diff options
| author | Eric Biggers <ebiggers@google.com> | 2019-08-22 07:54:41 +0200 |
|---|---|---|
| committer | Casey Schaufler <casey@schaufler-ca.com> | 2019-09-04 18:37:07 +0200 |
| commit | e5bfad3d7acc5702f32aafeb388362994f4d7bd0 (patch) | |
| tree | c9daa0267c2dd110e5a8ccbed94ac8c8edb9c6e6 | |
| parent | security: smack: Fix possible null-pointer dereferences in smack_socket_sock_... (diff) | |
| download | linux-e5bfad3d7acc5702f32aafeb388362994f4d7bd0.tar.xz linux-e5bfad3d7acc5702f32aafeb388362994f4d7bd0.zip | |
smack: use GFP_NOFS while holding inode_smack::smk_lock
inode_smack::smk_lock is taken during smack_d_instantiate(), which is
called during a filesystem transaction when creating a file on ext4.
Therefore to avoid a deadlock, all code that takes this lock must use
GFP_NOFS, to prevent memory reclaim from waiting for the filesystem
transaction to complete.
Reported-by: syzbot+0eefc1e06a77d327a056@syzkaller.appspotmail.com
Cc: stable@vger.kernel.org
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
| -rw-r--r-- | security/smack/smack_access.c | 6 | ||||
| -rw-r--r-- | security/smack/smack_lsm.c | 2 |
2 files changed, 4 insertions, 4 deletions
diff --git a/security/smack/smack_access.c b/security/smack/smack_access.c index f1c93a7be9ec..38ac3da4e791 100644 --- a/security/smack/smack_access.c +++ b/security/smack/smack_access.c @@ -465,7 +465,7 @@ char *smk_parse_smack(const char *string, int len) if (i == 0 || i >= SMK_LONGLABEL) return ERR_PTR(-EINVAL); - smack = kzalloc(i + 1, GFP_KERNEL); + smack = kzalloc(i + 1, GFP_NOFS); if (smack == NULL) return ERR_PTR(-ENOMEM); @@ -500,7 +500,7 @@ int smk_netlbl_mls(int level, char *catset, struct netlbl_lsm_secattr *sap, if ((m & *cp) == 0) continue; rc = netlbl_catmap_setbit(&sap->attr.mls.cat, - cat, GFP_KERNEL); + cat, GFP_NOFS); if (rc < 0) { netlbl_catmap_free(sap->attr.mls.cat); return rc; @@ -536,7 +536,7 @@ struct smack_known *smk_import_entry(const char *string, int len) if (skp != NULL) goto freeout; - skp = kzalloc(sizeof(*skp), GFP_KERNEL); + skp = kzalloc(sizeof(*skp), GFP_NOFS); if (skp == NULL) { skp = ERR_PTR(-ENOMEM); goto freeout; diff --git a/security/smack/smack_lsm.c b/security/smack/smack_lsm.c index 516f7ba96f1e..abeb09c30633 100644 --- a/security/smack/smack_lsm.c +++ b/security/smack/smack_lsm.c @@ -288,7 +288,7 @@ static struct smack_known *smk_fetch(const char *name, struct inode *ip, if (!(ip->i_opflags & IOP_XATTR)) return ERR_PTR(-EOPNOTSUPP); - buffer = kzalloc(SMK_LONGLABEL, GFP_KERNEL); + buffer = kzalloc(SMK_LONGLABEL, GFP_NOFS); if (buffer == NULL) return ERR_PTR(-ENOMEM); |