From: Pali Rohár pali@kernel.org
[ Upstream commit 6aa9f1c9cd09c1c39a35da4fe5f43446ec18ce1e ]
When converting access_flags to SMBOPEN mode, check for all possible access flags, not only GENERIC_READ and GENERIC_WRITE flags.
Signed-off-by: Pali Rohár pali@kernel.org Signed-off-by: Steve French stfrench@microsoft.com Signed-off-by: Sasha Levin sashal@kernel.org --- fs/smb/client/cifssmb.c | 32 ++++++++++++++++++++++++-------- 1 file changed, 24 insertions(+), 8 deletions(-)
diff --git a/fs/smb/client/cifssmb.c b/fs/smb/client/cifssmb.c index 4fc9485c5d91a..c2abe79f0dd3b 100644 --- a/fs/smb/client/cifssmb.c +++ b/fs/smb/client/cifssmb.c @@ -1038,15 +1038,31 @@ static __u16 convert_disposition(int disposition) static int access_flags_to_smbopen_mode(const int access_flags) { - int masked_flags = access_flags & (GENERIC_READ | GENERIC_WRITE); - - if (masked_flags == GENERIC_READ) - return SMBOPEN_READ; - else if (masked_flags == GENERIC_WRITE) + /* + * SYSTEM_SECURITY grants both read and write access to SACL, treat is as read/write. + * MAXIMUM_ALLOWED grants as many access as possible, so treat it as read/write too. + * SYNCHRONIZE as is does not grant any specific access, so do not check its mask. + * If only SYNCHRONIZE bit is specified then fallback to read access. + */ + bool with_write_flags = access_flags & (FILE_WRITE_DATA | FILE_APPEND_DATA | FILE_WRITE_EA | + FILE_DELETE_CHILD | FILE_WRITE_ATTRIBUTES | DELETE | + WRITE_DAC | WRITE_OWNER | SYSTEM_SECURITY | + MAXIMUM_ALLOWED | GENERIC_WRITE | GENERIC_ALL); + bool with_read_flags = access_flags & (FILE_READ_DATA | FILE_READ_EA | FILE_EXECUTE | + FILE_READ_ATTRIBUTES | READ_CONTROL | + SYSTEM_SECURITY | MAXIMUM_ALLOWED | GENERIC_ALL | + GENERIC_EXECUTE | GENERIC_READ); + bool with_execute_flags = access_flags & (FILE_EXECUTE | MAXIMUM_ALLOWED | GENERIC_ALL | + GENERIC_EXECUTE); + + if (with_write_flags && with_read_flags) + return SMBOPEN_READWRITE; + else if (with_write_flags) return SMBOPEN_WRITE; - - /* just go for read/write */ - return SMBOPEN_READWRITE; + else if (with_execute_flags) + return SMBOPEN_EXECUTE; + else + return SMBOPEN_READ; }
int