From 3db5fc556515e4676ee89f6736e0cf0c3e3c6072 Mon Sep 17 00:00:00 2001 From: Pavel Tatashin Date: Fri, 19 Mar 2021 16:50:54 -0400 Subject: [PATCH] arm64: kdump: update ppos when reading elfcorehdr [ Upstream commit 141f8202cfa4192c3af79b6cbd68e7760bb01b5a ] The ppos points to a position in the old kernel memory (and in case of arm64 in the crash kernel since elfcorehdr is passed as a segment). The function should update the ppos by the amount that was read. This bug is not exposed by accident, but other platforms update this value properly. So, fix it in ARM64 version of elfcorehdr_read() as well. Signed-off-by: Pavel Tatashin Fixes: e62aaeac426a ("arm64: kdump: provide /proc/vmcore file") Reviewed-by: Tyler Hicks Link: https://lore.kernel.org/r/20210319205054.743368-1-pasha.tatashin@soleen.com Signed-off-by: Will Deacon Signed-off-by: Sasha Levin --- arch/arm64/kernel/crash_dump.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/arch/arm64/kernel/crash_dump.c b/arch/arm64/kernel/crash_dump.c index e6e2842..58303a9 100644 --- a/arch/arm64/kernel/crash_dump.c +++ b/arch/arm64/kernel/crash_dump.c @@ -64,5 +64,7 @@ ssize_t copy_oldmem_page(unsigned long pfn, char *buf, ssize_t elfcorehdr_read(char *buf, size_t count, u64 *ppos) { memcpy(buf, phys_to_virt((phys_addr_t)*ppos), count); + *ppos += count; + return count; } -- 2.7.4