diff options
| author | Jia Zhang <zhang.jia@linux.alibaba.com> | 2018-02-12 17:44:53 +0300 |
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2018-02-13 11:15:58 +0300 |
| commit | 595dd46ebfc10be041a365d0a3fa99df50b6ba73 (patch) | |
| tree | 3e781a635cad1504225e1753289d7ffecb1d8a6f /arch | |
| parent | aec6487e994d2f625197970a56a4aac40c2c7547 (diff) | |
| download | linux-595dd46ebfc10be041a365d0a3fa99df50b6ba73.tar.xz | |
vfs/proc/kcore, x86/mm/kcore: Fix SMAP fault when dumping vsyscall user page
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>
Diffstat (limited to 'arch')
| -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 1ab42c852069..6aa33d1e198f 100644 --- a/arch/x86/mm/init_64.c +++ b/arch/x86/mm/init_64.c @@ -1193,8 +1193,7 @@ void __init mem_init(void) register_page_bootmem_info(); /* 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); } |