summaryrefslogtreecommitdiff
path: root/mm
diff options
context:
space:
mode:
authorLinus Torvalds <torvalds@linux-foundation.org>2021-06-15 09:26:19 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2021-06-15 10:47:51 -0700
commit94f0b2d4a1d0c52035aef425da5e022bd2cb1c71 (patch)
treea646956edefb55000e34cf429e75add7b32f0367 /mm
parenta33d62662d275cee22888fa7760fe09d5b9cd1f9 (diff)
proc: only require mm_struct for writing
Commit 591a22c14d3f ("proc: Track /proc/$pid/attr/ opener mm_struct") we started using __mem_open() to track the mm_struct at open-time, so that we could then check it for writes. But that also ended up making the permission checks at open time much stricter - and not just for writes, but for reads too. And that in turn caused a regression for at least Fedora 29, where NIC interfaces fail to start when using NetworkManager. Since only the write side wanted the mm_struct test, ignore any failures by __mem_open() at open time, leaving reads unaffected. The write() time verification of the mm_struct pointer will then catch the failure case because a NULL pointer will not match a valid 'current->mm'. Link: https://lore.kernel.org/netdev/YMjTlp2FSJYvoyFa@unreal/ Fixes: 591a22c14d3f ("proc: Track /proc/$pid/attr/ opener mm_struct") Reported-and-tested-by: Leon Romanovsky <leon@kernel.org> Cc: Kees Cook <keescook@chromium.org> Cc: Christian Brauner <christian.brauner@ubuntu.com> Cc: Andrea Righi <andrea.righi@canonical.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'mm')
0 files changed, 0 insertions, 0 deletions