| Message ID | 20200623003236.830149-5-tyhicks@linux.microsoft.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | ima: Fix rule parsing bugs and extend KEXEC_CMDLINE rule support | expand |
diff --git a/security/integrity/ima/ima_policy.c b/security/integrity/ima/ima_policy.c index 94ca3b8abb69..ee5152ecd3d9 100644 --- a/security/integrity/ima/ima_policy.c +++ b/security/integrity/ima/ima_policy.c @@ -919,6 +919,7 @@ static int ima_lsm_rule_init(struct ima_rule_entry *entry, if (ima_rules == &ima_default_rules) { kfree(entry->lsm[lsm_rule].args_p); + entry->lsm[lsm_rule].args_p = NULL; result = -EINVAL; } else result = 0; @@ -1410,7 +1411,7 @@ ssize_t ima_parse_add_rule(char *rule) result = ima_parse_rule(p, entry); if (result) { - kfree(entry); + ima_free_rule(entry); integrity_audit_msg(AUDIT_INTEGRITY_STATUS, NULL, NULL, op, "invalid-policy", result, audit_info);
Use ima_free_rule() to fix memory leaks of allocated ima_rule_entry members, such as .fsname and .keyrings, when an error is encountered during rule parsing. Set the args_p pointer to NULL after freeing it in the error path of ima_lsm_rule_init() so that it isn't freed twice. This fixes a memory leak seen when loading an rule that contains an additional piece of allocated memory, such as an fsname, followed by an invalid conditional: # echo "measure fsname=tmpfs bad=cond" > /sys/kernel/security/ima/policy -bash: echo: write error: Invalid argument # echo scan > /sys/kernel/debug/kmemleak # cat /sys/kernel/debug/kmemleak unreferenced object 0xffff98e7e4ece6c0 (size 8): comm "bash", pid 672, jiffies 4294791843 (age 21.855s) hex dump (first 8 bytes): 74 6d 70 66 73 00 6b a5 tmpfs.k. backtrace: [<00000000abab7413>] kstrdup+0x2e/0x60 [<00000000f11ede32>] ima_parse_add_rule+0x7d4/0x1020 [<00000000f883dd7a>] ima_write_policy+0xab/0x1d0 [<00000000b17cf753>] vfs_write+0xde/0x1d0 [<00000000b8ddfdea>] ksys_write+0x68/0xe0 [<00000000b8e21e87>] do_syscall_64+0x56/0xa0 [<0000000089ea7b98>] entry_SYSCALL_64_after_hwframe+0x44/0xa9 Fixes: f1b08bbcbdaf ("ima: define a new policy condition based on the filesystem name") Fixes: 2b60c0ecedf8 ("IMA: Read keyrings= option from the IMA policy") Signed-off-by: Tyler Hicks <tyhicks@linux.microsoft.com> --- security/integrity/ima/ima_policy.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)