kernel/linux.git/lib, branch v6.6.131

lib/bootconfig: check xbc_init_node() return in override path

2026-03-25T10:06:10+00:00

[ Upstream commit bb288d7d869e86d382f35a0e26242c5ccb05ca82 ] The ':=' override path in xbc_parse_kv() calls xbc_init_node() to re-initialize an existing value node but does not check the return value. If xbc_init_node() fails (data offset out of range), parsing silently continues with stale node data. Add the missing error check to match the xbc_add_node() call path which already checks for failure. In practice, a bootconfig using ':=' to override a value near the 32KB data limit could silently retain the old value, meaning a security-relevant boot parameter override (e.g., a trace filter or debug setting) would not take effect as intended. Link: https://lore.kernel.org/all/20260318155847.78065-2-objecting@objecting.org/ Fixes: e5efaeb8a8f5 ("bootconfig: Support mixing a value and subkeys under a key") Signed-off-by: Josh Law Signed-off-by: Masami Hiramatsu (Google) Signed-off-by: Sasha Levin

lib/bootconfig: check bounds before writing in __xbc_open_brace()

2026-03-25T10:05:54+00:00

commit 560f763baa0f2c9a44da4294c06af071405ac46f upstream. The bounds check for brace_index happens after the array write. While the current call pattern prevents an actual out-of-bounds access (the previous call would have returned an error), the write-before-check pattern is fragile and would become a real out-of-bounds write if the error return were ever not propagated. Move the bounds check before the array write so the function is self-contained and safe regardless of caller behavior. Link: https://lore.kernel.org/all/20260312191143.28719-3-objecting@objecting.org/ Fixes: ead1e19ad905 ("lib/bootconfig: Fix a bug of breaking existing tree nodes") Cc: stable@vger.kernel.org Signed-off-by: Josh Law Signed-off-by: Masami Hiramatsu (Google) Signed-off-by: Greg Kroah-Hartman

lib/bootconfig: fix snprintf truncation check in xbc_node_compose_key_after()

2026-03-25T10:05:54+00:00

commit 1120a36bb1e9b9e22de75ecb4ef0b998f73a97f1 upstream. snprintf() returns the number of characters that would have been written excluding the NUL terminator. Output is truncated when the return value is >= the buffer size, not just > the buffer size. When ret == size, the current code takes the non-truncated path, advancing buf by ret and reducing size to 0. This is wrong because the output was actually truncated (the last character was replaced by NUL). Fix by using >= so the truncation path is taken correctly. Link: https://lore.kernel.org/all/20260312191143.28719-4-objecting@objecting.org/ Fixes: 76db5a27a827 ("bootconfig: Add Extra Boot Config support") Cc: stable@vger.kernel.org Signed-off-by: Josh Law Signed-off-by: Masami Hiramatsu (Google) Signed-off-by: Greg Kroah-Hartman

lib/bootconfig: fix off-by-one in xbc_verify_tree() unclosed brace error

2026-03-25T10:05:54+00:00

commit 39ebc8d7f561e1b64eca87353ef9b18e2825e591 upstream. __xbc_open_brace() pushes entries with post-increment (open_brace[brace_index++]), so brace_index always points one past the last valid entry. xbc_verify_tree() reads open_brace[brace_index] to report which brace is unclosed, but this is one past the last pushed entry and contains stale/zero data, causing the error message to reference the wrong node. Use open_brace[brace_index - 1] to correctly identify the unclosed brace. brace_index is known to be > 0 here since we are inside the if (brace_index) guard. Link: https://lore.kernel.org/all/20260312191143.28719-2-objecting@objecting.org/ Fixes: ead1e19ad905 ("lib/bootconfig: Fix a bug of breaking existing tree nodes") Cc: stable@vger.kernel.org Signed-off-by: Josh Law Reviewed-by: Steven Rostedt (Google) Signed-off-by: Masami Hiramatsu (Google) Signed-off-by: Greg Kroah-Hartman

Remove WARN_ALL_UNSEEDED_RANDOM kernel config option

2026-03-04T12:21:00+00:00

[ Upstream commit 7dff99b354601dd01829e1511711846e04340a69 ] This config option goes way back - it used to be an internal debug option to random.c (at that point called DEBUG_RANDOM_BOOT), then was renamed and exposed as a config option as CONFIG_WARN_UNSEEDED_RANDOM, and then further renamed to the current CONFIG_WARN_ALL_UNSEEDED_RANDOM. It was all done with the best of intentions: the more limited rate-limited reports were reporting some cases, but if you wanted to see all the gory details, you'd enable this "ALL" option. However, it turns out - perhaps not surprisingly - that when people don't care about and fix the first rate-limited cases, they most certainly don't care about any others either, and so warning about all of them isn't actually helping anything. And the non-ratelimited reporting causes problems, where well-meaning people enable debug options, but the excessive flood of messages that nobody cares about will hide actual real information when things go wrong. I just got a kernel bug report (which had nothing to do with randomness) where two thirds of the the truncated dmesg was just variations of random: get_random_u32 called from __get_random_u32_below+0x10/0x70 with crng_init=0 and in the process early boot messages had been lost (in addition to making the messages that _hadn't_ been lost harder to read). The proper way to find these things for the hypothetical developer that cares - if such a person exists - is almost certainly with boot time tracing. That gives you the option to get call graphs etc too, which is likely a requirement for fixing any problems anyway. See Documentation/trace/boottime-trace.rst for that option. And if we for some reason do want to re-introduce actual printing of these things, it will need to have some uniqueness filtering rather than this "just print it all" model. Fixes: cc1e127bfa95 ("random: remove ratelimiting for in-kernel unseeded randomness") Acked-by: Jason Donenfeld Signed-off-by: Linus Torvalds Signed-off-by: Sasha Levin

flex_proportions: make fprop_new_period() hardirq safe

2026-02-06T15:48:25+00:00

commit dd9e2f5b38f1fdd49b1ab6d3a85f81c14369eacc upstream. Bernd has reported a lockdep splat from flexible proportions code that is essentially complaining about the following race: run_timer_softirq - we are in softirq context call_timer_fn writeout_period fprop_new_period write_seqcount_begin(&p->sequence); ... blk_mq_end_request() blk_update_request() ext4_end_bio() folio_end_writeback() __wb_writeout_add() __fprop_add_percpu_max() if (unlikely(max_frac < FPROP_FRAC_BASE)) { fprop_fraction_percpu() seq = read_seqcount_begin(&p->sequence); - sees odd sequence so loops indefinitely Note that a deadlock like this is only possible if the bdi has configured maximum fraction of writeout throughput which is very rare in general but frequent for example for FUSE bdis. To fix this problem we have to make sure write section of the sequence counter is irqsafe. Link: https://lkml.kernel.org/r/20260121112729.24463-2-jack@suse.cz Fixes: a91befde3503 ("lib/flex_proportions.c: remove local_irq_ops in fprop_new_period()") Signed-off-by: Jan Kara Reported-by: Bernd Schubert Link: https://lore.kernel.org/all/9b845a47-9aee-43dd-99bc-1a82bea00442@bsbernd.com/ Reviewed-by: Matthew Wilcox (Oracle) Cc: Joanne Koong Cc: Miklos Szeredi Cc: Signed-off-by: Andrew Morton Signed-off-by: Greg Kroah-Hartman

lib/crypto: aes: Fix missing MMU protection for AES S-box

2026-01-17T15:29:52+00:00

commit 74d74bb78aeccc9edc10db216d6be121cf7ec176 upstream. __cacheline_aligned puts the data in the ".data..cacheline_aligned" section, which isn't marked read-only i.e. it doesn't receive MMU protection. Replace it with ____cacheline_aligned which does the right thing and just aligns the data while keeping it in ".rodata". Fixes: b5e0b032b6c3 ("crypto: aes - add generic time invariant AES cipher") Cc: stable@vger.kernel.org Reported-by: Qingfang Deng Closes: https://lore.kernel.org/r/20260105074712.498-1-dqfext@gmail.com/ Acked-by: Ard Biesheuvel Link: https://lore.kernel.org/r/20260107052023.174620-1-ebiggers@kernel.org Signed-off-by: Eric Biggers Signed-off-by: Greg Kroah-Hartman

idr: fix idr_alloc() returning an ID out of range

2026-01-11T14:22:17+00:00

commit c6e8e595a0798ad67da0f7bebaf69c31ef70dfff upstream. If you use an IDR with a non-zero base, and specify a range that lies entirely below the base, 'max - base' becomes very large and idr_get_free() can return an ID that lies outside of the requested range. Link: https://lkml.kernel.org/r/20251128161853.3200058-1-willy@infradead.org Fixes: 6ce711f27500 ("idr: Make 1-based IDRs more efficient") Signed-off-by: Matthew Wilcox (Oracle) Reported-by: Jan Sokolowski Reported-by: Koen Koning Reported-by: Peter Senna Tschudin Closes: https://gitlab.freedesktop.org/drm/xe/kernel/-/issues/6449 Reviewed-by: Christian König Cc: Signed-off-by: Andrew Morton Signed-off-by: Greg Kroah-Hartman

lib/vsprintf: Check pointer before dereferencing in time_and_date()

2026-01-11T14:21:23+00:00

[ Upstream commit 372a12bd5df0199aa234eaf8ef31ed7ecd61d40f ] The pointer may be invalid when gets to the printf(). In particular the time_and_date() dereferencing it in some cases without checking. Move the check from rtc_str() to time_and_date() to cover all cases. Fixes: 7daac5b2fdf8 ("lib/vsprintf: Print time64_t in human readable format") Signed-off-by: Andy Shevchenko Reviewed-by: Petr Mladek Link: https://patch.msgid.link/20251110132118.4113976-1-andriy.shevchenko@linux.intel.com Signed-off-by: Petr Mladek Signed-off-by: Sasha Levin

maple_tree: fix tracepoint string pointers

2025-12-01T10:41:52+00:00

commit 91a54090026f84ceffaa12ac53c99b9f162946f6 upstream. maple_tree tracepoints contain pointers to function names. Such a pointer is saved when a tracepoint logs an event. There's no guarantee that it's still valid when the event is parsed later and the pointer is dereferenced. The kernel warns about these unsafe pointers. event 'ma_read' has unsafe pointer field 'fn' WARNING: kernel/trace/trace.c:3779 at ignore_event+0x1da/0x1e4 Mark the function names as tracepoint_string() to fix the events. One case that doesn't work without my patch would be trace-cmd record to save the binary ringbuffer and trace-cmd report to parse it in userspace. The address of __func__ can't be dereferenced from userspace but tracepoint_string will add an entry to /sys/kernel/tracing/printk_formats Link: https://lkml.kernel.org/r/20251030155537.87972-1-martin@kaiser.cx Fixes: 54a611b60590 ("Maple Tree: add new data structure") Signed-off-by: Martin Kaiser Acked-by: Liam R. Howlett Cc: Signed-off-by: Andrew Morton Signed-off-by: Greg Kroah-Hartman