From: Arnd Bergmann arnd@arndb.de

[ Upstream commit aff12700b8dd7422bfe2277696e192af4df9de8f ]

idt_scan_mws() puts a large fixed-size array on the stack and copies it into a smaller dynamically allocated array at the end. On 32-bit targets, the fixed size can easily exceed the warning limit for possible stack overflow:

drivers/ntb/hw/idt/ntb_hw_idt.c:1041:27: error: stack frame size (1032) exceeds limit (1024) in 'idt_scan_mws' [-Werror,-Wframe-larger-than]

Change it to instead just always use dynamic allocation for the array from the start. It's too big for the stack, but not actually all that much for a permanent allocation.

Reported-by: kernel test robot lkp@intel.com Closes: https://lore.kernel.org/all/202205111109.PiKTruEj-lkp@intel.com/ Signed-off-by: Arnd Bergmann arnd@arndb.de Reviewed-by: Dave Jiang dave.jiang@intel.com Reviewed-by: Damien Le Moal dlemoal@kernel.org Signed-off-by: Jon Mason jdmason@kudzu.us Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/ntb/hw/idt/ntb_hw_idt.c | 18 +++++++----------- 1 file changed, 7 insertions(+), 11 deletions(-)

diff --git a/drivers/ntb/hw/idt/ntb_hw_idt.c b/drivers/ntb/hw/idt/ntb_hw_idt.c index 48823b53ede3e..22aaa60d2d384 100644 --- a/drivers/ntb/hw/idt/ntb_hw_idt.c +++ b/drivers/ntb/hw/idt/ntb_hw_idt.c @@ -1041,7 +1041,7 @@ static inline char *idt_get_mw_name(enum idt_mw_type mw_type) static struct idt_mw_cfg *idt_scan_mws(struct idt_ntb_dev *ndev, int port, unsigned char *mw_cnt) { - struct idt_mw_cfg mws[IDT_MAX_NR_MWS], *ret_mws; + struct idt_mw_cfg *mws; const struct idt_ntb_bar *bars; enum idt_mw_type mw_type; unsigned char widx, bidx, en_cnt; @@ -1049,6 +1049,11 @@ static struct idt_mw_cfg *idt_scan_mws(struct idt_ntb_dev *ndev, int port, int aprt_size; u32 data;

+ mws = devm_kcalloc(&ndev->ntb.pdev->dev, IDT_MAX_NR_MWS, + sizeof(*mws), GFP_KERNEL); + if (!mws) + return ERR_PTR(-ENOMEM); + /* Retrieve the array of the BARs registers */ bars = portdata_tbl[port].bars;

@@ -1103,16 +1108,7 @@ static struct idt_mw_cfg *idt_scan_mws(struct idt_ntb_dev *ndev, int port, } }

- /* Allocate memory for memory window descriptors */ - ret_mws = devm_kcalloc(&ndev->ntb.pdev->dev, *mw_cnt, sizeof(*ret_mws), - GFP_KERNEL); - if (!ret_mws) - return ERR_PTR(-ENOMEM); - - /* Copy the info of detected memory windows */ - memcpy(ret_mws, mws, (*mw_cnt)*sizeof(*ret_mws)); - - return ret_mws; + return mws; }

/*

From: Dominique Martinet asmadeus@codewreck.org

[ Upstream commit d0259a856afca31d699b706ed5e2adf11086c73b ]

In p9_client_write() and p9_client_read_once(), if the server incorrectly replies with success but a negative write/read count then we would consider written (negative) <= rsize (positive) because both variables were signed.

Make variables unsigned to avoid this problem.

The reproducer linked below now fails with the following error instead of a null pointer deref: 9pnet: bogus RWRITE count (4294967295 > 3)

Reported-by: Robert Morris rtm@mit.edu Closes: https://lore.kernel.org/16271.1734448631@26-5-164.dynamic.csail.mit.edu Message-ID: 20250319-9p_unsigned_rw-v3-1-71327f1503d0@codewreck.org Reviewed-by: Christian Schoenebeck linux_oss@crudebyte.com Signed-off-by: Dominique Martinet asmadeus@codewreck.org Signed-off-by: Sasha Levin sashal@kernel.org --- net/9p/client.c | 30 ++++++++++++++++-------------- 1 file changed, 16 insertions(+), 14 deletions(-)

diff --git a/net/9p/client.c b/net/9p/client.c index d841d82e908fe..cf73fe306219a 100644 --- a/net/9p/client.c +++ b/net/9p/client.c @@ -1547,7 +1547,8 @@ p9_client_read_once(struct p9_fid *fid, u64 offset, struct iov_iter *to, struct p9_client *clnt = fid->clnt; struct p9_req_t *req; int count = iov_iter_count(to); - int rsize, received, non_zc = 0; + u32 rsize, received; + bool non_zc = false; char *dataptr;

*err = 0; @@ -1570,7 +1571,7 @@ p9_client_read_once(struct p9_fid *fid, u64 offset, struct iov_iter *to, 0, 11, "dqd", fid->fid, offset, rsize); } else { - non_zc = 1; + non_zc = true; req = p9_client_rpc(clnt, P9_TREAD, "dqd", fid->fid, offset, rsize); } @@ -1591,11 +1592,11 @@ p9_client_read_once(struct p9_fid *fid, u64 offset, struct iov_iter *to, return 0; } if (rsize < received) { - pr_err("bogus RREAD count (%d > %d)\n", received, rsize); + pr_err("bogus RREAD count (%u > %u)\n", received, rsize); received = rsize; }

- p9_debug(P9_DEBUG_9P, "<<< RREAD count %d\n", received); + p9_debug(P9_DEBUG_9P, "<<< RREAD count %u\n", received);

if (non_zc) { int n = copy_to_iter(dataptr, received, to); @@ -1622,9 +1623,9 @@ p9_client_write(struct p9_fid *fid, u64 offset, struct iov_iter *from, int *err) *err = 0;

while (iov_iter_count(from)) { - int count = iov_iter_count(from); - int rsize = fid->iounit; - int written; + size_t count = iov_iter_count(from); + u32 rsize = fid->iounit; + u32 written;

if (!rsize || rsize > clnt->msize - P9_IOHDRSZ) rsize = clnt->msize - P9_IOHDRSZ; @@ -1632,7 +1633,7 @@ p9_client_write(struct p9_fid *fid, u64 offset, struct iov_iter *from, int *err) if (count < rsize) rsize = count;

- p9_debug(P9_DEBUG_9P, ">>> TWRITE fid %d offset %llu count %d (/%d)\n", + p9_debug(P9_DEBUG_9P, ">>> TWRITE fid %d offset %llu count %u (/%zu)\n", fid->fid, offset, rsize, count);

/* Don't bother zerocopy for small IO (< 1024) */ @@ -1658,11 +1659,11 @@ p9_client_write(struct p9_fid *fid, u64 offset, struct iov_iter *from, int *err) break; } if (rsize < written) { - pr_err("bogus RWRITE count (%d > %d)\n", written, rsize); + pr_err("bogus RWRITE count (%u > %u)\n", written, rsize); written = rsize; }

- p9_debug(P9_DEBUG_9P, "<<< RWRITE count %d\n", written); + p9_debug(P9_DEBUG_9P, "<<< RWRITE count %u\n", written);

p9_req_put(clnt, req); iov_iter_revert(from, count - written - iov_iter_count(from)); @@ -2049,7 +2050,8 @@ EXPORT_SYMBOL_GPL(p9_client_xattrcreate);

int p9_client_readdir(struct p9_fid *fid, char *data, u32 count, u64 offset) { - int err, rsize, non_zc = 0; + int err, non_zc = 0; + u32 rsize; struct p9_client *clnt; struct p9_req_t *req; char *dataptr; @@ -2058,7 +2060,7 @@ int p9_client_readdir(struct p9_fid *fid, char *data, u32 count, u64 offset)

iov_iter_kvec(&to, ITER_DEST, &kv, 1, count);

- p9_debug(P9_DEBUG_9P, ">>> TREADDIR fid %d offset %llu count %d\n", + p9_debug(P9_DEBUG_9P, ">>> TREADDIR fid %d offset %llu count %u\n", fid->fid, offset, count);

clnt = fid->clnt; @@ -2093,11 +2095,11 @@ int p9_client_readdir(struct p9_fid *fid, char *data, u32 count, u64 offset) goto free_and_error; } if (rsize < count) { - pr_err("bogus RREADDIR count (%d > %d)\n", count, rsize); + pr_err("bogus RREADDIR count (%u > %u)\n", count, rsize); count = rsize; }

- p9_debug(P9_DEBUG_9P, "<<< RREADDIR count %d\n", count); + p9_debug(P9_DEBUG_9P, "<<< RREADDIR count %u\n", count);

if (non_zc) memmove(data, dataptr, count);

From: Pavel Begunkov asml.silence@gmail.com

[ Upstream commit 390513642ee6763c7ada07f0a1470474986e6c1c ]

io_uring always switches requests to atomic refcounting for iowq execution before there is any parallilism by setting REQ_F_REFCOUNT, and the flag is not cleared until the request completes. That should be fine as long as the compiler doesn't make up a non existing value for the flags, however KCSAN still complains when the request owner changes oter flag bits:

BUG: KCSAN: data-race in io_req_task_cancel / io_wq_free_work ... read to 0xffff888117207448 of 8 bytes by task 3871 on cpu 0: req_ref_put_and_test io_uring/refs.h:22 [inline]

Skip REQ_F_REFCOUNT checks for iowq, we know it's set.

Reported-by: syzbot+903a2ad71fb3f1e47cf5@syzkaller.appspotmail.com Signed-off-by: Pavel Begunkov asml.silence@gmail.com Link: https://lore.kernel.org/r/d880bc27fb8c3209b54641be4ff6ac02b0e5789a.174367973... Signed-off-by: Jens Axboe axboe@kernel.dk Signed-off-by: Sasha Levin sashal@kernel.org --- io_uring/io_uring.c | 2 +- io_uring/refs.h | 7 +++++++ 2 files changed, 8 insertions(+), 1 deletion(-)

diff --git a/io_uring/io_uring.c b/io_uring/io_uring.c index efa7849b82c18..031b9c00c4489 100644 --- a/io_uring/io_uring.c +++ b/io_uring/io_uring.c @@ -1916,7 +1916,7 @@ struct io_wq_work *io_wq_free_work(struct io_wq_work *work) struct io_kiocb *req = container_of(work, struct io_kiocb, work); struct io_kiocb *nxt = NULL;

- if (req_ref_put_and_test(req)) { + if (req_ref_put_and_test_atomic(req)) { if (req->flags & IO_REQ_LINK_FLAGS) nxt = io_req_find_next(req); io_free_req(req); diff --git a/io_uring/refs.h b/io_uring/refs.h index 1336de3f2a30a..21a379b0f22d6 100644 --- a/io_uring/refs.h +++ b/io_uring/refs.h @@ -17,6 +17,13 @@ static inline bool req_ref_inc_not_zero(struct io_kiocb *req) return atomic_inc_not_zero(&req->refs); }

+static inline bool req_ref_put_and_test_atomic(struct io_kiocb *req) +{ + WARN_ON_ONCE(!(data_race(req->flags) & REQ_F_REFCOUNT)); + WARN_ON_ONCE(req_ref_zero_or_close_to_overflow(req)); + return atomic_dec_and_test(&req->refs); +} + static inline bool req_ref_put_and_test(struct io_kiocb *req) { if (likely(!(req->flags & REQ_F_REFCOUNT)))