linux.git/kernel/debug/kdb/kdb_main.c, branch v6.18.21

kdb: Replace deprecated strcpy() with helper function in kdb_defcmd()

2025-09-20T18:56:28+00:00

strcpy() is deprecated; use the new helper function kdb_strdup_dequote()
instead. In addition to string duplication similar to kdb_strdup(), it
also trims surrounding quotes from the input string if present.

kdb_strdup_dequote() also checks for a trailing quote in the input
string which was previously not checked.

Link: https://github.com/KSPP/linux/issues/88
Reviewed-by: Douglas Anderson 
Signed-off-by: Thorsten Blum 
Signed-off-by: Daniel Thompson (RISCstar)

kdb: Replace deprecated strcpy() with memcpy() in parse_grep()

2025-09-20T18:56:28+00:00

strcpy() is deprecated; use memcpy() instead.

We can safely use memcpy() because we already know the length of the
source string 'cp' and that it is guaranteed to be NUL-terminated within
the first KDB_GREP_STRLEN bytes.

Link: https://github.com/KSPP/linux/issues/88
Reviewed-by: Douglas Anderson 
Signed-off-by: Thorsten Blum 
Signed-off-by: Daniel Thompson (RISCstar)

Merge tag 'tty-6.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty

2025-04-03T01:17:33+00:00

Pull tty/serial driver updates from Greg KH:
 "Here is the big set of serial and tty driver updates for 6.15-rc1.
  Include in here are the following:

   - more great tty layer cleanups from Jiri. Someday this will be done,
     but that's not going to be any year soon...

   - kdb debug driver reverts to fix a reported issue

   - lots of .dts binding updates for different devices with serial
     devices

   - lots of tiny updates and tweaks and a few bugfixes for different
     serial drivers.

  All of these have been in linux-next for a while with no reported
  issues"

* tag 'tty-6.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (79 commits)
  tty: serial: fsl_lpuart: Fix unused variable 'sport' build warning
  serial: stm32: do not deassert RS485 RTS GPIO prematurely
  serial: 8250: add driver for NI UARTs
  dt-bindings: serial: snps-dw-apb-uart: document RZ/N1 binding without DMA
  serial: icom: fix code format problems
  serial: sh-sci: Save and restore more registers
  tty: serial: pl011: remove incorrect of_match_ptr annotation
  dt-bindings: serial: snps-dw-apb-uart: Add support for rk3562
  tty: serial: lpuart: only disable CTS instead of overwriting the whole UARTMODIR register
  tty: caif: removed unused function debugfs_tx()
  serial: 8250_dma: terminate correct DMA in tx_dma_flush()
  tty: serial: fsl_lpuart: rename register variables more specifically
  tty: serial: fsl_lpuart: use port struct directly to simply code
  tty: serial: fsl_lpuart: Use u32 and u8 for register variables
  tty: serial: fsl_lpuart: disable transmitter before changing RS485 related registers
  tty: serial: 8250: Add Brainboxes XC devices
  dt-bindings: serial: fsl-lpuart: support i.MX94
  tty: serial: 8250: Add some more device IDs
  dt-bindings: serial: samsung: add exynos7870-uart compatible
  serial: 8250_dw: Comment possible corner cases in serial_out() implementation
  ...

kdb: remove usage of static environment buffer

2025-03-28T21:10:53+00:00

Problem: The set environment variable logic uses a static "heap" like
buffer to store the values of the variables, and they are never freed,
on top of that this is redundant since the kernel supplies allocation
facilities which are even used also in this file.

Solution: Remove the weird static buffer logic and use kmalloc instead,
call kfree when overriding an existing variable.

Signed-off-by: Nir Lichtman 
Reviewed-by: Douglas Anderson 
Link: https://lore.kernel.org/r/20250204054741.GB1219827@lichtman.org
Signed-off-by: Daniel Thompson

Revert "kdb: Implement disable_nmi command"

2025-02-14T09:05:43+00:00

This reverts commit ad394f66fa57ae66014cb74f337e2820bac4c417.

No architectures ever implemented `enable_nmi` since the later patches
in the series adding it never landed. It's been a long time. Drop it.

NOTE: this is not a clean revert due to changes in the file in the
meantime.

Signed-off-by: Douglas Anderson 
Link: https://lore.kernel.org/r/20250129082535.2.Ib91bfb95bdcf77591257a84063fdeb5b4dce65b1@changeid
Signed-off-by: Greg Kroah-Hartman

kdb: Remove fallback interpretation of arbitrary numbers as hex

2024-11-02T08:33:13+00:00

Remove logic that enables a fallback of interpreting numbers supplied in KDB CLI
to be interpreted as hex without explicit "0x" prefix as this can be confusing
for the end users.

Suggested-by: Douglas Anderson 
Reviewed-by: Douglas Anderson 
Signed-off-by: Nir Lichtman 
Link: https://lore.kernel.org/r/20241028192228.GC918454@lichtman.org
Signed-off-by: Daniel Thompson

kdb: Replace the use of simple_strto with safer kstrto in kdb_main

2024-11-02T08:33:13+00:00

The simple_str* family of functions perform no error checking in
scenarios where the input value overflows the intended output variable.
This results in these functions successfully returning even when the
output does not match the input string.

Or as it was mentioned [1], "...simple_strtol(), simple_strtoll(),
simple_strtoul(), and simple_strtoull() functions explicitly ignore
overflows, which may lead to unexpected results in callers."
Hence, the use of those functions is discouraged.

This patch replaces all uses of the simple_strto* series of functions
with their safer kstrto* alternatives.

Side effects of this patch:
- Every string to long or long long conversion using kstrto* is now
  checked for failure.
- kstrto* errors are handled with appropriate `KDB_BADINT` wherever
  applicable.
- A good side effect is that we end up saving a few lines of code
  since unlike in simple_strto* functions, kstrto functions do not
  need an additional "end pointer" variable, and the return values
  of the latter can be directly checked in an "if" statement without
  the need to define additional `ret` or `err` variables.
  This, of course, results in cleaner, yet still easy to understand
  code.

[1] https://www.kernel.org/doc/html/latest/process/deprecated.html#simple-strtol-simple-strtoll-simple-strtoul-simple-strtoull

Signed-off-by: Yuran Pereira 
[nir: addressed review comments by fixing styling, invalid conversion and a missing error return]
Signed-off-by: Nir Lichtman 
Reviewed-by: Douglas Anderson 
Link: https://lore.kernel.org/r/20241028191916.GA918454@lichtman.org
Signed-off-by: Daniel Thompson

kdb: Get rid of redundant kdb_curr_task()

2024-06-21T14:49:29+00:00

Commit cf8e8658100d ("arch: Remove Itanium (IA-64) architecture")
removed the only definition of macro _TIF_MCA_INIT, so kdb_curr_task()
is actually the same as curr_task() now and becomes redundant.

Let's remove the definition of kdb_curr_task() and replace remaining
calls with curr_task().

Signed-off-by: Zheng Zengkai 
Reviewed-by: Douglas Anderson 
Link: https://lore.kernel.org/r/20240620142132.157518-1-zhengzengkai@huawei.com
Signed-off-by: Daniel Thompson

kdb: Use str_plural() to fix Coccinelle warning

2024-04-22T15:53:19+00:00

Fixes the following Coccinelle/coccicheck warning reported by
string_choices.cocci:

	opportunity for str_plural(days)

Signed-off-by: Thorsten Blum 
Reviewed-by: Douglas Anderson 
Link: https://lore.kernel.org/r/20240328140015.388654-3-thorsten.blum@toblux.com
Signed-off-by: Daniel Thompson

kdb: Fix a potential buffer overflow in kdb_local()

2024-01-17T17:19:06+00:00

When appending "[defcmd]" to 'kdb_prompt_str', the size of the string
already in the buffer should be taken into account.

An option could be to switch from strncat() to strlcat() which does the
correct test to avoid such an overflow.

However, this actually looks as dead code, because 'defcmd_in_progress'
can't be true here.
See a more detailed explanation at [1].

[1]: https://lore.kernel.org/all/CAD=FV=WSh7wKN7Yp-3wWiDgX4E3isQ8uh0LCzTmd1v9Cg9j+nQ@mail.gmail.com/

Fixes: 5d5314d6795f ("kdb: core for kgdb back end (1 of 2)")
Signed-off-by: Christophe JAILLET 
Reviewed-by: Douglas Anderson