diff mbox series

[net-next] genetlink: hold read cb_lock during iteration of genl_fam_idr in genl_bind()

Message ID 20220825081940.1283335-1-jiri@resnulli.us (mailing list archive)
State Accepted
Commit 8f1948bdcf2fb50e9092c0950c3c9ac591382101
Delegated to: Netdev Maintainers
Headers show
Series [net-next] genetlink: hold read cb_lock during iteration of genl_fam_idr in genl_bind() | expand

Checks

Context Check Description
netdev/tree_selection success Clearly marked for net-next
netdev/fixes_present success Fixes tag not required for -next series
netdev/subject_prefix success Link
netdev/cover_letter success Single patches do not need cover letters
netdev/patch_count success Link
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 342 this patch: 342
netdev/cc_maintainers success CCed 6 of 6 maintainers
netdev/build_clang success Errors and warnings before: 5 this patch: 5
netdev/module_param success Was 0 now: 0
netdev/verify_signedoff success Signed-off-by tag matches author and committer
netdev/check_selftest success No net selftest shell script
netdev/verify_fixes success No Fixes tag
netdev/build_allmodconfig_warn success Errors and warnings before: 342 this patch: 342
netdev/checkpatch success total: 0 errors, 0 warnings, 0 checks, 16 lines checked
netdev/kdoc success Errors and warnings before: 0 this patch: 0
netdev/source_inline success Was 0 now: 0

Commit Message

Jiri Pirko Aug. 25, 2022, 8:19 a.m. UTC 
From: Jiri Pirko <jiri@nvidia.com>

In genl_bind(), currently genl_lock and write cb_lock are taken
for iteration of genl_fam_idr and processing of static values
stored in struct genl_family. Take just read cb_lock for this task
as it is sufficient to guard the idr and the struct against
concurrent genl_register/unregister_family() calls.

This will allow to run genl command processing in genl_rcv() and
mnl_socket_setsockopt(.., NETLINK_ADD_MEMBERSHIP, ..) in parallel.

Reported-by: Vikas Gupta <vikas.gupta@broadcom.com>
Signed-off-by: Jiri Pirko <jiri@nvidia.com>
---
 net/netlink/genetlink.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

Comments

patchwork-bot+netdevbpf@kernel.org Aug. 27, 2022, 2 a.m. UTC | #1 
Hello:

This patch was applied to netdev/net-next.git (master)
by Jakub Kicinski <kuba@kernel.org>:

On Thu, 25 Aug 2022 10:19:40 +0200 you wrote:
> From: Jiri Pirko <jiri@nvidia.com>
> 
> In genl_bind(), currently genl_lock and write cb_lock are taken
> for iteration of genl_fam_idr and processing of static values
> stored in struct genl_family. Take just read cb_lock for this task
> as it is sufficient to guard the idr and the struct against
> concurrent genl_register/unregister_family() calls.
> 
> [...]

Here is the summary with links:
  - [net-next] genetlink: hold read cb_lock during iteration of genl_fam_idr in genl_bind()
    https://git.kernel.org/netdev/net-next/c/8f1948bdcf2f

You are awesome, thank you!
diff mbox series

Patch

diff --git a/net/netlink/genetlink.c b/net/netlink/genetlink.c
index 57010927e20a..76aed0571e3a 100644
--- a/net/netlink/genetlink.c
+++ b/net/netlink/genetlink.c
@@ -1362,7 +1362,7 @@  static int genl_bind(struct net *net, int group)
 	unsigned int id;
 	int ret = 0;
 
-	genl_lock_all();
+	down_read(&cb_lock);
 
 	idr_for_each_entry(&genl_fam_idr, family, id) {
 		const struct genl_multicast_group *grp;
@@ -1383,7 +1383,7 @@  static int genl_bind(struct net *net, int group)
 		break;
 	}
 
-	genl_unlock_all();
+	up_read(&cb_lock);
 	return ret;
 }