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X-Spam-Score: -0.2 (/) X-Spam-Report: SpamAssassin version 3.4.2 on bombadil.infradead.org summary: Content analysis details: (-0.2 points) pts rule name description ---- ---------------------- -------------------------------------------------- -0.0 RCVD_IN_DNSWL_NONE RBL: Sender listed at https://www.dnswl.org/, no trust [216.200.240.184 listed in list.dnswl.org] -0.0 SPF_PASS SPF: sender matches SPF record 0.0 SPF_HELO_NONE SPF: HELO does not publish an SPF Record 0.0 MIME_BASE64_TEXT RAW: Message text disguised using base64 encoding -0.1 DKIM_VALID Message has at least one valid DKIM or DK signature -0.1 DKIM_VALID_EF Message has a valid DKIM or DK signature from envelope-from domain -0.1 DKIM_VALID_AU Message has a valid DKIM or DK signature from author's domain 0.1 DKIM_SIGNED Message has a DKIM or DK signature, not necessarily valid 0.0 UNPARSEABLE_RELAY Informational: message has unparseable relay lines X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: kstewart@linuxfoundation.org, mike-sl.lin@mediatek.com, alix.wu@mediatek.com, eddy.lin@mediatek.com, gregkh@linuxfoundation.org, yj.chiang@mediatek.com, phil.chang@mediatek.com, linux-kernel@vger.kernel.org, linux-mediatek@lists.infradead.org, linux-arm-kernel@lists.infradead.org, mark-pk.tsai@mediatek.com, matthias.bgg@gmail.com, tglx@linutronix.de, info@metux.net, lvqiang.huang@unisoc.com, allison@lohutok.net Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org The sv_pc, which is saved in the stack, may be an invalid address if the target thread is running on another processor in the meantime. It will cause kernel crash at `ldr r2, [sv_pc, #-4]`. Check if sv_pc is valid before use it like unwind_frame in arch/arm/kernel/unwind.c. Signed-off-by: Mike-SL Lin Signed-off-by: Mark-PK Tsai --- arch/arm/lib/backtrace.S | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/arch/arm/lib/backtrace.S b/arch/arm/lib/backtrace.S index 582925238d65..84f06381bbfb 100644 --- a/arch/arm/lib/backtrace.S +++ b/arch/arm/lib/backtrace.S @@ -64,6 +64,11 @@ for_each_frame: tst frame, mask @ Check for address exceptions sub sv_pc, sv_pc, offset @ Correct PC for prefetching bic sv_pc, sv_pc, mask @ mask PC/LR for the mode + mov r0, sv_pc + bl kernel_text_address @ check if sv_pc is valid + cmp r0, #0 @ if sv_pc is not kernel text + beq 1006f @ address, abort backtrace + 1003: ldr r2, [sv_pc, #-4] @ if stmfd sp!, {args} exists, ldr r3, .Ldsi+4 @ adjust saved 'pc' back one teq r3, r2, lsr #11 @ instruction