Description: mm/writeback: fix possible divide-by-zero in wb_dirty_limits(), again
References:
Notes:
 carnil> Introduced in f6789593d5ce ("mm/page-writeback.c: fix divide by zero in
 carnil> bdi_dirty_limits()"). Vulnerable versions: 3.12.27 3.14.16 3.15.9 3.16.
Bugs:
upstream: released (6.8-rc3) [9319b647902cbd5cc884ac08a8a6d54ce111fc78]
6.7-upstream-stable: released (6.7.6) [65977bed167a92e87085e757fffa5798f7314c9f]
6.6-upstream-stable: released (6.6.18) [ec18ec230301583395576915d274b407743d8f6c]
6.1-upstream-stable: released (6.1.79) [16b1025eaa8fc223ab4273ece20d1c3a4211a95d]
5.10-upstream-stable: released (5.10.210) [81e7d2530d458548b90a5c5e76b77ad5e5d1c0df]
4.19-upstream-stable: released (4.19.307) [c593d26fb5d577ef31b6e49a31e08ae3ebc1bc1e]
sid: released (6.7.7-1)
6.1-bookworm-security: released (6.1.82-1)
5.10-bullseye-security: needed
4.19-buster-security: needed