From cd0b16c1c3cda12dbed1f8de8f1a9b0591990724 Mon Sep 17 00:00:00 2001 From: Trond Myklebust Date: Sat, 13 Oct 2012 00:30:28 -0400 Subject: NLM: nlm_lookup_file() may return NLMv4-specific error codes If the filehandle is stale, or open access is denied for some reason, nlm_fopen() may return one of the NLMv4-specific error codes nlm4_stale_fh or nlm4_failed. These get passed right through nlm_lookup_file(), and so when nlmsvc_retrieve_args() calls the latter, it needs to filter the result through the cast_status() machinery. Failure to do so, will trigger the BUG_ON() in encode_nlm_stat... Signed-off-by: Trond Myklebust Reported-by: Larry McVoy Cc: stable@kernel.org Signed-off-by: J. Bruce Fields --- fs/lockd/clntxdr.c | 2 +- fs/lockd/svcproc.c | 3 ++- 2 files changed, 3 insertions(+), 2 deletions(-) diff --git a/fs/lockd/clntxdr.c b/fs/lockd/clntxdr.c index d269ada7670..982d2676e1f 100644 --- a/fs/lockd/clntxdr.c +++ b/fs/lockd/clntxdr.c @@ -223,7 +223,7 @@ static void encode_nlm_stat(struct xdr_stream *xdr, { __be32 *p; - BUG_ON(be32_to_cpu(stat) > NLM_LCK_DENIED_GRACE_PERIOD); + WARN_ON_ONCE(be32_to_cpu(stat) > NLM_LCK_DENIED_GRACE_PERIOD); p = xdr_reserve_space(xdr, 4); *p = stat; } diff --git a/fs/lockd/svcproc.c b/fs/lockd/svcproc.c index 3009a365e08..21171f0c647 100644 --- a/fs/lockd/svcproc.c +++ b/fs/lockd/svcproc.c @@ -68,7 +68,8 @@ nlmsvc_retrieve_args(struct svc_rqst *rqstp, struct nlm_args *argp, /* Obtain file pointer. Not used by FREE_ALL call. */ if (filp != NULL) { - if ((error = nlm_lookup_file(rqstp, &file, &lock->fh)) != 0) + error = cast_status(nlm_lookup_file(rqstp, &file, &lock->fh)); + if (error != 0) goto no_locks; *filp = file; -- cgit v1.2.3 From 212ba90696ab4884e2025b0b13726d67aadc2cd4 Mon Sep 17 00:00:00 2001 From: Sasha Levin Date: Tue, 17 Jul 2012 00:01:26 +0200 Subject: SUNRPC: Prevent kernel stack corruption on long values of flush The buffer size in read_flush() is too small for the longest possible values for it. This can lead to a kernel stack corruption: [ 43.047329] Kernel panic - not syncing: stack-protector: Kernel stack is corrupted in: ffffffff833e64b4 [ 43.047329] [ 43.049030] Pid: 6015, comm: trinity-child18 Tainted: G W 3.5.0-rc7-next-20120716-sasha #221 [ 43.050038] Call Trace: [ 43.050435] [] panic+0xcd/0x1f4 [ 43.050931] [] ? read_flush.isra.7+0xe4/0x100 [ 43.051602] [] __stack_chk_fail+0x16/0x20 [ 43.052206] [] read_flush.isra.7+0xe4/0x100 [ 43.052951] [] ? read_flush_pipefs+0x30/0x30 [ 43.053594] [] read_flush_procfs+0x2c/0x30 [ 43.053596] [] proc_reg_read+0x9c/0xd0 [ 43.053596] [] ? proc_reg_write+0xd0/0xd0 [ 43.053596] [] do_loop_readv_writev+0x4b/0x90 [ 43.053596] [] do_readv_writev+0xf6/0x1d0 [ 43.053596] [] vfs_readv+0x3e/0x60 [ 43.053596] [] sys_readv+0x48/0xb0 [ 43.053596] [] system_call_fastpath+0x1a/0x1f Signed-off-by: Sasha Levin Cc: stable@kernel.org Signed-off-by: J. Bruce Fields --- net/sunrpc/cache.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/net/sunrpc/cache.c b/net/sunrpc/cache.c index 2a68bb3db77..fc2f7aa4dca 100644 --- a/net/sunrpc/cache.c +++ b/net/sunrpc/cache.c @@ -1409,11 +1409,11 @@ static ssize_t read_flush(struct file *file, char __user *buf, size_t count, loff_t *ppos, struct cache_detail *cd) { - char tbuf[20]; + char tbuf[22]; unsigned long p = *ppos; size_t len; - sprintf(tbuf, "%lu\n", convert_to_wallclock(cd->flush_time)); + snprintf(tbuf, sizeof(tbuf), "%lu\n", convert_to_wallclock(cd->flush_time)); len = strlen(tbuf); if (p >= len) return 0; -- cgit v1.2.3