path: root/kernel/stacktrace.c
diff options
authorChristoph Hellwig <hch@lst.de>2020-08-11 18:33:47 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2020-08-12 10:57:59 -0700
commit3d13f313ce4c34c524ccc37986fe77172f601ff3 (patch)
treefd71a87be80c03601ab0e3be425fe45da116b5ba /kernel/stacktrace.c
parent428e2976a5bf7e7f5554286d7a5a33b8147b106a (diff)
uaccess: add force_uaccess_{begin,end} helpers
Add helpers to wrap the get_fs/set_fs magic for undoing any damange done by set_fs(KERNEL_DS). There is no real functional benefit, but this documents the intent of these calls better, and will allow stubbing the functions out easily for kernels builds that do not allow address space overrides in the future. [hch@lst.de: drop two incorrect hunks, fix a commit log typo] Link: http://lkml.kernel.org/r/20200714105505.935079-6-hch@lst.de Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Mark Rutland <mark.rutland@arm.com> Acked-by: Greentime Hu <green.hu@gmail.com> Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Nick Hu <nickhu@andestech.com> Cc: Vincent Chen <deanbo422@gmail.com> Cc: Paul Walmsley <paul.walmsley@sifive.com> Cc: Palmer Dabbelt <palmer@dabbelt.com> Link: http://lkml.kernel.org/r/20200710135706.537715-6-hch@lst.de Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'kernel/stacktrace.c')
1 files changed, 2 insertions, 3 deletions
diff --git a/kernel/stacktrace.c b/kernel/stacktrace.c
index 2af66e449aa6..946f44a9e86a 100644
--- a/kernel/stacktrace.c
+++ b/kernel/stacktrace.c
@@ -233,10 +233,9 @@ unsigned int stack_trace_save_user(unsigned long *store, unsigned int size)
if (current->flags & PF_KTHREAD)
return 0;
- fs = get_fs();
- set_fs(USER_DS);
+ fs = force_uaccess_begin();
arch_stack_walk_user(consume_entry, &c, task_pt_regs(current));
- set_fs(fs);
+ force_uaccess_end(fs);
return c.len;

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