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This fact is > ensured by the creation of field accessors to previously initialized > fields. >=20 > Since we missed this very important fact from the beginning [1], > document it in the code. >=20 > Link: https://rust-for-linux.zulipchat.com/#narrow/channel/561532-pin-ini= t/topic/initialized.20field.20accessor.20detection/with/576210658 [1] > Fixes: 90e53c5e70a6 ("rust: add pin-init API core") > Cc: stable@vger.kernel.org # 6.19.y and 6.18.y: patch should apply withou= t issues > Cc: stable@vger.kernel.org # 6.12.y and 6.6.y: need prerequisite see belo= w `---` for more info Hmm, if this patch is applied as is, the --- below is going to be cut out a= nd this line wouldn't make sense. Perhaps we should just put Cc: stable@vger.kernel.org # 6.12.y and 6.6.y: need commit 42415d163e5d= ("rust: pin-init: add references to previously initialized fields") Or leave this cc out and ask for manual picking? > Signed-off-by: Benno Lossin Reviewed-by: Gary Guo Best, Gary > --- > As already explained in the previous email, we discovered an unsoundness > in pin-init that exists since the beginning, but was unknowingly fixed > in commit 42415d163e5d ("rust: pin-init: add references to previously > initialized fields"). >=20 > We introduced pin-init in 90e53c5e70a6 ("rust: add pin-init API core"), > which was included in 6.4. The affected stable trees that are still > maintained are: 6.12 and 6.6. Note that 6.18 and 6.19 already contain > 42415d163e5d, so they are unaffected. >=20 > We still should backport this piece of documentation explaining the need > for the field accessors for soundness. For this reasons we also want to > backport it to 6.18 and 6.19. >=20 > Note that this patch depends on 42415d163e5d; so the only versions this > patch can go in directly are 6.18 and 6.19. I will send separate patch > series' for the older versions. The series' will include a backport of > 42415d163e5d as well as a modified version of this patch, since this > patch depends on the `syn` rewrite, which is not present in older > versions. > --- > rust/pin-init/internal/src/init.rs | 8 ++++++++ > 1 file changed, 8 insertions(+)