In the Linux kernel, the following vulnerability has been resolved:
zram: set default primary compressor in zram_destroy_comps()
Patch series "zram: fix zram issues reported by sashiko". Sashiko drove by and reported [1] a couple of zram issues:
a possible BUG_ON() in zlib code due to missing winbits range
validation and one possible NULL-ptr dereference in zcomp. Both are low risk yet still worth fixing.
This patch (of 2):
zram_destroy_comps() resets all compressors and leaves them set to NULL,
including the primary one, which is invalid device state, as now
comp_algorithm_show()->strcmp() can be called on a NULL compressor. Set
default primary compressor in zram_destroy_comps().
References 4
https://git.kernel.org/stable/c/5cec3e60e9f2d1324179df3aa91656f90095cf8f
416baaa9-dc9f-4396-8d5f-8c081fb06d67
https://git.kernel.org/stable/c/dde75313eed0b014c437f48dd75c0308b592cbf9
416baaa9-dc9f-4396-8d5f-8c081fb06d67
https://git.kernel.org/stable/c/dea8f13c3dfad8b990f8ea96c997aabeebbc1d22
416baaa9-dc9f-4396-8d5f-8c081fb06d67
https://git.kernel.org/stable/c/4bf3328eeec9afc2a55632ff47fc18101ea62d73
416baaa9-dc9f-4396-8d5f-8c081fb06d67