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2026-09-22s390/debug: Fix NULL pointer dereference in debug_info_copy()Mikhail Zaslonko
When debug_register_static() fails, it clears areas, active_pages and active_entries but leaves the area bounds unchanged. Copying such an area, either by opening its view file or via debug_dump(), makes debug_info_copy() dereference the NULL pointers. Skip the copy loop when the source has no areas. Closes: https://lore.kernel.org/r/20260903132123.12F271F00A3F@smtp.kernel.org Fixes: d72541f94512 ("s390/debug: add early tracing support") Signed-off-by: Mikhail Zaslonko <zaslonko@linux.ibm.com> Reviewed-by: Peter Oberparleiter <oberpar@linux.ibm.com> Acked-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2026-09-22s390/debug: Do not register views for failed static debug areasMikhail Zaslonko
__REGISTER_STATIC_DEBUG_INFO() calls debug_register_view() unconditionally, even when debug_register_static() has failed. In that case _debug_register() was never reached and id->debugfs_root_entry is still NULL, so debugfs_create_file() places the view file in the debugfs root directory. For sclp_err this leaves a /sys/kernel/debug/hex_ascii file with nothing to indicate which debug log it belongs to. debug_register_static() is not exported and the macro is its only caller, so let it return an error code and skip the view registration when it fails. No debugfs files are created for such an area then. Reproduce by booting with s390dbf=sclp_err::100000000. The sclp_err registration fails, no s390dbf/sclp_err/ directory is created, and a hex_ascii file appears in the debugfs root instead. Fixes: d72541f94512 ("s390/debug: add early tracing support") Signed-off-by: Mikhail Zaslonko <zaslonko@linux.ibm.com> Reviewed-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2026-09-22s390/debug: Reject NULL debug info in debug_dump()Mikhail Zaslonko
debug_dump() passes id on to debug_info_copy(), which dereferences in->name unchecked. debug_unregister(), debug_set_size() and debug_register_view() guard against a NULL id but debug_dump() does not. Nothing reaches this today, but add the check for consistency. Reported-by: Sashiko <sashiko-bot@kernel.org> Closes: https://lore.kernel.org/all/20260910110147.96E851F000FF@smtp.kernel.org/ Signed-off-by: Mikhail Zaslonko <zaslonko@linux.ibm.com> Reviewed-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2026-09-08s390/debug: Fix race between debug area resize and event loggingMikhail Zaslonko
Trace functions check for non-NULL id->areas without lock to minimize overhead. This opens a race window where a NULL pointer dereference occurs if id->areas is set to NULL (e.g. via echo 0 > ../pages) after the check and before id->lock is taken. Fix this by rechecking id->areas under lock. Signed-off-by: Mikhail Zaslonko <zaslonko@linux.ibm.com> Reviewed-by: Peter Oberparleiter <oberpar@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2026-09-08s390/debug: Do not repeat parameter override notice on debug_set_level()Mikhail Zaslonko
Commit a2cec6863709 ("s390/debug: Add s390dbf kernel parameter") calls debug_get_param() from both debug_info_create() and debug_set_level(). Since debug_get_param() emits the override notice unconditionally, and drivers typically call debug_set_level() right after debug_register(), the same line is printed twice per debug area: s390dbf: 0.0.1234: override level to 6 s390dbf: 0.0.1234: override level to 6 For areas registered per device this is multiplied by the device count. With 's390dbf=0.0.*:6' a system with many DASDs emits a large number of redundant lines during boot. Add a quiet parameter to debug_get_param() and pass quiet=true from debug_set_level(), where the override has already been announced during registration. The remaining callers keep printing the notice. Signed-off-by: Mikhail Zaslonko <zaslonko@linux.ibm.com> Reviewed-by: Peter Oberparleiter <oberpar@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2026-09-08s390/debug: Fix NULL pointer dereference in debug_set_level()Mikhail Zaslonko
Commit a2cec6863709 ("s390/debug: Add s390dbf kernel parameter") incorrectly removed a null-id check from debug_set_level(), introducing a possible NULL pointer dereference for debug-API users that put debug_register() results unchecked into debug_set_level(). Fix this by moving the check from the internal _debug_set_level() variant back to the external debug_set_level() wrapper. Fixes: a2cec6863709 ("s390/debug: Add s390dbf kernel parameter") Signed-off-by: Mikhail Zaslonko <zaslonko@linux.ibm.com> Reviewed-by: Peter Oberparleiter <oberpar@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2026-08-13s390/debug: Fix deadlock during unregisterPeter Oberparleiter
Unregistering an s390dbf debug area while one of the associated debugfs files is being written to can cause a deadlock: $ echo >.../vmur/level $ rmmod vmur =================================================== debugfs write debugfs_file_get() debug_unregister() mutex_lock(debug_mutex) debugfs_remove() wait for debugfs_file_put() debug_file_ops.write() debug_input() mutex_lock(debug_mutex) ==> DEADLOCK Fix this by splitting debug_unregister() into an s390dbf and debugfs part, and running only the s390dbf part with debug_mutex locked. Fixes: 9372a82892c2 ("s390/debug: fix debug area life cycle") Signed-off-by: Peter Oberparleiter <oberpar@linux.ibm.com> Reviewed-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2026-05-26s390/debug: Remove s390dbf_sysctl_header variableHeiko Carstens
allmodconfig with clang W=1 points out an unused global variable: arch/s390/kernel/debug.c:1237:33: error: variable 's390dbf_sysctl_header' set but not used [-Werror,-Wunused-but-set-global] Just remove the variable. There is no point in adding error handling for a failing register_sysctl() call. Reviewed-by: Christian Borntraeger <borntraeger@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
2026-05-11s390/debug: Add s390dbf kernel parameterPeter Oberparleiter
Problem determination using s390dbf logging sometimes requires changing the default logging level or log area size. While this is possible using sysfs interfaces, there is no easy way to adjust these parameters for early boot code that emits logs before userspace is available. Add an s390dbf kernel parameter to address this shortcoming. The parameter can be used to specify log level and area size (in units of pages). A level of '-' turns logging off for an area. Logs can be identified by name or a shell-style pattern. Parameter format: s390dbf=<name|pattern>:[<level>|-]:[<pages>][,...] Example: s390dbf=cio*:6:128,sclp_err::2 Specified parameters are applied immediately during debug area registration for regular log areas. For early, static debug areas, log levels are changed during early_param() parsing, while size changes are applied at arch_initcall-time. Signed-off-by: Peter Oberparleiter <oberpar@linux.ibm.com> Tested-by: Vineeth Vijayan <vneethv@linux.ibm.com> Reviewed-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
2026-04-28s390/debug: Reject zero-length input in debug_input_flush_fn()Vasily Gorbik
debug_input_flush_fn() always copies one byte from the userspace buffer with copy_from_user() regardless of the supplied write length. A zero-length write therefore reads one byte beyond the caller's buffer. If the stale byte happens to be '-' or a digit the debug log is silently flushed. With an unmapped buffer the call returns -EFAULT. Reject zero-length writes before copying from userspace. Cc: stable@vger.kernel.org # v5.10+ Acked-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
2026-04-28s390/debug: Reject zero-length input before trimming a newlinePengpeng Hou
debug_get_user_string() duplicates the userspace buffer with memdup_user_nul() and then unconditionally looks at buffer[user_len - 1] to strip a trailing newline. A zero-length write reaches this helper unchanged, so the newline trim reads before the start of the allocated buffer. Reject empty writes before accessing the last input byte. Fixes: 66a464dbc8e0 ("[PATCH] s390: debug feature changes") Cc: stable@vger.kernel.org Signed-off-by: Pengpeng Hou <pengpeng@iscas.ac.cn> Reviewed-by: Benjamin Block <bblock@linux.ibm.com> Reviewed-by: Vasily Gorbik <gor@linux.ibm.com> Tested-by: Vasily Gorbik <gor@linux.ibm.com> Link: https://lore.kernel.org/r/20260417073530.96002-1-pengpeng@iscas.ac.cn Signed-off-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
2026-02-21Convert 'alloc_obj' family to use the new default GFP_KERNEL argumentLinus Torvalds
This was done entirely with mindless brute force, using git grep -l '\<k[vmz]*alloc_objs*(.*, GFP_KERNEL)' | xargs sed -i 's/\(alloc_objs*(.*\), GFP_KERNEL)/\1)/' to convert the new alloc_obj() users that had a simple GFP_KERNEL argument to just drop that argument. Note that due to the extreme simplicity of the scripting, any slightly more complex cases spread over multiple lines would not be triggered: they definitely exist, but this covers the vast bulk of the cases, and the resulting diff is also then easier to check automatically. For the same reason the 'flex' versions will be done as a separate conversion. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2026-02-21treewide: Replace kmalloc with kmalloc_obj for non-scalar typesKees Cook
This is the result of running the Coccinelle script from scripts/coccinelle/api/kmalloc_objs.cocci. The script is designed to avoid scalar types (which need careful case-by-case checking), and instead replace kmalloc-family calls that allocate struct or union object instances: Single allocations: kmalloc(sizeof(TYPE), ...) are replaced with: kmalloc_obj(TYPE, ...) Array allocations: kmalloc_array(COUNT, sizeof(TYPE), ...) are replaced with: kmalloc_objs(TYPE, COUNT, ...) Flex array allocations: kmalloc(struct_size(PTR, FAM, COUNT), ...) are replaced with: kmalloc_flex(*PTR, FAM, COUNT, ...) (where TYPE may also be *VAR) The resulting allocations no longer return "void *", instead returning "TYPE *". Signed-off-by: Kees Cook <kees@kernel.org>
2026-02-18s390/debug: Convert debug area lock from a spinlock to a raw spinlockBenjamin Block
With PREEMPT_RT as potential configuration option, spinlock_t is now considered as a sleeping lock, and thus might cause issues when used in an atomic context. But even with PREEMPT_RT as potential configuration option, raw_spinlock_t remains as a true spinning lock/atomic context. This creates potential issues with the s390 debug/tracing feature. The functions to trace errors are called in various contexts, including under lock of raw_spinlock_t, and thus the used spinlock_t in each debug area is in violation of the locking semantics. Here are two examples involving failing PCI Read accesses that are traced while holding `pci_lock` in `drivers/pci/access.c`: ============================= [ BUG: Invalid wait context ] 6.19.0-devel #18 Not tainted ----------------------------- bash/3833 is trying to lock: 0000027790baee30 (&rc->lock){-.-.}-{3:3}, at: debug_event_common+0xfc/0x300 other info that might help us debug this: context-{5:5} 5 locks held by bash/3833: #0: 0000027efbb29450 (sb_writers#3){.+.+}-{0:0}, at: ksys_write+0x7c/0xf0 #1: 00000277f0504a90 (&of->mutex#2){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x13e/0x260 #2: 00000277beed8c18 (kn->active#339){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x164/0x260 #3: 00000277e9859190 (&dev->mutex){....}-{4:4}, at: pci_dev_lock+0x2e/0x40 #4: 00000383068a7708 (pci_lock){....}-{2:2}, at: pci_bus_read_config_dword+0x4a/0xb0 stack backtrace: CPU: 6 UID: 0 PID: 3833 Comm: bash Kdump: loaded Not tainted 6.19.0-devel #18 PREEMPTLAZY Hardware name: IBM 9175 ME1 701 (LPAR) Call Trace: [<00000383048afec2>] dump_stack_lvl+0xa2/0xe8 [<00000383049ba166>] __lock_acquire+0x816/0x1660 [<00000383049bb1fa>] lock_acquire+0x24a/0x370 [<00000383059e3860>] _raw_spin_lock_irqsave+0x70/0xc0 [<00000383048bbb6c>] debug_event_common+0xfc/0x300 [<0000038304900b0a>] __zpci_load+0x17a/0x1f0 [<00000383048fad88>] pci_read+0x88/0xd0 [<00000383054cbce0>] pci_bus_read_config_dword+0x70/0xb0 [<00000383054d55e4>] pci_dev_wait+0x174/0x290 [<00000383054d5a3e>] __pci_reset_function_locked+0xfe/0x170 [<00000383054d9b30>] pci_reset_function+0xd0/0x100 [<00000383054ee21a>] reset_store+0x5a/0x80 [<0000038304e98758>] kernfs_fop_write_iter+0x1e8/0x260 [<0000038304d995da>] new_sync_write+0x13a/0x180 [<0000038304d9c5d0>] vfs_write+0x200/0x330 [<0000038304d9c88c>] ksys_write+0x7c/0xf0 [<00000383059cfa80>] __do_syscall+0x210/0x500 [<00000383059e4c06>] system_call+0x6e/0x90 INFO: lockdep is turned off. ============================= [ BUG: Invalid wait context ] 6.19.0-devel #3 Not tainted ----------------------------- bash/6861 is trying to lock: 0000009da05c7430 (&rc->lock){-.-.}-{3:3}, at: debug_event_common+0xfc/0x300 other info that might help us debug this: context-{5:5} 5 locks held by bash/6861: #0: 000000acff404450 (sb_writers#3){.+.+}-{0:0}, at: ksys_write+0x7c/0xf0 #1: 000000acff41c490 (&of->mutex#2){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x13e/0x260 #2: 0000009da36937d8 (kn->active#75){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x164/0x260 #3: 0000009dd15250d0 (&zdev->state_lock){+.+.}-{4:4}, at: enable_slot+0x2e/0xc0 #4: 000001a19682f708 (pci_lock){....}-{2:2}, at: pci_bus_read_config_byte+0x42/0xa0 stack backtrace: CPU: 16 UID: 0 PID: 6861 Comm: bash Kdump: loaded Not tainted 6.19.0-devel #3 PREEMPTLAZY Hardware name: IBM 9175 ME1 701 (LPAR) Call Trace: [<000001a194837ec2>] dump_stack_lvl+0xa2/0xe8 [<000001a194942166>] __lock_acquire+0x816/0x1660 [<000001a1949431fa>] lock_acquire+0x24a/0x370 [<000001a19596b810>] _raw_spin_lock_irqsave+0x70/0xc0 [<000001a194843b6c>] debug_event_common+0xfc/0x300 [<000001a194888b0a>] __zpci_load+0x17a/0x1f0 [<000001a194882d88>] pci_read+0x88/0xd0 [<000001a195453b88>] pci_bus_read_config_byte+0x68/0xa0 [<000001a195457bc2>] pci_setup_device+0x62/0xad0 [<000001a195458e70>] pci_scan_single_device+0x90/0xe0 [<000001a19488a0f6>] zpci_bus_scan_device+0x46/0x80 [<000001a19547f958>] enable_slot+0x98/0xc0 [<000001a19547f134>] power_write_file+0xc4/0x110 [<000001a194e20758>] kernfs_fop_write_iter+0x1e8/0x260 [<000001a194d215da>] new_sync_write+0x13a/0x180 [<000001a194d245d0>] vfs_write+0x200/0x330 [<000001a194d2488c>] ksys_write+0x7c/0xf0 [<000001a195957a30>] __do_syscall+0x210/0x500 [<000001a19596cbb6>] system_call+0x6e/0x90 INFO: lockdep is turned off. Since it is desired to keep it possible to create trace records in most situations, including this particular case (failing PCI config space accesses are relevant), convert the used spinlock_t in `struct debug_info` to raw_spinlock_t. The impact is small, as the debug area lock only protects bounded memory access without external dependencies, apart from one function debug_set_size() where kfree() is implicitly called with the lock held. Move debug_info_free() out of this lock, to keep remove this external dependency. Acked-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Benjamin Block <bblock@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2025-11-24s390: Remove KMSG_COMPONENT macroHeiko Carstens
The KMSG_COMPONENT macro is a leftover of the s390 specific "kernel message catalog" which never made it upstream. Remove the macro in order to get rid of a pointless indirection. Replace all users with the string it defines. In almost all cases this leads to a simple replacement like this: - #define KMSG_COMPONENT "appldata" - #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt + #define pr_fmt(fmt) "appldata: " fmt Except for some special cases this is just mechanical/scripted work. Acked-by: Thomas Richter <tmricht@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2025-09-09s390/debug: Replace kmalloc() + copy_from_user() with memdup_user_nul()Thorsten Blum
Replace kmalloc() followed by copy_from_user() with memdup_user_nul() to improve and simplify debug_get_user_string(). Remove the manual NUL-termination. No functional changes intended. Signed-off-by: Thorsten Blum <thorsten.blum@linux.dev> Reviewed-by: Niklas Schnelle <schnelle@linux.ibm.com> Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
2025-08-06s390/debug: Fix typo in debug_sprintf_format_fn() commentTigran Mkrtchyan
Signed-off-by: Tigran Mkrtchyan <tigran.mkrtchyan@desy.de> Link: https://lore.kernel.org/r/20250804093321.434674-1-tigran.mkrtchyan@desy.de Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
2025-04-17s390: Remove optional third argument of strscpy() if possibleHeiko Carstens
The third argument of strscpy() is optional and can be left away iff the destination is an array and the maximum size of the copy is the size of destination. Remove the third argument for those cases where this is possible. Acked-by: Alexander Gordeev <agordeev@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2025-01-28treewide: const qualify ctl_tables where applicableJoel Granados
Add the const qualifier to all the ctl_tables in the tree except for watchdog_hardlockup_sysctl, memory_allocation_profiling_sysctls, loadpin_sysctl_table and the ones calling register_net_sysctl (./net, drivers/inifiniband dirs). These are special cases as they use a registration function with a non-const qualified ctl_table argument or modify the arrays before passing them on to the registration function. Constifying ctl_table structs will prevent the modification of proc_handler function pointers as the arrays would reside in .rodata. This is made possible after commit 78eb4ea25cd5 ("sysctl: treewide: constify the ctl_table argument of proc_handlers") constified all the proc_handlers. Created this by running an spatch followed by a sed command: Spatch: virtual patch @ depends on !(file in "net") disable optional_qualifier @ identifier table_name != { watchdog_hardlockup_sysctl, iwcm_ctl_table, ucma_ctl_table, memory_allocation_profiling_sysctls, loadpin_sysctl_table }; @@ + const struct ctl_table table_name [] = { ... }; sed: sed --in-place \ -e "s/struct ctl_table .table = &uts_kern/const struct ctl_table *table = \&uts_kern/" \ kernel/utsname_sysctl.c Reviewed-by: Song Liu <song@kernel.org> Acked-by: Steven Rostedt (Google) <rostedt@goodmis.org> # for kernel/trace/ Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> # SCSI Reviewed-by: Darrick J. Wong <djwong@kernel.org> # xfs Acked-by: Jani Nikula <jani.nikula@intel.com> Acked-by: Corey Minyard <cminyard@mvista.com> Acked-by: Wei Liu <wei.liu@kernel.org> Acked-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Bill O'Donnell <bodonnel@redhat.com> Acked-by: Baoquan He <bhe@redhat.com> Acked-by: Ashutosh Dixit <ashutosh.dixit@intel.com> Acked-by: Anna Schumaker <anna.schumaker@oracle.com> Signed-off-by: Joel Granados <joel.granados@kernel.org>
2024-12-16s390/pci: Add pci_msg debug view to PCI reportNiklas Schnelle
Using the newly introduced debug_dump() mechanism add formatted content of pci_debug_msg_id to the PCI report. The formatting is based on the existing sprintf format but removes caller pointer and area index and adds an column header. This will allow the platform to collect this log data together with hardware errors. This sets the reverse flag such that the newest log entries get added to the PCI report even if not all debug log entries fit. Reviewed-by: Halil Pasic <pasic@linux.ibm.com> Co-developed-by: Halil Pasic <pasic@linux.ibm.com> Signed-off-by: Halil Pasic <pasic@linux.ibm.com> Signed-off-by: Niklas Schnelle <schnelle@linux.ibm.com> Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
2024-12-16s390/debug: Add a reverse mode for debug_dump()Niklas Schnelle
In this mode debug_dump() writes the debug log starting at the newest entry followed by earlier entries. To this end add a debug_prev_entry() helper analogous to debug_next_entry() a helper to get the latest entry which is one before the active entry and a helper to iterate either forward or backward. Reviewed-by: Halil Pasic <pasic@linux.ibm.com> Co-developed-by: Halil Pasic <pasic@linux.ibm.com> Signed-off-by: Halil Pasic <pasic@linux.ibm.com> Signed-off-by: Niklas Schnelle <schnelle@linux.ibm.com> Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
2024-12-16s390/debug: Add debug_dump() to write debug view to a string bufferNiklas Schnelle
The debug_dump() function allows to get the content of a debug log and view pair in a string buffer. One future application of this is to provide debug logs to the platform to be collected with hardware error logs during recovery. Reviewed-by: Halil Pasic <pasic@linux.ibm.com> Co-developed-by: Halil Pasic <pasic@linux.ibm.com> Signed-off-by: Halil Pasic <pasic@linux.ibm.com> Signed-off-by: Niklas Schnelle <schnelle@linux.ibm.com> Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
2024-12-16s390/debug: Split private data alloc/free out of file operationsNiklas Schnelle
Split the allocation respectively freeing of file_private_info_t out of open() respectively close(). This will be used in a follow on change to access to debug views without going through the s390dbf filesystem. Reviewed-by: Halil Pasic <pasic@linux.ibm.com> Signed-off-by: Niklas Schnelle <schnelle@linux.ibm.com> Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
2024-12-16s390/debug: Simplify and document debug_next_entry() logicNiklas Schnelle
Contrary to convention debug_next_entry() returns a falsy 0 value if there are more entries and a truthy 1 value when there are no more entries. As there is only one caller just reverse this logic to be less surprising and document the behavior in a kdoc comment. Also replace the goto with an early return. In the future this allows using it in a do {} while (debug_next_entry(...)) loop. Reviewed-by: Halil Pasic <pasic@linux.ibm.com> Signed-off-by: Niklas Schnelle <schnelle@linux.ibm.com> Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
2024-11-21s390/debug: Pass in and enforce output buffer size for format handlersNiklas Schnelle
The s390dbf format handler rely on being passed an output buffer sized such that their output will always fit and then use plain sprintf() to write to it. While only supplied data from other kernel components this still potentially allows buffer overwrite if callers are not careful. Instead just pass in the size of the output buffer and use scnprintf() instead of sprintf() and strscpy() instead of strcpy(). The latter also allows us to get rid of a separate strlen() call. Signed-off-by: Niklas Schnelle <schnelle@linux.ibm.com> Reviewed-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2024-10-25s390: Fix various typosHeiko Carstens
Run codespell on arch/s390 and drivers/s390 and fix all typos. Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2024-09-27[tree-wide] finally take no_llseek outAl Viro
no_llseek had been defined to NULL two years ago, in commit 868941b14441 ("fs: remove no_llseek") To quote that commit, At -rc1 we'll need do a mechanical removal of no_llseek - git grep -l -w no_llseek | grep -v porting.rst | while read i; do sed -i '/\<no_llseek\>/d' $i done would do it. Unfortunately, that hadn't been done. Linus, could you do that now, so that we could finally put that thing to rest? All instances are of the form .llseek = no_llseek, so it's obviously safe. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2024-07-24sysctl: treewide: constify the ctl_table argument of proc_handlersJoel Granados
const qualify the struct ctl_table argument in the proc_handler function signatures. This is a prerequisite to moving the static ctl_table structs into .rodata data which will ensure that proc_handler function pointers cannot be modified. This patch has been generated by the following coccinelle script: ``` virtual patch @r1@ identifier ctl, write, buffer, lenp, ppos; identifier func !~ "appldata_(timer|interval)_handler|sched_(rt|rr)_handler|rds_tcp_skbuf_handler|proc_sctp_do_(hmac_alg|rto_min|rto_max|udp_port|alpha_beta|auth|probe_interval)"; @@ int func( - struct ctl_table *ctl + const struct ctl_table *ctl ,int write, void *buffer, size_t *lenp, loff_t *ppos); @r2@ identifier func, ctl, write, buffer, lenp, ppos; @@ int func( - struct ctl_table *ctl + const struct ctl_table *ctl ,int write, void *buffer, size_t *lenp, loff_t *ppos) { ... } @r3@ identifier func; @@ int func( - struct ctl_table * + const struct ctl_table * ,int , void *, size_t *, loff_t *); @r4@ identifier func, ctl; @@ int func( - struct ctl_table *ctl + const struct ctl_table *ctl ,int , void *, size_t *, loff_t *); @r5@ identifier func, write, buffer, lenp, ppos; @@ int func( - struct ctl_table * + const struct ctl_table * ,int write, void *buffer, size_t *lenp, loff_t *ppos); ``` * Code formatting was adjusted in xfs_sysctl.c to comply with code conventions. The xfs_stats_clear_proc_handler, xfs_panic_mask_proc_handler and xfs_deprecated_dointvec_minmax where adjusted. * The ctl_table argument in proc_watchdog_common was const qualified. This is called from a proc_handler itself and is calling back into another proc_handler, making it necessary to change it as part of the proc_handler migration. Co-developed-by: Thomas Weißschuh <linux@weissschuh.net> Signed-off-by: Thomas Weißschuh <linux@weissschuh.net> Co-developed-by: Joel Granados <j.granados@samsung.com> Signed-off-by: Joel Granados <j.granados@samsung.com>
2023-10-10S390: Remove now superfluous sentinel elem from ctl_table arraysJoel Granados
This commit comes at the tail end of a greater effort to remove the empty elements at the end of the ctl_table arrays (sentinels) which will reduce the overall build time size of the kernel and run time memory bloat by ~64 bytes per sentinel (further information Link : https://lore.kernel.org/all/ZO5Yx5JFogGi%2FcBo@bombadil.infradead.org/) Remove the sentinel element from appldata_table, s390dbf_table, topology_ctl_table, cmm_table and page_table_sysctl. Reduced the memory allocation in appldata_register_ops by 1 effectively removing the sentinel from ops->ctl_table. This removal is safe because register_sysctl_sz and register_sysctl use the array size in addition to checking for the sentinel. Tested-by: Alexander Gordeev <agordeev@linux.ibm.com> Acked-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Joel Granados <j.granados@samsung.com> Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
2023-04-13s390/debug: replace zero-length array with flexible-array memberHeiko Carstens
There are numerous patches which convert zero-length arrays with a flexible-array member. Convert the remaining s390 occurrences. Suggested-by: Gustavo A. R. Silva <gustavoars@kernel.org> Link: https://github.com/KSPP/linux/issues/78 Link: https://gcc.gnu.org/pipermail/gcc-patches/2022-October/602902.html Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2023-03-20s390: simplify one-level syctl registration for s390dbf_tableLuis Chamberlain
There is no need to declare an extra tables to just create directory, this can be easily be done with a prefix path with register_sysctl(). Simplify this registration. Signed-off-by: Luis Chamberlain <mcgrof@kernel.org> Link: https://lore.kernel.org/r/20230310234525.3986352-3-mcgrof@kernel.org Reviewed-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2022-11-23s390/debug: remove function type castHeiko Carstens
clang warns about an incompatible function type cast: CC arch/s390/kernel/debug.o arch/s390/kernel/debug.c:142:2: error: cast from 'int (*)(debug_info_t *, struct debug_view *, char *, debug_sprintf_entry_t *)' (aka 'int (*)(struct debug_info *, struct debug_view *, char *, debug_sprintf_entry_t *)') to 'debug_format_proc_t *' (aka 'int (*)(struct debug_info *, struct debug_view *, char *, const char *)') converts to incompatible function type [-Werror,-Wcast-function-type-strict] (debug_format_proc_t *)&debug_sprintf_format_fn, ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Get rid of this warning by changing debug_sprintf_format_fn() so it matches the debug_format_proc_t function type, and do the cast of the last parameter within the function itself. This is the standard way of handling such cases anyway. Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
2022-08-30s390: move from strlcpy with unused retval to strscpyWolfram Sang
Follow the advice of the below link and prefer 'strscpy' in this subsystem. Conversion is 1:1 because the return value is not used. Generated by a coccinelle script. Link: https://lore.kernel.org/r/CAHk-=wgfRnXz0W3D37d01q3JFkr_i_uTL=V6A6G1oUZcprmknw@mail.gmail.com/ Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Acked-by: Jakub Kicinski <kuba@kernel.org> Acked-by: Benjamin Block <bblock@linux.ibm.com> Acked-by: Alexandra Winter <wintera@linux.ibm.com> Link: https://lore.kernel.org/r/20220818205948.6360-1-wsa+renesas@sang-engineering.com Link: https://lore.kernel.org/r/20220818210102.7301-1-wsa+renesas@sang-engineering.com [gor@linux.ibm.com: squashed two changes linked above together] Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2021-08-25s390/sclp: add tracing of SCLP interactionsPeter Oberparleiter
Add tracing of interactions between the SCLP base driver, firmware and other drivers to support problem determination in case of SCLP-related issues. For that purpose this patch introduces two new s390dbf debug areas: - sclp: An abbreviated log of all common interactions - sclp_err: A full log of failed or abnormal interactions Tracing of full SCCB contents can be enabled for the sclp area by setting its debug level to maximum (6). Overview of added trace events: * Firmware interaction: - SRV1: Service call about to be issued - SRV2: Service call was issued - INT: Interrupt received * Driver interaction: - RQAD: Request was added - RQOK: Request success - RQAB: Request aborted - RQTM: Request timed out - REG: Event listener registered - UREG: Event listener unregistered - EVNT: Event callback - STCG: State-change callback * Abnormal events: - TMO: A timeout occurred - UNEX: Unexpected SCCB completion * Other (not traced at default level): - SYN1: Synchronous wait start - SYN2: Synchronous wait end Since the SCLP interface is used by console drivers this patch also moves s390dbf printks outside the critical section protected by debug area locks to prevent a potential deadlock that would otherwise be introduced between console_owner --> sclp_lock --> sclp_debug.lock. Signed-off-by: Peter Oberparleiter <oberpar@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2021-08-25s390/debug: add early tracing supportPeter Oberparleiter
Debug areas can currently only be used after s390dbf initialization which occurs as a postcore_initcall. This is too late for tracing earlier code such as that related to console_init(). This patch introduces a macro for defining a statically initialized debug area that can be used to trace very early code. The macro is made available for built-in code only because modules are never running during early boot. Example usage: 1. Define static debug area: DEFINE_STATIC_DEBUG_INFO(my_debug, "my_debug", 4, 1, 16, &debug_hex_ascii_view); 2. Add trace entry: debug_event(&my_debug, 0, "DATA", 4); Note: The debug area is automatically registered in debugfs during boot. A driver must not call any of the debug_register()/_unregister() functions on a static debug_info_t! Signed-off-by: Peter Oberparleiter <oberpar@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2021-08-25s390/debug: fix debug area life cyclePeter Oberparleiter
Currently allocation and registration of s390dbf debug areas are tied together. As a result, a debug area cannot be unregistered and re-registered while any process has an associated debugfs file open. Fix this by splitting alloc/release from register/unregister. Signed-off-by: Peter Oberparleiter <oberpar@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2021-08-25s390/debug: keep debug data on resizePeter Oberparleiter
Any previously recorded s390dbf debug data is reset when a debug area is resized using the 'pages' sysfs attribute. This can make live-debugging unnecessarily complex. Fix this by copying existing debug data to the newly allocated debug area when resizing. Signed-off-by: Peter Oberparleiter <oberpar@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2021-06-18s390/debug: Remove pointer obfuscationPeter Oberparleiter
When read via debugfs, s390dbf debug-views print the kernel address of the call-site that created a trace entry. The kernel's %p pointer hashing feature obfuscates this address, and commit 860ec7c6e21c ("s390/debug: use pK for kernel pointers") made this obfuscation configurable via the kptr_restrict sysctl. Obfuscation of kernel address data printed via s390dbf debug-views does not add any additional protection since the associated debugfs files are only accessible to the root user that typically has enough other means to obtain kernel address data. Also trace payload data may contain binary representations of kernel addresses as part of logged data structues. Requiring such payload data to be obfuscated as well would be impractical and greatly diminish the use of s390dbf. Therefore completely remove pointer obfuscation from s390dbf debug-views. Reviewed-by: Steffen Maier <maier@linux.ibm.com> Acked-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Peter Oberparleiter <oberpar@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2021-02-13s390/debug: use union tod_clockHeiko Carstens
Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2020-08-11s390/debug: debug feature version 3Mikhail Zaslonko
Change __debug_entry structure in the following way: - remove redundant union - Field containing cpuid is expanded to 16 bits. 8-bit width was not enough since we already support up to 512 cpus. - Field containing the timestamp is expanded to 60 bits. The timestamp itself is now stored in the absolute Unix time format in microseconds taking the Epoch Index into acount. Adjust default header for debug entries by setting minimum width for cpuid to 4 digits. Reviewed-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Mikhail Zaslonko <zaslonko@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2020-06-29s390/debug: remove raw viewHeiko Carstens
There is not a single user of the debug raw view. Therefore remove it before anybody uses it. If anybody would make use of the view it would expose the struct __debug_entry definition to userspace and really would make it uapi. This wouldn't be good, since the definition is suboptimal and needs to be changed. Right now the structure definition is only defined to be uapi, however there is no user. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2020-06-23s390/debug: avoid kernel warning on too large number of pagesChristian Borntraeger
When specifying insanely large debug buffers a kernel warning is printed. The debug code does handle the error gracefully, though. Instead of duplicating the check let us silence the warning to avoid crashes when panic_on_warn is used. Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2020-04-27sysctl: pass kernel pointers to ->proc_handlerChristoph Hellwig
Instead of having all the sysctl handlers deal with user pointers, which is rather hairy in terms of the BPF interaction, copy the input to and from userspace in common code. This also means that the strings are always NUL-terminated by the common code, making the API a little bit safer. As most handler just pass through the data to one of the common handlers a lot of the changes are mechnical. Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Andrey Ignatov <rdna@fb.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2019-07-05docs: s390: unify and update s390dbf kdocs at debug.cSteffen Maier
For non-static-inlines, debug.c already had non-compliant function header docs. So move the pure prototype kdocs of ("s390: include/asm/debug.h add kerneldoc markups") from debug.h to debug.c and merge them with the old function docs. Also, I had the impression that kdoc typically is at the implementation in the compile unit rather than at the prototype in the header file. While at it, update the short kdoc description to distinguish the different functions. And a few more consistency cleanups. Added a new kdoc for debug_set_critical() since debug.h comments it as part of the API. Signed-off-by: Steffen Maier <maier@linux.ibm.com> Acked-by: Christian Borntraeger <borntraeger@de.ibm.com> Message-Id: <1562149189-1417-3-git-send-email-maier@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2019-01-28s390: no need to check return value of debugfs_create functionsGreg Kroah-Hartman
When calling debugfs functions, there is no need to ever check the return value. The function can work or not, but the code logic should never do something different based on this. Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Kees Cook <keescook@chromium.org> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: Hendrik Brueckner <brueckner@linux.vnet.ibm.com> Cc: linux-s390@vger.kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2018-06-12treewide: kmalloc() -> kmalloc_array()Kees Cook
The kmalloc() function has a 2-factor argument form, kmalloc_array(). This patch replaces cases of: kmalloc(a * b, gfp) with: kmalloc_array(a * b, gfp) as well as handling cases of: kmalloc(a * b * c, gfp) with: kmalloc(array3_size(a, b, c), gfp) as it's slightly less ugly than: kmalloc_array(array_size(a, b), c, gfp) This does, however, attempt to ignore constant size factors like: kmalloc(4 * 1024, gfp) though any constants defined via macros get caught up in the conversion. Any factors with a sizeof() of "unsigned char", "char", and "u8" were dropped, since they're redundant. The tools/ directory was manually excluded, since it has its own implementation of kmalloc(). The Coccinelle script used for this was: // Fix redundant parens around sizeof(). @@ type TYPE; expression THING, E; @@ ( kmalloc( - (sizeof(TYPE)) * E + sizeof(TYPE) * E , ...) | kmalloc( - (sizeof(THING)) * E + sizeof(THING) * E , ...) ) // Drop single-byte sizes and redundant parens. @@ expression COUNT; typedef u8; typedef __u8; @@ ( kmalloc( - sizeof(u8) * (COUNT) + COUNT , ...) | kmalloc( - sizeof(__u8) * (COUNT) + COUNT , ...) | kmalloc( - sizeof(char) * (COUNT) + COUNT , ...) | kmalloc( - sizeof(unsigned char) * (COUNT) + COUNT , ...) | kmalloc( - sizeof(u8) * COUNT + COUNT , ...) | kmalloc( - sizeof(__u8) * COUNT + COUNT , ...) | kmalloc( - sizeof(char) * COUNT + COUNT , ...) | kmalloc( - sizeof(unsigned char) * COUNT + COUNT , ...) ) // 2-factor product with sizeof(type/expression) and identifier or constant. @@ type TYPE; expression THING; identifier COUNT_ID; constant COUNT_CONST; @@ ( - kmalloc + kmalloc_array ( - sizeof(TYPE) * (COUNT_ID) + COUNT_ID, sizeof(TYPE) , ...) | - kmalloc + kmalloc_array ( - sizeof(TYPE) * COUNT_ID + COUNT_ID, sizeof(TYPE) , ...) | - kmalloc + kmalloc_array ( - sizeof(TYPE) * (COUNT_CONST) + COUNT_CONST, sizeof(TYPE) , ...) | - kmalloc + kmalloc_array ( - sizeof(TYPE) * COUNT_CONST + COUNT_CONST, sizeof(TYPE) , ...) | - kmalloc + kmalloc_array ( - sizeof(THING) * (COUNT_ID) + COUNT_ID, sizeof(THING) , ...) | - kmalloc + kmalloc_array ( - sizeof(THING) * COUNT_ID + COUNT_ID, sizeof(THING) , ...) | - kmalloc + kmalloc_array ( - sizeof(THING) * (COUNT_CONST) + COUNT_CONST, sizeof(THING) , ...) | - kmalloc + kmalloc_array ( - sizeof(THING) * COUNT_CONST + COUNT_CONST, sizeof(THING) , ...) ) // 2-factor product, only identifiers. @@ identifier SIZE, COUNT; @@ - kmalloc + kmalloc_array ( - SIZE * COUNT + COUNT, SIZE , ...) // 3-factor product with 1 sizeof(type) or sizeof(expression), with // redundant parens removed. @@ expression THING; identifier STRIDE, COUNT; type TYPE; @@ ( kmalloc( - sizeof(TYPE) * (COUNT) * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | kmalloc( - sizeof(TYPE) * (COUNT) * STRIDE + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | kmalloc( - sizeof(TYPE) * COUNT * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | kmalloc( - sizeof(TYPE) * COUNT * STRIDE + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | kmalloc( - sizeof(THING) * (COUNT) * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) | kmalloc( - sizeof(THING) * (COUNT) * STRIDE + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) | kmalloc( - sizeof(THING) * COUNT * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) | kmalloc( - sizeof(THING) * COUNT * STRIDE + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) ) // 3-factor product with 2 sizeof(variable), with redundant parens removed. @@ expression THING1, THING2; identifier COUNT; type TYPE1, TYPE2; @@ ( kmalloc( - sizeof(TYPE1) * sizeof(TYPE2) * COUNT + array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2)) , ...) | kmalloc( - sizeof(TYPE1) * sizeof(THING2) * (COUNT) + array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2)) , ...) | kmalloc( - sizeof(THING1) * sizeof(THING2) * COUNT + array3_size(COUNT, sizeof(THING1), sizeof(THING2)) , ...) | kmalloc( - sizeof(THING1) * sizeof(THING2) * (COUNT) + array3_size(COUNT, sizeof(THING1), sizeof(THING2)) , ...) | kmalloc( - sizeof(TYPE1) * sizeof(THING2) * COUNT + array3_size(COUNT, sizeof(TYPE1), sizeof(THING2)) , ...) | kmalloc( - sizeof(TYPE1) * sizeof(THING2) * (COUNT) + array3_size(COUNT, sizeof(TYPE1), sizeof(THING2)) , ...) ) // 3-factor product, only identifiers, with redundant parens removed. @@ identifier STRIDE, SIZE, COUNT; @@ ( kmalloc( - (COUNT) * STRIDE * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) | kmalloc( - COUNT * (STRIDE) * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) | kmalloc( - COUNT * STRIDE * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | kmalloc( - (COUNT) * (STRIDE) * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) | kmalloc( - COUNT * (STRIDE) * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | kmalloc( - (COUNT) * STRIDE * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | kmalloc( - (COUNT) * (STRIDE) * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | kmalloc( - COUNT * STRIDE * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) ) // Any remaining multi-factor products, first at least 3-factor products, // when they're not all constants... @@ expression E1, E2, E3; constant C1, C2, C3; @@ ( kmalloc(C1 * C2 * C3, ...) | kmalloc( - (E1) * E2 * E3 + array3_size(E1, E2, E3) , ...) | kmalloc( - (E1) * (E2) * E3 + array3_size(E1, E2, E3) , ...) | kmalloc( - (E1) * (E2) * (E3) + array3_size(E1, E2, E3) , ...) | kmalloc( - E1 * E2 * E3 + array3_size(E1, E2, E3) , ...) ) // And then all remaining 2 factors products when they're not all constants, // keeping sizeof() as the second factor argument. @@ expression THING, E1, E2; type TYPE; constant C1, C2, C3; @@ ( kmalloc(sizeof(THING) * C2, ...) | kmalloc(sizeof(TYPE) * C2, ...) | kmalloc(C1 * C2 * C3, ...) | kmalloc(C1 * C2, ...) | - kmalloc + kmalloc_array ( - sizeof(TYPE) * (E2) + E2, sizeof(TYPE) , ...) | - kmalloc + kmalloc_array ( - sizeof(TYPE) * E2 + E2, sizeof(TYPE) , ...) | - kmalloc + kmalloc_array ( - sizeof(THING) * (E2) + E2, sizeof(THING) , ...) | - kmalloc + kmalloc_array ( - sizeof(THING) * E2 + E2, sizeof(THING) , ...) | - kmalloc + kmalloc_array ( - (E1) * E2 + E1, E2 , ...) | - kmalloc + kmalloc_array ( - (E1) * (E2) + E1, E2 , ...) | - kmalloc + kmalloc_array ( - E1 * E2 + E1, E2 , ...) ) Signed-off-by: Kees Cook <keescook@chromium.org>
2017-11-24s390/debug: use pK for kernel pointersChristian Borntraeger
the s390 debug feature (/sys/kernel/debug/s390dbf/) shows the kernel pointer of the calling function even for kptr_restrict == 2. Let us use pK instead of p. This hides the kernel addresses for kptr_restrict == 2: root@host $ echo 2 > /proc/sys/kernel/kptr_restrict root@host $ tail -n1 /sys/kernel/debug/s390dbf/cio_msg/sprintf 00 01511461280:386645 2 - 00 0000000000000000 snsid: device 0.0.3f68: rc=0 3990/e9 3390/0c root@host $ echo 1 > /proc/sys/kernel/kptr_restrict root@host $ tail -n1 /sys/kernel/debug/s390dbf/cio_msg/sprintf 00 01511461280:386645 2 - 00 000000000071171c snsid: device 0.0.3f68: rc=0 3990/e9 3390/0c root@host $ echo 0 > /proc/sys/kernel/kptr_restrict root@host $ tail -n1 /sys/kernel/debug/s390dbf/cio_msg/sprintf 00 01511461280:386645 2 - 00 000000000071171c snsid: device 0.0.3f68: rc=0 3990/e9 3390/0c Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2017-11-13Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux Pull s390 updates from Heiko Carstens: "Since Martin is on vacation you get the s390 pull request for the v4.15 merge window this time from me. Besides a lot of cleanups and bug fixes these are the most important changes: - a new regset for runtime instrumentation registers - hardware accelerated AES-GCM support for the aes_s390 module - support for the new CEX6S crypto cards - support for FORTIFY_SOURCE - addition of missing z13 and new z14 instructions to the in-kernel disassembler - generate opcode tables for the in-kernel disassembler out of a simple text file instead of having to manually maintain those tables - fast memset16, memset32 and memset64 implementations - removal of named saved segment support - hardware counter support for z14 - queued spinlocks and queued rwlocks implementations for s390 - use the stack_depth tracking feature for s390 BPF JIT - a new s390_sthyi system call which emulates the sthyi (store hypervisor information) instruction - removal of the old KVM virtio transport - an s390 specific CPU alternatives implementation which is used in the new spinlock code" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (88 commits) MAINTAINERS: add virtio-ccw.h to virtio/s390 section s390/noexec: execute kexec datamover without DAT s390: fix transactional execution control register handling s390/bpf: take advantage of stack_depth tracking s390: simplify transactional execution elf hwcap handling s390/zcrypt: Rework struct ap_qact_ap_info. s390/virtio: remove unused header file kvm_virtio.h s390: avoid undefined behaviour s390/disassembler: generate opcode tables from text file s390/disassembler: remove insn_to_mnemonic() s390/dasd: avoid calling do_gettimeofday() s390: vfio-ccw: Do not attempt to free no-op, test and tic cda. s390: remove named saved segment support s390/archrandom: Reconsider s390 arch random implementation s390/pci: do not require AIS facility s390/qdio: sanitize put_indicator s390/qdio: use atomic_cmpxchg s390/nmi: avoid using long-displacement facility s390: pass endianness info to sparse s390/decompressor: remove informational messages ...
2017-11-02License cleanup: add SPDX GPL-2.0 license identifier to files with no licenseGreg Kroah-Hartman
Many source files in the tree are missing licensing information, which makes it harder for compliance tools to determine the correct license. By default all files without license information are under the default license of the kernel, which is GPL version 2. Update the files which contain no license information with the 'GPL-2.0' SPDX license identifier. The SPDX identifier is a legally binding shorthand, which can be used instead of the full boiler plate text. This patch is based on work done by Thomas Gleixner and Kate Stewart and Philippe Ombredanne. How this work was done: Patches were generated and checked against linux-4.14-rc6 for a subset of the use cases: - file had no licensing information it it. - file was a */uapi/* one with no licensing information in it, - file was a */uapi/* one with existing licensing information, Further patches will be generated in subsequent months to fix up cases where non-standard license headers were used, and references to license had to be inferred by heuristics based on keywords. The analysis to determine which SPDX License Identifier to be applied to a file was done in a spreadsheet of side by side results from of the output of two independent scanners (ScanCode & Windriver) producing SPDX tag:value files created by Philippe Ombredanne. Philippe prepared the base worksheet, and did an initial spot review of a few 1000 files. The 4.13 kernel was the starting point of the analysis with 60,537 files assessed. Kate Stewart did a file by file comparison of the scanner results in the spreadsheet to determine which SPDX license identifier(s) to be applied to the file. She confirmed any determination that was not immediately clear with lawyers working with the Linux Foundation. Criteria used to select files for SPDX license identifier tagging was: - Files considered eligible had to be source code files. - Make and config files were included as candidates if they contained >5 lines of source - File already had some variant of a license header in it (even if <5 lines). All documentation files were explicitly excluded. The following heuristics were used to determine which SPDX license identifiers to apply. - when both scanners couldn't find any license traces, file was considered to have no license information in it, and the top level COPYING file license applied. For non */uapi/* files that summary was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 11139 and resulted in the first patch in this series. If that file was a */uapi/* path one, it was "GPL-2.0 WITH Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 WITH Linux-syscall-note 930 and resulted in the second patch in this series. - if a file had some form of licensing information in it, and was one of the */uapi/* ones, it was denoted with the Linux-syscall-note if any GPL family license was found in the file or had no licensing in it (per prior point). Results summary: SPDX license identifier # files ---------------------------------------------------|------ GPL-2.0 WITH Linux-syscall-note 270 GPL-2.0+ WITH Linux-syscall-note 169 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17 LGPL-2.1+ WITH Linux-syscall-note 15 GPL-1.0+ WITH Linux-syscall-note 14 ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5 LGPL-2.0+ WITH Linux-syscall-note 4 LGPL-2.1 WITH Linux-syscall-note 3 ((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3 ((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1 and that resulted in the third patch in this series. - when the two scanners agreed on the detected license(s), that became the concluded license(s). - when there was disagreement between the two scanners (one detected a license but the other didn't, or they both detected different licenses) a manual inspection of the file occurred. - In most cases a manual inspection of the information in the file resulted in a clear resolution of the license that should apply (and which scanner probably needed to revisit its heuristics). - When it was not immediately clear, the license identifier was confirmed with lawyers working with the Linux Foundation. - If there was any question as to the appropriate license identifier, the file was flagged for further research and to be revisited later in time. In total, over 70 hours of logged manual review was done on the spreadsheet to determine the SPDX license identifiers to apply to the source files by Kate, Philippe, Thomas and, in some cases, confirmation by lawyers working with the Linux Foundation. Kate also obtained a third independent scan of the 4.13 code base from FOSSology, and compared selected files where the other two scanners disagreed against that SPDX file, to see if there was new insights. The Windriver scanner is based on an older version of FOSSology in part, so they are related. Thomas did random spot checks in about 500 files from the spreadsheets for the uapi headers and agreed with SPDX license identifier in the files he inspected. For the non-uapi files Thomas did random spot checks in about 15000 files. In initial set of patches against 4.14-rc6, 3 files were found to have copy/paste license identifier errors, and have been fixed to reflect the correct identifier. Additionally Philippe spent 10 hours this week doing a detailed manual inspection and review of the 12,461 patched files from the initial patch version early this week with: - a full scancode scan run, collecting the matched texts, detected license ids and scores - reviewing anything where there was a license detected (about 500+ files) to ensure that the applied SPDX license was correct - reviewing anything where there was no detection but the patch license was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied SPDX license was correct This produced a worksheet with 20 files needing minor correction. This worksheet was then exported into 3 different .csv files for the different types of files to be modified. These .csv files were then reviewed by Greg. Thomas wrote a script to parse the csv files and add the proper SPDX tag to the file, in the format that the file expected. This script was further refined by Greg based on the output to detect more types of files automatically and to distinguish between header and source .c files (which need different comment types.) Finally Greg ran the script using the .csv files to generate the patches. Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-10-18s390/debug: only write data onceSebastian Ott
debug_event_common memsets the active debug entry with zeros to prevent stale data leakage. This is overwritten with the actual debug data in the next step. Only write zeros to that part of the debug entry that's not used by new debug data. Micro benchmarks show a 2-10% reduction of cpu cycles with this approach. Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com> Acked-by: Michael Holzheu <holzheu@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>