kernel/linux.git/drivers/s390/char, branch v6.1.168

s390/sclp: Fix SCCB present check

2025-08-28T14:26:13+00:00

commit 430fa71027b6ac9bb0ce5532b8d0676777d4219a upstream. Tracing code called by the SCLP interrupt handler contains early exits if the SCCB address associated with an interrupt is NULL. This check is performed after physical to virtual address translation. If the kernel identity mapping does not start at address zero, the resulting virtual address is never zero, so that the NULL checks won't work. Subsequently this may result in incorrect accesses to the first page of the identity mapping. Fix this by introducing a function that handles the NULL case before address translation. Fixes: ada1da31ce34 ("s390/sclp: sort out physical vs virtual pointers usage") Cc: stable@vger.kernel.org Reviewed-by: Alexander Gordeev Signed-off-by: Peter Oberparleiter Signed-off-by: Alexander Gordeev Signed-off-by: Greg Kroah-Hartman

s390/tty: Fix a potential memory leak bug

2025-05-02T05:47:02+00:00

[ Upstream commit ad9bb8f049717d64c5e62b2a44954be9f681c65b ] The check for get_zeroed_page() leads to a direct return and overlooked the memory leak caused by loop allocation. Add a free helper to free spaces allocated by get_zeroed_page(). Signed-off-by: Haoxiang Li Acked-by: Heiko Carstens Link: https://lore.kernel.org/r/20250218034104.2436469-1-haoxiang_li2024@163.com Signed-off-by: Vasily Gorbik Signed-off-by: Sasha Levin

s390/sclp: Add check for get_zeroed_page()

2025-05-02T05:47:01+00:00

[ Upstream commit 3db42c75a921854a99db0a2775814fef97415bac ] Add check for the return value of get_zeroed_page() in sclp_console_init() to prevent null pointer dereference. Furthermore, to solve the memory leak caused by the loop allocation, add a free helper to do the free job. Signed-off-by: Haoxiang Li Acked-by: Heiko Carstens Link: https://lore.kernel.org/r/20250218025216.2421548-1-haoxiang_li2024@163.com Signed-off-by: Vasily Gorbik Signed-off-by: Sasha Levin

s390/sclp_vt220: Convert newlines to CRLF instead of LFCR

2024-10-22T13:56:44+00:00

commit dee3df68ab4b00fff6bdf9fc39541729af37307c upstream. According to the VT220 specification the possible character combinations sent on RETURN are only CR or CRLF [0]. The Return key sends either a CR character (0/13) or a CR character (0/13) and an LF character (0/10), depending on the set/reset state of line feed/new line mode (LNM). The sclp/vt220 driver however uses LFCR. This can confuse tools, for example the kunit runner. Link: https://vt100.net/docs/vt220-rm/chapter3.html#S3.2 Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Cc: stable@vger.kernel.org Signed-off-by: Thomas Weißschuh Reviewed-by: Sven Schnelle Link: https://lore.kernel.org/r/20241014-s390-kunit-v1-2-941defa765a6@linutronix.de Signed-off-by: Heiko Carstens Signed-off-by: Greg Kroah-Hartman

s390/sclp: Deactivate sclp after all its users

2024-10-22T13:56:44+00:00

commit 0d9dc27df22d9b5c8dc7185c8dddbc14f5468518 upstream. On reboot the SCLP interface is deactivated through a reboot notifier. This happens before other components using SCLP have the chance to run their own reboot notifiers. Two of those components are the SCLP console and tty drivers which try to flush the last outstanding messages. At that point the SCLP interface is already unusable and the messages are discarded. Execute sclp_deactivate() as late as possible to avoid this issue. Fixes: 4ae46db99cd8 ("s390/consoles: improve panic notifiers reliability") Cc: stable@vger.kernel.org Signed-off-by: Thomas Weißschuh Reviewed-by: Sven Schnelle Link: https://lore.kernel.org/r/20241014-s390-kunit-v1-1-941defa765a6@linutronix.de Signed-off-by: Heiko Carstens Signed-off-by: Greg Kroah-Hartman

s390/sclp: Prevent release of buffer in I/O

2024-08-14T11:52:49+00:00

[ Upstream commit bf365071ea92b9579d5a272679b74052a5643e35 ] When a task waiting for completion of a Store Data operation is interrupted, an attempt is made to halt this operation. If this attempt fails due to a hardware or firmware problem, there is a chance that the SCLP facility might store data into buffers referenced by the original operation at a later time. Handle this situation by not releasing the referenced data buffers if the halt attempt fails. For current use cases, this might result in a leak of few pages of memory in case of a rare hardware/firmware malfunction. Reviewed-by: Heiko Carstens Signed-off-by: Peter Oberparleiter Signed-off-by: Alexander Gordeev Signed-off-by: Sasha Levin

s390/sclp: Fix sclp_init() cleanup on failure

2024-07-25T07:49:15+00:00

[ Upstream commit 6434b33faaa063df500af355ee6c3942e0f8d982 ] If sclp_init() fails it only partially cleans up: if there are multiple failing calls to sclp_init() sclp_state_change_event will be added several times to sclp_reg_list, which results in the following warning: ------------[ cut here ]------------ list_add double add: new=000003ffe1598c10, prev=000003ffe1598bf0, next=000003ffe1598c10. WARNING: CPU: 0 PID: 1 at lib/list_debug.c:35 __list_add_valid_or_report+0xde/0xf8 CPU: 0 PID: 1 Comm: swapper/0 Not tainted 6.10.0-rc3 Krnl PSW : 0404c00180000000 000003ffe0d6076a (__list_add_valid_or_report+0xe2/0xf8) R:0 T:1 IO:0 EX:0 Key:0 M:1 W:0 P:0 AS:3 CC:0 PM:0 RI:0 EA:3 ... Call Trace: [<000003ffe0d6076a>] __list_add_valid_or_report+0xe2/0xf8 ([<000003ffe0d60766>] __list_add_valid_or_report+0xde/0xf8) [<000003ffe0a8d37e>] sclp_init+0x40e/0x450 [<000003ffe00009f2>] do_one_initcall+0x42/0x1e0 [<000003ffe15b77a6>] do_initcalls+0x126/0x150 [<000003ffe15b7a0a>] kernel_init_freeable+0x1ba/0x1f8 [<000003ffe0d6650e>] kernel_init+0x2e/0x180 [<000003ffe000301c>] __ret_from_fork+0x3c/0x60 [<000003ffe0d759ca>] ret_from_fork+0xa/0x30 Fix this by removing sclp_state_change_event from sclp_reg_list when sclp_init() fails. Reviewed-by: Peter Oberparleiter Signed-off-by: Heiko Carstens Signed-off-by: Alexander Gordeev Signed-off-by: Sasha Levin

s390/early: fix sclp_early_sccb variable lifetime

2023-03-10T08:32:53+00:00

[ Upstream commit 639886b71ddef085a0e7bb1f225b8ae3eda5c06f ] Commit ada1da31ce34 ("s390/sclp: sort out physical vs virtual pointers usage") fixed the notion of virtual address for sclp_early_sccb pointer. However, it did not take into account that kasan_early_init() can also output messages and sclp_early_sccb should be adjusted by the time kasan_early_init() is called. Currently it is not a problem, since virtual and physical addresses on s390 are the same. Nevertheless, should they ever differ, this would cause an invalid pointer access. Fixes: ada1da31ce34 ("s390/sclp: sort out physical vs virtual pointers usage") Reviewed-by: Heiko Carstens Signed-off-by: Alexander Gordeev Signed-off-by: Heiko Carstens Signed-off-by: Sasha Levin

use less confusing names for iov_iter direction initializers

2023-02-09T10:28:04+00:00

[ Upstream commit de4eda9de2d957ef2d6a8365a01e26a435e958cb ] READ/WRITE proved to be actively confusing - the meanings are "data destination, as used with read(2)" and "data source, as used with write(2)", but people keep interpreting those as "we read data from it" and "we write data to it", i.e. exactly the wrong way. Call them ITER_DEST and ITER_SOURCE - at least that is harder to misinterpret... Signed-off-by: Al Viro Stable-dep-of: 6dd88fd59da8 ("vhost-scsi: unbreak any layout for response") Signed-off-by: Sasha Levin

zcore: WRITE is "data source", not destination...

2023-02-09T10:28:03+00:00

[ Upstream commit 4ba48e1bae5f68af24d8d71d4f28de9eb658af1d ] Signed-off-by: Al Viro Stable-dep-of: 6dd88fd59da8 ("vhost-scsi: unbreak any layout for response") Signed-off-by: Sasha Levin