Windows: Prevent fs fetchdata offset bug error from propagating to caller

When the file server fetchdata offset bug is triggered and detected,
not only do we have to behave as if 'length_found' is zero, but we
also must ignore the RXGEN_CC_UNMARSHAL error that will be returned
from rx_EndCall() due to the parsing error that occurred during the
rx_Read32() call.

LICENSE MIT

Reviewed-on: http://gerrit.openafs.org/634
Tested-by: Jeffrey Altman <jaltman@openafs.org>
Reviewed-by: Derrick Brashear <shadow@dementia.org>
Reviewed-by: Jeffrey Altman <jaltman@openafs.org>

diff --git a/src/WINNT/afsd/cm_dcache.c b/src/WINNT/afsd/cm_dcache.c
index c3b53d9..94010d9 100644 (file)
--- a/src/WINNT/afsd/cm_dcache.c
+++ b/src/WINNT/afsd/cm_dcache.c
@@ -1850,8 +1850,11 @@ long cm_GetBuffer(cm_scache_t *scp, cm_buf_t *bufp, int *cpffp, cm_user_t *userp
         if (code1 == RXKADUNKNOWNKEY)
             osi_Log0(afsd_logp, "CALL EndCall returns RXKADUNKNOWNKEY");
 
+        /* If we are avoiding a file server bug, ignore the error state */
+        if (fs_fetchdata_offset_bug && first_read && length_found == 0 && code == -451)
+            code = 0;
         /* Prefer the error value from FetchData over rx_EndCall */
-        if (code == 0 && code1 != 0)
+        else if (code == 0 && code1 != 0)
             code = code1;
         osi_Log0(afsd_logp, "CALL FetchData DONE");