From: Andy Grover Date: Fri, 30 Oct 2009 08:51:54 +0000 (+0000) Subject: RDS: Fix potential race around rds_i[bw]_allocation X-Git-Tag: v2.6.33-rc1~388^2~573 X-Git-Url: http://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=86357b19bcabd9355937f3fb84f90ba9fe76a5d3;p=pandora-kernel.git RDS: Fix potential race around rds_i[bw]_allocation "At rds_ib_recv_refill_one(), it first executes atomic_read(&rds_ib_allocation) for if-condition checking, and then executes atomic_inc(&rds_ib_allocation) if the condition was not satisfied. However, if any other code which updates rds_ib_allocation executes between these two atomic operation executions, it seems that it may result race condition. (especially when rds_ib_allocation + 1 == rds_ib_sysctl_max_recv_allocation)" This patch fixes this by using atomic_inc_unless to eliminate the possibility of allocating more than rds_ib_sysctl_max_recv_allocation and then decrementing the count if the allocation fails. It also makes an identical change to the iwarp transport. Reported-by: Shin Hong Signed-off-by: Andy Grover Signed-off-by: David S. Miller --- Reading git-diff-tree failed