path: root/ipc/compat.c
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authorAlexei Starovoitov <>2015-05-28 19:26:02 -0700
committerDavid S. Miller <>2015-05-31 00:27:51 -0700
commitabf2e7d6e2e315b32ee00067a69aaad2cf4e1b3f (patch)
tree073ee9134421f2ab9edcd226a48de1a4bea72554 /ipc/compat.c
parentd1f5f2bb91094c9e6f7c98610d637ffdaedef116 (diff)
bpf: add missing rcu protection when releasing programs from prog_array
Normally the program attachment place (like sockets, qdiscs) takes care of rcu protection and calls bpf_prog_put() after a grace period. The programs stored inside prog_array may not be attached anywhere, so prog_array needs to take care of preserving rcu protection. Otherwise bpf_tail_call() will race with bpf_prog_put(). To solve that introduce bpf_prog_put_rcu() helper function and use it in 3 places where unattached program can decrement refcnt: closing program fd, deleting/replacing program in prog_array. Fixes: 04fd61ab36ec ("bpf: allow bpf programs to tail-call other bpf programs") Reported-by: Martin Schwidefsky <> Signed-off-by: Alexei Starovoitov <> Acked-by: Daniel Borkmann <> Signed-off-by: David S. Miller <>
Diffstat (limited to 'ipc/compat.c')
0 files changed, 0 insertions, 0 deletions