ac8f8346 category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/IBEGFC CVE: CVE-2024-56720 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id… ------------------------------------------------- [ Upstream commit 5d609ba262475db450ba69b8e8a557bd768ac07a ] Several fixes to bpf_msg_pop_data, 1. In sk_msg_shift_left, we should put_page 2. if (len == 0), return early is better 3. pop the entire sk_msg (last == msg->sg.size) should be supported 4. Fix for the value of variable "a" 5. In sk_msg_shift_left, after shifting, i has already pointed to the next element. Addtional sk_msg_iter_var_next may result in BUG. Fixes: 7246d8ed4dcc ("bpf: helper to pop data from messages") Signed-off-by: Zijian Zhang <zijianzhang(a)bytedance.com> Reviewed-by: John Fastabend <john.fastabend(a)gmail.com> Link: https://lore.kernel.org/r/20241106222520.527076-8-zijianzhang@bytedance.com Signed-off-by: Martin KaFai Lau <martin.lau(a)kernel.org> Signed-off-by: Sasha Levin <sashal(a)kernel.org> Signed-off-by: Liu Jian <liujian56(a)huawei.com> --- net/core/filter.c | 15 +++++++++------ 1 file changed, 9 insertions(+), 6 deletions(-) diff --git a/net/core/filter.c b/net/core/filter.c index 48dd2896ee1d9..131a21b5463cc 100644 --- a/net/core/filter.c +++ b/net/core/filter.c @@ -2889,8 +2889,10 @@ static const struct bpf_func_proto bpf_msg_push_data_proto = { static void sk_msg_shift_left(struct sk_msg *msg, int i) { + struct scatterlist *sge = sk_msg_elem(msg, i); int prev; + put_page(sg_page(sge)); do { prev = i; sk_msg_iter_var_next(i); @@ -2927,6 +2929,9 @@ BPF_CALL_4(bpf_msg_pop_data, struct sk_msg *, msg, u32, start, if (unlikely(flags)) return -EINVAL; + if (unlikely(len == 0)) + return 0; + /* First find the starting scatterlist element */ i = msg->sg.start; do { @@ -2939,7 +2944,7 @@ BPF_CALL_4(bpf_msg_pop_data, struct sk_msg *, msg, u32, start, } while (i != msg->sg.end); /* Bounds checks: start and pop must be inside message */ - if (start >= offset + l || last >= msg->sg.size) + if (start >= offset + l || last > msg->sg.size) return -EINVAL; space = MAX_MSG_FRAGS - sk_msg_elem_used(msg); @@ -2968,12 +2973,12 @@ BPF_CALL_4(bpf_msg_pop_data, struct sk_msg *, msg, u32, start, */ if (start != offset) { struct scatterlist *nsge, *sge = sk_msg_elem(msg, i); - int a = start; + int a = start - offset; int b = sge->length - pop - a; sk_msg_iter_var_next(i); - if (pop < sge->length - a) { + if (b > 0) { if (space) { sge->length = a; sk_msg_shift_right(msg, i); @@ -2992,7 +2997,6 @@ BPF_CALL_4(bpf_msg_pop_data, struct sk_msg *, msg, u32, start, if (unlikely(!page)) return -ENOMEM; - sge->length = a; orig = sg_page(sge); from = sg_virt(sge); to = page_address(page); @@ -3002,7 +3006,7 @@ BPF_CALL_4(bpf_msg_pop_data, struct sk_msg *, msg, u32, start, put_page(orig); } pop = 0; - } else if (pop >= sge->length - a) { + } else { pop -= (sge->length - a); sge->length = a; } @@ -3036,7 +3040,6 @@ BPF_CALL_4(bpf_msg_pop_data, struct sk_msg *, msg, u32, start, pop -= sge->length; sk_msg_shift_left(msg, i); } - sk_msg_iter_var_next(i); } sk_mem_uncharge(msg->sk, len - pop); -- 2.34.1

2 5

[PATCH OLK-5.10] tcp_bpf: Fix the sk_mem_uncharge logic in tcp_bpf_sendmsg
by Liu Jian 07 Jan '25

07 Jan '25

From: Zijian Zhang <zijianzhang(a)bytedance.com> stable inclusion from stable-v5.10.231 commit dbedc7e142df5ea238a46fdd7462c1c42cd36a10 category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/IBEANQ CVE: CVE-2024-56633 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id… ------------------------------------------------- [ Upstream commit ca70b8baf2bd125b2a4d96e76db79375c07d7ff2 ] The current sk memory accounting logic in __SK_REDIRECT is pre-uncharging tosend bytes, which is either msg->sg.size or a smaller value apply_bytes. Potential problems with this strategy are as follows: - If the actual sent bytes are smaller than tosend, we need to charge some bytes back, as in line 487, which is okay but seems not clean. - When tosend is set to apply_bytes, as in line 417, and (ret < 0), we may miss uncharging (msg->sg.size - apply_bytes) bytes. [...] 415 tosend = msg->sg.size; 416 if (psock->apply_bytes && psock->apply_bytes < tosend) 417 tosend = psock->apply_bytes; [...] 443 sk_msg_return(sk, msg, tosend); 444 release_sock(sk); 446 origsize = msg->sg.size; 447 ret = tcp_bpf_sendmsg_redir(sk_redir, redir_ingress, 448 msg, tosend, flags); 449 sent = origsize - msg->sg.size; [...] 454 lock_sock(sk); 455 if (unlikely(ret < 0)) { 456 int free = sk_msg_free_nocharge(sk, msg); 458 if (!cork) 459 *copied -= free; 460 } [...] 487 if (eval == __SK_REDIRECT) 488 sk_mem_charge(sk, tosend - sent); [...] When running the selftest test_txmsg_redir_wait_sndmem with txmsg_apply, the following warning will be reported: ------------[ cut here ]------------ WARNING: CPU: 6 PID: 57 at net/ipv4/af_inet.c:156 inet_sock_destruct+0x190/0x1a0 Modules linked in: CPU: 6 UID: 0 PID: 57 Comm: kworker/6:0 Not tainted 6.12.0-rc1.bm.1-amd64+ #43 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-1 04/01/2014 Workqueue: events sk_psock_destroy RIP: 0010:inet_sock_destruct+0x190/0x1a0 RSP: 0018:ffffad0a8021fe08 EFLAGS: 00010206 RAX: 0000000000000011 RBX: ffff9aab4475b900 RCX: ffff9aab481a0800 RDX: 0000000000000303 RSI: 0000000000000011 RDI: ffff9aab4475b900 RBP: ffff9aab4475b990 R08: 0000000000000000 R09: ffff9aab40050ec0 R10: 0000000000000000 R11: ffff9aae6fdb1d01 R12: ffff9aab49c60400 R13: ffff9aab49c60598 R14: ffff9aab49c60598 R15: dead000000000100 FS: 0000000000000000(0000) GS:ffff9aae6fd80000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ffec7e47bd8 CR3: 00000001a1a1c004 CR4: 0000000000770ef0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 PKRU: 55555554 Call Trace: <TASK> ? __warn+0x89/0x130 ? inet_sock_destruct+0x190/0x1a0 ? report_bug+0xfc/0x1e0 ? handle_bug+0x5c/0xa0 ? exc_invalid_op+0x17/0x70 ? asm_exc_invalid_op+0x1a/0x20 ? inet_sock_destruct+0x190/0x1a0 __sk_destruct+0x25/0x220 sk_psock_destroy+0x2b2/0x310 process_scheduled_works+0xa3/0x3e0 worker_thread+0x117/0x240 ? __pfx_worker_thread+0x10/0x10 kthread+0xcf/0x100 ? __pfx_kthread+0x10/0x10 ret_from_fork+0x31/0x40 ? __pfx_kthread+0x10/0x10 ret_from_fork_asm+0x1a/0x30 </TASK> ---[ end trace 0000000000000000 ]--- In __SK_REDIRECT, a more concise way is delaying the uncharging after sent bytes are finalized, and uncharge this value. When (ret < 0), we shall invoke sk_msg_free. Same thing happens in case __SK_DROP, when tosend is set to apply_bytes, we may miss uncharging (msg->sg.size - apply_bytes) bytes. The same warning will be reported in selftest. [...] 468 case __SK_DROP: 469 default: 470 sk_msg_free_partial(sk, msg, tosend); 471 sk_msg_apply_bytes(psock, tosend); 472 *copied -= (tosend + delta); 473 return -EACCES; [...] So instead of sk_msg_free_partial we can do sk_msg_free here. Fixes: 604326b41a6f ("bpf, sockmap: convert to generic sk_msg interface") Fixes: 8ec95b94716a ("bpf, sockmap: Fix the sk->sk_forward_alloc warning of sk_stream_kill_queues") Signed-off-by: Zijian Zhang <zijianzhang(a)bytedance.com> Signed-off-by: Daniel Borkmann <daniel(a)iogearbox.net> Acked-by: John Fastabend <john.fastabend(a)gmail.com> Link: https://lore.kernel.org/bpf/20241016234838.3167769-3-zijianzhang@bytedance.… Signed-off-by: Sasha Levin <sashal(a)kernel.org> Signed-off-by: Liu Jian <liujian56(a)huawei.com> --- net/ipv4/tcp_bpf.c | 11 ++++------- 1 file changed, 4 insertions(+), 7 deletions(-) diff --git a/net/ipv4/tcp_bpf.c b/net/ipv4/tcp_bpf.c index 8645017da9df9..384121426ea28 100644 --- a/net/ipv4/tcp_bpf.c +++ b/net/ipv4/tcp_bpf.c @@ -447,7 +447,6 @@ static int tcp_bpf_send_verdict(struct sock *sk, struct sk_psock *psock, cork = true; psock->cork = NULL; } - sk_msg_return(sk, msg, tosend); release_sock(sk); origsize = msg->sg.size; @@ -459,8 +458,9 @@ static int tcp_bpf_send_verdict(struct sock *sk, struct sk_psock *psock, sock_put(sk_redir); lock_sock(sk); + sk_mem_uncharge(sk, sent); if (unlikely(ret < 0)) { - int free = sk_msg_free_nocharge(sk, msg); + int free = sk_msg_free(sk, msg); if (!cork) *copied -= free; @@ -474,7 +474,7 @@ static int tcp_bpf_send_verdict(struct sock *sk, struct sk_psock *psock, break; case __SK_DROP: default: - sk_msg_free_partial(sk, msg, tosend); + sk_msg_free(sk, msg); sk_msg_apply_bytes(psock, tosend); *copied -= (tosend + delta); return -EACCES; @@ -490,11 +490,8 @@ static int tcp_bpf_send_verdict(struct sock *sk, struct sk_psock *psock, } if (msg && msg->sg.data[msg->sg.start].page_link && - msg->sg.data[msg->sg.start].length) { - if (eval == __SK_REDIRECT) - sk_mem_charge(sk, tosend - sent); + msg->sg.data[msg->sg.start].length) goto more_data; - } } return ret; } -- 2.34.1

2 1

[PATCH OLK-6.6] drm/i915/hdcp: Add encoder check in hdcp2_get_capability
by He Yujie 07 Jan '25

07 Jan '25

From: Suraj Kandpal <suraj.kandpal(a)intel.com> mainline inclusion from mainline-v6.12-rc1 commit d34f4f058edf1235c103ca9c921dc54820d14d40 category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/IB5KQZ CVE: CVE-2024-53050 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?… -------------------------------- Add encoder check in intel_hdcp2_get_capability to avoid null pointer error. Signed-off-by: Suraj Kandpal <suraj.kandpal(a)intel.com> Reviewed-by: Dnyaneshwar Bhadane <dnyaneshwar.bhadane(a)intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20240722064451.3610512-3-sura… Conflicts: drivers/gpu/drm/i915/display/intel_hdcp.c drivers/gpu/drm/i915/display/intel_dp_hdcp.c [ Context conflict: 130849f8ec14("drm/i915/hdcp: Use intel_connector as argument for hdcp_2_2_capable") a35239a89259("drm/i915/hdcp: Use correct aux for capability check scenario") 287c0de8b294("drm/i915/hdcp: Move to direct reads for HDCP") 55d9b2b8e440("drm/i915/hdcp: Refactor intel_dp_hdcp2_capable") 8e754d9e9e8a("drm/i915/hdcp: Rename hdcp capable functions") the above patches are not merge. ] Signed-off-by: He Yujie <coka.heyujie(a)huawei.com> --- drivers/gpu/drm/i915/display/intel_hdcp.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/i915/display/intel_hdcp.c b/drivers/gpu/drm/i915/display/intel_hdcp.c index cb99839afcd0..762170e6cbbb 100644 --- a/drivers/gpu/drm/i915/display/intel_hdcp.c +++ b/drivers/gpu/drm/i915/display/intel_hdcp.c @@ -163,7 +163,7 @@ bool intel_hdcp_capable(struct intel_connector *connector) /* Is HDCP2.2 capable on Platform and Sink */ bool intel_hdcp2_capable(struct intel_connector *connector) { - struct intel_digital_port *dig_port = intel_attached_dig_port(connector); + struct intel_digital_port *dig_port; struct drm_i915_private *i915 = to_i915(connector->base.dev); struct intel_hdcp *hdcp = &connector->hdcp; bool capable = false; @@ -192,6 +192,11 @@ bool intel_hdcp2_capable(struct intel_connector *connector) } mutex_unlock(&i915->display.hdcp.hdcp_mutex); + if (!intel_attached_encoder(connector)) + return false; + + dig_port = intel_attached_dig_port(connector); + /* Sink's capability for HDCP2.2 */ hdcp->shim->hdcp_2_2_capable(dig_port, &capable); -- 2.34.1

2 1

[PATCH OLK-6.6] nilfs2: fix null-ptr-deref in block_touch_buffer tracepoint
by He Yujie 07 Jan '25

07 Jan '25

From: Ryusuke Konishi <konishi.ryusuke(a)gmail.com> stable inclusion from stable-v6.6.63 commit 59b49ca67cca7b007a5afd3de0283c8008157665 category: bugfix bugzilla: https://gitee.com/openeuler/kernel/issues/IBA6RL CVE: CVE-2024-53131 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id… -------------------------------- commit cd45e963e44b0f10d90b9e6c0e8b4f47f3c92471 upstream. Patch series "nilfs2: fix null-ptr-deref bugs on block tracepoints". This series fixes null pointer dereference bugs that occur when using nilfs2 and two block-related tracepoints. This patch (of 2): It has been reported that when using "block:block_touch_buffer" tracepoint, touch_buffer() called from __nilfs_get_folio_block() causes a NULL pointer dereference, or a general protection fault when KASAN is enabled. This happens because since the tracepoint was added in touch_buffer(), it references the dev_t member bh->b_bdev->bd_dev regardless of whether the buffer head has a pointer to a block_device structure. In the current implementation, the block_device structure is set after the function returns to the caller. Here, touch_buffer() is used to mark the folio/page that owns the buffer head as accessed, but the common search helper for folio/page used by the caller function was optimized to mark the folio/page as accessed when it was reimplemented a long time ago, eliminating the need to call touch_buffer() here in the first place. So this solves the issue by eliminating the touch_buffer() call itself. Link: https://lkml.kernel.org/r/20241106160811.3316-1-konishi.ryusuke@gmail.com Link: https://lkml.kernel.org/r/20241106160811.3316-2-konishi.ryusuke@gmail.com Fixes: 5305cb830834 ("block: add block_{touch|dirty}_buffer tracepoint") Signed-off-by: Ryusuke Konishi <konishi.ryusuke(a)gmail.com> Reported-by: Ubisectech Sirius <bugreport(a)valiantsec.com> Closes: https://lkml.kernel.org/r/86bd3013-887e-4e38-960f-ca45c657f032.bugreport@va… Reported-by: syzbot+9982fb8d18eba905abe2(a)syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=9982fb8d18eba905abe2 Tested-by: syzbot+9982fb8d18eba905abe2(a)syzkaller.appspotmail.com Cc: Tejun Heo <tj(a)kernel.org> Cc: <stable(a)vger.kernel.org> Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org> Signed-off-by: He Yujie <coka.heyujie(a)huawei.com> --- fs/nilfs2/page.c | 1 - 1 file changed, 1 deletion(-) diff --git a/fs/nilfs2/page.c b/fs/nilfs2/page.c index 9bced0a5c253..144e200c4909 100644 --- a/fs/nilfs2/page.c +++ b/fs/nilfs2/page.c @@ -39,7 +39,6 @@ __nilfs_get_page_block(struct page *page, unsigned long block, pgoff_t index, first_block = (unsigned long)index << (PAGE_SHIFT - blkbits); bh = nilfs_page_get_nth_block(page, block - first_block); - touch_buffer(bh); wait_on_buffer(bh); return bh; } -- 2.34.1

2 1