user/sven/linux.git/kernel/trace, branch v5.16.13

tracing: Fix return value of __setup handlers

2022-03-08T18:14:18Z

commit 1d02b444b8d1345ea4708db3bab4db89a7784b55 upstream. __setup() handlers should generally return 1 to indicate that the boot options have been handled. Using invalid option values causes the entire kernel boot option string to be reported as Unknown and added to init's environment strings, polluting it. Unknown kernel command line parameters "BOOT_IMAGE=/boot/bzImage-517rc6 kprobe_event=p,syscall_any,$arg1 trace_options=quiet trace_clock=jiffies", will be passed to user space. Run /sbin/init as init process with arguments: /sbin/init with environment: HOME=/ TERM=linux BOOT_IMAGE=/boot/bzImage-517rc6 kprobe_event=p,syscall_any,$arg1 trace_options=quiet trace_clock=jiffies Return 1 from the __setup() handlers so that init's environment is not polluted with kernel boot options. Link: lore.kernel.org/r/64644a2f-4a20-bab3-1e15-3b2cdd0defe3@omprussia.ru Link: https://lkml.kernel.org/r/20220303031744.32356-1-rdunlap@infradead.org Cc: stable@vger.kernel.org Fixes: 7bcfaf54f591 ("tracing: Add trace_options kernel command line parameter") Fixes: e1e232ca6b8f ("tracing: Add trace_clock= kernel parameter") Fixes: 970988e19eb0 ("tracing/kprobe: Add kprobe_event= boot parameter") Signed-off-by: Randy Dunlap Reported-by: Igor Zhbanov Acked-by: Masami Hiramatsu Signed-off-by: Steven Rostedt (Google) Signed-off-by: Greg Kroah-Hartman

tracing/histogram: Fix sorting on old "cpu" value

2022-03-08T18:14:18Z

commit 1d1898f65616c4601208963c3376c1d828cbf2c7 upstream. When trying to add a histogram against an event with the "cpu" field, it was impossible due to "cpu" being a keyword to key off of the running CPU. So to fix this, it was changed to "common_cpu" to match the other generic fields (like "common_pid"). But since some scripts used "cpu" for keying off of the CPU (for events that did not have "cpu" as a field, which is most of them), a backward compatibility trick was added such that if "cpu" was used as a key, and the event did not have "cpu" as a field name, then it would fallback and switch over to "common_cpu". This fix has a couple of subtle bugs. One was that when switching over to "common_cpu", it did not change the field name, it just set a flag. But the code still found a "cpu" field. The "cpu" field is used for filtering and is returned when the event does not have a "cpu" field. This was found by: # cd /sys/kernel/tracing # echo hist:key=cpu,pid:sort=cpu > events/sched/sched_wakeup/trigger # cat events/sched/sched_wakeup/hist Which showed the histogram unsorted: { cpu: 19, pid: 1175 } hitcount: 1 { cpu: 6, pid: 239 } hitcount: 2 { cpu: 23, pid: 1186 } hitcount: 14 { cpu: 12, pid: 249 } hitcount: 2 { cpu: 3, pid: 994 } hitcount: 5 Instead of hard coding the "cpu" checks, take advantage of the fact that trace_event_field_field() returns a special field for "cpu" and "CPU" if the event does not have "cpu" as a field. This special field has the "filter_type" of "FILTER_CPU". Check that to test if the returned field is of the CPU type instead of doing the string compare. Also, fix the sorting bug by testing for the hist_field flag of HIST_FIELD_FL_CPU when setting up the sort routine. Otherwise it will use the special CPU field to know what compare routine to use, and since that special field does not have a size, it returns tracing_map_cmp_none. Cc: stable@vger.kernel.org Fixes: 1e3bac71c505 ("tracing/histogram: Rename "cpu" to "common_cpu"") Reported-by: Daniel Bristot de Oliveira Signed-off-by: Steven Rostedt (Google) Signed-off-by: Greg Kroah-Hartman

blktrace: fix use after free for struct blk_trace

2022-03-08T18:14:07Z

commit 30939293262eb433c960c4532a0d59c4073b2b84 upstream. When tracing the whole disk, 'dropped' and 'msg' will be created under 'q->debugfs_dir' and 'bt->dir' is NULL, thus blk_trace_free() won't remove those files. What's worse, the following UAF can be triggered because of accessing stale 'dropped' and 'msg': ================================================================== BUG: KASAN: use-after-free in blk_dropped_read+0x89/0x100 Read of size 4 at addr ffff88816912f3d8 by task blktrace/1188 CPU: 27 PID: 1188 Comm: blktrace Not tainted 5.17.0-rc4-next-20220217+ #469 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS ?-20190727_073836-4 Call Trace: dump_stack_lvl+0x34/0x44 print_address_description.constprop.0.cold+0xab/0x381 ? blk_dropped_read+0x89/0x100 ? blk_dropped_read+0x89/0x100 kasan_report.cold+0x83/0xdf ? blk_dropped_read+0x89/0x100 kasan_check_range+0x140/0x1b0 blk_dropped_read+0x89/0x100 ? blk_create_buf_file_callback+0x20/0x20 ? kmem_cache_free+0xa1/0x500 ? do_sys_openat2+0x258/0x460 full_proxy_read+0x8f/0xc0 vfs_read+0xc6/0x260 ksys_read+0xb9/0x150 ? vfs_write+0x3d0/0x3d0 ? fpregs_assert_state_consistent+0x55/0x60 ? exit_to_user_mode_prepare+0x39/0x1e0 do_syscall_64+0x35/0x80 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7fbc080d92fd Code: ce 20 00 00 75 10 b8 00 00 00 00 0f 05 48 3d 01 f0 ff ff 73 31 c3 48 83 1 RSP: 002b:00007fbb95ff9cb0 EFLAGS: 00000293 ORIG_RAX: 0000000000000000 RAX: ffffffffffffffda RBX: 00007fbb95ff9dc0 RCX: 00007fbc080d92fd RDX: 0000000000000100 RSI: 00007fbb95ff9cc0 RDI: 0000000000000045 RBP: 0000000000000045 R08: 0000000000406299 R09: 00000000fffffffd R10: 000000000153afa0 R11: 0000000000000293 R12: 00007fbb780008c0 R13: 00007fbb78000938 R14: 0000000000608b30 R15: 00007fbb780029c8 Allocated by task 1050: kasan_save_stack+0x1e/0x40 __kasan_kmalloc+0x81/0xa0 do_blk_trace_setup+0xcb/0x410 __blk_trace_setup+0xac/0x130 blk_trace_ioctl+0xe9/0x1c0 blkdev_ioctl+0xf1/0x390 __x64_sys_ioctl+0xa5/0xe0 do_syscall_64+0x35/0x80 entry_SYSCALL_64_after_hwframe+0x44/0xae Freed by task 1050: kasan_save_stack+0x1e/0x40 kasan_set_track+0x21/0x30 kasan_set_free_info+0x20/0x30 __kasan_slab_free+0x103/0x180 kfree+0x9a/0x4c0 __blk_trace_remove+0x53/0x70 blk_trace_ioctl+0x199/0x1c0 blkdev_common_ioctl+0x5e9/0xb30 blkdev_ioctl+0x1a5/0x390 __x64_sys_ioctl+0xa5/0xe0 do_syscall_64+0x35/0x80 entry_SYSCALL_64_after_hwframe+0x44/0xae The buggy address belongs to the object at ffff88816912f380 which belongs to the cache kmalloc-96 of size 96 The buggy address is located 88 bytes inside of 96-byte region [ffff88816912f380, ffff88816912f3e0) The buggy address belongs to the page: page:000000009a1b4e7c refcount:1 mapcount:0 mapping:0000000000000000 index:0x0f flags: 0x17ffffc0000200(slab|node=0|zone=2|lastcpupid=0x1fffff) raw: 0017ffffc0000200 ffffea00044f1100 dead000000000002 ffff88810004c780 raw: 0000000000000000 0000000000200020 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff88816912f280: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc ffff88816912f300: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc >ffff88816912f380: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc ^ ffff88816912f400: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc ffff88816912f480: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc ================================================================== Fixes: c0ea57608b69 ("blktrace: remove debugfs file dentries from struct blk_trace") Signed-off-by: Yu Kuai Reviewed-by: Greg Kroah-Hartman Link: https://lore.kernel.org/r/20220228034354.4047385-1-yukuai3@huawei.com Signed-off-by: Jens Axboe Signed-off-by: Greg Kroah-Hartman

tracing: Add ustring operation to filtering string pointers

2022-03-08T18:14:05Z

[ Upstream commit f37c3bbc635994eda203a6da4ba0f9d05165a8d6 ] Since referencing user space pointers is special, if the user wants to filter on a field that is a pointer to user space, then they need to specify it. Add a ".ustring" attribute to the field name for filters to state that the field is pointing to user space such that the kernel can take the appropriate action to read that pointer. Link: https://lore.kernel.org/all/yt9d8rvmt2jq.fsf@linux.ibm.com/ Fixes: 77360f9bbc7e ("tracing: Add test for user space strings when filtering on string pointers") Tested-by: Sven Schnelle Signed-off-by: Steven Rostedt Signed-off-by: Sasha Levin

tracing: Add test for user space strings when filtering on string pointers

2022-03-08T18:14:04Z

[ Upstream commit 77360f9bbc7e5e2ab7a2c8b4c0244fbbfcfc6f62 ] Pingfan reported that the following causes a fault: echo "filename ~ \"cpu\"" > events/syscalls/sys_enter_openat/filter echo 1 > events/syscalls/sys_enter_at/enable The reason is that trace event filter treats the user space pointer defined by "filename" as a normal pointer to compare against the "cpu" string. The following bug happened: kvm-03-guest16 login: [72198.026181] BUG: unable to handle page fault for address: 00007fffaae8ef60 #PF: supervisor read access in kernel mode #PF: error_code(0x0001) - permissions violation PGD 80000001008b7067 P4D 80000001008b7067 PUD 2393f1067 PMD 2393ec067 PTE 8000000108f47867 Oops: 0001 [#1] PREEMPT SMP PTI CPU: 1 PID: 1 Comm: systemd Kdump: loaded Not tainted 5.14.0-32.el9.x86_64 #1 Hardware name: Red Hat KVM, BIOS 0.5.1 01/01/2011 RIP: 0010:strlen+0x0/0x20 Code: 48 89 f9 74 09 48 83 c1 01 80 39 00 75 f7 31 d2 44 0f b6 04 16 44 88 04 11 48 83 c2 01 45 84 c0 75 ee c3 0f 1f 80 00 00 00 00 <80> 3f 00 74 10 48 89 f8 48 83 c0 01 80 38 00 75 f7 48 29 f8 c3 31 RSP: 0018:ffffb5b900013e48 EFLAGS: 00010246 RAX: 0000000000000018 RBX: ffff8fc1c49ede00 RCX: 0000000000000000 RDX: 0000000000000020 RSI: ffff8fc1c02d601c RDI: 00007fffaae8ef60 RBP: 00007fffaae8ef60 R08: 0005034f4ddb8ea4 R09: 0000000000000000 R10: ffff8fc1c02d601c R11: 0000000000000000 R12: ffff8fc1c8a6e380 R13: 0000000000000000 R14: ffff8fc1c02d6010 R15: ffff8fc1c00453c0 FS: 00007fa86123db40(0000) GS:ffff8fc2ffd00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fffaae8ef60 CR3: 0000000102880001 CR4: 00000000007706e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 PKRU: 55555554 Call Trace: filter_pred_pchar+0x18/0x40 filter_match_preds+0x31/0x70 ftrace_syscall_enter+0x27a/0x2c0 syscall_trace_enter.constprop.0+0x1aa/0x1d0 do_syscall_64+0x16/0x90 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7fa861d88664 The above happened because the kernel tried to access user space directly and triggered a "supervisor read access in kernel mode" fault. Worse yet, the memory could not even be loaded yet, and a SEGFAULT could happen as well. This could be true for kernel space accessing as well. To be even more robust, test both kernel and user space strings. If the string fails to read, then simply have the filter fail. Note, TASK_SIZE is used to determine if the pointer is user or kernel space and the appropriate strncpy_from_kernel/user_nofault() function is used to copy the memory. For some architectures, the compare to TASK_SIZE may always pick user space or kernel space. If it gets it wrong, the only thing is that the filter will fail to match. In the future, this needs to be fixed to have the event denote which should be used. But failing a filter is much better than panicing the machine, and that can be solved later. Link: https://lore.kernel.org/all/20220107044951.22080-1-kernelfans@gmail.com/ Link: https://lkml.kernel.org/r/20220110115532.536088fd@gandalf.local.home Cc: stable@vger.kernel.org Cc: Ingo Molnar Cc: Andrew Morton Cc: Masami Hiramatsu Cc: Tom Zanussi Reported-by: Pingfan Liu Tested-by: Pingfan Liu Fixes: 87a342f5db69d ("tracing/filters: Support filtering for char * strings") Signed-off-by: Steven Rostedt Signed-off-by: Sasha Levin

tracing: Have traceon and traceoff trigger honor the instance

2022-03-02T10:51:12Z

commit 302e9edd54985f584cfc180098f3554774126969 upstream. If a trigger is set on an event to disable or enable tracing within an instance, then tracing should be disabled or enabled in the instance and not at the top level, which is confusing to users. Link: https://lkml.kernel.org/r/20220223223837.14f94ec3@rorschach.local.home Cc: stable@vger.kernel.org Fixes: ae63b31e4d0e2 ("tracing: Separate out trace events from global variables") Tested-by: Daniel Bristot de Oliveira Reviewed-by: Tom Zanussi Signed-off-by: Steven Rostedt (Google) Signed-off-by: Greg Kroah-Hartman

tracing: Dump stacktrace trigger to the corresponding instance

2022-03-02T10:51:11Z

commit ce33c845b030c9cf768370c951bc699470b09fa7 upstream. The stacktrace event trigger is not dumping the stacktrace to the instance where it was enabled, but to the global "instance." Use the private_data, pointing to the trigger file, to figure out the corresponding trace instance, and use it in the trigger action, like snapshot_trigger does. Link: https://lkml.kernel.org/r/afbb0b4f18ba92c276865bc97204d438473f4ebc.1645396236.git.bristot@kernel.org Cc: stable@vger.kernel.org Fixes: ae63b31e4d0e2 ("tracing: Separate out trace events from global variables") Reviewed-by: Tom Zanussi Tested-by: Tom Zanussi Signed-off-by: Daniel Bristot de Oliveira Signed-off-by: Steven Rostedt (Google) Signed-off-by: Greg Kroah-Hartman

tracing: Fix tp_printk option related with tp_printk_stop_on_boot

2022-02-23T11:06:08Z

[ Upstream commit 3203ce39ac0b2a57a84382ec184c7d4a0bede175 ] The kernel parameter "tp_printk_stop_on_boot" starts with "tp_printk" which is the same as another kernel parameter "tp_printk". If "tp_printk" setup is called before the "tp_printk_stop_on_boot", it will override the latter and keep it from being set. This is similar to other kernel parameter issues, such as: Commit 745a600cf1a6 ("um: console: Ignore console= option") or init/do_mounts.c:45 (setup function of "ro" kernel param) Fix it by checking for a "_" right after the "tp_printk" and if that exists do not process the parameter. Link: https://lkml.kernel.org/r/20220208195421.969326-1-jsyoo5b@gmail.com Signed-off-by: JaeSang Yoo [ Fixed up change log and added space after if condition ] Signed-off-by: Steven Rostedt (Google) Signed-off-by: Sasha Levin

bpf: Add MEM_RDONLY for helper args that are pointers to rdonly mem.

2022-02-23T11:05:46Z

commit 216e3cd2f28dbbf1fe86848e0e29e6693b9f0a20 upstream. Some helper functions may modify its arguments, for example, bpf_d_path, bpf_get_stack etc. Previously, their argument types were marked as ARG_PTR_TO_MEM, which is compatible with read-only mem types, such as PTR_TO_RDONLY_BUF. Therefore it's legitimate, but technically incorrect, to modify a read-only memory by passing it into one of such helper functions. This patch tags the bpf_args compatible with immutable memory with MEM_RDONLY flag. The arguments that don't have this flag will be only compatible with mutable memory types, preventing the helper from modifying a read-only memory. The bpf_args that have MEM_RDONLY are compatible with both mutable memory and immutable memory. Signed-off-by: Hao Luo Signed-off-by: Alexei Starovoitov Link: https://lore.kernel.org/bpf/20211217003152.48334-9-haoluo@google.com Cc: stable@vger.kernel.org # 5.16.x Signed-off-by: Greg Kroah-Hartman

tracing: Don't inc err_log entry count if entry allocation fails

2022-02-01T16:29:02Z

commit 67ab5eb71b37b55f7c5522d080a1b42823351776 upstream. tr->n_err_log_entries should only be increased if entry allocation succeeds. Doing it when it fails won't cause any problems other than wasting an entry, but should be fixed anyway. Link: https://lkml.kernel.org/r/cad1ab28f75968db0f466925e7cba5970cec6c29.1643319703.git.zanussi@kernel.org Cc: stable@vger.kernel.org Fixes: 2f754e771b1a6 ("tracing: Don't inc err_log entry count if entry allocation fails") Signed-off-by: Tom Zanussi Signed-off-by: Steven Rostedt (Google) Signed-off-by: Greg Kroah-Hartman