diff options
| author | Fabio M. De Francesco <fmdefrancesco@gmail.com> | 2022-02-23 11:02:52 +0100 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2022-03-02 11:47:59 +0100 |
| commit | 062772d5cc8cd4018585cdbc2c03457dfb5a3d88 (patch) | |
| tree | 1ade99fabd48bdfc4fe51b0cba6d086af00b518f /net/smc/smc_pnet.h | |
| parent | e96e204ee6fa46702f6c94c3c69a09e69e0eac52 (diff) | |
net/smc: Use a mutex for locking "struct smc_pnettable"
commit 7ff57e98fb78ad94edafbdc7435f2d745e9e6bb5 upstream.
smc_pnetid_by_table_ib() uses read_lock() and then it calls smc_pnet_apply_ib()
which, in turn, calls mutex_lock(&smc_ib_devices.mutex).
read_lock() disables preemption. Therefore, the code acquires a mutex while in
atomic context and it leads to a SAC bug.
Fix this bug by replacing the rwlock with a mutex.
Reported-and-tested-by: syzbot+4f322a6d84e991c38775@syzkaller.appspotmail.com
Fixes: 64e28b52c7a6 ("net/smc: add pnet table namespace support")
Confirmed-by: Tony Lu <tonylu@linux.alibaba.com>
Signed-off-by: Fabio M. De Francesco <fmdefrancesco@gmail.com>
Acked-by: Karsten Graul <kgraul@linux.ibm.com>
Link: https://lore.kernel.org/r/20220223100252.22562-1-fmdefrancesco@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'net/smc/smc_pnet.h')
| -rw-r--r-- | net/smc/smc_pnet.h | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/net/smc/smc_pnet.h b/net/smc/smc_pnet.h index 14039272f7e4..80a88eea4949 100644 --- a/net/smc/smc_pnet.h +++ b/net/smc/smc_pnet.h @@ -29,7 +29,7 @@ struct smc_link_group; * @pnetlist: List of PNETIDs */ struct smc_pnettable { - rwlock_t lock; + struct mutex lock; struct list_head pnetlist; }; |