kernel.git/fs/pstore/zone.c, branch linux-rolling-lts

pstore/zone: rewrite some comments for better understanding

2025-05-09T19:09:58Z

Rewrite some comments to make it more clear and easier to understand; fix typos. Signed-off-by: Eugen Hristev Link: https://lore.kernel.org/r/20241224154405.295840-1-eugen.hristev@linaro.org Link: https://lore.kernel.org/r/20250117084228.3218024-1-eugen.hristev@linaro.org Signed-off-by: Kees Cook

pstore/zone: avoid dereferencing zero sized ptr after init zones

2025-01-10T16:51:46Z

In psz_init_zones, if the requested area has a total_size less than record_size, kcalloc will be called with c == 0 and will return ZERO_SIZE_PTR. Further, this will lead to an oops. With this patch, in this scenario, it will look like this : [ 6.865545] pstore_zone: total size : 28672 Bytes [ 6.865547] pstore_zone: kmsg size : 65536 Bytes [ 6.865549] pstore_zone: pmsg size : 0 Bytes [ 6.865551] pstore_zone: console size : 0 Bytes [ 6.865553] pstore_zone: ftrace size : 0 Bytes [ 6.872095] pstore_zone: zone dmesg total_size too small [ 6.878234] pstore_zone: alloc zones failed Signed-off-by: Eugen Hristev Link: https://lore.kernel.org/r/20250110125714.2594719-1-eugen.hristev@linaro.org Signed-off-by: Kees Cook

pstore/zone: Don't clear memory twice

2024-03-09T20:33:22Z

There is no need to call memset(..., 0, ...) on memory allocated by kcalloc(). It is already zeroed. Remove the redundant call. Signed-off-by: Christophe JAILLET Link: https://lore.kernel.org/r/fa2597400051c18c6ca11187b0e4b906729991b2.1709972649.git.christophe.jaillet@wanadoo.fr Signed-off-by: Kees Cook

pstore/zone: Add a null pointer check to the psz_kmsg_read

2024-02-22T18:37:22Z

kasprintf() returns a pointer to dynamically allocated memory which can be NULL upon failure. Ensure the allocation was successful by checking the pointer validity. Signed-off-by: Kunwu Chan Link: https://lore.kernel.org/r/20240118100206.213928-1-chentao@kylinos.cn Signed-off-by: Kees Cook

pstore/zone: Use GFP_ATOMIC to allocate zone buffer

2022-10-17T20:14:10Z

There is a case found when triggering a panic_on_oom, pstore fails to dump kmsg. Because psz_kmsg_write_record can't get the new buffer. Handle this by using GFP_ATOMIC to allocate a buffer at lower watermark. Signed-off-by: Qiujun Huang Fixes: 335426c6dcdd ("pstore/zone: Provide way to skip "broken" zone for MTD devices") Cc: WeiXiong Liao Cc: stable@vger.kernel.org Signed-off-by: Kees Cook Link: https://lore.kernel.org/r/CAJRQjofRCF7wjrYmw3D7zd5QZnwHQq+F8U-mJDJ6NZ4bddYdLA@mail.gmail.com

pstore/zone: cleanup "rcnt" type

2022-06-23T15:27:52Z

The info->read() function returns ssize_t. That means that info->read() either returns either negative error codes or a positive number representing the bytes read. The "rcnt" variable should be declared as ssize_t as well. Most places do this correctly but psz_kmsg_recover_meta() needed to be fixed. This code casts the "rcnt" to int. That is unnecessary when "rcnt" is already signed. It's also slightly wrong because if info->read() returned a very high (more than INT_MAX) number of bytes then this might treat that as an error. This bug cannot happen in real life, so it doesn't affect run time, but static checkers correctly complain that it is wrong. fs/pstore/zone.c:366 psz_kmsg_recover_data() warn: casting 'rcnt' truncates high bits Signed-off-by: Dan Carpenter Signed-off-by: Kees Cook Link: https://lore.kernel.org/r/YrRtPSFHDVJzV6d+@kili

pstore/zone: fix a kernel-doc markup

2021-01-21T21:06:00Z

The documented struct is psz_head and not psz_buffer. Reviewed-by: Kees Cook Signed-off-by: Mauro Carvalho Chehab Link: https://lore.kernel.org/r/a67ca4d12c3ef277dadb9e0d0df8450158e637cc.1610610937.git.mchehab+huawei@kernel.org Signed-off-by: Jonathan Corbet

pstore/zone: cap the maximum device size

2020-12-01T19:32:55Z

Introduce an abritrary 128MiB cap to avoid malloc failures when using a larger block device. Signed-off-by: Christoph Hellwig Reviewed-by: WeiXiong Liao Reviewed-by: Kees Cook Signed-off-by: Kees Cook Link: https://lore.kernel.org/r/20201016132047.3068029-2-hch@lst.de

treewide: Use fallthrough pseudo-keyword

2020-08-23T22:36:59Z

Replace the existing /* fall through */ comments and its variants with the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary fall-through markings when it is the case. [1] https://www.kernel.org/doc/html/v5.7/process/deprecated.html?highlight=fallthrough#implicit-switch-case-fall-through Signed-off-by: Gustavo A. R. Silva

pstore/blk: Support non-block storage devices

2020-06-01T02:49:00Z

Add support for non-block devices (e.g. MTD). A non-block driver calls pstore_blk_register_device() to register iself. In addition, pstore/zone is updated to handle non-block devices, where an erase must be done before a write. Without this, there is no way to remove records stored to an MTD. Signed-off-by: WeiXiong Liao Link: https://lore.kernel.org/lkml/20200511233229.27745-10-keescook@chromium.org/ Co-developed-by: Kees Cook Signed-off-by: Kees Cook