mirror of https://github.com/torvalds/linux.git
79357cd06d
kasan_populate_vmalloc() and its helpers ignore the caller's gfp_mask and
always allocate memory using the hardcoded GFP_KERNEL flag. This makes
them inconsistent with vmalloc(), which was recently extended to support
GFP_NOFS and GFP_NOIO allocations.
Page table allocations performed during shadow population also ignore the
external gfp_mask. To preserve the intended semantics of GFP_NOFS and
GFP_NOIO, wrap the apply_to_page_range() calls into the appropriate
memalloc scope.
xfs calls vmalloc with GFP_NOFS, so this bug could lead to deadlock.
There was a report here
https://lkml.kernel.org/r/686ea951.050a0220.385921.0016.GAE@google.com
This patch:
- Extends kasan_populate_vmalloc() and helpers to take gfp_mask;
- Passes gfp_mask down to alloc_pages_bulk() and __get_free_page();
- Enforces GFP_NOFS/NOIO semantics with memalloc_*_save()/restore()
around apply_to_page_range();
- Updates vmalloc.c and percpu allocator call sites accordingly.
Link: https://lkml.kernel.org/r/20250831121058.92971-1-urezki@gmail.com
Fixes:
|
||
|---|---|---|
| .. | ||
| Makefile | ||
| common.c | ||
| generic.c | ||
| hw_tags.c | ||
| init.c | ||
| kasan.h | ||
| kasan_test_c.c | ||
| kasan_test_rust.rs | ||
| quarantine.c | ||
| report.c | ||
| report_generic.c | ||
| report_hw_tags.c | ||
| report_sw_tags.c | ||
| report_tags.c | ||
| shadow.c | ||
| sw_tags.c | ||
| tags.c | ||