stable inclusion from stable-v6.6.13 commit d9a6029ddee5e792379a604f5c72cc8b632d9944 category: bugfix bugzilla: https://gitee.com/openeuler/kernel/issues/I9A20H CVE: NA Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=... -------------------------------- [ Upstream commit 1cc111b9cddc71ce161cd388f11f0e9048edffdb ] KASAN report following issue. The root cause is when opening 'hist' file of an instance and accessing 'trace_event_file' in hist_show(), but 'trace_event_file' has been freed due to the instance being removed. 'hist_debug' file has the same problem. To fix it, call tracing_{open,release}_file_tr() in file_operations callback to have the ref count and avoid 'trace_event_file' being freed. BUG: KASAN: slab-use-after-free in hist_show+0x11e0/0x1278 Read of size 8 at addr ffff242541e336b8 by task head/190 CPU: 4 PID: 190 Comm: head Not tainted 6.7.0-rc5-g26aff849438c #133 Hardware name: linux,dummy-virt (DT) Call trace: dump_backtrace+0x98/0xf8 show_stack+0x1c/0x30 dump_stack_lvl+0x44/0x58 print_report+0xf0/0x5a0 kasan_report+0x80/0xc0 __asan_report_load8_noabort+0x1c/0x28 hist_show+0x11e0/0x1278 seq_read_iter+0x344/0xd78 seq_read+0x128/0x1c0 vfs_read+0x198/0x6c8 ksys_read+0xf4/0x1e0 __arm64_sys_read+0x70/0xa8 invoke_syscall+0x70/0x260 el0_svc_common.constprop.0+0xb0/0x280 do_el0_svc+0x44/0x60 el0_svc+0x34/0x68 el0t_64_sync_handler+0xb8/0xc0 el0t_64_sync+0x168/0x170 Allocated by task 188: kasan_save_stack+0x28/0x50 kasan_set_track+0x28/0x38 kasan_save_alloc_info+0x20/0x30 __kasan_slab_alloc+0x6c/0x80 kmem_cache_alloc+0x15c/0x4a8 trace_create_new_event+0x84/0x348 __trace_add_new_event+0x18/0x88 event_trace_add_tracer+0xc4/0x1a0 trace_array_create_dir+0x6c/0x100 trace_array_create+0x2e8/0x568 instance_mkdir+0x48/0x80 tracefs_syscall_mkdir+0x90/0xe8 vfs_mkdir+0x3c4/0x610 do_mkdirat+0x144/0x200 __arm64_sys_mkdirat+0x8c/0xc0 invoke_syscall+0x70/0x260 el0_svc_common.constprop.0+0xb0/0x280 do_el0_svc+0x44/0x60 el0_svc+0x34/0x68 el0t_64_sync_handler+0xb8/0xc0 el0t_64_sync+0x168/0x170 Freed by task 191: kasan_save_stack+0x28/0x50 kasan_set_track+0x28/0x38 kasan_save_free_info+0x34/0x58 __kasan_slab_free+0xe4/0x158 kmem_cache_free+0x19c/0x508 event_file_put+0xa0/0x120 remove_event_file_dir+0x180/0x320 event_trace_del_tracer+0xb0/0x180 __remove_instance+0x224/0x508 instance_rmdir+0x44/0x78 tracefs_syscall_rmdir+0xbc/0x140 vfs_rmdir+0x1cc/0x4c8 do_rmdir+0x220/0x2b8 __arm64_sys_unlinkat+0xc0/0x100 invoke_syscall+0x70/0x260 el0_svc_common.constprop.0+0xb0/0x280 do_el0_svc+0x44/0x60 el0_svc+0x34/0x68 el0t_64_sync_handler+0xb8/0xc0 el0t_64_sync+0x168/0x170 Link: https://lore.kernel.org/linux-trace-kernel/20231214012153.676155-1-zhengyeji... Suggested-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Zheng Yejian <zhengyejian1@huawei.com> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Zheng Yejian <zhengyejian1@huawei.com> --- kernel/trace/trace.c | 6 ++++++ kernel/trace/trace.h | 1 + kernel/trace/trace_events_hist.c | 12 ++++++++---- 3 files changed, 15 insertions(+), 4 deletions(-) diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index 310cfaa9c0f1..85b5bd03c977 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -4972,6 +4972,12 @@ int tracing_release_file_tr(struct inode *inode, struct file *filp) return 0; } +int tracing_single_release_file_tr(struct inode *inode, struct file *filp) +{ + tracing_release_file_tr(inode, filp); + return single_release(inode, filp); +} + static int tracing_mark_open(struct inode *inode, struct file *filp) { stream_open(inode, filp); diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h index 8eebd99cbb89..80f011207359 100644 --- a/kernel/trace/trace.h +++ b/kernel/trace/trace.h @@ -616,6 +616,7 @@ int tracing_open_generic(struct inode *inode, struct file *filp); int tracing_open_generic_tr(struct inode *inode, struct file *filp); int tracing_open_file_tr(struct inode *inode, struct file *filp); int tracing_release_file_tr(struct inode *inode, struct file *filp); +int tracing_single_release_file_tr(struct inode *inode, struct file *filp); bool tracing_is_disabled(void); bool tracer_tracing_is_on(struct trace_array *tr); void tracer_tracing_on(struct trace_array *tr); diff --git a/kernel/trace/trace_events_hist.c b/kernel/trace/trace_events_hist.c index d06938ae0717..68aaf0bd7a78 100644 --- a/kernel/trace/trace_events_hist.c +++ b/kernel/trace/trace_events_hist.c @@ -5630,10 +5630,12 @@ static int event_hist_open(struct inode *inode, struct file *file) { int ret; - ret = security_locked_down(LOCKDOWN_TRACEFS); + ret = tracing_open_file_tr(inode, file); if (ret) return ret; + /* Clear private_data to avoid warning in single_open() */ + file->private_data = NULL; return single_open(file, hist_show, file); } @@ -5641,7 +5643,7 @@ const struct file_operations event_hist_fops = { .open = event_hist_open, .read = seq_read, .llseek = seq_lseek, - .release = single_release, + .release = tracing_single_release_file_tr, }; #ifdef CONFIG_HIST_TRIGGERS_DEBUG @@ -5907,10 +5909,12 @@ static int event_hist_debug_open(struct inode *inode, struct file *file) { int ret; - ret = security_locked_down(LOCKDOWN_TRACEFS); + ret = tracing_open_file_tr(inode, file); if (ret) return ret; + /* Clear private_data to avoid warning in single_open() */ + file->private_data = NULL; return single_open(file, hist_debug_show, file); } @@ -5918,7 +5922,7 @@ const struct file_operations event_hist_debug_fops = { .open = event_hist_debug_open, .read = seq_read, .llseek = seq_lseek, - .release = single_release, + .release = tracing_single_release_file_tr, }; #endif -- 2.25.1