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charset=utf-8 Content-Transfer-Encoding: quoted-printable X-ZohoMailClient: External On 19 March 2026 15:57:38 GMT, Josh Law wrote: >This series fixes a memory leak and three NULL pointer dereferences in >the DAMON sysfs interface, all in mm/damon/sysfs=2Ec=2E > >Patch 1 fixes a damon_ctx leak in damon_sysfs_commit_input() when >damon_sysfs_new_test_ctx() fails after param_ctx was already built=2E > >Patches 2-4 fix missing contexts->nr checks before dereferencing >contexts_arr[0]=2E A user can trigger these by setting nr_contexts to 0 >via sysfs and then issuing commands that assume a context exists: > > - Patch 2: CLEAR_SCHEMES_TRIED_REGIONS handler in damon_sysfs_handle_cm= d() > - Patch 3: damon_sysfs_update_schemes_tried_regions(), reached via > UPDATE_SCHEMES_TRIED_BYTES and UPDATE_SCHEMES_TRIED_REGIONS > - Patch 4: damon_sysfs_repeat_call_fn(), reachable when nr_contexts is > set to 0 while DAMON is running > >Josh Law (4): > mm/damon/sysfs: fix param_ctx leak on damon_sysfs_new_test_ctx() > failure > mm/damon/sysfs: check contexts->nr before clear_schemes_tried_regions > mm/damon/sysfs: check contexts->nr in update_schemes_tried_regions > mm/damon/sysfs: check contexts->nr in repeat_call_fn > > mm/damon/sysfs=2Ec | 11 ++++++++++- > 1 file changed, 10 insertions(+), 1 deletion(-) > [0] I don't think this is right=2E Probably best you don't listen to that=2E= =2E V/R Josh Law