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Bottomley" , Helge Deller , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , x86@kernel.org, "H. Peter Anvin" , Ian Abbott , H Hartley Sweeten , Tony Luck , Maarten Lankhorst , Maxime Ripard , Thomas Zimmermann , David Airlie , Simona Vetter , Matthew Brost , "=?UTF-8?q?Thomas=20Hellstr=C3=B6m?=" , Rodrigo Vivi , Dmitry Torokhov , Matthias Schwarzott , Mauro Carvalho Chehab , Tony Nguyen , Przemek Kitszel , Andrew Lunn , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Arend van Spriel , Rob Herring , Saravana Kannan , Krzysztof Kozlowski , Sylwester Nawrocki , Peter Griffin , Alim Akhtar , Linus Walleij , Anil Gurumurthy , Sudarsana Kalluru , "Martin K. Petersen" , Trond Myklebust , Anna Schumaker , Mike Marshall , Martin Brandenburg , Kees Cook , Jiri Pirko , Simon Horman , Chuck Lever , Jeff Layton , NeilBrown , Olga Kornievskaia , Dai Ngo , Tom Talpey , Jaroslav Kysela , Takashi Iwai , Andrew Morton , "Mike Rapoport (Microsoft)" , Kanglong Wang , Tiezhu Yang , Qiang Ma , Randy Dunlap , Pengpeng Hou , Ard Biesheuvel , Breno Leitao , Thorsten Blum , Harshit Mogalapalli , Greg Kroah-Hartman , Lyude Paul , Ashutosh Desai , Imre Deak , Dmitry Baryshkov , Johan Hovold , Johannes Berg , Miri Korenblit , Alexander Stein , Cryolitia PukNgae , Jiaming Zhang , Will Porter , Cen Zhang , "=?UTF-8?q?C=C3=A1ssio=20Gabriel?=" , Rong Zhang , Arun Raghavan , linux-arm-kernel@lists.infradead.org, loongarch@lists.linux.dev, linux-mips@vger.kernel.org, linux-parisc@vger.kernel.org, linux-edac@vger.kernel.org, dri-devel@lists.freedesktop.org, intel-xe@lists.freedesktop.org, linux-input@vger.kernel.org, linux-media@vger.kernel.org, intel-wired-lan@lists.osuosl.org, netdev@vger.kernel.org, linux-wireless@vger.kernel.org, brcm80211@lists.linux.dev, brcm80211-dev-list.pdl@broadcom.com, devicetree@vger.kernel.org, linux-samsung-soc@vger.kernel.org, linux-gpio@vger.kernel.org, linux-scsi@vger.kernel.org, linux-nfs@vger.kernel.org, devel@lists.orangefs.org, linux-hardening@vger.kernel.org, linux-sound@vger.kernel.org Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable bootcmdline_append() passes "max" (the maximum length of the source string "s") as the destination buffer size argument to strlcat(). Because strlcat() expects the total size of the destination buffer (COMMAND_LINE_SIZE), it fails to append anything whenever "max" is smaller than the current length of boot_command_line, and could overflow boot_command_line if "max" exceeds COMMAND_LINE_SIZE. In preparation for removing the deprecated strlcat() API[1], replace the strlcat() calls with snprintf() using the "%.*s" precision specifier. This bounds the read from "s" to at most "max" bytes while properly respecting the remaining space in boot_command_line. Link: https://github.com/KSPP/linux/issues/370 [1] Cc: codemender-patching+linux@google.com Assisted-by: SecurityEngineer:Gemini2.5Pro [editor_update_file, shell_comma= nd_run, make_kernel_build_single_file, test_runner_run_kunit_test] Signed-off-by: Bill Wendling --- Cc: Russell King Cc: Huacai Chen Cc: WANG Xuerui Cc: Thomas Bogendoerfer Cc: "James E.J. Bottomley" Cc: Helge Deller Cc: Thomas Gleixner Cc: Ingo Molnar Cc: Borislav Petkov Cc: Dave Hansen Cc: x86@kernel.org Cc: "H. Peter Anvin" Cc: Ian Abbott Cc: H Hartley Sweeten Cc: Tony Luck Cc: Maarten Lankhorst Cc: Maxime Ripard Cc: Thomas Zimmermann Cc: David Airlie Cc: Simona Vetter Cc: Matthew Brost Cc: "Thomas Hellstr=C3=B6m" Cc: Rodrigo Vivi Cc: Dmitry Torokhov Cc: Matthias Schwarzott Cc: Mauro Carvalho Chehab Cc: Tony Nguyen Cc: Przemek Kitszel Cc: Andrew Lunn Cc: "David S. Miller" Cc: Eric Dumazet Cc: Jakub Kicinski Cc: Paolo Abeni Cc: Arend van Spriel Cc: Rob Herring Cc: Saravana Kannan Cc: Krzysztof Kozlowski Cc: Sylwester Nawrocki Cc: Peter Griffin Cc: Alim Akhtar Cc: Linus Walleij Cc: Anil Gurumurthy Cc: Sudarsana Kalluru Cc: "Martin K. Petersen" Cc: Trond Myklebust Cc: Anna Schumaker Cc: Mike Marshall Cc: Martin Brandenburg Cc: Kees Cook Cc: Jiri Pirko Cc: Simon Horman Cc: Chuck Lever Cc: Jeff Layton Cc: NeilBrown Cc: Olga Kornievskaia Cc: Dai Ngo Cc: Tom Talpey Cc: Jaroslav Kysela Cc: Takashi Iwai Cc: Bill Wendling Cc: Andrew Morton Cc: "Mike Rapoport (Microsoft)" Cc: Kanglong Wang Cc: Tiezhu Yang Cc: Qiang Ma Cc: Randy Dunlap Cc: Pengpeng Hou Cc: Ard Biesheuvel Cc: Breno Leitao Cc: Thorsten Blum Cc: Harshit Mogalapalli Cc: Greg Kroah-Hartman Cc: Lyude Paul Cc: Ashutosh Desai Cc: Imre Deak Cc: Dmitry Baryshkov Cc: Johan Hovold Cc: Johannes Berg Cc: Miri Korenblit Cc: Alexander Stein Cc: Cryolitia PukNgae Cc: Jiaming Zhang Cc: Will Porter Cc: Cen Zhang Cc: "C=C3=A1ssio Gabriel" Cc: Rong Zhang Cc: Arun Raghavan Cc: linux-arm-kernel@lists.infradead.org Cc: linux-kernel@vger.kernel.org Cc: loongarch@lists.linux.dev Cc: linux-mips@vger.kernel.org Cc: linux-parisc@vger.kernel.org Cc: linux-edac@vger.kernel.org Cc: dri-devel@lists.freedesktop.org Cc: intel-xe@lists.freedesktop.org Cc: linux-input@vger.kernel.org Cc: linux-media@vger.kernel.org Cc: intel-wired-lan@lists.osuosl.org Cc: netdev@vger.kernel.org Cc: linux-wireless@vger.kernel.org Cc: brcm80211@lists.linux.dev Cc: brcm80211-dev-list.pdl@broadcom.com Cc: devicetree@vger.kernel.org Cc: linux-samsung-soc@vger.kernel.org Cc: linux-gpio@vger.kernel.org Cc: linux-scsi@vger.kernel.org Cc: linux-nfs@vger.kernel.org Cc: devel@lists.orangefs.org Cc: linux-hardening@vger.kernel.org Cc: linux-sound@vger.kernel.org --- arch/mips/kernel/setup.c | 21 ++++++++++++++++++--- 1 file changed, 18 insertions(+), 3 deletions(-) diff --git a/arch/mips/kernel/setup.c b/arch/mips/kernel/setup.c index 1ae6d0c0e1d6..0d9c2137d675 100644 --- a/arch/mips/kernel/setup.c +++ b/arch/mips/kernel/setup.c @@ -518,13 +518,28 @@ static void __init check_kernel_sections_mem(void) =20 static void __init bootcmdline_append(const char *s, size_t max) { + size_t len; + int prec; + if (!s[0] || !max) return; =20 - if (boot_command_line[0]) - strlcat(boot_command_line, " ", COMMAND_LINE_SIZE); + len =3D strlen(boot_command_line); + if (len >=3D COMMAND_LINE_SIZE - 1) + return; =20 - strlcat(boot_command_line, s, max); + if (len) { + if (COMMAND_LINE_SIZE - len < 3) + return; + + prec =3D min_t(size_t, max, COMMAND_LINE_SIZE - len - 2); + snprintf(boot_command_line + len, COMMAND_LINE_SIZE - len, " %.*s", + prec, s); + } else { + prec =3D min_t(size_t, max, COMMAND_LINE_SIZE - 1); + snprintf(boot_command_line, COMMAND_LINE_SIZE, "%.*s", + prec, s); + } } =20 #ifdef CONFIG_OF_EARLY_FLATTREE --=20 2.55.0.1032.g73a4cd73de-goog