On 09/16/2016 10:30 AM, Stephen Smalley wrote:
> On 09/15/2016 07:13 PM, william.c.robe...@intel.com wrote:
>> From: William Roberts <william.c.robe...@intel.com>
>>
>> patch 5e15a52aaa cleans up the process_file() but introduced
>> a bug. If the binary file cannot be opened, always attempt
>> to fall back to the textual file, this was not occurring.
>>
>> The logic should be:
>> 1. Open the newest file based on base path + suffix vs
>> base_path + suffix + ".bin".
>> 2. If anything fails, attempt base_path + suffix.
>>
>> In the case that the file_contexts was the newest file and
>> used for processing fails, it will attempt the same failure
>> recovery, which will fail. It was decided to keep it this
>> was for simplicity.
>
> I don't like the approach. What we want is:
> - if .bin file exists and is not older, try to load it,
> - if any of the above fails (i.e. .bin file does not exist, is older, or
> cannot be loaded for any reason), then load the text file.
>
> We shouldn't try loading the text file twice.
>
> Also, attached is checkpatch output for your patch. Please fix.
Also, there is a further wrinkle: Android passes in file_contexts.bin as
the SELABEL_OPT_PATH, so that is the base path. Under the old logic
(before your original clean up patch), we would open that file, detect
that it is binary, and then load it. Under the current logic, we'll
open file_contexts.bin, then try to open file_contexts.bin.bin (which
will fail), and then use the first one.
Wondering if we just need to revert.
>
>>
>> Signed-off-by: William Roberts <william.c.robe...@intel.com>
>> ---
>> libselinux/src/label_file.c | 41 +++++++++++++++++++++++++++--------------
>> 1 file changed, 27 insertions(+), 14 deletions(-)
>>
>> diff --git a/libselinux/src/label_file.c b/libselinux/src/label_file.c
>> index 9faecdb..0dee059 100644
>> --- a/libselinux/src/label_file.c
>> +++ b/libselinux/src/label_file.c
>> @@ -447,7 +447,7 @@ static bool fcontext_is_binary(FILE *fp)
>> #define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0]))
>>
>> static FILE *open_file(const char *path, const char *suffix,
>> - char *save_path, size_t len, struct stat *sb)
>> + char *save_path, size_t len, struct stat *sb, bool
>> force_text)
>> {
>> unsigned int i;
>> int rc;
>> @@ -469,7 +469,11 @@ static FILE *open_file(const char *path, const char
>> *suffix,
>> return NULL;
>> }
>>
>> - for (i = 0; i < ARRAY_SIZE(fdetails); i++) {
>> + size_t array_size = ARRAY_SIZE(fdetails);
>> + if (force_text)
>> + array_size--;
>> +
>> + for (i = 0; i < array_size; i++) {
>>
>> /* This handles the case if suffix is null */
>> path = rolling_append(stack_path, fdetails[i].suffix,
>> @@ -515,24 +519,33 @@ static int process_file(const char *path, const char
>> *suffix,
>> const char *prefix, struct selabel_digest *digest)
>> {
>> int rc;
>> + unsigned int i;
>> struct stat sb;
>> FILE *fp = NULL;
>> char found_path[PATH_MAX];
>>
>> - fp = open_file(path, suffix, found_path, sizeof(found_path), &sb);
>> - if (fp == NULL)
>> - return -1;
>> + /*
>> + * first path open the newest modified file, if it fails, the second
>> + * pass falls through to the plain text file.
>> + */
>> + for(i=0; i < 2; i++) {
>> + fp = open_file(path, suffix, found_path, sizeof(found_path),
>> &sb,
>> + i > 0);
>> + if (fp == NULL)
>> + return -1;
>>
>> - rc = fcontext_is_binary(fp) ?
>> - load_mmap(fp, sb.st_size, rec, found_path) :
>> - process_text_file(fp, prefix, rec, found_path);
>> - if (rc < 0)
>> - goto out;
>> + rc = fcontext_is_binary(fp) ?
>> + load_mmap(fp, sb.st_size, rec, found_path) :
>> + process_text_file(fp, prefix, rec, found_path);
>> + if (!rc)
>> + rc = digest_add_specfile(digest, fp, NULL, sb.st_size,
>> found_path);
>>
>> - rc = digest_add_specfile(digest, fp, NULL, sb.st_size, found_path);
>> -out:
>> - fclose(fp);
>> - return rc;
>> + fclose(fp);
>> +
>> + if(!rc)
>> + return 0;
>> + }
>> + return -1;
>> }
>>
>> static void closef(struct selabel_handle *rec);
>>
>
>
>
> _______________________________________________
> Selinux mailing list
> Selinux@tycho.nsa.gov
> To unsubscribe, send email to selinux-le...@tycho.nsa.gov.
> To get help, send an email containing "help" to selinux-requ...@tycho.nsa.gov.
>
_______________________________________________
Selinux mailing list
Selinux@tycho.nsa.gov
To unsubscribe, send email to selinux-le...@tycho.nsa.gov.
To get help, send an email containing "help" to selinux-requ...@tycho.nsa.gov.
