diff options
| author | Jia Zhang <zhang.jia@linux.alibaba.com> | 2018-02-12 22:44:53 +0800 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2018-04-26 11:02:20 +0200 |
| commit | f4d6e4598a29f6f7df6937d943c01e1eeb9ee871 (patch) | |
| tree | 4205cfc14a57931f467c59a75b8c07dc7cf83de5 /arch/x86/mm/init_64.c | |
| parent | c064b7c1d203cd5d781c316ac9c8049ba772684f (diff) | |
vfs/proc/kcore, x86/mm/kcore: Fix SMAP fault when dumping vsyscall user page
[ Upstream commit 595dd46ebfc10be041a365d0a3fa99df50b6ba73 ]
Commit:
df04abfd181a ("fs/proc/kcore.c: Add bounce buffer for ktext data")
... introduced a bounce buffer to work around CONFIG_HARDENED_USERCOPY=y.
However, accessing the vsyscall user page will cause an SMAP fault.
Replace memcpy() with copy_from_user() to fix this bug works, but adding
a common way to handle this sort of user page may be useful for future.
Currently, only vsyscall page requires KCORE_USER.
Signed-off-by: Jia Zhang <zhang.jia@linux.alibaba.com>
Reviewed-by: Jiri Olsa <jolsa@kernel.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: jolsa@redhat.com
Link: http://lkml.kernel.org/r/1518446694-21124-2-git-send-email-zhang.jia@linux.alibaba.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'arch/x86/mm/init_64.c')
| -rw-r--r-- | arch/x86/mm/init_64.c | 3 |
1 files changed, 1 insertions, 2 deletions
diff --git a/arch/x86/mm/init_64.c b/arch/x86/mm/init_64.c index fe85d1204db8..642357aff216 100644 --- a/arch/x86/mm/init_64.c +++ b/arch/x86/mm/init_64.c @@ -1180,8 +1180,7 @@ void __init mem_init(void) after_bootmem = 1; /* Register memory areas for /proc/kcore */ - kclist_add(&kcore_vsyscall, (void *)VSYSCALL_ADDR, - PAGE_SIZE, KCORE_OTHER); + kclist_add(&kcore_vsyscall, (void *)VSYSCALL_ADDR, PAGE_SIZE, KCORE_USER); mem_init_print_info(NULL); } |