diff options
| author | Christoph Hellwig <hch@lst.de> | 2020-07-20 14:44:48 +0300 |
|---|---|---|
| committer | Greentime Hu <green.hu@gmail.com> | 2021-02-25 09:31:49 +0300 |
| commit | fa2f478a348efa483abd4159c9f5478a3867bcc0 (patch) | |
| tree | 47b069b6b4e341d94e8613add84dcc5af198cc11 /arch/nds32 | |
| parent | 9d63fecfcb2c7d379b6dd06892c534068a03a470 (diff) | |
| download | linux-fa2f478a348efa483abd4159c9f5478a3867bcc0.tar.xz | |
nds32: use get_kernel_nofault in dump_mem
Use the proper get_kernel_nofault helper to access an unsafe kernel
pointer without faulting instead of playing with set_fs and get_user.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Nick Hu <nickhu@andestech.com>
Acked-by: Greentime Hu <green.hu@gmail.com>
Signed-off-by: Greentime Hu <green.hu@gmail.com>
Diffstat (limited to 'arch/nds32')
| -rw-r--r-- | arch/nds32/kernel/traps.c | 15 |
1 files changed, 3 insertions, 12 deletions
diff --git a/arch/nds32/kernel/traps.c b/arch/nds32/kernel/traps.c index b66f889bc6df..ee0d9ae192a5 100644 --- a/arch/nds32/kernel/traps.c +++ b/arch/nds32/kernel/traps.c @@ -25,17 +25,8 @@ extern void show_pte(struct mm_struct *mm, unsigned long addr); void dump_mem(const char *lvl, unsigned long bottom, unsigned long top) { unsigned long first; - mm_segment_t fs; int i; - /* - * We need to switch to kernel mode so that we can use __get_user - * to safely read from kernel space. Note that we now dump the - * code first, just in case the backtrace kills us. - */ - fs = get_fs(); - set_fs(KERNEL_DS); - pr_emerg("%s(0x%08lx to 0x%08lx)\n", lvl, bottom, top); for (first = bottom & ~31; first < top; first += 32) { @@ -48,7 +39,9 @@ void dump_mem(const char *lvl, unsigned long bottom, unsigned long top) for (p = first, i = 0; i < 8 && p < top; i++, p += 4) { if (p >= bottom && p < top) { unsigned long val; - if (__get_user(val, (unsigned long *)p) == 0) + + if (get_kernel_nofault(val, + (unsigned long *)p) == 0) sprintf(str + i * 9, " %08lx", val); else sprintf(str + i * 9, " ????????"); @@ -56,8 +49,6 @@ void dump_mem(const char *lvl, unsigned long bottom, unsigned long top) } pr_emerg("%s%04lx:%s\n", lvl, first & 0xffff, str); } - - set_fs(fs); } EXPORT_SYMBOL(dump_mem); |