When CONFIG_CMDLINE_BOOL is enabled without CONFIG_CMDLINE_OVERRIDE, setup_arch() appends boot_command_line to builtin_cmdline using two strlcat() calls before copying the result back to boot_command_line.
In preparation for removing the deprecated strlcat() API[1], format the combined command line into a temporary buffer using a single snprintf() call and copy the result to both builtin_cmdline and boot_command_line. Using a temporary buffer avoids undefined behavior from passing overlapping source and destination buffers to snprintf(). Link: https://github.com/KSPP/linux/issues/370 [1] Cc: [email protected] Assisted-by: Developer:Gemini_2.5_Pro [editor_update_file, make_kernel_build_single_file, checkpatch_run] Signed-off-by: Bill Wendling <[email protected]> --- Cc: Russell King <[email protected]> Cc: Huacai Chen <[email protected]> Cc: WANG Xuerui <[email protected]> Cc: Thomas Bogendoerfer <[email protected]> Cc: "James E.J. Bottomley" <[email protected]> Cc: Helge Deller <[email protected]> Cc: Thomas Gleixner <[email protected]> Cc: Ingo Molnar <[email protected]> Cc: Borislav Petkov <[email protected]> Cc: Dave Hansen <[email protected]> Cc: [email protected] Cc: "H. Peter Anvin" <[email protected]> Cc: Ian Abbott <[email protected]> Cc: H Hartley Sweeten <[email protected]> Cc: Tony Luck <[email protected]> Cc: Maarten Lankhorst <[email protected]> Cc: Maxime Ripard <[email protected]> Cc: Thomas Zimmermann <[email protected]> Cc: David Airlie <[email protected]> Cc: Simona Vetter <[email protected]> Cc: Matthew Brost <[email protected]> Cc: "Thomas Hellström" <[email protected]> Cc: Rodrigo Vivi <[email protected]> Cc: Dmitry Torokhov <[email protected]> Cc: Matthias Schwarzott <[email protected]> Cc: Mauro Carvalho Chehab <[email protected]> Cc: Tony Nguyen <[email protected]> Cc: Przemek Kitszel <[email protected]> Cc: Andrew Lunn <[email protected]> Cc: "David S. Miller" <[email protected]> Cc: Eric Dumazet <[email protected]> Cc: Jakub Kicinski <[email protected]> Cc: Paolo Abeni <[email protected]> Cc: Arend van Spriel <[email protected]> Cc: Rob Herring <[email protected]> Cc: Saravana Kannan <[email protected]> Cc: Krzysztof Kozlowski <[email protected]> Cc: Sylwester Nawrocki <[email protected]> Cc: Peter Griffin <[email protected]> Cc: Alim Akhtar <[email protected]> Cc: Linus Walleij <[email protected]> Cc: Anil Gurumurthy <[email protected]> Cc: Sudarsana Kalluru <[email protected]> Cc: "Martin K. Petersen" <[email protected]> Cc: Trond Myklebust <[email protected]> Cc: Anna Schumaker <[email protected]> Cc: Mike Marshall <[email protected]> Cc: Martin Brandenburg <[email protected]> Cc: Kees Cook <[email protected]> Cc: Jiri Pirko <[email protected]> Cc: Simon Horman <[email protected]> Cc: Chuck Lever <[email protected]> Cc: Jeff Layton <[email protected]> Cc: NeilBrown <[email protected]> Cc: Olga Kornievskaia <[email protected]> Cc: Dai Ngo <[email protected]> Cc: Tom Talpey <[email protected]> Cc: Jaroslav Kysela <[email protected]> Cc: Takashi Iwai <[email protected]> Cc: Bill Wendling <[email protected]> Cc: Andrew Morton <[email protected]> Cc: "Mike Rapoport (Microsoft)" <[email protected]> Cc: Kanglong Wang <[email protected]> Cc: Tiezhu Yang <[email protected]> Cc: Qiang Ma <[email protected]> Cc: Randy Dunlap <[email protected]> Cc: Pengpeng Hou <[email protected]> Cc: Ard Biesheuvel <[email protected]> Cc: Breno Leitao <[email protected]> Cc: Thorsten Blum <[email protected]> Cc: Harshit Mogalapalli <[email protected]> Cc: Greg Kroah-Hartman <[email protected]> Cc: Lyude Paul <[email protected]> Cc: Ashutosh Desai <[email protected]> Cc: Imre Deak <[email protected]> Cc: Dmitry Baryshkov <[email protected]> Cc: Johan Hovold <[email protected]> Cc: Johannes Berg <[email protected]> Cc: Miri Korenblit <[email protected]> Cc: Alexander Stein <[email protected]> Cc: Cryolitia PukNgae <[email protected]> Cc: Jiaming Zhang <[email protected]> Cc: Will Porter <[email protected]> Cc: Cen Zhang <[email protected]> Cc: "Cássio Gabriel" <[email protected]> Cc: Rong Zhang <[email protected]> Cc: Arun Raghavan <[email protected]> Cc: [email protected] Cc: [email protected] Cc: [email protected] Cc: [email protected] Cc: [email protected] Cc: [email protected] Cc: [email protected] Cc: [email protected] Cc: [email protected] Cc: [email protected] Cc: [email protected] Cc: [email protected] Cc: [email protected] Cc: [email protected] Cc: [email protected] Cc: [email protected] Cc: [email protected] Cc: [email protected] Cc: [email protected] Cc: [email protected] Cc: [email protected] Cc: [email protected] Cc: [email protected] --- arch/x86/kernel/setup.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c index cda6adb9f69c..c40e0edd7c13 100644 --- a/arch/x86/kernel/setup.c +++ b/arch/x86/kernel/setup.c @@ -916,9 +916,11 @@ void __init setup_arch(char **cmdline_p) #else if (builtin_cmdline[0]) { /* append boot loader cmdline to builtin */ - strlcat(builtin_cmdline, " ", COMMAND_LINE_SIZE); - strlcat(builtin_cmdline, boot_command_line, COMMAND_LINE_SIZE); - strscpy(boot_command_line, builtin_cmdline, COMMAND_LINE_SIZE); + char tmp[COMMAND_LINE_SIZE]; + + snprintf(tmp, COMMAND_LINE_SIZE, "%s %s", builtin_cmdline, boot_command_line); + strscpy(builtin_cmdline, tmp, COMMAND_LINE_SIZE); + strscpy(boot_command_line, tmp, COMMAND_LINE_SIZE); } #endif builtin_cmdline_added = true; -- 2.55.0.1032.g73a4cd73de-goog
